ACE Inhibitor Use in Aortic Regurgitation Associated with Reduced Mortality and CV Events
NEW ORLEANS, LA—The use of ACE inhibitors for patients with moderate to severe aortic regurgitation (AR) was associated with improved mortality and cardiovascular (CV) outcomes, according to the results of an observational cohort study reported upon at the American College of Cardiology 60th Annual Scientific Session.
AR is common and occurs in as many as 10% of middle-aged to older patients who undergo echocardiography. Approximately 6% of patients with AR progress to left ventricular (LV) systolic dysfunction, the latter which has a mortality rate of around 10%.
Study investigators led by Douglas Elder of the University of Dundee, UK, screened an echocardiographic database and identified patients with at least moderate AR. Using unique identifiers, patients were linked to demographic information, a dispensed prescribing database, primary care and secondary care data, laboratory results and registry office death data. Patients with moderate to severe AR (as reported by accredited sonographers) between 1993 and 2008 were identified. Individuals were excluded if they had any degree of aortic stenosis or if they had a malignancy diagnosed prior to the study's inclusion date. A Cox regression analysis was used to assess differences in all-cause mortality and CV events (CV death or hospitalizations) between those treated with and without ACE inhibitors, adjusted for confounding variables.
A total of 2,266 subjects with AR (aged 71.2 ± 14.2 years; 40% males) were studied with a mean follow-up of 4.4 ± 3.7 years. Of the total subjects, 876 (39%) received ACE inhibitor therapy. Those treated with ACE inhibitors had significantly lower all-cause mortality and fewer CV events, with an adjusted hazard ratio (HR) of 0.56 [0.64–0.89]; P=<0.01) for all-cause mortality and 0.77 [0.67–0.89], P=<0.01) for CV events. This translated into a 44% relative risk reduction in all-cause mortality and a 33% relative risk reduction in CV events. For a propensity score matched cohort analysis, the adjusted HR for CV events was 0.57 [0.41–0.79]; P=<0.01).
After mean follow-up, the research team recorded 582 (26%) deaths, 1,069 (47%) CV events, and 62 (2.7%) patients who underwent AVR during follow-up. Impact on the survival of ACE inhibitors/ARBs for patients with impaired LVSF yielded an HR of 0.56 [0.43 – 0.74] vs. 0.28 [CI 0.17 – 0.47] for patients with normal LVSF. The data also found that a diastolic diameter <6 cm was associated with an HR of 0.77 [0.67 – 0.90] vs. 0.52 [0.32–0.86] in diastolic diameters >6 cm.
“Prescription of ACE inhibitors and ARBs is associated with improved all-cause mortality and cardiovascular outcomes in patients with moderate to severe AR. Large prospective, randomized, controlled trials are needed to confirm these observational data,” Elder concluded during the presentation.