Early and Midterm Outcomes of Polytetrafluoroethylene-Covered Stent Versus Bare Metal Stent in the Primary Treatment of Severe Iliac Artery Obstructive Lesions

Abstract

through record review. Study end points were major adverse limb events (MALE), major amputations (AMPU), amputation-free survival (AFS) and mortality. Statistical analysis was performed using the Cox-proportional hazards model.Results: A total of 1906 lower extremity procedures were performed in 957 limbs with PAD; 622 patients (males, 363; females, 259) with a mean age 67.8 years, (range, 27-98). These included 713 open, 610 endovascular), and 75 hybrid revascularizations; and 192 primary and 340 secondary amputations. Half the procedures (52%) were performed for critical limb ischemia (CLI) and 7% were emergencies. The study population was predominantly white (96%); comorbidities included dyslipidemia in 62%, coronary artery disease in 47%, 26% with a prior intervention, current smoking in 42%, diabetes mellitus in 37%, and renal insufficiency (serum creatinine >2.0 mg/dL) in 8%. On univariate analysis the most significant risk factor associated with MALE and AMPU was presence of CLI (hazard ratio [HR], 3.1/7.1), followed by renal insufficiency on dialysis (HR, 3.2/5.2), emergency procedure (HR, 3.0/2.5), diabetes mellitus (HR, 2.0/3.9), and congestive heart failure (HR, 1.9/3.4). The prevalence of significant obesity (body mass index >35 kg/m 2 ) increased from 6% in the 5-year interval of 1990 to 1994 to 12% in 2005 to 2009, and was also significantly associated with MALE, AMPU, and AFS (HR, 2.4/4.3/ 1.5). In addition, factors associated with AFS and mortality included, age >75 years (HR, 2.4/2.8), anemia (HR, 2.7/2.8), and coronary artery disease without intervention (HR, 1.6/1.8). Table I summarizes multivariate analysis for factors significantly associated with all end points.Conclusions: This population-based study confirms the traditional risk factors for adverse outcomes following revascularization for PAD. Severe obesity is emerging as an important risk factor not previously reported especially in light of increasing incidence in the population.