Pharmacotherapy in the treatment of mitral regurgitation: A systematic review

Background and aim of the study: Chronic mitral regurgitation (MR) causes volume overload on the left ventricle and, if uncorrected, will over time lead to left ventricular remodeling and heart failure. The benefits of angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) in primary MR are not well defined. Methods: MEDLINE was searched for studies in which the effects of ACE inhibitors and ARBs on chronic MR had been examined. The inclusion criteria required the patient population to have chronic MR, a normal left ventricular ejection fraction, and to report a quantitative measure of the change in MR severity. Studies in which patients had secondary MR were excluded. Results: Nineteen studies met the inclusion criteria (13 daily therapy, five single-dose, and one combined study). The pooled mean decrease in regurgitant fraction (RF) was 7.7% [95% CI 4.9, 10.6] and 9.3% [95% CI 3.4, 15.2] for studies in patients with daily therapy and single-dose therapy, respectively. Among studies which reported changes in regurgitant volume (RV), the pooled mean decrease was 7.9 ml [95% CI 1.4, 14.5]. For patients with mitral valve prolapse (MVP), the pooled mean reduction in RF was 8.1% [95% CI 4.3, 11.9] and in rheumatic disease it was 3.4% [95% CI 13.2 - 7.0]. Across the seven studies of daily therapy which reported a change in left ventricular end-diastolic volume index (LVEDVI), the mean decrease was 11.5 ml/m2 [95% CI 2.4, 20.6]. Conclusion: ACE inhibitors and ARBs each reduced the RF, RV, and left ventricular size by a modest degree in chronic primary MR.