Impact of Renin-Angiotensin System Blockade Therapy on Outcome in Aortic Stenosis

ObjectivesThe purpose of this study was to investigate the impact of renin-angiotensin system blockade therapy on outcomes in aortic stenosis (AS).BackgroundAngiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are perceived to be relatively contraindicated in AS. However, inhibitors of the renin-angiotensin system may be beneficial in AS through their cardioprotective and beneficial effects on left ventricular remodeling.MethodsThe Health Informatics dispensed prescribing, morbidity, and mortality database for the population of Tayside, Scotland, was linked through a unique patient identifier to the Tayside echocardiography database (>110,000 scans). Patients with a diagnosis of AS from 1993 to 2008 were identified. Cox regression model (adjusted for confounding variables) and propensity score analysis were used to assess the impact of ACEIs or ARBs on all-cause mortality and cardiovascular (CV) events (CV death or hospitalizations).ResultsA total of 2,117 patients with AS (mean age 73 ± 12 years, 46% men) were identified and 699 (33%) were on ACEI or ARB therapy. Over a mean follow-up of 4.2 years, there were 1,087 (51%) all-cause deaths and 1,018 (48%) CV events. Those treated with ACEIs or ARBs had a significantly lower all-cause mortality with an adjusted hazard ratio of 0.76 (95% confidence interval: 0.62 to 0.92, p < 0.0001) and fewer CV events with an adjusted hazard ratio of 0.77 (95% confidence interval: 0.65 to 0.92, p < 0.0001). The outcome benefits of ACEIs/ARBs were further supported by propensity score analysis.ConclusionsThis large observational study suggests that ACEI/ARB therapy is associated with an improved survival and a lower risk of CV events in patients with AS.