Lower extremity bypass for critical limb ischemia decreases major adverse limb events with equivalent cardiac risk compared with endovascular intervention

Abstract

Objective: Lower extremity bypass (LEB) has traditionally been the "gold standard" in the treatment of critical limb ischemia (CLI). Infrainguinal endovascular intervention (IEI) has become more commonly performed than LEB, but comparative outcomes are limited. We sought to compare rates of major adverse limb events (MALEs) and major adverse cardiovascular events (MACEs) after LEB and IEI in a propensity score-matched, national cohort of patients with CLI.

Methods: The National Surgical Quality Improvement Program (NSQIP) vascular targeted files (2011-2014) for LEB and IEI were merged. CLI patients were identified by ischemic rest pain or tissue loss. Patients were matched on a 1:1 basis for propensity to undergo LEB or IEI. Primary outcomes were 30-day MALEs and MACEs. Within the propensity-matched cohort, multivariate logistic regression was used to identify independent predictors of MALEs and MACEs.

Results: A total of 13,294 LEBs and IEIs were identified, with 8066 cases performed for CLI. Propensity matching identified 3848 cases (1924 per group). There were no differences in preoperative variables between the propensity-matched LEB and IEI groups (all P > .05). At 30 days, rates of MALEs were significantly lower in the LEB group (9.2% LEB vs IEI 12.2%; P = .003). On multivariate logistic regression, bypass with single-segment saphenous vein vs IEI (odds ratio [OR], 0.7; 95% confidence interval [CI], 0.54-0.92; P = .01), bypass with alternative conduit (prosthetic, spliced vein, or composite) vs IEI (OR, 0.7; 95% CI, 0.56-0.98; P = .04), antiplatelet therapy (OR, 0.8; 95% CI, 0.58-1.00; P = .049), and statin therapy (OR, 0.8; 95% CI, 0.62-0.99; P = .04) were protective against MALEs, whereas infrageniculate intervention (OR, 1.4; 95% CI, 1.09-1.72; P = .01) and a history of prior bypass of the same arterial segment (OR, 1.8; 95% CI, 1.41-2.41; P <. 0001) were predictive. Rates of 30-day MACEs were not significantly different (4.9% LEB vs 3.7% IEI; P = .07) between the groups. Independent predictors of MACEs included age (OR, 1.02; 95% CI, 1.01-1.04; P = .01), steroid use (OR, 1.8; 95% CI, 1.08-2.99; P = .03), congestive heart failure (OR, 1.7; 95% CI, 1.00-1.96; P = .02), beta blocker use (OR, 1.6; 95% CI, 1.09-1.43; P = .01), dialysis (OR, 2.3; 95% CI, 1.55-3.45; P < .0001), totally dependent functional status (OR, 3.1; 95% CI, 1.25-7.58; P = .02), and suboptimal conduit for LEB compared with IEI (OR, 1.6; 95% CI, 1.08-2.36; P = .02).

Conclusions: Within this large, propensity-matched, national cohort, LEB predicted lower risk-adjusted 30-day MALE rate compared with IEI. Furthermore, there was no difference in 30-day MACE rate between the groups despite higher inherent risk with open surgical procedures. Therefore, this study supports the effectiveness and primacy of LEB for revascularization in CLI.