78 - Neonatal Management of Congenital Heart Disease

1393

78 Neonatal Management of Congenital Heart DiseaseMARTIN L. BOCKS, BRIAN A. BOE, AND MARK E. GALANTOWICZ

congenital heart disease typically requiring medical man-agement, catheter-based interventions, or surgeries in the neonatal period. It describes current approaches to moder-ate and severe forms of congenital heart disease in which neonatal palliation or treatment is required to avoid early mortality or long-term disability. The chapter also discusses those situations in which early intervention would not alter clinical course and for which the best course of manage-ment may be cardiac transplantation or palliative comfort measures.

Moderate and severe forms of congenital heart disease can be largely grouped as cyanotic and acyanotic condi-tions (Table 78.1). Within these major silos, conditions can also be classified based on the degree of pulmonary blood flow and whether or not they are dependent on the patent ductus arteriosus (PDA) for either pulmonary or systemic blood flow. By classifying these conditions in this manner, neonatologists will be able to more readily identify the major physiologic deficit and anticipate necessary treat-ment options. For patients requiring surgery in the neonatal period, the focus within this chapter is on the indications and types of surgery that can be offered. The postopera-tive management of these patients is not discussed, as a detailed description of the theories and summary of avail-able evidenced-based practice is outside the scope of this chapter.

Cyanotic Congenital Heart Conditions

Cyanotic congenital heart disease (CCHDs) includes a broad class of anatomic and physiologic derangements that result in patients with decreased systemic oxygenation following birth, including 1) obstruction to pulmonary blood flow with an intracardiac shunt such as an atrial septal defect (ASD) or VSD or 2) admixture lesions in which there is a common site for mixing of systemic and pulmonary venous blood (atria or ventricles) which is pumped to both circula-tions, 3) transposition physiology in which systemic venous blood is pumped to the systemic circulation, 4) pure right to

Introduction

Neonates with congenital heart disease require a well-integrated and multidisciplinary team approach to achieve optimal outcomes. The complexity of managing a critically ill newborn is compounded greatly when the cardiovascular physiology and/or anatomy are significantly altered. Many of the important management principles routinely followed by neonatologists can be applied to critically ill newborn cardiac patients, including thermal regulation, prematurity issues, nutritional strategies, and ventilator support. However, cardiac-specific management strategies, procedures, and surgeries are often required during the neonatal period for patients with congenital heart disease (CHD). These unique strategies must be understood and carefully integrated into the management plan. The objective of this chapter is to describe these management strategies and procedures typi-cally performed based on the prevailing anatomic or physi-ologic deficit faced by the infant during the neonatal period, as opposed to each specific anatomic variant of CHD. Since many of these conditions have similar underlying physiolo-gies as well as early goals for palliation or treatment, the strategies employed can be applied to many different disease conditions.

As described in earlier chapters, the vast majority of con-genital heart conditions (e.g., small ventricular septal defects [VSD] or bicuspid aortic valves) either do not require any interventions whatsoever or require interventional or surgi-cal procedures later in infancy or early childhood. Although patients in the latter category may be managed in the neo-natal ICU or co-managed with the pediatric cardiology service, their clinical courses are often straightforward and team discussions are typically focused on the anticipated follow-up and postdischarge planning. Examples of such conditions include the “pink” tetralogy of Fallot patient that will undergo surgical repair at 4-6 months of age or the mild valvar pulmonary stenosis patient that develops worsening obstruction in the coming months requiring balloon pulmonary valvuloplasty. This chapter focuses on

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1393.e1CHAPTER 78 Neonatal Management of Congenital Heart Disease

Keywords

congenital heart diseasemedical managementinterventionsprostaglandinheart surgerysystemic-pulmonary shuntstentsballoon septostomy

Abstract

Neonates with congenital heart disease require a well-integrated and multidisciplinary team approach to achieve optimal outcomes. The complexity of managing a critically ill newborn is compounded greatly when the cardiovas-cular physiology and/or anatomy are significantly altered. Many of the important management principles routinely followed by neonatologists can be applied to critically ill congenital heart patients; however, cardiac-specific manage-ment strategies, procedures, and surgeries are often required during this period to allow for long-term survival and to avoid significant morbidity. These unique strategies must be understood and carefully integrated into the management plan. The objective of this chapter is to describe these man-agement strategies and procedures that are used to achieve early repair or temporary palliation for these many different disease conditions.


1394 1394 part 12 The Cardiovascular System

desaturation. The specific anatomic or physiologic issue causing the limited PBF varies considerably and, therefore, the approach to augment pulmonary blood flow is situation dependent. The different methods and approaches used to increase pulmonary blood flow are described in this section.

Balloon Pulmonary ValvuloplastyBalloon pulmonary valvuloplasty (BPV) was first described by Kan in 198227 and is an effective strategy to increase pulmonary blood flow in patients with either isolated pulmo-nary valve stenosis or when found in combination in more complex congenital heart disease (Fig. 78.1A, B). Current indications for balloon pulmonary valvuloplasty include patients with either critical pulmonary stenosis (ductal- dependent pulmonary blood flow and/or severe right ven-tricular dysfunction) or in a patient with a peak instantaneous gradient of ≥40 mm Hg on echocardiography.16 The proce-dure typically results in a significant reduction in the pressure gradient across the valve and carries very good mid- and late-term results.11,59,63 A small number of patients will develop significant subvalvar gradient immediately following balloon pulmonary valvuloplasty secondary to significant right ven-tricular hypertrophy and infundibular narrowing. This tem-porary obstruction can be managed medically with increased right ventricular volume and beta blockers.60 Balloon pul-monary valvuloplasty can also be performed in patients with tetralogy of Fallot when the predominant level of obstruction is at the valvar level. This is typically a palliative intervention to allow patients to mature and grow until a complete repair can be done at 4-6 months of age.

Pulmonary Valve Perforation With Balloon Pulmonary ValvuloplastyPulmonary atresia with intact ventricular septum is a right-sided obstructive lesion in which there is no antegrade

left shunting (e.g., pulmonary arteriovenous (AV) malforma-tions). The first three broad categories are more frequently encountered in the neonatal period and will be discussed more in the coming sections. The therapies required for pal-liation or repair of CCHDs differ tremendously within these three classes depending on other anatomic variations that are present. For example, in the admixture lesion tricuspid atresia, pulmonary blood flow is determined by the size of the VSD and relationship of the great arteries. If the VSD is large and the great arteries are normally related (i.e., the pulmo-nary artery arises off the rudimentary right ventricle), there is normal to increased pulmonary blood flow. This infant’s oxygen level will be fairly normal in the neonatal period. However, if the VSD is restrictive and/or the great arteries are transposed (i.e., the pulmonary artery is remote from the VSD and right ventricle), pulmonary blood flow can be considerably limited, resulting in significantly low oxygen levels in the absence of a PDA. Therefore, as we discuss cyanotic congenital heart disease palliation and treatment, the following sections focus more on the immediate goals required to stabilize, palliate, or definitively treat patients in the neonatal period, including approaches for maintaining patency of the ductus arteriosus and less on the specific type of CCHD. Historically, most of these conditions requiring neonatal treatment were managed in the operating room, including a number of surgeries still currently performed (Table 78.2). However, advancements in device technology and increasingly available devices small enough for neonatal use, has led to an increasing number of CCHD that are treated via transcatheter interventions (Table 78.3).

Procedures to Increase Pulmonary Blood Flow

There are many CCHDs in which obstruction of pulmonary blood flow (PBF) is the underlying etiology for systemic

Cyanotic Acyanotic

Right-side Obstruction Admixture Lesions TranspositionPhysiology

Left-side Obstruction

Left-to-right Shunts

Pulmonary atresia with intact ventricular septum

Pulmonary atresia, VSD, and MAPCAs

Pulmonary stenosisTetralogy of Fallot

Common atrium

Double inlet left ventricle

Double outlet right ventricleHypoplastic right/left heart

syndromeTotal anomalous pulmonary

venous connectionTricuspid atresiaTruncus arteriosus

Transition of the great arteries

Aortic stenosis

Coarctation of the aorta

Interrupted aortic arch

Atrial septal defect

Atrioventricular septal defect

Patent ductus arteriosusVentricular septal defect

MAPCA, Major aortopulmonary collateral arteries; VSD, ventricular septal defect.

Physiologic Classification of Congenital Heart DiseaseTABLE

78.1


1395CHAPTER 78 Neonatal Management of Congenital Heart Disease

Primary Problem Hemodynamic Etiology Defects Intervention(s) Result

Cyanosis Atrial septal restriction d-TGA with restrictive atrial septum

Balloon atrial septostomy

Improvement in atrial mixing and oxygen saturation

Decreased pulmonary blood flow

Critical pulmonary stenosis

Pulmonary atresia

TOF

BT shunt occlusion (HLHS, TOF, TA, PA)

Balloon pulmonary valvuloplasty

Valve perforation and valvuloplasty

RVOT stentingPDA stentingBT shunt balloon

dilation and/or stenting

Improvement in pulmonary blood flow and oxygen saturation

Left-sided obstruction

Left ventricular outflow tract obstruction

Critical aortic stenosis

Critical coarctation

Balloon aortic valvuloplasty

Angioplasty/stenting of coarctation

Decrease left-sided obstruction

Decreased cardiac output

Pulmonary overcirculation causing congestive heart failure

Patent ductus arteriosusAtrial septal defect*Ventricular septal defect

Device closure* Eliminate or decrease left-to-right shunt

Vascular obstruction

SVC syndrome Typically iatrogenic Angioplasty and/or stent*

Unobstructed flow

BT, Blalock-Taussig; HLHS, hypoplastic left heart syndrome; PA, pulmonary artery; PV, pulmonary vein; RVOT, right ventricular outflow tract; SV, single ventricle; SVC, superior vena cava; TA, tricuspid atresia; TAPVR, total anomalous pulmonary venous return; TGA, transposition of the great arteries; TOF, tetralogy of Fallot.*Only rarely performed in the neonatal period.

Neonatal Cardiac Lesions and Typical Catheter-Based TherapyTABLE

78.3

Named Surgery Surgical Description Purpose

Norwood Anastomosis of PA to hypoplastic ascending aorta, arch augmentation

Create new “aorta” from pulmonary trunk and patch

Damus-Kaye-Stansel Anastomosis of PA to ascending aorta Combine great arteries for systemic flow to bypass subaortic obstruction

Blalock-Taussig shunt Gore-Tex tube from subclavian artery to PA Supply pulmonary blood flow

Sano shunt Gore-Tex tube from the RV to PA Supply pulmonary blood flow

Bidirectional Glenn Anastomosis between SVC and PAs Supply low-pressure pulmonary blood flow

Fontan Anastomosis between IVC and PAs Supply low-pressure pulmonary blood flow

Jatene Arterial switch for d-transposition of the great arteries

Anatomical correction

Rastelli VSD closure and RV-PA conduit placement Create new “main pulmonary artery”

IVC, Inferior vena cava; PA, pulmonary artery; RV, right ventricle; SVC, superior vena cava; VSD, ventricular septal defect.

