Contemporary (2009-2014) clinical outcomes after femoropopliteal bypass surgery for chronic limb threatening ischemia are inferior to those reported in the UK Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL) trial (1999-2004)

Abstract

Background: Bypass surgery (BS) remains the gold standard revascularization strategy in patients with chronic limb-threatening ischemia (CLTI) owing to infrainguinal disease. The Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL)-1 trial showed that, in patients with CLTI who survived for 2 years or more, BS resulted in better clinical outcomes. Despite this finding, there has been an increasing trend toward an endovascular-first approach to infrainguinal CLTI. Our aim was to investigate whether changes in practice have impacted the clinical outcomes of BS in our unit 10 years after BASIL-1.

Methods: Data for patients who underwent femoropopliteal (FP) BS in BASIL-1 (1999-2004) were retrieved from trial case record forms. The comparator contemporary series (CS) comprised all patients undergoing FP BS for CLTI in our unit between 2009 and 2014. Demographic and clinical outcome data on patients in the CS were collected from the prospectively collected hospital electronic notes. Anatomic patterns of disease in the BASIL-1 and CS cohorts were scored using the Bollinger and GLASS criteria. Statistical analysis was performed in SAS v9.4.

Results: There were 128 patients from BASIL-1 and 50 patients in the CS. Baseline age, gender, affected limb, and diabetes prevalence were similar, as were days spent in hospital out to 12 months and length of follow-up. BASIL-1 patients were more likely to be current smokers (P = .000) and had a higher creatinine (P = .04). The 30-day morbidity and mortality were higher in BASIL-1 (45.3% vs 22%; P = .004). There was no significant difference between BASIL-1 and CS with regard to run-off Bollinger (37.7 vs 32.1; P = .167) and IP GLASS (0 vs 0; P = .390) scores, with both groups having a median of two runoff vessels. Amputation-free survival (62% vs 28%; hazard ratio [HR], 1.86; 95% confidence interval [CI], 1.18-2.93; P = .007), limb salvage (85% vs 69%; HR, 2.31; 95% CI, 1.14-4.68; P = .02), overall survival (69% vs 35%; HR, 1.66; 95% CI, 1.00-2.74; P = .05) and major adverse limb events (67% vs 47%; HR, 1.93; 95% CI, 1.15-3.22; P = .01) were all significantly better in BASIL-1.

Conclusions: Although 30-day mortality and morbidity were significantly lower, all of the examined longer term clinical outcomes after FP BS were significantly worse in the CS group a decade on from BASIL-1. Further research in the form of prospective cohort studies and randomized controlled trials is urgently required to determine if the CS data reported herein are generalizable to current vascular surgical practice and, if so, to determine the reasons for these unexpected outcomes.

Keywords: Chronic limb-threatening ischemia; Femoropopliteal bypass; Peripheral arterial disease.