Circulatory Failure and Lactic Acidosis Associated with Giant Saphenous Vein Graft Aneurysm

Abstract

Context: Saphenous vein graft aneurysms may be a life-threatening condition. It may take 15-20 years to fully develop and is regarded as a relatively rare and late complication of coronary artery bypass grafting. Giant aneurysms may particularly cause mechanical complications due to neighboring structure compression. Simultaneous right atrial and ventricle compressions due to saphenous vein graft aneurysms as a cause of circulatory failure and lactic acidosis are rarely demonstrated in intensive care unit patients. Case report: We hereby report a case of a 74-year-old patient who was diagnosed with circulatory failure that developed into acute cardiac failure with obstructive shock. The patient had undergone coronary bypass grafting 20 years previously. Computed tomography angiography revealed a right-sided 6.7 × 7.1 cm paracardial aneurysm, originating from the venous graft, compressing the right atrium and ventricle inflow tract. Conclusions: We hypothesize that hemodynamic instability due to right ventricular inflow obstruction contributed to circulatory failure with consequently inadequate oxygen delivery and lactic acidosis. Despite immediate supportive treatment, the clinical condition deteriorated and a percutaneous intervention with a stent or surgical ligation with excision was not feasible thereafter. Saphenous vein graft aneurysms should be considered in patients with circulatory failure who have a history of coronary artery bypass grafting.