Frequency and Mechanism of Persistent Systolic Anterior Motion and Mitral Regurgitation After Septal Ablation in Obstructive Hypertrophic Cardiomyopathy

Relief of obstruction using ventricular septal ablation (VSA) may not eliminate systolic anterior motion (SAM) of the mitral valve and mitral regurgitation (MR) in patients with obstructive hypertrophic cardiomyopathy. The hypothesis was that persistent SAM after VSA was secondary to anterior papillary muscle displacement and malcoaptation of mitral valve leaflets and that these findings could predict persistence of SAM. Echocardiograms were examined from 37 patients with obstructive hypertrophic cardiomyopathy before and 12 ± 3 months after VSA. Anterior leaflet malposition (anterior-to-posterior leaflet coaptation position ratio), papillary muscle malposition (septal-to-lateral/left ventricular internal diameter ratio), and anterior position of coaptation relative to the septum (coaptation-to-septal distance) were assessed. MR proximal jet width was also measured. Of 37 patients, 30 underwent successful VSA (left ventricular outflow tract gradient reduction >50%); 22 of 30 and 7 of 7 with