Common Named Cardiac Operations Performed in InfantsTABLE

78.2

flow from the right ventricle, and pulmonary blood flow is entirely dependent on the PDA. Complete mixing occurs at the atrial level, and all blood is pumped from the left ventricle to the aorta. In this condition, neonates must be started on prostaglandins to maintain ductal patency immediately after birth. If the tricuspid valve and right

ventricle are of adequate size, a biventricular repair may be considered. In these situations, patients will be referred to the catheterization laboratory to ensure the coronary arteries fill normally from the aorta and not the hyperten-sive right ventricle (i.e., not right ventricular–dependent coronary circulation). Pulmonary valve perforation with



Right Ventricular Outflow Tract StentingSevere obstruction of the right ventricular outflow tract (RVOT) can be seen in patients with tetralogy of Fallot and double outlet right ventricle leading to severe cyanosis. Some patients will undergo a complete surgical repair in the neonatal period depending on the patient’s weight, size of branch pulmonary arteries, and extracardiac medical issues. Certain centers will perform aortopulmonary shunts (see below) for cyanotic patients with small branch pulmonary arteries and bring them back for complete surgical repair at 4-6 months of age. Balloon pulmonary valvuloplasty is typi-cally not effective in this anatomy given the severe subval-vular obstruction across the right ventricular outflow tract. Over the past 10 years, centers have started palliating these patients by implanting stents across the right ventricular outflow tract.12,20 During the procedure, the RVOT and main pulmonary artery are imaged using angiography. The RVOT is then crossed with a catheter, and wire position is established to guide the procedure. A stent is selected based on the size of the right ventricular outflow tract. The stent is advanced over the wire and typically through a long introducer sheath until it is positioned across the RVOT. The stent is deployed within the RVOT and follow-up angiog-raphy is then performed to assess the adequacy of antegrade flow through the implanted stent. Multiple stents may need to be placed depending on the anatomy of the right ven-tricular outflow tract. Most patients maintained on prosta-glandins can be weaned off the medication following stent implantation within the right ventricular outflow tract. In premature or small neonates or those with vascular access issues, hybrid per-ventricular stenting of the RVOT, whereby

balloon pulmonary valvuloplasty is indicated in patients with favorable anatomy (membranous atresia) without right ventricular–dependent coronary circulation. This intervention was first reported by Latson in 1991.31 The technique involves advancing a guidance catheter ante-grade from the femoral vein, across the tricuspid valve, and into position directly beneath the atretic pulmonary valve. The optimal target site for perforation is then defined by both right ventricle angiography and aortic angiography, which fills the main pulmonary artery via the PDA. Cur-rently, the most commonly performed method to perfo-rate the membrane is to advance a small radiofrequency (RF) wire within the guide catheter into contact with the membrane. The RF wire delivers a focused energy pulse at the tip to precisely “burn” a small hole in the pulmonary valve membrane. The RF wire is passed through the pul-monary valve membrane into the main pulmonary artery. Perforation can also be accomplished by using a small cor-onary wire, but the RF wire approach is considered safer and more controlled. Once the valve is perforated and crossed, balloon pulmonary valvuloplasty is performed (Fig. 78.2A-D). This procedure can result in improved antegrade flow from the right ventricle to the pulmonary artery, often allowing for the eventual discontinuation of prostaglandins. This process can sometimes take many weeks before prostaglandins can be discontinued and months before growth of the annulus and entire right ven-tricular outflow tract is observed. It is not uncommon for patients to require repeat balloon pulmonary valvuloplasty in the first 6 months. If repeat balloon pulmonary valvu-loplasty does not result in adequate antegrade pulmonary blood flow, surgical intervention is typically required.35

BA

• Fig. 78.1 Balloon pulmonary valvuloplasty in a neonate with critical pulmonary valve stenosis. A baseline lateral angiogram shows the stenotic and doming pulmonary valve (A), which then undergoes balloon pulmonary valvuloplasty using a standard balloon (B). During balloon inflation, a waist is seen at the level of the valve annulus.



ventricular outflow tract obstruction whereby the actual technique used depends on the level of obstruction—valvar, supravalvar, or subvalvar—and can range from a simple pulmonary valvotomy or valvectomy to a complete transan-nular patch opening of the subvalvar, pulmonary valve, and supravalvar regions. The resultant pulmonary insufficiency is usually very well tolerated.

Implantation of a Stent in the Ductus ArteriosusThere are many congenital heart defects in which pulmonary blood flow is dependent on flow via the ductus arteriosus. The most common of these lesions are the more severe cases of tetralogy of Fallot. Additional congenital heart lesions where pulmonary blood flow is dependent on ductal arte-rial flow includes pulmonary atresia with and without a

the pediatric heart surgeon places the sheath directly into the right ventricle via a small sub-xiphoid incision, allows effective palliation in this challenging population.10 In either approach, these stents are removed at the time of surgical repair, which is ultimately delayed to allow for growth in both the patient and branch pulmonary arteries.55

Surgical Opening of the Right Ventricular Outflow TractIn neonates that are not candidates for a complete surgical repair or palliation with balloon angioplasty/stenting of the RVOT, either percutaneously or using hybrid techniques, an open surgical procedure can be used. The operation is performed via a median sternotomy on cardiopulmonary bypass. The goal of the procedure is complete relief of right

C D

BA

• Fig. 78.2 Pulmonary valve perforation in a neonate with pulmonary atresia and intact ventricular septum. The lateral view of the right ventricular outflow tract angiogram confirms the diagnosis (A). Simultaneous right ventricular and aortic angiogram show both sides of the pulmonary valve plate (B). The valve is perforated with a radiofrequency wire (C), and subsequent balloon valvuloplasty results in good antegrade flow through the right ventricular outflow tract (D).



ductus arteriosus. A guide wire is used to carefully cross the often tortuous ductus arteriosus and used for procedural guidance. An appropriately sized stent is then advanced over the wire and deployed across the ductus arteriosus (Fig. 78.3A-C). This interventional palliation procedure can last many months until the patient can undergo complete surgical repair.53

Systemic to Pulmonary Artery ShuntsThe ability to augment pulmonary blood flow by a surgi-cally created shunt between the aorta, or one of its branches, and the central pulmonary arteries has a long history dating back to 1945 with the introduction of the Blalock-Taussig (BT) shunt. The classic BT shunt was performed using the divided subclavian artery as an end-to-side anastomosis to the pulmonary artery. Soon other shunt techniques were introduced, such as the Potts shunt, a direct anastomosis between the descending aorta and the left pulmonary artery,

VSD, double outlet right ventricle with pulmonary atresia, and some forms of tricuspid atresia. The vast majority of these patients are typically treated with surgical palliation, including an aortopulmonary shunt (e.g., modified Blalock-Taussig shunt). Similar to RVOT stenting, advancements in catheter-based technology and techniques have allowed for some of these patients to be palliated by implantation of a stent in the ductus arteriosus. The procedure is typically performed retrograde from the femoral artery or via a vessel off the aortic arch (carotid or axillary artery). The procedure may also be accomplished antegrade from the femoral vein, particularly when there is antegrade flow through the right ventricular outflow tract.58 The prostaglandin infusion is usually stopped a few hours before the anticipated start of the procedure to allow for some constriction of the ductus arteriosus to occur. Prostaglandins are kept in line in case of severe ductal spasm causing profound cyanosis. Angiog-raphy is performed to delineate the length and size of the

C

BA

• Fig. 78.3 Stent implantation within a ductus arteriosus in a patient with pulmonary atresia and intact ventricular septum. Aortic angio-gram shows a tortuous ductus arteriosus originating off the lesser curvature of the distal aortic arch (A). The ductus arteriosus becomes relatively straight after being crossed with a wire (B), and two coro-nary artery stents are implanted within the vessel (C).



Pulmonary Artery BandingThe current mantra in congenital heart surgery is early complete repair due to improved operative techniques as well as improved peri-operative management, resulting in excellent outcomes even with complex neonatal CHD. Therefore, the tendency is away from palliating babies to allow for growth or an older age before two ventricle repair is considered. Nevertheless, there are certain forms of CHD in which a palliative step, such as pulmonary artery banding to restrict pulmonary blood flow is neces-sary before complete repair is attempted. Examples include anatomic defects that continue to carry a higher risk of suboptimal early repair, such as multiple apical ventricular septal defects or patients with otherwise repairable anoma-lies, but have significant associated co-morbidities, such as prematurity or intracerebral hemorrhage. In these situa-tions, a pulmonary artery band can be an effective palliative technique to control pulmonary blood flow. Also, pulmo-nary banding is frequently used as a first-stage procedure in the management of certain single ventricle physiologies, such as tricuspid atresia or double inlet left ventricle. The procedure can be performed via a thoracotomy or sternot-omy depending on the anatomy, planned concomitant pro-cedures, and surgeon preference. Technical aspects include creating a space between the aorta and main pulmonary artery through which a nondistensible band of prosthetic material is passed as a ring around the main pulmonary artery. The band is located between the valve and the origin of the branch pulmonary arteries. The band is then tight-ened to the desired effect again based on the underlying anatomy, physiology, and planned next stage. In general, the goals of a pulmonary artery band are to improve the balance of systemic to pulmonary artery circulation and to protect the distal pulmonary vasculature from unrestricted pressure and flow. Achievement of balanced flow guided by the changes in systemic oxygen saturation with tightening, and the pressure restriction is demonstrated by reduction in the pulmonary artery pressure distal to the band. In patients without a main pulmonary artery, such as truncus arteriosus, and those in which complete neonatal repair is not possible, separate banding of the left and right branch pulmonary arteries is possible. Recovery from pulmonary artery banding is usually fairly quick and patients are often easier to manage once the degree of PBF is appropriately restricted.

Procedures to Increase Mixing of Systemic and Pulmonary Venous Blood

Certain forms of cyanotic congenital heart disease are depen-dent on adequate intracardiac mixing of blood to main-tain adequate oxygen saturations in the neonatal period. This includes conditions with transposition physiology and most admixture lesions. When inadequate mixing occurs in patients with admixture lesions, disproportionate streaming of the deoxygenated blood to the systemic circulation results

and the Waterston shunt, a direct anastomosis between the ascending aorta and the right pulmonary artery. These techniques had in common a shunt that not only aug-mented pulmonary blood flow but could palliate over a long period of time because of the growth potential of the native tissue construction of the shunt. These shunt techniques are essentially obsolete today for two reasons: 1) with growth of the shunt there is a lack of control over the amount of pulmonary blood flow creating the risk of pulmonary overcirculation, pulmonary vascular disease, and pulmo-nary hypertension; and 2) the advent of rapid second-stage procedures for successful infant complete repair for two ventricle anatomies or the use of subsequent cavopulmo-nary shunts for single ventricle anatomies. Therefore, today the most common palliative, neonatal surgical shunt is the modified BT shunt whereby a prosthetic graft is anasto-mosed proximally end-to-side to the innominate artery or ascending aorta and distally end-to-side to the central pul-monary artery, with flow being controlled by the diameter of the graft chosen, typically 3-4 mm in a neonate.

Procedures to Decrease Pulmonary Blood Flow

In the previous section, the focus was on cyanotic CHD in which pulmonary blood flow is restricted. The conditions described in that section usually tend to make intuitive sense since less pulmonary blood flow is easily reconciled with cyanosis and hypoxia. However, there are forms of cyanotic heart disease, particularly admixture lesions, in which there is often excessive pulmonary blood flow and arterial saturations are often only mildly decreased.

