Determinants of survival and major amputation after peripheral endovascular intervention for critical limb ischemia

Abstract

Objective: Our objective was to analyze periprocedural and 1-year outcomes of peripheral endovascular intervention (PVI) for critical limb ischemia (CLI).

Methods: We reviewed 1244 patients undergoing 1414 PVIs for CLI (rest pain, 29%; tissue loss, 71%) within the Vascular Study Group of New England (VSGNE) from January 2010 to December 2011. Overall survival (OS), amputation-free survival (AFS), and freedom from major amputation at 1 year were analyzed using the Kaplan-Meier method. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: The number of arteries treated during each procedure were 1 (49%), 2 (35%), 3 (12%), and ≥4 (5%). Target arterial segments and TransAtlantic Inter-Society Consensus classifications were aortoiliac, 27% (A, 48%; B, 28%; C, 12%; and D, 12%); femoral-popliteal, 48% (A, 29%; B, 34%; C, 20%; and D, 17%); and infrapopliteal, 25% (A, 17%; B, 14%; C, 25%; D, 44%). Technical success was 92%. Complications included access site hematoma (5.0%), occlusion (0.3%), and distal embolization (2.4%). Mortality and major amputation rates were 2.8% and 2.2% at 30 days, respectively. Overall percutaneous or open reintervention rate was 8.0% during the first year. At 1-year, OS, AFS, and freedom from major amputation were 87%, 87%, and 94% for patients with rest pain and 80%, 71%, and 81% for patients with tissue loss. Independent predictors of reduced 1-year OS (C index = .74) included dialysis (HR, 3.8; 95% CI, 2.8-5.1; P < .01), emergency procedure (HR, 2.5; 95% CI, 1.0-6.2; P = .05), age >80 years (HR, 2.2; 95% CI, 1.7-2.8; P < .01), not living at home preoperatively (HR, 2.0; 95% CI, 1.4-2.8; P < .01), creatinine >1.8 mg/dL (HR, 1.9; 95% CI, 1.3-2.8; P < .01), congestive heart failure (HR, 1.7; 95% CI, 1.3-2.2; P < .01), and chronic β-blocker use (HR, 1.4; 95% CI, 1.0-1.9; P = .03), whereas independent preoperative ambulation (HR, 0.7; 95% CI, 0.6-0.9; P = .014) was protective. Independent predictors of major amputation (C index = .69) at 1 year included dialysis (HR, 2.7; 95% CI, 1.6-4.5; P < .01), tissue loss (HR, 2.0; 95% CI, 1.1-3.7; P = .02), prior major contralateral amputation (HR, 2.0; 95% CI, 1.1-3.5; P = .02), non-Caucasian race (HR, 1.7; 95% CI, 1.0-2.9; P = .045), and male gender (HR, 1.6; 95% CI, 1.1-2.6; P = .03), whereas smoking (HR, .60; 95% CI, 0.4-1.0; P = .042) was protective.

Conclusions: Survival and major amputation after PVI for CLI are associated with different patient characteristics. Dialysis dependence is a common predictor that portends especially poor outcomes. These data may facilitate efforts to improve patient selection and, after further validation, enable risk-adjusted outcome reporting for CLI patients undergoing PVI.

Fig 1

Kaplan-Meier curve of overall survival (OS) after peripheral vascular intervention (PVI) for critical limb ischemia (CLI). EST, Estimated survival; SE, standard error.

Fig 2

Kaplan-Meier curve of amputation-free survival (AFS) after peripheral vascular intervention (PVI) for critical limb ischemia (CLI). EST, Estimated survival; SE, standard error.

Fig 3

Kaplan-Meier curve of major amputation after peripheral vascular intervention (PVI) for critical limb ischemia (CLI). EST, Estimated survival; SE, standard error.