Mega-Aneurysmal Degeneration of a Saphenous Vein Graft Following Infrainguinal Bypass

Abstract

True aneurysm formation in infrainguinal autologous vein grafts is rare. The authors report a case of a patient presenting with extensive aneurysmal degeneration of a femoropopliteal bypass vein graft 13 years after the original operation and 8 years after graft revision and thrombolysis for acute occlusion. Over a 2-year period, the vein graft aneurysm expanded from 2.7 to 4.5 cm maximal diameter. He underwent exclusion and partial resection of the vein graft aneurysm with placement of a new femoropopliteal bypass using reversed saphenous vein from the contralateral leg. Histopathologic examination of the aneurysm revealed intimal fibrosis, medial degeneration, and inflammation. This case and review of the literature suggests that true infrainguinal vein graft aneurysms occur infrequently and massive aneurysm degeneration is even more uncommon. Because of the rarity of true infrainguinal vein graft aneurysms, their etiology remains unclear.

Aneurisma de enxerto de veia safena após reconstrução arterial: relato de caso

“…Cassina et al 3 stated that vein graft aneurysms are caused by the progression of atherosclerosis, with subendothelial lipid deposits and foam cell formation, but other etiopathogenic factors and mechanisms could be involved. Corriere et al 2 emphasized the rarity of this clinical picture and report the association of inflammatory processes and media-intimal degeneration on the graft wall. Recently, Bikk et al…”

“…Aneurysms of saphenous vein grafts are rare occurrences 1,2,6,9 . The literature on the subject is comprised only of case reports, so data on its etiology and clinical evolution are inconsistent.…”

“…However, there are reports on such occurrence with aortorenal 7 , iliac-femoral 8 , carotid-carotid 9 , and infrainguinal bypass grafts 1,2 . Most patients are asymptomatic, and may present a pulsatile mass when the graft is in a superficial position.…”

“…Degeneration and aneurysm formation related to this graft are extremely rare 1 . The cause of venous graft degeneration remains unknown 1,2 , and some authors mistake it for atherosclerosis 3 or a process of blood vessel dilation 4 . Histopathological investigation has shown proliferative and fibrous lesions in the intima that lead to a significant weakening of the vein wall, favoring graft aneurysm formation 5 .…”

Aneurysmal Degeneration of Deep Lower Extremity Vein Conduits Used for Vascular Reconstruction

“…25,26 Cigarette smoking, hypercholesterolemia, and hypertriglyceridemia have been linked to aneurysm development. 26 However, some investigators have reported aneurysms in patients without any such risk factors.…”