Admixture lesions are forms of congenital heart disease in which blood from the systemic and pulmonary veins mix within the heart via a single or multiple defects (predomi-nantly at the atrial level). When blood is completely mixed within the heart, then arterial saturation is dependent on the size of the left-to-right shunt or amount of pulmonary blood flow and whether or not there is preferential stream-ing of saturated or desaturated blood to the aorta. Variations in the size and location of the outflow tracts determine where the “mixed” blood is ejected. Patients with admixture lesions and unrestricted pulmonary blood flow develop pulmonary overcirculation which can result in respiratory distress/failure, difficulty feeding, failure to thrive, and potentially necrotizing enterocolitis. If left unabated, exces-sive pulmonary blood flow (PBF) can lead to changes in the pulmonary arterioles causing irreversible elevation of the pulmonary vascular resistance. This is of particular impor-tance for single ventricle patients as elevated pulmonary vascular resistance can make the patient ineligible for even-tual Fontan surgical palliation. To prevent these problems from developing, patients with admixture lesions and exces-sive PBF require interventions to limit or control the amount of flow to the lungs, often as part of a series of staged palliation surgeries for functional single ventricle anatomy and physiology.



this involves the creation of an atrial level communication, and in other cases, enlargement of a restrictive existing communication (patent foramen ovale [PFO] or ASD) is required. In this section, we describe current approaches available to provide unrestrictive atrial level communication for both admixture lesions and conditions with transposi-tion physiology (Table 78.4).

Balloon Atrial SeptostomyBalloon atrial septostomy (BAS) is the standard method for enlarging an existing atrial communication when there is inadequate mixing. The most common indication is d-transposition of the great arteries with restrictive atrial septum, which occurs in one-third of neonates with this condition.5 Following TGA, the second-most common indication for balloon atrial septostomy occurs in the single ventricle admixture lesion HLHS. The balloon atrial septos-tomy procedure has been performed for more than 50 years and remains the optimal approach in most cases because of the relative safety and efficacy when performed by experi-enced operators.

The standard BAS procedure can be done either in the catheterization laboratory or bedside in the neonatal inten-sive care unit. Procedural guidance is typically provided by fluoroscopy, echocardiography, or combination of both. Performing the procedure in the catheterization laboratory allows for additional procedures to be performed (i.e., coro-nary angiography) and allows easy access to additional cath-eterization equipment should the procedure be technically difficult. Bedside BAS under echocardiographic guidance has been shown to be a safe and more cost-effective approach in patients with d-transposition of the great arteries.67 The procedure can be performed via femoral venous access or by taking over the umbilical vein catheter. The BAS catheter is advanced under fluoroscopic or echocardiographic guidance until it is seen to be in the left atrium across an existing PFO/ASD (Fig. 78.4A, B). The balloon is inflated in the left atrium and a quick, forceful, yet controlled, “jerk” is performed to pull the inflated balloon through the exist-ing communication. The septum tears during this process,

in severe cyanosis. To demonstrate this, consider hypoplastic left heart syndrome (HLHS), in which the left-sided struc-tures are not adequate to support a full cardiac output. To provide the systemic circulation with adequate quantities of oxygenated blood, there must be unrestricted flow from the left atrium to the aorta (left atrium→right atrium→right ventricle→pulmonary artery→ductus arteriosus→aorta). Thus, unrestricted atrial communication is necessary for both adequate oxygenation and maintenance of cardiac output. Furthermore, without unrestrictive atrial communication, left atrial hypertension develops because of the inability of pulmonary venous return to unload. This leads to pulmonary venous hypertension and subsequent pulmonary edema with pulmonary artery hypertension. This can be devastating for patients with single ventricle admixture lesions.

In the cyanotic condition d-transposition of the great arteries (D-TGA), the pulmonary and systemic circulations are maintained in parallel as opposed to in series. Oxygen-ated blood is pumped from the right ventricle to the lungs and deoxygenated blood is pumped from the left ventricle to the aorta. Unlike admixture lesions, cardiac output to the systemic circulation is normal and is not dependent on atrial level shunting. Similarly, though, if there is inadequate mixing of blood predominantly at the atrial level, the result-ing physiology is not compatible with survival because of the development of severe hypoxemia. In the early newborn period, for a D-TGA patient with restrictive or intact atrial septum, the patent ductus arteriosus provides the minimal mixing necessary to maintain arterial saturations still com-patible with life. However, as the ductus arteriosus con-stricts, the two circulations have almost no communication and severe prohibitive cyanosis results. For these patients, it is crucial to begin a prostaglandin infusion immediately after birth when the diagnosis is known or suspected. In these situations, despite maintenance of a PDA, severe cya-nosis results as the ductus arteriosus alone is not an adequate source of mixing, and atrial opening is required.

In summary, all admixture lesions and conditions with transposition physiology require adequate mixing at the atrial level for survival in the neonatal period. In some cases,

Diagnosis Reason for Intervention Flow after Intervention Special Considerations

d-Transposition of great arteries Cyanosis Bidirectional

Tricuspid atresia Decreased cardiac output Right-to-left If late—may need blade septostomy or stent placement

Ebstein anomaly Decreased cardiac output Right-to-left

Total anomalous pulmonary venous return

Decreased cardiac output Right-to-left

Hypoplastic left heart syndrome Pulmonary edema Left-to-right If septum is thick—may need septostomy or stent placement

Congenital Heart Lesions That May Require Neonatal Atrial SeptostomyTABLE 78.4



Static Balloon SeptoplastyStatic balloon atrial septoplasty involves inflating a balloon that is stretched across the newly created perforation. As opposed to a standard BAS, a static BAS is repeated several times with progressively larger balloons. Static BAS is rarely effective for a sustained period of time if only standard angio-plasty balloons are utilized. Cutting balloon septoplasty is much more effective at widening a newly created perforation and producing a more sustained outcome. Cutting balloons have four small atherotomes (microsurgical blades) attached to the longitudinal surfaces positioned 90 degrees to each other. These are designed to score the tissue against which it is in contact during inflation. The balloon is deflated and rotated/repositioned, and additional inflations are performed to create more score lines. The opening can then be further dilated with larger diameter static balloons, which tears the tissue along the multiple scored cut lines.

Blade Atrial SeptostomyThe Park blade septostomy catheter is a catheter with a retractable blade at its distal end (Fig. 78.5). Once the atrial septum has been crossed, typically a long sheath is advanced over the wire into the left atrium. The blade septostomy catheter is advanced out the tip of the sheath, which is with-drawn into the right atrium. The blade is then pulled back through the septum, slicing the atrial septal tissue along the way. The blade produces a deeper slice in the atrial tissue compared to the cutting balloons, so it is important that the septum is crossed at a fairly central point. After blade septostomy, the cut hole can then be dilated with progres-sively larger static balloons.

resulting in a larger atrial communication and hopefully unrestricted atrial shunting.

In the event of a thick septum that does not tear, repeat BAS is not advised and a different approach must be sought for the patient. If the patient is profoundly hypoxemic before and during the procedure, it is not uncommon to develop pulmonary hypertension or maintain high pulmo-nary vascular resistance (PVR). In this setting, pulmonary blood flow is restricted and does not allow for enough of the mixed blood to be pumped to the lung to receive oxygen. Profound cyanosis may persist despite echocardio-graphic evidence of an unrestrictive atrial communication. In these situations, patients should be started on inhaled nitric oxide and allowed time for their pulmonary vascu-lar resistance to drop, which results in improved arterial saturations.

Other Atrial Septostomy TechniquesBalloon atrial septostomy may not be effective if the atrial septum is thick or completely intact. If there is an exist-ing communication between the atria, this can be crossed and made larger with other transcatheter interventions. If no atrial communication exists, the atrial septum may be crossed using the radiofrequency wire (described in the RVOT perforation section), a radioperforation transseptal needle, or with a standard transseptal needle.9,23,32 Once the thick or intact septum is perforated, a guidewire can then be passed through the perforation and positioned into a left-sided pulmonary vein. At this point, there are multiple options that the operator can choose for opening the atrial septum, including static balloon septoplasty, blade atrial septostomy, and atrial septal stenting.

BA

• Fig. 78.4 Still fluoroscopic images of a balloon atrial septostomy with transthoracic echocardiographic guidance in a child with d-transposition of the great arteries and restrictive atrial septum. The septostomy balloon is inflated within the left atrium (A) and pulled across the atrial septum into the right atrium/inferior vena cava (B).



complete excision of the atrial septum creating a reliable and durable opening. Surgical atrial septectomy in the neonate is almost exclusively performed on patients with single ven-tricle anatomy and physiology.23

Acyanotic Congenital Heart Conditions

Acyanotic forms of congenital heart disease represent a much more straightforward class compared to the cyanotic conditions discussed in the prior sections. Acyanotic condi-tions that require interventions or medical management in the neonatal period are typically those that involve outflow obstruction. As such, the management approaches tend to be more standardized and consistent, but patient comor-bidity and clinical status can necessitate the use of novel methods of treatment.

Left-Sided Obstruction

Patients born with obstruction on the left side of the heart (e.g., valvar aortic stenosis, interrupted aortic arch, coarcta-tion of the aorta) are often asymptomatic in the immediate newborn period. The oxygen saturation might be normal during the screening pulse oximetry if only checked in the upper extremity. These patients may appear well clinically and have been discharged to home. However, as the ductus arteriosus closes, systemic cardiac output is dramatically reduced and the neonate will present in shock and with end organ dysfunction. Although the incidence of undiagnosed postnatal presentation has dramatically dropped with con-temporary prenatal and postnatal congenital heart disease screening, studies have shown that the prenatal detection rate for isolated aortic arch obstruction still hovers around 20%-30%.51 Therefore, there continues to be a significant number of patients who will present postnatally every year, and the neonatologist will need continued vigilance for these patients. The approaches to dealing with these left-sided obstruction lesions are discussed in the following sections.

Balloon Aortic ValvuloplastyBalloon aortic valvuloplasty is performed in the newborn period in patients who present with critical or severe valvar aortic stenosis. The first reported balloon aortic valvuloplasty was reported in 1983 by Lababidi, and the procedure has been markedly improved upon over the last few decades, pre-dominantly related to the availability of a compliant balloon with very small crossing profiles (down to 3 French).64 Rec-ommendations for limiting the balloon diameter:annulus ratio to 80%-100% has greatly improved the procedural results, in which relief of obstruction is obtained without causing severe degrees of valvar regurgitation.7,38 However, the procedure itself can be technically difficult and has a much higher risk profile in the neonatal population, and balloon aortic valvuloplasty should only be performed by experienced operators and with surgical backup nearby. The condition is most commonly approached retrograde

Atrial Septal StentingIn very small patients with thick and/or intact atrial septa, cutting and static BAS are often ineffective and the blade septostomy unsafe, as the blade is too large for the small left atrium. In these situations, an atrial communication is best created by implanting a premounted stent across the atrial septum. After perforating, crossing the atrial septum, and gaining stable wire position, a long sheath is passed into the left atrium. A premounted stent (typically 6-8 mm in diam-eter) is advanced through the delivery sheath and over the guidewire until half of it is seen in the left atrium using fluoroscopy and transesophageal echocardiography guid-ance. The delivery sheath is slowly retracted and efforts are made to ensure positioning is balanced on both sides. Once this is confirmed, the balloon is inflated and the stent is deployed (Fig. 78.6A-C). The stent is resected with the atrial septectomy procedure during a subsequent planned surgical operation.

Atrial SeptectomyA hybrid approach to opening the atrial septum is some-times an option whereby the surgeon places a sheath directly into the atrium, without the use of cardiopulmonary bypass, through which the interventional cardiologist can perform the atrial septal balloon or stenting techniques previously described. In newborns that are not candidates for hybrid or percutaneous transcatheter strategies to open the atrial septum, a surgical atrial septectomy can be performed. The operation is performed through a median sternotomy on cardiopulmonary bypass. The goal of the operation is

• Fig. 78.5 A blade septostomy performed in a patient with tricuspid atresia who underwent banding of the main pulmonary artery. The procedure involves opening a retractable blade on the end of a cath-eter and making a small slice in the atrial septum. This is followed by a balloon septostomy or septoplasty.



indicated. These operations are performed via a median sternotomy on cardiopulmonary bypass with aortic cross-clamping, allowing direct visualization of the aortic valve. In the newborn with isolated aortic valve stenosis, the most common anatomic construct is a bicuspid or unicuspid valve with fused commissures. In this setting, a controlled commissurotomy can effectively increase the valve orifice without significant insufficiency. Other surgical repair techniques can be utilized depending on the anatomy encountered.

