Improved survival with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in chronic limb-threatening ischemia

Objective: Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) reduce the risk of cardiovascular events in patients with peripheral artery disease. However, their effect on limb-specific outcomes is unclear. The objective of this study was to assess the effect of ACE inhibitors/ARBs on limb salvage (LS) and survival in patients undergoing peripheral vascular intervention (PVI) for chronic limb-threatening ischemia (CLTI). Methods: The Vascular Quality Initiative registry was used to identify patients undergoing PVI for CLTI between April 1, 2010, and June 1, 2017. Patients with complete comorbidity, procedural, and follow-up limb and survival data were included. Propensity score matching was performed to control for baseline differences between the groups. LS, amputation-free survival (AFS), and overall survival (OS) were calculated in matched samples using Kaplan-Meier analysis. Results: A total of 12,433 limbs (11,331 patients) were included. The ACE inhibitors/ARBs group of patients had significantly higher prevalence of coronary artery disease (31% vs 27%; P < .001), diabetes (67% vs 57%; P < .001), and hypertension (94% vs 84%; P < .001) and lower incidence of end-stage renal disease (7% vs 12%; P < .001). Indication for intervention was tissue loss in 64% of the ACE inhibitors/ARBs group vs 66% in the no ACE inhibitors/ARBs group (P = .005). Postmatching survival analysis at 5 years showed improved OS (81.8% vs 79.9%; P = .01) and AFS (73% vs 71.5%; P = .04) with ACE inhibitors/ARBs but no difference in LS (ACE inhibitors/ARBs, 88.3%; no ACE inhibitors/ARBs, 88.1%; P = .56). After adjustment for multiple variables in a Cox regression model, ACE inhibitors/ARBs were associated with improved OS (hazard ratio, 0.89; 95% confidence interval, 0.80-0.99; P = .03) and AFS (hazard ratio, 0.92; 95% confidence interval, 0.84-0.99; P = .04). Conclusions: ACE inhibitors/ARBs are independently associated with improved survival and AFS in patients undergoing PVI for CLTI. LS rates remained unaffected. Further research is required to investigate the use of ACE inhibitors/ARBs in this population of patients, especially CLTI patients with other indications for therapy with ACE inhibitors/ARBs.