cihtddtts

Acc

ttmowrg(tircharDtoCt

ttwcnaLdretipt

aposasmao

Asymptomatic Giant TraumaticRight Coronary ArteryPseudoaneurysm Caused by SternalFractureDaisuke Yoshioka, MD, Hironori Izutani, MD, PhD,Masahiro Ryugo, MD, PhD, Kanji Kawachi, MD, PhD,and Yoshiki Sawa, MD, PhD

Cardiovascular and Thoracic Surgery, Ehime UniversityGraduate School of Medicine, To-on City, Ehime andDepartment of Cardiovascular Surgery, Osaka UniversityGraduate School of Medicine, Suita City, Osaka, Japan

Giant traumatic coronary artery pseudoaneurysm is ex-tremely rare, and very few cases of traumatic coronaryartery aneurysm have been previously reported. Wepresent a case of an asymptomatic, giant, traumatic rightcoronary artery pseudoaneurysm caused by blunt chesttrauma and sternal fracture. The risk of rupture orperipheral embolization remains unclear, but we believethat pseudoaneurysm resection and coronary artery by-pass grafting are adequate procedures for preventingrupture or ischemia.

(Ann Thorac Surg 2011;92:e33–5)© 2011 by The Society of Thoracic Surgeons

Coronary artery aneurysm is rare in adult patients,and atherosclerosis is the most common cause of

oronary artery aneurysm followed by inflammation,nfections, and connective tissue disorders. On the otherand, coronary pseudoaneurysm is much less common

han true aneurysm, and is mostly caused by arterialissection or rupture after catheter intervention. Pseu-oaneurysms caused by blunt chest trauma are ex-

remely rare. We describe a case of asymptomatic giantraumatic coronary artery pseudoaneurysm caused byternal fracture.

69-year-old man without significant risk factors fororonary artery disease was referred to our hospital for aoronary aneurysm. He had no remarkable medical his-

Accepted for publication March 8, 2011.

Address correspondence to Dr Yoshioka, Sitsukawa, To-on city, Ehime791-0295, Japan; e-mail: djason55@gmail.com.

© 2011 by The Society of Thoracic SurgeonsPublished by Elsevier Inc

ory, with no record of Kawasaki disease or other infec-ious or inflammatory diseases. Prior annual routine

edical examinations never showed any abnormalitiesn the patient’s chest roentgenogram before. In addition,hen he underwent cholecystectomy 5 years ago, no

emarkable abnormality was detected by electrocardio-ram, chest roentgenogram, or computed tomographicCT) scan. However, 4 years ago, he received conserva-ive treatment for a sternal fracture caused by a chestnjury after falling from a ladder. When he underwent aoutine medical examination 1 year after the accident, ahest roentgenogram showed a large mass in his righteart segment, which was not detected at the time of theccident. An additional chest CT scan showed a giantight coronary artery (RCA) aneurysm (diameter, 7 cm).uring a 3-year follow-up since the aneurysm was iden-

ified, a repeated plain CT scan showed no enlargementf the aneurysm. However, the latest contrast-enhancedT showed an enhancement of the aneurysm cavity, and

he risk of aneurysm rupture was suspected (Fig 1).Coronary angiography demonstrated total occlusion of

he proximal RCA and small collateral arteries enteringhe aneurysm cavity (Fig 2). The distal branch of the RCAas perfused with collateral arteries from the normal left

oronary artery. Echocardiography showed an almostormal left ventricular function and normal function ofll valves, except hypokinetic motion of the inferior wall.aboratory findings showed no risk factors, such asiabetes mellitus or hypercholesterolemia for arterioscle-osis. Although the patient had no angina pectoris ornlarged aneurysm for 3 years, surgical risks, as well ashe potential risks of aneurysm rupture and thromboticnfarction of RCA were discussed in detail with theatient. Surgical intervention was planned on the basis of

he patient’s desire.Elective coronary artery bypass grafting to the RCA

nd resection of the coronary artery aneurysm wereerformed. After a median sternotomy and pericardiot-my, a giant mass (7 cm in diameter) was clearly ob-erved in the right atrium and ventricle (Fig 3). When theneurysm was retracted, the intact right atrial wall wasufficient for venous cannulation. Therefore, cardiopul-onary bypass was initiated along with cannulation of the

scending aorta and right atrium. The aneurysm waspened longitudinally, and a large organized thrombus was

Fig 1. (A) The three-dimensional computedtomographic (CT) scan showed the large rightcoronary artery aneurysm in a diameter of 7cm (*). (B) The contrast-enhanced CT scanshowed enhancement of the aneurysmal cavity(arrows).

0003-4975/$36.00doi:10.1016/j.athoracsur.2011.03.046

e34 CASE REPORT YOSHIOKA ET AL Ann Thorac SurgGIANT TRAUMATIC CORONARY PSEUDOANEURYSM 2011;92:e33–5

evacuated. After removing the thrombus, active bleedingfrom the orifice of the proximal coronary artery was iden-tified and closed with sutures. The distal orifice of the RCAwas not identified. Several small vessels entering theaneurysm were electrically cauterized. After coronaryartery bypass to the distal side of the RCA from theascending aorta using a saphenous vein graft (SVG),the aneurysm wall was resected as much as possible, andthe residual sac was obliterated with running sutures.The patient was weaned from cardiopulmonary bypasswithout difficulty, and he made an uneventful recovery.After surgery, a CT chest scan showed the patent’s SVGgraft had no residual enhancement of the sac, andechocardiography showed improvement in the motion ofthe inferior wall.