For neonates with aortic valves that cannot be repaired, replacement options are limited and suboptimal, because there are no bioprosthetic valves manufactured small enough to fit a neonate, and even if there were, they cannot grow to match

from the femoral artery but can also be performed via the femoral vein if an atrial communication is present. In smaller patients, the procedure can be performed via a surgical cut-down or direct percutaneous access of the common carotid artery.46 A smaller balloon:annulus ratio can be performed first, with progressively larger balloons if a significant residual pressure gradient remains. Multiple studies have defined a successful neonatal balloon aortic valvuloplasty as a reduced aortic valve gradient ≤35 mm Hg with no worsening aortic valve insufficiency.7,50,61

Surgical Aortic Valve Repair or ReplacementIn newborns with aortic valve stenosis not amenable to transcatheter techniques, surgical repair or replacement is

C

B

A

• Fig. 78.6 Implantation of an atrial septal stent using transesopha-geal echocardiographic guidance in a patient with hypoplastic left heart syndrome and a restrictive atrial septum. A left atrial angiogram shows the restrictive atrial septal defect nearly filled with the long sheath (A). The stent is partially deployed on the left atrial side (B), followed by complete deployment of the stent across the atrial septum (C).



ductus arteriosus to the aortic isthmus. It occurs within the first few days or weeks of life as the constrictive process that normally closes the ductus arteriosus extends into the adjacent aortic tissue leading to the clinical manifestations previously described. In this setting, the typical operation is a coarctation segment resection with a primary end-to-end anastomosis of native aortic tissue. This operation is performed via a thoracotomy without cardiopulmonary bypass. The principles of the operation include division of the ductus arteriosus, complete resection of the coarcta-tion segment of the aorta and any adjacent ductal tissue, and mobilization of the proximal and distal segments of aorta, establishing a tension free end-to-end anastomosis. Sometimes the proximal opening needs to be extended into the undersurface of the distal aortic arch to enlarge that segment, hence the term extended end-to-end anastomo-sis. The benefits of this operation include complete relief of obstruction, and growable and durable repair, at very low risk. The potential downsides of the operation include inability to address any transverse aortic arch hypoplasia as well as a circumferential aortic suture line that may develop resistant scar tissue leading to recurrent stenosis at this site.

The other form of neonatal coarctation is hypoplasia of the entire aortic arch. This is repaired via a median ster-notomy on cardiopulmonary bypass, allowing access to the entire aortic arch. The typical reconstruction includes divi-sion of the ductus arteriosus, resection of ductal tissue, and long segment patch augmentation of the entire aortic arch from distal ascending aorta to mid-descending thoracic aorta. The patch augmentation leaves a posterior wall of native aortic tissue that allows growth of the reconstructed aorta.

Transcatheter Treatment of CoarctationTranscatheter therapies for neonatal coarctation are typi-cally performed when definitive surgical repair is deferred because of patient comorbidities. The most common reason for intervention is a patient presenting in shock because of ductal closure in whom the ductus arteriosus cannot be opened or cannot be opened enough to allow for effective resuscitation and resolution of end organ dysfunction.52 In these situations, the coarctation is treated with balloon angioplasty, during which a balloon is inflated across the lesion to provide temporary relief of the obstruction and resuscitation of end organs until eventual surgical correc-tion can be performed. The most common acute complica-tion associated with balloon angioplasty is femoral arterial injury. Long-term complications of balloon coarctation angioplasty that does not end up needing surgical repair include pseudoaneurysm formation and recurrent coarcta-tion. Recurrent coarctation of the aorta following surgery is often treated in the catheterization laboratory with balloon angioplasty and/or implantation of a stent.6,17 Implanta-tion of a stent across a neonatal coarctation lesion is rarely performed, and usually only when palliative angioplasty alone does not open the obstructed area adequately. The use of primary stenting in the neonatal period is limited by the size of introducer sheath required to implant the stent

the rapid somatic growth of an infant. In these situations, or in infants with combined aortic valvar and left ventricular outflow tract (LVOT) obstruction, the only option is aortic root replacement with either a cryopreserved human cadav-eric homograft or the patient’s own pulmonary valve as an autograft (Ross procedure). The disadvantage of a homograft includes the known risk of early calcification especially in the neonate, leading to valve dysfunction, the lack of growth potential, and the increased risk of repeat coronary artery reimplantation. Therefore, the Ross procedure has become the replacement option of choice in neonates.14,39 The prin-ciples of the operation include reconstructing the LVOT and replacing the aortic valve with the child’s own living tissue—a pulmonary root autograft (rim of right ventricular muscle, valve, and the main pulmonary artery), reimplantation of the coronary arteries, and replacement of the pulmonary valve with a pulmonary valve homograft. In theory, this operation exchanges aortic valve disease for pulmonary valve disease with the reasoning that repeat interventions on the aortic valve carry increasing risk, while repeat interventions on the pulmonary valve are not only less frequent but less risky.

Coarctation of the AortaCoarctation of the aorta is often discovered on prenatal ultrasound and with early postnatal screening. However, as stated above, many cases are still missed even when stan-dard prenatal care is provided. The cases of coarctation detected prenatally are typically the more severe forms, and it is usually recommended that these mothers deliver these infants at centers where neonatal and surgical treatment can be provided. For cases in which prenatal detection has not occurred, postnatal symptoms develop with the advent of ductus arteriosus closure. These symptoms include poor feeding, respiratory distress, and eventually shock-like appearance because of low cardiac output. The postnatal diagnosis is typically confirmed using surface echocardio-gram, which typically shows isthmus hypoplasia (periductal area), a posterior shelf causing flow acceleration on Doppler interrogation, and often varying degrees of transverse arch hypoplasia. The severity and even presence of coarctation of the aorta can often not be fully appreciated in the setting of a moderate- or large-sized patent ductus arteriosus, so it is helpful to get echocardiographic confirmation as soon as possible when a prostaglandin infusion is started. However, in cases of severe low cardiac output, the initiation of pros-taglandins should not be withheld to allow time to obtain the echocardiogram. Coarctation of the aorta that presents in the neonatal period is often long segment and less likely to be discrete. Surgical repair of native coarctation present-ing in the neonatal period remains the standard treatment of choice. Interventional therapies can be considered in certain situations, in which surgery is thought to be too high risk and an interim palliative procedure is required.

Surgical Repair of CoarctationThe most common form of neonatal coarctation is often referred to as “juxtaductal” coarctation, which manifests as a discrete area of aortic narrowing at the junction of the



neonate and, therefore, the timing of when patients are referred for surgical ligation is crucial.

Over the past 5 years, many institutions have started pur-suing transcatheter approaches for neonatal PDA closure using off-label devices approved for other vascular occlusion indications. Transcatheter PDA closure in older infants and children with stainless steel coils and nitinol-based devices has been performed since the 1970s with great success. As a result, PDA surgical ligation outside of the neonatal popula-tion is almost never performed. The unique neonatal ductal anatomy and small patient size have limited the occlusion of neonatal PDAs with traditional FDA-approved devices. However, the development of smaller interventional devices and delivery catheters has now allowed for safe transcath-eter occlusion of the ductus arteriosus in premature neo-nates.33,56,66 Although a learning curve for this procedure exists and widespread experience is limited, by institut-ing a thoughtful and intentional approach, PDA device closure can be performed safely and effectively in premature infants.3,33,56,66 To this point, the FDA recently approved the first device designed for occlusion of a PDA in a neonate (Piccolo, Abbott). The most common complication is arte-rial vascular injury when arterial access is used as part of the procedure.3 When only venous access route is used, obstruction of the left branch pulmonary artery or descend-ing thoracic aorta is the next most commonly observed issue. This is usually discovered before the device is released by angiography or transthoracic echocardiogram, at which time the device can be safely removed and another size or device can be tried, or the patient is referred for surgical ligation. Further research and cumulative experience with both approved (on-label) and off-label devices will hope-fully demonstrate transcatheter PDA closure to be safe and effective for many premature infants.

Miscellaneous Procedures

Some heart conditions or combination of conditions cannot be easily placed into one of the major physiologic groups detailed above or deserve special attention on their own. The following section contains surgical, transcatheter, or hybrid interventions that do not fall fully into one of the rubrics above.

Pulmonary Vein Stenosis

Isolated pulmonary vein stenosis is a rare anomaly in the neonate, is associated with poor outcomes, and is commonly seen in conjunction with other defects. Stenosis of multiple pulmonary veins is associated with pulmonary venous hypo-plasia, poorer prognosis and is more common in infants born extremely premature, especially those with coexisting intracardiac shunt lesion.13 This condition can be congenital or acquired after a pulmonary vein repair operation. Inter-ventional experience with this condition is growing, with multiple case series describing balloon angioplasty (both conventional and cutting balloons) and stent implantation for this lesion.4,47 The process of progressive pulmonary vein

via the femoral artery. This limitation can be overcome by using a hybrid surgical approach via a cut-down on the carotid artery or percutaneously via direct carotid access. Work is currently underway to develop bioresorbable stents that could be implanted in the neonatal period, dissolve over a period of 6-18 months, and then be stented again with larger stents, potentially obviating the need for surgi-cal repair.22

Pulmonary Artery Stenosis

Isolated branch pulmonary artery stenosis outside of the commonly encountered peripheral pulmonic stenosis (PPS) is rarely encountered in the neonatal period. The most common cause is due to constriction of the proximal left pulmonary artery following ductus arteriosus closure. In severe cases, the left pulmonary artery can become com-pletely obstructed or isolated if not treated early. Moderate lesions can typically be treated via balloon angioplasty, but severe lesions often require stent implantation for a sus-tained result. Although there are stents that can be placed in the neonate, many of them cannot be dilated to the size of an adult pulmonary artery. As a result, these stents are placed as a palliative step when future surgical intervention is anticipated. At the time of surgical intervention, these small stents can either be surgically removed or transected, allowing for enlargement of the vessel. Studies have demon-strated that some of these stents may be fractured with high pressure balloons or “unzipped,” but this is highly depen-dent on the type of stent used.40,57 Similar to neonatal stent-ing of aortic coarctation, bioresorbable stents may prove to be a useful therapeutic option in this patient population.37

