Syncope

INTRODUCTION: Spontaneous rupture of an aneurysmal bypass graft is very rare. The time of presentation varies from 2 months to 21 years after the surgery with chest pain as the most common symptom. To date this is the only reported case that presented with a syncopal episode.

CASE PRESENTATION: This is a case of a 68-year-old man who presented with syncope and cardiogenic shock. He had a 4 vessel coronary bypass 15 years ago. A two dimensional echocardiogram revealed a large extrinsic mass compressing the left atrium (Fig. 1). A chest computed tomogram (CT) confirmed the findings In addition the left pulmonary vein is also compromised (Fig. 2). Patient expired during resuscitation. An autopsy was performed and revealed a ruptured aneurysm of the bypass graft to the right coronary artery (Fig. 3) leading to hemopericardium with subsequent development of a localized tamponade compressing the left atrium and the left pulmonary vein.

[FIGURES 1-3 OMITTED]

DISCUSSIONS: In this case, the patient's presentation was very acute and his clinical status deteriorated rapidly. The initial working diagnosis was a metastatic mediastinal mass as he has a remote history colon cancer. The persistent compression to the left atrium and the left pulmonary vein ultimately led to the patient's death. The mechanism of the aneurysmal dilatation of bypass grafts is unclear and the actual incidence is unknown.

The mortality is high as most cases are undiagnosed. Diagnostic modality for early detection includes coronary angiography, computed tomography scan, cardiac magnetic resonance imaging and in some cases, transesophageal echocardiography. The treatment of choice is surgical resection with or with out the application of a new grafts. Trans-catheter embolization of the aneurysm has also been reported. With recent advances in coronary stents, implantation of polytetrafluoroethylene-covered stents (JOSTENTs) has been investigated.

CONCLUSION: Aneurysm of the saphenous venous graft is a very rare finding. Of particular interest was the difficulty in establishing the correct diagnosis due to its rarity. Furthermore, presentation can be atypical, and therefore the diagnosis should be considered in all patients who have had coronary surgery with saphenous vein grafts who present with atypical chest pain, superior vena caval obstruction, or mediastinal mass. In spite of limited data, early intervention of SVG aneurysm appears to be beneficial in most patient.

REFERENCES:

(1) Davey P, Gwilt D, Foffar C. Spontaneous rupture of a saphenous vein graft. Postgrad Med J. 1999 Jun;75(884):363-4.2.

(2) Toshihiro F, Shigefumi S, Toshihiko S. Aortocoronary saphenous vein graft aneurysm in redo coronary artery bypass grafting: Jpn j Surg (1998) 28:321-324.

(3) Kalimi R, Palazzo RS, Graver LM. Giant aneurysm of saphenous vein graft to coronary artery compressing the right atrium. Ann Thorac Surg. 1999 Oct;68(4):1433-7.

(4) Rogers JH, Chang D, Lasala JM. Percutaneous repair of coronary artery bypass graft-related pseudoaneurysms using covered JOS-TENTs. J Invasive Cardol. 2003 Sep;15(9):533-5.

DISCLOSURE: Jun Chiong, None.

Jun R. Chiong MD * Prithviraj Rai MD Carmel Montiero MD Sergey Malykh MD Alan B. Miller MD University of Florida, Jacksonville, FL

COPYRIGHT 2005 American College of Chest Physicians
COPYRIGHT 2005 Gale Group