Fig 2. The coronary angiography demonstrated total occlusion of theproximal right coronary artery and small collateral arteries enteringthe aneurysmal cavity (arrows).

Fig 3. A giant mass (sized, 7 cm in diameter) was on the right

atrium and the right ventricle (*).

The pathologic finding of the resected aneurysm wallwas a loss of vessel wall integrity with organized intra-mural thrombus formation. Invasion of lymphocytes andplasmacytes was detected in the primary adventitia of thecoronary artery. Fibrotic tissue (and not an internalelastic lamina or smooth muscle) was observed in theaneurysm wall. The pathology was compatible with thatof a coronary pseudoaneurysm (Fig 4).

Comment

The most common cause of a giant coronary arteryaneurysm is atherosclerosis. Other reported causes arecongenital malformations, such as those accompaniedwith coronary artery fistula, inflammatory disease (arteri-tis and Kawasaki disease), iatrogenic causes (after coro-nary angiography), connective tissue diseases (Marfan’ssyndrome or Ehlers–Danlos syndrome), and infectiousconditions [1]. In another case, Takeda and colleagues [2]reported a giant coronary artery aneurysm associatedwith cystic medial necrosis in a non-Marfan patient.

Coronary artery pseudoaneurysms are substantiallyless common than “true” aneurysms. They usually occurafter catheter-based coronary interventions as a result oftraumatic dissection or perforation of the coronary artery,which leads to disruption of the media without bloodleakage through the adventitia, or as a result of deepresection of the vessel wall in directional atherectomy.Coronary artery pseudoaneurysms can occur spontane-ously, due to trauma, and in association with cardiactumors. Spontaneous coronary pseudoaneurysms haverarely been described and can have variable presentingsymptoms. Most spontaneous coronary artery pseudoa-neurysms develop with angina pectoris or myocardialinfarction [3, 4]. Furthermore, asymptomatic coronaryartery pseudoaneurysms after blunt chest trauma arerare. Only 1 patient sustained blunt chest trauma due toan automobile accident and underwent surgical pseudo-

Fig 4. Elastica van Gieson stain (�12.5) of the resected aneurysmwall was shown to be ruptured external elastic lamina and prolifer-ated fibrotic tissue, and an internal elastic lamina or smooth musclewas not observed in the aneurysm wall.

aneurysmectomy 12 years later [5]. In our case, the

e35Ann Thorac Surg CASE REPORT YOSHIOKA ET AL2011;92:e33–5 GIANT TRAUMATIC CORONARY PSEUDOANEURYSM

pseudoaneurysm was not identified at the time of theaccident, but a sternal fracture was suspected to havecaused RCA injury, resulting in pseudoaneurysm forma-tion 1 year later.

The prognosis of an atherosclerotic coronary aneurysmis usually favorable. However, Aqel and colleagues [4]reported that the prognosis of a pseudoaneurysm devel-oping after percutaneous intervention, as a result ofperforation of the vessel wall is associated with anadverse outcome, if untreated. The risk is due to throm-bosis with distal embolization or rapid enlargement andrupture leading to cardiac tamponade. However, the riskof spontaneous coronary artery pseudoaneurysms re-mains unknown because of the low incidence of thedisease. Treatment should be considered for coronaryrevascularization and management of the coronary arterypseudoaneurysm on a case-by-case basis.

In our case, the coronary artery pseudoaneurysm didnot enlarge for 3 years, and the patient had no anginapectoris. However, an echocardiogram showed hypoki-netic motion of the inferior wall, and silent myocardial

ischemia was suspected. In addition, enhancement of the

aneurysm cavity on contrast-enhanced CT scan and thesmall arteries running into the aneurysm on coronaryangiogram implied the risk of aneurysm rupture. Webelieve that pseudoaneurysm resection and coronaryartery bypass grafting are adequate procedures for pre-venting rupture or ischemia.

References

1. Robinson S. Aneurysms of the coronary arteries. Am Heart J1985;109:129-3c5.

2. Takeda K, Matsumiya G, Nishimura M, Matsue H, Tomita Y,Sawa Y. Giant circumflex coronary artery aneurysm associ-ated with cystic medial necrosis in a non-Marfan patient. AnnThorac Surg 2007;83:668–70.

3. Izutani H, Shibukawa T, Kawamoto J, Ishibashi K. Spontane-ous right coronary artery pseudoaneurysm. Gen Thorac Car-diovasc Surg 2007;55:259–61.

4. Aqel RA, Zoghbi GJ, Iskandrian A. Spontaneous coronaryartery dissection, aneurysms, and pseudoaneurysms: a re-view. Echocardiography 2004;2:175–82.

5. Iemura J, Oku H, Shirotani H. Right coronary artery pseu-doaneurysm after blunt injury to the chest. Heart 1996;

76:86.