Treatment of Patent Ductus Arteriosus

A patent ductus arteriosus is commonly encountered in the premature neonate. Large PDAs can result in significant left-to-right shunting with medical consequences, including respiratory failure, renal insufficiency, and feeding intol-erance. The management of hemodynamically significant PDAs in the neonatal period, particularly the premature and extreme premature population, is controversial and very institutional and provider dependent. Longstanding methods for PDA closure include medical therapy with prostaglandin inhibitors and surgical ligation. Medical closure of PDA is covered extensively in other chapters (Chapter 74), so will not be addressed in this section. Sur-gical closure has been the gold standard for over 60 years and remains the standard approach when medical therapy fails. This is performed via posterolateral thoracotomy, and typically a clip is placed on the PDA vs. suture ligation and division. Surgical PDA ligation is essentially 100% effective and is typically performed safely when done by experienced operators. However, the procedure is not without risk, and complications include vocal cord paralysis, pneumothorax, diaphragm paralysis, and postligation cardiac syndrome. Much of the morbidity and mortality of PDA surgical liga-tion is related to the preoperative clinical status of the



lines for prolonged periods of time. This is the reason there is a high prevalence of venous and arterial occlusion in the congenital heart disease population, especially in those with functional single ventricle heart conditions. The importance of obtaining umbilical venous and arterial access imme-diately after birth cannot be emphasized enough. Studies have shown that single ventricle patients who have umbili-cal venous lines placed instead of femoral lines have had significantly lower complication rates of vascular throm-bosis and occlusion.1 Furthermore, these patients require multiple catheterization procedures in their lifetime, and occluded femoral veins or arteries complicate these proce-dures considerably and can make some future interventions impossible to perform. If nonumbilical access is required, practice is to use the smallest catheter necessary for medical management. Use of single lumen instead of double lumen results in less vascular occlusion. Tunneling central lines is associated with less thrombosis and a decreased rate of central line–associated blood stream infections. Placement of catheters in the upper extremities or neck vessels is not recommended in single ventricle patients prior to the Fontan operation. If catheters are necessary in these posi-tions, anticoagulation should be administered immediately after placement, and the line should be removed as soon as it is safely possible to reduce the risk of vascular stenosis or occlusion. Finally, when other alternative sites of access have been exhausted, transhepatic lines can be placed in the catheterization laboratory and have been shown to be a feasible and safe alternative in infants with otherwise limited access.41

Pericardiocentesis

Pericardiocentesis or pericardial drain placement can be safely performed in the neonate. The procedure is typi-cally guided by transthoracic echocardiogram but can be performed by landmark alone in emergency cases when the patient is suffering from cardiac tamponade. There are mul-tiple causes for tamponade, but in the neonate one of the most common causes is associated with indwelling central venous catheters. It is not known whether the mechanism of tamponade is perforation or simple diffusion across a very thin atrial wall, but analysis of the effusion often shows similar fluid composition to the infusate.62

Fetal Cardiac Intervention

Fetal cardiac intervention (see Chapter 13) has been the subject of much interest over the past 10 years. Its use is attractive in some of the congenital cardiac defects with poor outcomes secondary to valvar obstructions, which can lead to ventricular hypoplasia. There are currently three catheter-based interventions that have been performed in fetuses with congenital heart disease: balloon valvuloplasty in aortic valve stenosis (with impending hypoplastic left heart syndrome), balloon valvuloplasty in pulmonary atresia with intact ventricular septum (with impending hypoplastic

stenosis is poorly understood but appears inflammatory or sclerosing in nature. There have been some reports of suc-cessful outcomes using drug-eluting stents and balloons to attempt to reduce or halt the inflammatory process.42

There are few neonatal cardiac surgeries that need to be performed emergently, as medical or catheter-based therapies can usually allow more time for adequate diagnostic imaging and screening. An exception to this is obstructed total anom-alous pulmonary venous return, wherein pulmonary venous blood does not have an adequate egress. This leads to pul-monary edema and severe pulmonary hypertension. Respira-tory failure quickly develops, followed by a drop in cardiac output caused by profound cyanosis and sequestered pul-monary venous blood from the heart. Stenosis of a vein that drains pulmonary venous flow in total anomalous pulmonary venous return (i.e., vertical vein) can be stented to stabilize or palliate the patient until a surgical repair can be performed.29 Surgical treatment of obstructed total anomalous pulmonary venous return is described in the next section.

Surgical Repair of Total Anomalous Pulmonary Venous Return

Total anomalous pulmonary venous return (TAPVR) is an embryologic failure of fusion of the confluence of the pulmo-nary veins to the adjacent left atrium. The pulmonary venous return finds its way back to the heart via a communicating vein in one of four ways: 1) supracardiac—is the most common, whereby the confluence of the pulmonary veins drain into an ascending vertical vein that connects to the innominate vein then the superior vena cava; 2) infracardiac—has a descend-ing vertical vein draining into the portal vein or inferior vena cava; 3) cardiac—has a direct communication from the confluence to the coronary sinus; and 4) mixed— is the least common and has some combination of the previous three. If there is any obstruction or stenosis of this communicating pathway, profound cyanosis and hemodynamic compromise rapidly ensues, creating a surgical emergency. Often these newborns are in crisis before a diagnosis is made, winding up on ECMO support without a clear etiology. Once on ECMO, the diagnosis may be more difficult to make by echocardiography; therefore, the treating clinicians need to maintain a high index of suspicion for TAPVR, sometimes requiring advanced imaging or catheterization to confirm the diagnosis. The surgical repair of TAPVR is done via a median sternotomy on cardiopulmonary bypass. The principles of the operation include direct anastomosis of the anterior wall of the confluence of the pulmonary veins to the posterior wall of the adjacent left atrium as well as ligation of the communicat-ing vein. Typically, a PFO or small atrial septal defect is left to help the management of potential postoperative pulmonary hypertensive events.

Central Line Placement

Neonates with congenital heart disease often require indwelling central venous catheters and arterial monitoring



approaches. The Hybrid Stage 1 procedure is performed via a median sternotomy, without cardiopulmonary bypass, whereby bilateral branch pulmonary artery bands are placed and a PDA stent is inserted. A balloon atrial septostomy (BAS) can be performed at the same time using a hybrid transatrial approach or standard percutaneous femoral approach, or the BAS can be performed several days later in the cardiac catheterization lab. Serial echocardiography is used to assess for obstruction at the atrial septum, through the PDA stent, or restriction to antegrade or retrograde flow in the transverse aortic arch. Any sign of obstruction and/or worsening right ventricular function or worsening tricuspid valve regurgitation warrants a cardiac catheterization. Any obstruction can almost always be successfully treated in the cardiac catheterization lab with return to baseline function.

Shunt Obstruction

One of the most feared complications of systemic to pul-monary artery shunts is complete or near complete shunt occlusion in patients dependent solely on the shunt for pulmonary blood flow. When severe cyanosis develops sec-ondary to shunt obstruction, the two treatment strategies include surgical revision or transcatheter intervention. If possible, this is best dealt with in the cardiac catheterization lab to avoid another midline sternotomy. In the event of complete occlusion, patients sometimes need to be stabi-lized on extracorporeal membrane oxygenation (ECMO) to provide adequate oxygenation and then can be transported to the cardiac catheterization lab. Transcatheter interven-tions include simple balloon dilation, thrombus evacuation, or stent implantation within the shunt (Fig. 78.8A, B).28 Interventions for modified Blalock-Taussig shunt obstruc-tions are usually approached from the femoral artery. RV-PA (Sano) shunts are typically approached from the femoral

right ventricle), and atrial septal defect creation or enlarge-ment in hypoplastic left heart syndrome with restrictive or intact atrial septum. Fetal cardiac interventions are not per-formed as standard of care at all heart centers and are typi-cally only performed at centers with experienced teams made up of high-risk OB (maternal-fetal medicine), fetal cardiology, and interventional cardiology. As such, it is common for centers who do not offer the procedure to refer patients to one of the experienced centers. There is a non-insignificant risk to the fetus and potentially the mother, so candidates for fetal cardiac intervention must be carefully screened and vetted before the decision to proceed is made. Accurate diagnosis and referral for intervention must be made early enough in gestation to allow for potential rever-sal of disease progression following. Lastly, information regarding the natural history of these defects is not com-pletely understood, making it difficult to predict which fetus will develop ventricular hypoplasia and should undergo these high-risk fetal interventions.34 The mortality associ-ated with these procedures is improving as experience is gained. Nevertheless, it is still not clear-cut that early fetal intervention will consistently alter disease progression beyond the watchful waiting and treating the high risk neonate with established strategies.36

Hybrid Stage I Palliation

The hybrid approach has emerged as an alternative treatment strategy for the management of hypoplastic left heart syn-drome (HLHS) and other complex neonatal heart anoma-lies beginning in the early 1990s.19,54 The term hybrid refers to procedures performed, during which a combination of surgical and interventional methods are utilized. Because published medium-term results of the hybrid procedure demonstrated outcomes comparable to surgical palliation, this alternative approach was adopted by many more insti-tutions.18 The initial palliation with a Hybrid Stage 1 pro-cedure is performed without the use of cardiopulmonary bypass and typically includes three steps: 1) bilateral branch pulmonary artery bands that protect the lungs from persis-tent high pressure and flow, while balancing the pulmonary versus systemic circulations 2) a stent in the patent ductus arteriosus (PDA) to assure unobstructed systemic blood flow; and 3) atrial balloon septostomy, or rarely stenting, to assure unrestricted flow from the left atrium to the right atrium (Fig. 78.7). This Hybrid Stage 1 palliation has been used successfully in patients with standard risk factors, those with a high-risk profile, as a tool for salvage, as a bridge to heart transplantation, and as a bridge to a two-ventricle repair. All forms of HLHS have been successfully palliated with a Hybrid Stage 1 procedure including aortic atresia/mitral atresia with a diminutive ascending aorta. More-over, neither patient size nor prematurity have proven to be a contraindication to using this strategy nor has sig-nificant associated co-morbidities. That is why the Hybrid Stage 1 is used in many centers for their high-risk patients with known poor outcomes with more traditional surgical

• Fig. 78.7 Artistic depiction of a Hybrid Stage I palliation from the surgical view. Surgical bands have been placed on the bilateral branch pulmonary arteries. The main pulmonary artery is directly accessed above the pulmonary valve and a stent has been implanted along the entire length of the ductus arteriosus (from branch pulmonary arteries to the descending aorta).



risk of life-threatening infections. The cumulative risk of graft failure secondary to cardiac allograft vasculopathy is 50% at 15 years. Unfortunately, despite the ability to perform re-transplantations for graft failure, both patient and graft survival are less compared to primary transplanta-tion. Therefore, considering a lifelong management strategy for newborn congenital heart disease transplantation needs to be reserved for those without other options. Nonetheless, in neonates that require transplantation there are ongoing efforts to expand the donor supply, for example, by consid-ering donation from anencephalic donors. Also, the ability to successfully perform ABO-incompatible heart transplan-tation is unique in the neonate by taking advantage of their somewhat naïve immunologic response to antigens.65

Medical Management

Prostaglandin E1

In infants with a known prenatal diagnosis of ductal-dependent CHD, prostaglandin E1 (PGE1) infusion should be initiated shortly after birth and after intravenous access is obtained. For infants in whom ductal-dependent CHD is suspected based on cyanosis or shocklike clinical picture, PGE1 infusion should also be initiated immediately and continued until further testing, usually an echocardiogram, can be performed to either confirm or negate the diagnosis. In these undiagnosed clinical situations, prompt initiation of PGE1 is critical and can be lifesaving. PGE1 can be infused through virtually any vascular access that can be obtained, including the intraosseous route. The standard dose for maintenance of ductal patency is 0.03 mcg/kg/min. For infants with suspected ductal-dependent CHD who present with severe cyanosis or shock, an initial dose

vein.48 For partial or near occlusion, these procedures carry a high risk, as crossing the already obstructed shunt further decreases the diminutive pulmonary blood flow and can lead to severe cyanosis and cardiac arrest. Nevertheless, when performed by experienced operators the success rate is encouraging and surgical revision is rarely required.

