Abstract 16222: The Effect of Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy on Mitral Regurgitation
Introduction: Hypertrophic Obstructive Cardiomyopathy (HOCM) is associated with systolic anterior motion of the mitral valve, frequently leading to mitral regurgitation (MR). We hypothesized that after septal reduction with alcohol septal ablation (ASA), left ventricular outflow tract gradients would be reduced and mitral regurgitation would improve.
Methods: We reviewed echocardiograms at baseline and 3 month post ASA for 210 consecutive patients treated at the Medical University of South Carolina between 2000 and 2007 for whom complete echo data was available. For each echocardiogram the left atrial end-systolic volume index (LAESVI), resting left ventricular outflow tract (LVOT) gradient, degree of mitral regurgitation and mitral regurgitation jet area were assessed.
Results: Mitral regurgitation was seen in 70% of patients at baseline (Figure 1A). ASA significantly reduced regurgitation, with only 41% having mild or greater MR at three months (70% vs 41%, p=<0.001), and nearly eliminated more severe MR with only 6% remaining moderate or greater (29% vs 6%, p=<0.001). Baseline resting LVOT gradient correlated with mitral regurgitation severity (1B) and was significantly reduced at follow-up (70mmHg vs 30.7mmHg, p=<0.001). Reduction in MR was further supported by a significant reduction in MR jet area (1C) and translated into reduced LAESVI, seen across all degrees of regurgitation (1D, p=<0.05 for each category).
Conclusions: Mitral regurgitation is present in a high percentage of patients referred for ASA. In addition to reducing LVOT gradient, ASA significantly reduces degree of MR with resulting improvement in left atrial size.
- © 2011 by American Heart Association, Inc.