Remote endarterectomy for arterial occlusive disease : Determinants for success

Abstract

The prevalence of peripheral arterial occlusive disease in the general population is 3-10%, and increases with age. The superficial femoral artery (SFA) is most commonly affected. A new technique to desobstruct the SFA is the minimal invasive remote superficial femoral artery endarterectomy (RSFAE). The aim of this thesis was to evaluate determinants for successful RSFAE and define its role in the spectrum of treatment options for SFA occlusive disease. Current treatment modalities for peripheral arterial disease were reviewed, with a focus on restorative interventions and drug therapy to suppress neointimal hyperplasia and prevent restenosis. The patency rates of RSFAE and supragenicular bypass surgery were compared in a multicentre randomised trial including 116 patients. Median hospital stay was significantly shorter following RSFAE: 4 versus 6 days (p = 0.004). Primary patency after 3-years follow-up was 47% for RSFAE and 60% for bypass (p = 0.107). Assisted primary and secondary patency were 63% versus 69% (p = 0.406), and 69% versus 73% (p = 0.541), respectively. Subdividing between venous and prosthetic grafts shows superior results for venous bypasses. Limb salvage was 97% after RSFAE and 95% after bypass (p = 0.564). It was concluded that RSFAE is a valuable alternative, with comparable assisted primary and secondary patency rates to bypass. In a study including 17 patients the desobstructed SFA was concomitantly treated with cryoplasty, to suppress neointimal hyperplasia. Primary patency at 1-year follow-up was 74%. In 8 patients the use of a stent at the distal transection zone could be ommited; cryoplasty was sufficient to secure the transection zone. The association between alcohol intake, cardiovascular events, and atherosclerotic plaque characteristics was investigated in 224 patients undergoing femoral and in 693 patients undergoing carotid endarterectomy. The Kaplan-Meier estimate of event rate in the femoral cohort after 3 years follow-up was 35% for no alcohol and 21% for 1-10 U/wk, whereas only 10% of >10 U/wk had sustained a major cardiovascular event (p = 0.010). In the carotid cohort the event rate did not differ. Plaques of the femoral population revealed larger lipid cores and more macrophage infiltration in patients abstaining from alcohol than in patients consuming alcohol, with a dose-response relationship. In the carotid population, no relationship was observed. In multivariate analysis alcohol consumption remained independently associated with a decreased risk for major cardiovascular events (HR 0.52 [95% CI 0.33-0.81]; p = 0.004). This study shows an inverse relationship between alcohol use and major cardiovascular events after endarterectomy for peripheral arterial occlusive disease, accompanied by a more stable plaque phenotype. 90 patients post-RSFAE were studied for the occurrence of restenosis. In 57 patients (63%) a restenotic lesion was diagnosed within 1 year. Patients with longer duration of ischemic walking complaints and small vessel size revealed a higher incidence of restenosis. In multivariate analysis, age (HR 1.61 [95% CI: 1.03-2.53]; p = 0.040), duration of ischemic walking complaints (HR 1.29 [95% CI: 1.03-1.62]; p = 0.030) and lumen diameter (HR 0.37 [95% CI: 0.19-0.72]; p <0.010) were independently associated with increased risk of restenosis.