Neonatal Heart Transplantation

Heart transplantation in the neonate continues to be reserved for those babies with congenital cardiac anomalies or cardiomyopathies that are not amenable to repair. Even high-risk single ventricle conditions such as hypoplastic left heart syndrome are rarely treated primarily with heart transplantation. The reasons for this are many, as high-lighted in the 2017 report of the International Society for Heart and Lung Transplantation.8 The number of infant (<1 year old) heart transplantations performed in North America and Europe combined has been stable for years at only about 120 per year. Not only is this a reflection of the limited indications for transplantation, but more importantly it reflects the severely limited donor pool of this rare resource. Patient survival is about 75% at 8 years and 50% at 22 years, which is somewhat better than reported results for older children.26 Reasons for the improved sur-vival rate include the immaturity of the immune system leading to decreased antibody-mediated rejection. In addi-tion, neonatal transplant patients have been shown to have less graft vasculopathy68 and require less immune suppres-sion.25 However, there are lifelong challenges with immuno-suppression and the balance of rejection and infection that lead to a continuous risk hazard of significant morbidities. The continuous risk of developing a malignancy is 10% at 10 years, primarily lymphomas as well as the continuous

BA

• Fig. 78.8 Stent implantation within a modified Blalock-Taussig shunt. A selective angiogram shows a stenotic shunt with poor filling of the left pulmonary artery (A). Following stent implantation, there is improved diameter of the shunt and improved filling of the left pulmonary artery (B).



and measures are not taken to counterbalance this change in physiology, systemic perfusion can become inadequate and end organ injury (acute renal insufficiency, necrotizing enterocolitis) can result. This condition termed “pulmonary overcirculation/systemic hypoperfusion” can happen after even a very short period of time in the preoperative period. As such, regular checks of arterial blood gases (preferably) or capillary gases can provide significant insight into the balance of circulations. Elevation in arterial lactate levels can precede clinical instability and end organ injury, so it is recommended to follow and trend these levels serially. In general, pH should be maintained at 7.34-7.40 and alkalosis should be avoided. The Pco2 and serum bicar-bonate levels are less reliable to follow, especially when the neonate is receiving diuretics, because of the contrac-tion alkalosis these medications can cause. If pH is main-tained in this range, most patients will not overcirculate to a significant degree. In nonintubated neonates, relative overcirculation can lead to hyperventilation, and respira-tory rates in the 80s to 90s are not uncommon. In these situations, the neonate may develop hypocapnia, leading to alkalosis and worsening pulmonary overcirculation. When these situations arise, it is sometimes necessary to intubate and assume control of the ventilation by dropping rate and minute ventilation until the pH is back into the desired range.

Oxygen, particularly alveolar or delivered oxygen, is a potent pulmonary vasodilator. The administration of sup-plemental oxygen can lead to dramatic drops in PVR and increasing pulmonary blood flow. In general, supplemental oxygen should be avoided in single ventricle patients, espe-cially HLHS, unless there is significant lung disease leading to suspected pulmonary venous desaturation in which satu-rations are consistently less than 70%. On the contrary, in patients with high saturations from pulmonary overcir-culation, it is sometimes necessary to provide subambient levels of oxygen, which raises the PVR and “discourages” pulmonary blood flow. Subambient oxygen can be admin-istered by bleeding in nitrogen gas into a ventilation tent or through the endotracheal tube in an intubated infant. An FiO2 of 18%-20% can be effective at raising PVR, but close monitoring of oxygen saturations and PaO2 is necessary if this therapy is pursued.

Blood Products

Infants with cyanotic congenital heart disease often have deficient oxygen delivery to vital tissue and organs because of the high levels of fetal hemoglobin and its high oxygen affinity. Therefore it is important to maximize the oxygen-carrying capacity in these patients, and studies have shown that increasing the hemoglobin to >13 gm/dL or hematocrit to >40% is ideal. This can be accomplished in the short term by transfusing packed red blood cells (15-20 cc/kg) or over a longer period of time by administering weekly eryth-ropoietin injections.45 The exposure to many different blood donors can lead to antigen sensitization and make future

of 0.1 mcg/kg/min is often a recommended starting dose to open the ductus arteriosus. This dose can be increased in certain situations to 0.2 mcg/kg/min if the ductus arterio-sus remains closed at the 0.1 mcg/kg/min dose. Conversely, the dose can often be decreased back to a maintenance dose of 0.03 mcg/kg/min once the ductus arteriosus is reopened and the infant has begun to stabilize clinically. The short-term side effects of PGE1 include apnea/hypopnea, skin flushing, and fever, and these tend to be dose-dependent effects.24 If side effects are occurring and causing manage-ment issues, the dose can be titrated down to as low as 0.01 mcg/kg/min as long as the ductus arteriosus remains patent and an adequate size at that level. There is no limit for how long PGE1 can be infused, and sometimes it is nec-essary to maintain an infant on PGE1 for prolonged periods of time, especially for those infants with significant medical co-morbidities or extreme prematurity. As stated in the previous sections, the alternative for prolonged PGE1 infu-sion is implanting a ductal stent to maintain patency and, therefore, avoid the long-term effects of PGE1, including periosteal hyperostosis15 or gastric outlet obstruction.30,49

Oxygen and Ventilation

Most patients with mild and moderate forms of congenital heart disease do not require special consideration regard-ing oxygen therapy and ventilation strategies. They can typically be managed following standard neonatal strategies appropriate for age and size. Patients with single ventricle physiology and some with two ventricles who will require a PDA for ductal-dependent CHD require more specific management strategies to maintain pH levels within tighter ranges and judicious use of delivered oxygen. Neonates with single ventricle heart conditions in which the systemic and pulmonary circulations are connected by the PDA have oxygenation, cardiac output, and tissue perfusion that is extremely dependent on relative changes in the vascular resistances. As the pulmonary vascular resistance drops over the first week, keeping an appropriate balance of circula-tions becomes more difficult and close attention to arterial blood gas parameters becomes increasingly important. The most exemplary situation when ventilation and supple-mental oxygen therapy can affect the balance between the systemic and the pulmonary vascular beds is in the care of infants with hypoplastic left heart syndrome.2 Preopera-tively, systemic output is dependent on right-to-left flow across the PDA, which is typically maintained by PGE1. When pulmonary vascular resistance (PVR) is high, blood flow through the PDA is right-to-left in systole as well as during a portion of diastole. As such, oxygen saturations will be relatively low because of relatively reduced amounts of pulmonary blood flow, and systemic perfusion will be adequately maintained. As the PVR falls during the first day to week of life, blood flow remains right-to-left in systole across the PDA but becomes left-to-right in all of diastole, resulting in rising oxygen saturations with increas-ing pulmonary blood flow. If the PVR falls significantly



and vasoactive agents. Often, medication drips or hyper-alimentation can be concentrated or even discontinued if not immediately critical. Urine output can be maximized by maintaining good cardiac output and the aggressive use of diuretics. First-line diuretic therapy is generally a loop diuretic such as furosemide or bumetanide, often used in combination with a thiazide diuretic such as chlorothiazide for potentiation of effect. Hypokalemia is common with higher doses of loop diuretics, and patients may require either potassium supplementation or a potassium-sparing diuretic such as spironolactone (which also has beneficial ventricular remodeling properties) to avoid the hypoka-lemic hypochloremic metabolic alkalosis associated with long-term diuretic therapy.

Besides the postoperative period, it is common for patients with lesions resulting in pulmonary overcircula-tion (left-to-right shunts) to become fluid overloaded and need diuretic therapy. Although the pulmonary vascular resistance is still somewhat elevated and may temporarily protect the patient from overcirculation, certain lesions, such as a large patent ductus arteriosus, unrestrictive ven-tricular septal defects, certain forms of truncus arteriosus, and large aortopulmonary collaterals will result in excessive pulmonary blood flow, and diuretics will almost certainly be required prior to neonatal surgical repair.

In other situations, it may be beneficial to keep the patient relatively fluid loaded but not overloaded. For example, in patients with RVOT obstruction, such as tetralogy of Fallot, subpulmonary obstruction is somewhat dynamic, and a pre-loaded right ventricle can help to keep these patients from having hypercyanotic spells. A volume-loaded right ven-tricle will physically stretch or distend the subpulmonary area thereby decreasing the amount of dynamic collapse that leads to limited pulmonary blood flow and cyanosis. Similarly, patients with certain forms of cardiomyopathy will have stiff, noncompliant ventricles with significant diastolic dysfunction. These patients also need to have adequate preload to maintain ventricular filling and stroke volume.

Afterload

Afterload refers to the cumulative pressure against which the systemic ventricle must work to eject blood during systole. Although systemic blood pressure makes up the most sig-nificant portion of the afterload, the condition of the ven-tricle (wall stress and preload) must also be considered. For example, in a healthy heart with normal systolic and dia-stolic ventricular function, increasing afterload can be over-come by the ventricle by increasing ventricular wall stress and contractility. If the high afterload is chronic, myocardial hypertrophy will develop to assist the ventricle in overcom-ing this stress. However, in a dysfunctional ventricle the capacity to overcome acute and chronically elevated after-load is not as robust. In this situation, high afterload leads to higher systolic pressures and wall stress, which then leads to rising filling pressures and atrial hypertension. Although

matches for cardiac transplantation difficult. Furthermore, excessive use of packed red blood cell transfusions has been linked to transfusion-related acute lung injury (TRALI), prolonged length of ICU stay, increased risk of infection, and higher mortality. Therefore, neonatal transfusions should be used only when absolutely necessary for optimiz-ing clinical status. Platelet transfusions are uncommon in the preoperative state in neonatal patients with CHD. The presence of thrombocytopenia in neonatal CHD is likely related to other perinatal pathophysiology and unlikely related to the cardiac diagnosis. Usual replacement practices should be followed by the neonatology team in these cases. Similarly, the need for fresh frozen plasma, cryoprecipitate, or other factor replacement is rare in the preoperative state for neonates with CHD. Postoperatively, however, the need for platelets and plasma is common and usually directed by the cardiothoracic intensive care unit (CTICU) team or cardiac intensivists to address postoperative bleeding and to optimize oxygen delivery.

Preload

Preload or the overall volume status of neonates is often very difficult to assess because of the tendency for capillary leak and the third-spacing of fluid. For neonates with congenital heart disease, especially those with fetal hydrops or those who develop edema shortly after birth, trying to assess and optimize preload can be extremely difficult. However, pre-venting fluid overload when hypotension is present and withholding fluid when the neonate appears edematous from third-spacing in the presence of end organ hypo-perfusion are management decisions that have potential for tremendous impact on the overall course for neonates requiring complex operations. Profound fluid overload has been correlated with increased duration of mechanical ven-tilation, prolonged ICU times, and delayed recovery of kidney function. These situations can develop even in the absence of concomitant conditions such as atrioventricular or semilunar valve dysfunction, hypoalbuminemia, anemia, and sepsis, which can all make assessments and treatment decisions that much more complex and difficult. Therefore, it is crucial that the management teams pay close attention to daily weights, input/output totals, clinical exam findings such as liver span and fullness of fontanelle, and electrolytes and renal function (BUN and creatinine) on a daily if not shift basis. Teams must take the entirety of information into account to decide if fluid restriction or resuscitation is required.

There are specific times when fluid management tech-niques may differ from simply attempting to achieve euvolemia. In the postoperative period, edema is extremely common because of fluid received in the operating room, capillary leak syndrome associated with cardiopulmonary bypass, and the need for perioperative blood products. In an attempt to combat this fluid overload, crystalloid or colloid administration should be used judiciously while maximizing the cardiac output with the use of inotropic



milrinone is commonly used in the postoperative period because of its improved inotropy, lusitropy, and afterload-reducing effects.

