Changing patterns in the etiology of acute lower limb ischemia.

AIM: The aim of this study was to examine the causes of acute lower limb ischemia (ALLI) in a major referral center in Greece. METHODS: Hospital records of patients that were admitted with ALLI between January 1, 2000 and December 31, 2004, were retrospectively reviewed for this purpose. A total of 440 cases of ALLI in 351 patients were identified. RESULTS: In 174 (39.54%) cases, the ischemia was attributed to embolism; in 221 (50.23%) to thrombosis and in the remaining 45 (10.23%) to less common causes of ALLI (trauma [iatrogenic and non], vasculitis, dissection). Of 174 cases of embolism, 136 (78.16%) were of cardiac origin, 22 (12.64%) were due to non-cardiac emboli, while in the remaining 16 cases (9.2%) no specific origin of embolism was found. Of 221 cases of thrombosis 66 (29.86%) concerned native arterial thrombosis, while 155 (70.14%) concerned postinterventional thrombosis, including 144 (65.16%) cases of bypass graft thrombosis and 11 (4.98%) cases of iliac or femoral stent thrombosis. Sixty patients were admitted more than once with ALLI, most commonly due to repeated bypass graft thrombosis (85%). The latter was diagnosed in 32.73% of all ALLI cases and presented more often than native arterial thrombosis by a ratio of approximately 2.2:1. CONCLUSION: This study indicates that currently the leading cause for hospital admissions in patients with ALLI is thrombosis which most commonly occurs in bypass grafts rather than in native arteries.