Natural History and Management of Aortocoronary Saphenous Vein Graft Aneurysms

Abstract

Despite ongoing advances in percutaneous revascularization, coronary artery bypass grafting (CABG) continues to be performed in a large number of patients, with >400 000 operations reported in 2007 in the United States alone.1 Although arterial conduits are generally preferred, saphenous vein grafts (SVGs) continue to be used regularly. First described by Riahi and colleagues2 in 1975, aneurysmal dilatation of aortocoronary SVGs remains a rare yet widely reported phenomenon. Indeed, subsequent literature on the topic consists almost exclusively of case reports and small case series. Thus, the precise incidence of aortocoronary SVG aneurysms (SVGAs) remains difficult to ascertain, although in 1 case series, an incidence of 0.07% was estimated from a review of >5500 grafts at a single institution.3 However, this likely underestimates the true number because SVGAs often remain clinically silent and no guidelines exist to screen for their development. Given the infrequent identification of SVGAs, our current understanding of the epidemiology and pathogenesis of these aneurysms remains limited. Aneurysms are generally defined as a focal dilatation of vessels >1.5 times the proximal reference diameter; however, aneurysmal dilatation of aortocoronary SVGs has led to “giant” aneurysm formation, with reports of cases exceeding 10 cm.4–6 SVGAs are often incidentally identified on imaging, but cases of rupture,7 fistula formation with neighboring anatomy,8 and hemodynamic compromise resulting from compression of adjacent cardiac and vascular structures have been reported.9 To date, 2 reviews have been published that briefly summarize 108 cases of SVGAs.10,11 Traditionally, their management has been surgical—generally resection of the aneurysm with or without bypass of the affected territory. However, with refinement of percutaneous techniques, including the use of Amplatzer devices, covered stents, and arterial coiling, the management options …