Treatment of Hypercyanotic Spells

Hypercyanotic spells or “tet spells” are acute episodes that can develop in patients with tetralogy of Fallot when there is dynamic subpulmonary obstruction of the right ventricular outflow tract. When acute worsening of RVOT obstruction develops, there is a significant decrease in pulmonary blood flow and subsequent shunting of blood right to left at the ventricular level leading to severe hypoxia and cyanosis. The infundibulum of the right ventricle is thought to be reactive to circulating catecholamines, which increase with increasing patient agitation, resulting in increased gradient across the RV outflow tract forcing deoxygenated blood across the ventricular septal defect into the aorta, resulting in cyanosis. Other factors such as decreased right ventricular filling owing to relative hypovolemia and lack of preload or tachycardia may further predispose these patients to hyper-cyanotic episodes. The treatment for hypercyanotic episodes is to find ways to decrease the subpulmonary obstruction, encourage more pulmonary blood flow, and increase the relative degree of left to right shunting at the ventricular level. If these maneuvers are followed, hypercyanotic spells can often be treated quickly before the infant is hypoxic for an unsafe amount of time. Some of these maneuvers and the physiologic rationale for their use are illustrated in Table 78.5.

What the Future Holds

The field of congenital heart disease is constantly changing and innovation is typically the rule and not the exception. The past 20 years have seen a tremendous improvement in the medical, surgical, and interventional therapies for neonates and children with congenital heart disease. Fortu-nately, through the fervent work of many individuals and organizations (www.pediatricdeviceconsortium.org; www .pediaworks.org), the FDA became more aware of these limitations in the treatment of children and in 2007 passed the Pediatric Medical Device Safety and Improvement Act. The PMDSIA was the first major legislation ever exclusively directed toward pediatric devices and has already stimulated innovation, provided new incentives for pediatric device development, and allowed for better safety monitoring of devices. In 2012, the PMDSIA was renewed by congress and additional funding for the Pediatric Device Consor-tium Grant Program was secured.

Pediatric Interventional Cardiology has benefitted recently from the approval of two transcatheter pulmonary valves: Medtronic’s Melody Transcatheter Pulmonary Valve in 2010 and the Edwards Sapien XT Transcatheter Heart Valve for Pulmonic Indications in 2016. The first FDA-approved stent for coarctation of the aorta was approved in 2016 after an extensive investigation of the NuMED

fluid resuscitation may allow for maintained cardiac output over a short period of time, fluid overload may ensue and other measures are required to assist the diseased ventricle. Oral afterload-reducing agents are typically antihyperten-sive medications that lower systemic vascular resistance and systemic blood pressure. Although medications like angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB) do provide long-term ventricular remodeling effects, in the short term they only affect afterload by the blood-pressure-lowering effects. For critically ill neonates, these medications are rarely used. The medication most commonly utilized for this situation is milrinone, which has afterload-reducing, inotropic, and lusitropic (ventricular relaxing) properties. The net effect of milrinone is to have improved ventricular filling, improved stroke volume, and lower afterload for overall increase in cardiac output. Dobutamine has similar effects but usually results in significantly elevated heart rate. For neonates that have much higher resting heart rate, the tachycardia of dobutamine makes it less desirable compared to milrinone. Nitroprusside infusion is rarely used in neonates as it is a potent vasodilator and afterload-reducing agent but lacks the inotropic and lusitropic properties of milrinone. The relatively low blood pressure of most neonates does not lend itself to treatment by this drug on a regular basis.

To reduce afterload in the subpulmonary ventricle, any agent that selectively decreases pulmonary vascular resis-tance can be considered in neonates. Oxygen and inhaled nitric oxide are potent pulmonary vasodilators and reduce pulmonary afterload very well. Other agents (sildenafil or bosentan) used to treat pulmonary hypertension can be considered for use under the guidance of pediatric pulmo-nary hypertension experts.43

Contractility

Agents that increase inotropy and cardiac contractility can improve cardiac output. A commonly used oral agent to increase contractility is digoxin, which has been shown to be safe in the neonate with left ventricular volume overload and systolic dysfunction.21 However, this oral medication is rarely used in the neonatal period solely for the purpose of treating ventricular systolic dysfunction or heart failure unless added to a regimen that includes afterload-reducing agents and diuretics, as it is typically a secondary or tertiary agent.

Intravenous inotropic support is more commonly encountered in the neonatal period to treat perinatal, preop-erative, and postoperative systolic dysfunction.44 Dopamine and dobutamine have similar inotropic effects, although dopamine is usually preferred because of its greater effect in premature infants and because it causes less tachycardia and systemic vasodilation than dobutamine. Epinephrine is used in low doses for its inotropic effect, although coun-terintuitive effects of increasing myocardial oxygen demand through increased heart rate and systemic vascular resistance can limit its use. As discussed in the afterload section,


http://www.pediatricdeviceconsortium.org/

http://www.pediaworks.org/

http://www.pediaworks.org/


inhibit access to a particular area of the heart. Catheters are also being made smaller and more versatile to avoid some vascular complications that occurred using adult-sized equipment in children.

We are also becoming more organized in the way we share information. Patient populations are too heteroge-neous to be able to provide good, large-scale evidence for the therapies provided. Multi-institutional and even multinational registries (IMPACT, CCISC, C3PO, NPC/QIC, etc.) are now allowing compilation of more useful data than ever before and will certainly be sources of solid evidence-based studies in the future. This will allow the field to advance, given that only 2% of the 2011 AHA recommendations on cardiac catheterization in children are level of evidence A.16

Cheatham Platinum (CP) Stent System. Although these valves and stents are not currently for use via typical trans-catheter route in neonates and infants, the miniaturization of this technology is underway so that more infants will be candidates for hybrid implants in the near future. Further-more, devices used for transcatheter occlusion of PDAs are currently being studied for their use in the premature infant population, and the first occluder, Piccolo (Abbott Medical) has just been approved by the FDA.

Biodegradable materials and devices remain one of the most important focuses of research and are at the forefront of innovation in pediatrics because of the ideal potential to allow placement or implantation of a device that would eventually resorb or degrade and not inhibit growth of the vessel or heart structure in which it has been placed or

Treatment of Cyanotic Episodes Rationale/Physiologic Effect(s)

100% oxygen Decreases PVR and improves oxygen delivery

Knees to chest Increases SVR and preload

Manual compression of abdominal aorta Increases SVR

Nonprovocation Decreases catecholamines and infundibular spasm

Fluid bolus (0.9% saline, 5% albumin, blood), 10-20 mL/kg Increases RV preload

Morphine, 0.1-0.2 mg/kg IV/IM/SC Decreases catecholamines and infundibular spasm

Ketamine, 0.4-1 mg/kg IV/IM Decreases catecholamines and infundibular spasm

Fentanyl, 1-4 mcg/kg IV/IM/SC Decreases catecholamines and infundibular spasm

Phenylephrine, 5-20 mcg/kg IV bolus or IV infusion 0.1-0.5 mcg/kg/min, 0.1 mcg/kg SC/IM

Increases SVR

Propranolol, 0.05-0.15 mg/kg slow IV Increases RV filling and decreases catecholamines

IM, Intramuscular; IV, intravenous; PVR, pulmonary vascular resistance; RV, right ventricular; SC, subcutaneous; SVR, systemic vascular resistance.

Treatment Strategies and Physiologic Rationale for Hypercyanotic Episodes Associated With Tetralogy of Fallot

TABLE 78.5

Key Points• Neonates with congenital heart disease require a well-

integrated and multidisciplinary team approach to achieve optimal outcomes.

• The vastmajority of congenital heart disease does notrequire specific neonatal management.

• Moderate to severely complex congenital heart condi-tions can be classified into cyanotic and acyanotic forms.

• Cyanotic congenital heart disease includes conditionswith too little pulmonary blood flow and excessive pul-monary blood flow.

• Surgicalmethods to increasepulmonarybloodflow incyanotic CHD include surgical systemic-pulmonary artery shunts and surgically opening the right ventricular outflow tract.

• Interventional methods to increase pulmonary bloodflow include PDA stenting and RVOT stenting.

• Themost reliable approach to limit pulmonary bloodflow is placement of a main pulmonary artery band.

• Numerousmethods exist to improvemixing at the atriallevel in conditions such as transposition of the great arteries.

• Inpremature infants,PDAclosure canbedonemedi-cally, surgically, and now via interventional approach with small vascular plugs.

• Prompt initiation of PGE1 infusion in patients withsuspected ductal-dependent CHD who present with cya-nosis or shocklike picture can be a life-saving treatment.



References1. Aiyagari R, Song JY, Donohue JE, et al. Central venous catheter-

associated complications in infants with single ventricle: com-parison of umbilical and femoral venous access routes. Pediatr Crit Care Med. 2012;13(5):549–553.

2. Alghamdi AA, Baliulis G, Van Arsdell GS. Contemporary manage-ment of pulmonary and systemic circulations after the Norwood procedure. Expert Rev Cardiovasc Ther. 2011;9(12):1539–1546.

3. Backes CH, Kennedy KF, Locke M, et al. Transcatheter occlusion of the patent ductus arteriosus in 747 infants <6 kg: insights from the NCDR IMPACT registry. JACC Cardiovasc Interv. 2017; 10(17):1729–1737.

4. Balasubramanian S, Marshall AC, Gauvreau K, et al. Outcomes after stent implantation for the treatment of congenital and post-operative pulmonary vein stenosis in children. Circ Cardiovasc Interv. 2012;5(1):109–117.

5. Baylen BG, Grzeszczak M, Gleason ME, et al. Role of balloon atrial septostomy before early arterial switch repair of transposition of the great arteries. J Am Coll Cardiol. 1992;19(5):1025–1031.

6. Bendaly EA, Lane KA, Breinholt JP. Balloon angioplasty of reco-arctation of the neoaortic arch after the Norwood operation: factors affecting outcome and recurrence. Catheter Cardiovasc Interv. 2013;81(1):97–102.

7. Boe BA, Zampi JD, Kennedy KF, et al. Acute success of balloon aortic valvuloplasty in the current era: a National Cardiovas-cular Data Registry study. JACC Cardiovasc Interv. 2017; 10(17):1717–1726.

8. Chambers DC, Yusen RD, Cherikh WS, et al. The Registry of the International Society for Heart and Lung Transplanta-tion: thirty-fourth adult lung and heart-lung transplantation report—2017; focus theme: allograft ischemic time. J Heart Lung Transplant. 2017;36(10):1047–1059.

9. Cheatham JP. Intervention in the critically ill neonate and infant with hypoplastic left heart syndrome and intact atrial septum. J Interv Cardiol. 2001;14(3):357–366.

10. Cools B, Boshoff D, Heying R, et al. Transventricular balloon dilation and stenting of the RVOT in small infants with tetral-ogy of Fallot with pulmonary atresia. Catheter Cardiovasc Interv. 2013;82(2):260–265.

11. Devanagondi R, Peck D, Sagi J, et al. Long-term outcomes of balloon valvuloplasty for isolated pulmonary valve stenosis. Pediatr Cardiol. 2017;38(2):247–254.

12. Dohlen G, Chaturvedi RR, Benson LN, et al. Stenting of the right ventricular outflow tract in the symptomatic infant with tetralogy of Fallot. Heart. 2009;95(2):142–147.

13. Drossner DM, Kim DW, Maher KO, Mahle WT. Pulmonary vein stenosis: prematurity and associated conditions. Pediatrics. 2008;122(3):e656–e661.

14. Elder RW, Quaegebeur JM, Bacha EA, et al. Outcomes of the infant Ross procedure for congenital aortic stenosis followed into adolescence. J Thorac Cardiovasc Surg. 2013;145(6):1504–1511.

15. Estes K, Nowicki M, Bishop P. Cortical hyperostosis secondary to prostaglandin E1 therapy. J Pediatr. 2007;151(4):441, 441 e441.

16. Feltes TF, Bacha E, Beekman RH 3rd, et al. Indications for cardiac catheterization and intervention in pediatric cardiac disease: a scientific statement from the American Heart Associa-tion. Circulation. 2011;123(22):2607–2652.

