Long-Term Follow-Up of Iliac Wallstents

Abstract

We evaluated the long-term results of the iliac artery stent placement for the treatment of patients with intermittent claudication. From November 1988 to December 1998, 303 legs were treated with metal stents in 259 patients with iliac occlusive arterial disease in a follow-up study approved by the institutional review board. Stenoses (n = 162) were treated after failed angioplasty and occlusions (n = 141) were treated with primary stent placement. According to Fontaine's clinical classification of chronic ischemia, 266 (88%) legs presented stage IIB, 14 (5%) stage III, and 23 (7%) stage IV. In all legs, self-expandable stents (Wallstent) were implanted. The patients were followed up with clinical examination, ankle brachial- index examination measurement and intravenous angiography. The data were analyzed using the univariate analysis (Kaplan-Meier method) and multivariate analysis (Cox proportional model). The primary endpoint of the study was the identification of restenosis or reoclusion of the stenting arterial segment and a secondary endpoint that was an identification of the risk factors of restenosis and reoclusion. The mean +/- SD ankle-brachial index pre-, post-procedure, and in the last control was 0.58 +/- 0.18, 0.90 +/- 0.23, and 0.86 +/- 0.24, respectively. Primary cumulative patency rates were 70% +/- 4 after 5 years, and 65% +/- 5 after 7 years, and secondary patency rates were 92% +/- 2 after 5 years, and 87% +/- 4 after 9 years. Immediate complications in the first 24 hours appeared in 12 (4%) legs, thrombosis in 5 legs, 3 legs presented with distal embolism, 2 thrombi at the access site and pseudo aneurysm and artery rupture in 1 leg. A patient died in the first 24 hours. Within 30 days after the procedure seven complications, 3 thromboses and 4 stenosis appeared. During follow-up, 42 (16%) patients died of other causes. The main causes of death were cardiac disease (39%), cerebrovascular disease (15%), cancer (7%), respiratory diseases (4%), and death due to accidents (2%), and other causes (9%). In 24% of the cases there was insufficient information to assign a principal cause of death. Thirty-six patients (13%) were lost to follow-up. Complications arose in 54 (18%) legs due to occlusion of the treated segment (29%), and stenosis due to intimal hyperplasia (27%). Thirteen patients required surgical treatment. Primary and secondary patency mean time was 80 +/- 3.7 and 102 +/- 2.4 months, respectively. We found no significant relation between patency and the quality of run-off, but a small vessel diameter and the female gender were negative predictive factors for failure (proportional hazards model). The use of stents for treatment of iliac artery occlusive disease may be considered an effective method with a low complication rate and acceptable long-term follow-up results.