Angiotensin Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers (ACEI/ARB) are Associated with Improved Limb Salvage after Infrapopliteal Interventions for Critical Limb Ischemia.

BACKGROUND

Angiotensin-converting enzyme Inhibitors and Angiotensin II Receptor Blockers (ACEI/ARB) reduce the risk of cardiovascular events and mortality in patients with peripheral arterial disease (PAD). However, their effect on limb-specific outcomes is unclear. The objective of this study is to assess the effect of ACEI/ARB on patency and limb salvage in patients undergoing interventions for critical limb ischemia (CLI).

METHODS

Patients undergoing infrainguinal revascularization for CLI (Rutherford 4-6) between 06/2001 and 12/2014 were retrospectively identified. Primary Patency (PP), Secondary Patency (SP), Limb Salvage (LS), major adverse cardiac events (MACE), and survival rates were calculated using Kaplan-Meier. Multivariate analysis was performed using Cox regression.

RESULTS

A total of 755 limbs in 611 patients (311 ACEI/ARB, 300 No ACEI/ARB) were identified. Hypertension (86% vs. 70%, P < 0.001), diabetes (68% vs. 55%, P = 0.001) and statin use (61% vs. 45%, P < 0.001) were significantly greater in the ACEI/ARB group. Interventions were performed mostly for tissue loss (83% ACEI/ARB vs. 84% No ACEI/ARB, P = 0.73). Comparing ACEI/ARB versus No ACEI/ARB, in femoropopliteal interventions, 60-month PP (54% vs. 55%, P = 0.47), SP (76% vs. 75%, P = 0.83) and LS (84% vs. 87%, P = 0.36) were not significantly different. In infrapopliteal interventions, 60-month PP (45% vs. 46%, P = 0.66) and SP (62% vs. 75%, P = 0.96) were not significantly different. LS was significantly greater in ACEI/ARB (75%), as compared to No ACEI/ARB (61%) (P = 0.005). Cox regression identified diabetes (HR 2.4 (1.4-4.1), P = 0.002), ESRD (HR 3.5 (2.1-5.7), P < 0.001), hypertension (HR 0.4 (0.2-0.6), P < 0.001), and ACEI/ARB (HR 0.6 (0.4-0.9), P = 0.03), as factors independently associated with LS after infrapopliteal interventions. Freedom from MACE (ACEI/ARB 37% vs. 32%, P = 0.82) and overall survival (ACEI/ARB 42% vs. 35% No ACEI/ARB, P = 0.84) were not significantly different.

CONCLUSIONS

ACEI/ARB is associated with improved limb salvage in CLI patients undergoing infrapopliteal interventions, but not after femoropopliteal interventions. ACEI/ARB had no impact on patency rates. They were also associated with a trend toward improved survival and freedom from MACE. Our findings suggest that the use of ACEI/ARB may improve outcomes in the high-risk CLI patient population.