Transcatheter Closure Of Sinus Venosus Atrial Septal Defect : An Innovative Technique

Dr Anil S.R Consultant Pediatric Cardiologist

Aster MedcityCochin

IntroductionSinus venosus atrial septal defect (SVASD) is located

high in the atrial septum where the right superior vena cava (RSVC) enters the right atrium, and is commonly associated with partial anomalous pulmonary venous connection (PAPVC) of right upper pulmonary vein (RUPV).

Transcatheter closure of such defects has not been described in the literature.

We have developed an innovative technique to close this defect by transcatheter means.

Introduction

Introduction

Case details

35 year old patient with SVASD and PAPVD of RUPV.

Presented with shortness of breathCVS: S1 normal, S2 wide split and fixed ESM, Grade 3/6 at upper left para-sternal area MDM at left lower para-sternal area

2 D EchoCHD, SDS, LevocardiaLarge SVC type of sinus venosus defect with L

to R shuntPAPVD of RUPV at RSVC-RA junctionDilated RA/RVBilateral SVC with LSVC draining to coronary

sinusNormal ventricular function

CT Scan

Hypothesis:In SVASD with PAPVD, posterior wall of RSVC

and anterior wall of RUPV are common but posterior wall of RUPV is normally connected to LA.

This formed the basis of our hypothesis that if we can separate the common wall of RSVC and RUPV by placing a covered stent in RSVC, RUPV should normally drain into LA and the defect will be closed.

Case descriptionCardiac catheterization was done under general

anaesthesia and transesophageal echocardiography (TEE) done in the same setting.

The site of drainage of RUPV into RSVC and lower end of sinus venosus ASD was profiled with an hand angiogram.

Balloon occlusion of SVC was done to study the relationship and flow pattern of RUPV

Case description

Hand injection done in RUPV while blocking the SVC with a balloon showed free flow of contrast into LA.

Simultaneous TEE showed that during the inflation of balloon in RSVC, there was unobstructed blood flow from RUPV to LA.

Hand injection in SVC. White arrow shows a catheter parked in RUPV delineating the abnormal drainage into SVC. IAS – inter atrial septum.

Hand injection done in RUPV while blocking the SVC with a balloon showed free flow of contrast into LA.

Confirmation of the Assumption

This confirmed our hypothesis that if we can create a common wall to separate SVC and RUPV with a covered stent, it will simultaneously close the defect and redirect RUPV flow into LA. In addition if the distal end of the stent is flared, it will close of the atrial communication

Measurements

Maximum RSVC diameter was measured as 9 mm.

Length of the stent was decided according to the distance between part of RSVC just inferior to azygous opening and portion of RA just beyond the lower end of ASD which was measured as 50 mm.

Selection of Stent

Based upon these measurements, 12mm x 61 mm balloon mounted adventa V12 covered stent was placed.

Stent Placement

Lower end of the stent was inflated for proper apposition with the atrial septum

Hand angiogram in RSVC showed free flow into RA, with no flow in LA

Angiogram done in RPA with pigtail catheter showed laminar flow of RUPV into LA

TEE showing good apposition of lower end of stent to the inter atrial septum (IAS) shown by arrow head. Colour Doppler showing trickle of blood flow (blue colour) across the IAS. LA – left atrium, RA – right atrium, SVC- superior vena cava

CT angiogram was done to confirm the above findings

Image A: Unobstructed RUPV flow (arrow) to left atrium (LA). Image B: Patent stent in SVC with lower end nicely opposed to inter atrial septum (IAS).

Follow-up

Post procedure, patient was put on dual anti-platelet therapy.

She is doing well on 6 months follow up and there is no evidence of stent migration, thrombosis or stenosis.

Conclusion

This is the first reported case of transcatheter closure of SV ASD.

The technique here describes the feasibility and the short term safety of the procedure in selected patients.