Abstract 11049: Left Ventricular Systolic Function is Preserved Following Alcohol Septal Ablation for Symptomatic Hypertrophic Obstructive Cardiomyopathy: The University of Colorado and Denver VAMC Experience 2002 to 2011
INTRODUCTION: Hypertrophic obstructive cardiomyopathy (HOCM) is a heritable condition that portends an adverse prognosis via left ventricular outflow tract (LVOT) obstruction and ventricular dysfunction and sudden death. Alcohol septal ablation (ASA) is an alternative to surgical septal myectomy for treatment of symptomatic HOCM. Because ASA results in a myocardial infarct of up to 10% of ventricular mass, concerns have been raised that left ventricular systolic function could decline over time. We evaluated left ventricular function during longitudinal follow-up in a cohort of patients who underwent ASA.
METHODS: We studied 146 consecutive patients with HOCM that underwent 168 ASA procedures from 2002 to 2011. Follow-up was available in 94.5% (n= 138) of patients. Echocardiographic indices included left ventricular ejection fraction (LVEF), mitral regurgitation (MR) severity, systolic anterior motion of the mitral leaflet or systolic anterior motion (SAM), and resting and provoked LVOT gradients. Other observations included New York Heart Association [NYHA] class, AV block, repeat ASA, and death.
RESULTS: All patients had a normal baseline left ventricular ejection fraction (> 55%). Septal infarct was achieved with injection of ethanol (mean volume: 4.2 ± 1.7 ml) into 1.2 ± 0.4 septal perforator arteries. Over a mean follow-up time of 3.1 ± 2.8 years (range: 7 days to 9.6 years) LVEF was preserved in 97.3% of patients. Of the four patients who developed LV dysfunction, only mild LV dysfunction was observed (LVEF 45-50%) in each. Repeat ASA was performed in 14% (n= 21). MR severity improved in 67% (n= 86 of 129 with complete data). SAM improved in 39% (n= 49 of 126). LVOT gradients remained low throughout the follow-up period; resting gradient declined from a mean of 75 to 30 mm Hg (p<0.001), and provoked gradient declined from a mean of 101 to 45 mm Hg (p < 0.001). NYHA class improved from a mean of 2.9 ± 0.4 to 1.3 ± 0.5 (p < 0.001). There were 14 deaths (9.6%) of which 3 were adjudicated to be sudden deaths (2.2%).
CONCLUSIONS: Left ventricular systolic function is preserved following ASA for symptomatic HCM; while other echocardiographic and functional measures are significantly improved.
- © 2013 by American Heart Association, Inc.