17. Forbes TJ, Kim DW, Du W, et al. Comparison of surgical, stent, and balloon angioplasty treatment of native coarctation of the aorta: an observational study by the CCISC (Congenital Cardiovascular

Interventional Study Consortium). J Am Coll Cardiol. 2011; 58(25):2664–2674.

18. Galantowicz M, Cheatham JP, Phillips A, et al. Hybrid approach for hypoplastic left heart syndrome: intermediate results after the learning curve. Ann Thorac Surg. 2008;85(6):2063–2070, discus-sion 2070–2061.

19. Gibbs JL, Wren C, Watterson KG, et al. Stenting of the arterial duct combined with banding of the pulmonary arteries and atrial septectomy or septostomy: a new approach to palliation for the hypoplastic left heart syndrome. Br Heart J. 1993;69(6):551–555.

20. Haas NA, Laser TK, Moysich A, et al. Stenting of the right ventricular outflow tract in symptomatic neonatal tetralogy of Fallot. Cardiol Young. 2014;24(2):369–373.

21. Hastreiter AR, van der Horst RL, Voda C, Chow-Tung E. Main-tenance digoxin dosage and steady-state plasma concentration in infants and children. J Pediatr. 1985;107(1):140–146.

22. Herbert CE, Veeram Reddy S, Welch TR, et al. Bench and initial pre-clinical results of a novel 8 mm diameter double opposed helical bio-degradable stent. Catheter Cardiovasc Interv. 2016;88(6):902–911.

23. Holzer RJ, Wood A, Chisolm JL, et al. Atrial septal interven-tions in patients with hypoplastic left heart syndrome. Catheter Cardiovasc Interv. 2008;72(5):696–704.

24. Huang FK, Lin CC, Huang TC, et al. Reappraisal of the prostaglandin E1 dose for early newborns with patent ductus arteriosus-dependent pulmonary circulation. Pediatr Neonatol. 2013;54(2):102–106.

25. Ibrahim JE, Sweet SC, Flippin M, et al. Rejection is reduced in thoracic organ recipients when transplanted in the first year of life. J Heart Lung Transplant. 2002;21(3):311–318.

26. John M, Bailey LL. Neonatal heart transplantation. Ann Cardio-thorac Surg. 2018;7(1):118–125.

27. Kan JS, White RI Jr, Mitchell SE, Gardner TJ. Percutaneous balloon valvuloplasty: a new method for treating congenital pulmonary-valve stenosis. N Engl J Med. 1982;307(9):540–542.

28. Krasemann T, Tzifa A, Rosenthal E, Qureshi SA. Stenting of mod-ified and classical Blalock-Taussig shunts—lessons learned from seven consecutive cases. Cardiol Young. 2011;21(4):430–435.

29. Kyser JP, Bengur AR, Siwik ES. Preoperative palliation of newborn obstructed total anomalous pulmonary venous con-nection by endovascular stent placement. Catheter Cardiovasc Interv. 2006;67(3):473–476.

30. Lacher M, Schneider K, Dalla Pozza R, Schweinitz DV. Gastric outlet obstruction after long-term prostaglandin administration mimicking hypertrophic pyloric stenosis. Eur J Pediatr Surg. 2007;17(5):362–364.

31. Latson LA, Fleming WH, Hofschire PJ, et al. Balloon valvuloplasty in pulmonary valve atresia. Am Heart J. 1991;121(5):1567–1569.

32. Leonard GT Jr, Justino H, Carlson KM, et al. Atrial septal stent implant: atrial septal defect creation in the management of complex congenital heart defects in infants. Congenit Heart Dis. 2006;1(3):129–135.

33. Mahmoud HT, Santoro G, Gaio G, et al. Single-center experi-ence in percutaneous closure of arterial duct with Amplatzer duct Occluder II additional sizes. Catheter Cardiovasc Interv. 2017;89(6):1045–1050.

34. Makikallio K, McElhinney DB, Levine JC, et al. Fetal aortic valve stenosis and the evolution of hypoplastic left heart syn-drome: patient selection for fetal intervention. Circulation. 2006;113(11):1401–1405.

35. Marasini M, Gorrieri PF, Tuo G, et al. Long-term results of catheter-based treatment of pulmonary atresia and intact ven-tricular septum. Heart. 2009;95(18):1520–1524.



53. Raval A, Thakkar B, Madan T, et al. Ductus arteriosus stent-ing: a promising percutaneous palliation in patients with duct-dependent pulmonary circulation. Rev Port Cardiol. 2016; 35(11):583–592.

54. Ruiz CE, Gamra H, Zhang HP, et al. Brief report: stenting of the ductus arteriosus as a bridge to cardiac transplantation in infants with the hypoplastic left-heart syndrome. N Engl J Med. 1993;328(22):1605–1608.

55. Sandoval JP, Chaturvedi RR, Benson L, et al. Right ventricular outflow tract stenting in tetralogy of Fallot infants with risk factors for early primary repair. Circ Cardiovasc Interv. 2016;9(12).

56. Sathanandam S, Justino H, Waller BR 3rd, et al. Initial clinical experience with the Medtronic micro vascular plug in transcath-eter occlusion of PDAs in extremely premature infants. Catheter Cardiovasc Interv. 2017;89(6):1051–1058.

57. Sathanandam SK, Haddad LM, Subramanian S, et al. Unzipping of small diameter stents: an in vitro study. Catheter Cardiovasc Interv. 2015;85(2):249–258.

58. Sivakumar K, Bhagyavathy A, Coelho R, et al. Longevity of neonatal ductal stenting for congenital heart diseases with duct-dependent pulmonary circulation. Congenit Heart Dis. 2012; 7(6):526–533.

59. Tabatabaei H, Boutin C, Nykanen DG, et al. Morphologic and hemodynamic consequences after percutaneous balloon valvot-omy for neonatal pulmonary stenosis: medium-term follow-up. J Am Coll Cardiol. 1996;27(2):473–478.

60. Thapar MK, Rao PS. Significance of infundibular obstruction following balloon valvuloplasty for valvar pulmonic stenosis. Am Heart J. 1989;118(1):99–103.

61. Torres A, Vincent JA, Everett A, et al. Balloon valvuloplasty for congenital aortic stenosis: multi-center safety and efficacy outcome assessment. Catheter Cardiovasc Interv. 2015.

62. Warren M, Thompson KS, Popek EJ, et al. Pericardial effusion and cardiac tamponade in neonates: sudden unexpected death associated with total parenteral nutrition via central venous cath-eterization. Ann Clin Lab Sci. 2013;43(2):163–171.

63. Weber HS. Initial and late results after catheter intervention for neonatal critical pulmonary valve stenosis and atresia with intact ventricular septum: a technique in continual evolution. Catheter Cardiovasc Interv. 2002;56(3):394–399.

64. Weber HS. Catheter management of aortic valve stenosis in neonates and children. Catheter Cardiovasc Interv. 2006; 67(6):947–955.

65. West LJ. ABO-incompatible hearts for infant transplantation. Curr Opin Organ Transplant. 2011;16(5):548–554.

66. Zahn EM, Peck D, Phillips A, et al. Transcatheter closure of patent ductus arteriosus in extremely premature newborns: early results and midterm follow-up. JACC Cardiovasc Interv. 2016; 9(23):2429–2437.

67. Zellers TM, Dixon K, Moake L, et al. Bedside balloon atrial septostomy is safe, efficacious, and cost-effective compared with septostomy performed in the cardiac catheterization laboratory. Am J Cardiol. 2002;89(5):613–615.

68. Zuppan CW, Wells LM, Kerstetter JC, et al. Cause of death in pediatric and infant heart transplant recipients: review of a 20-year, single-institution cohort. J Heart Lung Transplant. 2009;28(6):579–584.

36. Marshall AC, Tworetzky W, Bergersen L, et al. Aortic valvulo-plasty in the fetus: technical characteristics of successful balloon dilation. J Pediatr. 2005;147(4):535–539.

37. McCrossan BA, McMahon CJ, Walsh KP. First reported use of drug-eluting bioabsorbable vascular scaffold in congenital heart disease. Catheter Cardiovasc Interv. 2016;87(2):324–328.

38. McElhinney DB, Lock JE, Keane JF, et al. Left heart growth, function, and reintervention after balloon aortic valvuloplasty for neonatal aortic stenosis. Circulation. 2005;111(4):451–458.

39. Mookhoek A, de Kerchove L, El Khoury G, et al. European mul-ticenter experience with valve-sparing reoperations after the Ross procedure. J Thorac Cardiovasc Surg. 2015;150(5):1132–1137.

40. Morray BH, McElhinney DB, Marshall AC, Porras D. Inten-tional fracture of maximally dilated balloon-expandable pulmo-nary artery stents using ultra-high-pressure balloon angioplasty: a preliminary analysis. Circ Cardiovasc Interv. 2016;9(4):e003281.

41. Mortell A, Said H, Doodnath R, et al. Transhepatic central venous catheter for long-term access in paediatric patients. J Pediatr Surg. 2008;43(2):344–347.

42. Muller MJ, Krause U, Paul T, Schneider HE. Serum levels after everolimus-stent implantation and paclitaxel-balloon angioplasty in an infant with recurrent pulmonary vein obstruction after repaired total anomalous pulmonary venous connection. Pediatr Cardiol. 2011;32(7):1036–1039.

43. Nakwan N, Choksuchat D, Saksawad R, et al. Successful treat-ment of persistent pulmonary hypertension of the newborn with bosentan. Acta Paediatr. 2009;98(10):1683–1685.

44. Noori S, Seri I. Neonatal blood pressure support: the use of inotropes, lusitropes, and other vasopressor agents. Clin Perina-tol. 2012;39(1):221–238.

45. Ootaki Y, Yamaguchi M, Yoshimura N, et al. The efficacy of pre-operative administration of a single dose of recombinant human erythropoietin in pediatric cardiac surgery. Heart Surg Forum. 2007;10(2):E115–E119.

46. Pedra CA, Pedra SR, Braga SL, et al. Short- and midterm follow-up results of valvuloplasty with balloon catheter for congenital aortic stenosis. Arq Bras Cardiol. 2003;81(2):120–128, 111–129.

47. Peng LF, Lock JE, Nugent AW, et al. Comparison of conven-tional and cutting balloon angioplasty for congenital and post-operative pulmonary vein stenosis in infants and young children. Catheter Cardiovasc Interv. 2010;75(7):1084–1090.

48. Peng LF, McElhinney DB, Nugent AW, et al. Endovascular stent-ing of obstructed right ventricle-to-pulmonary artery conduits: a 15-year experience. Circulation. 2006;113(22):2598–2605.

49. Perme T, Mali S, Vidmar I, et al. Prolonged prostaglandin E1 therapy in a neonate with pulmonary atresia and ventricular septal defect and the development of antral foveolar hyperplasia and hypertrophic pyloric stenosis. Ups J Med Sci. 2013;118(2):138–142.

50. Porras D, Brown DW, Rathod R, et al. Acute outcomes after introduction of a standardized clinical assessment and manage-ment plan (SCAMP) for balloon aortic valvuloplasty in con-genital aortic stenosis. Congenit Heart Dis. 2014;9(4):316–325.

51. Quartermain MD, Pasquali SK, Hill KD, et al. Variation in pre-natal diagnosis of congenital heart disease in infants. Pediatrics. 2015;136(2):e378–e385.

52. Rao PS. Transcatheter interventions in critically ill neonates and infants with aortic coarctation. Ann Pediatr Cardiol. 2009; 2(2):116–119.


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