Lee, C. van der

patient hypertrophic cardiomyopathy hypertrophic cardiomyopathy septal ptsma myectomy lvot gradient valve gradient coll cardiol study leaflet heart result follow-up echocardiography cardiol death circulation ethanol van der lee obstruction maron percutaneous transluminal septal outcome disease maron bj treatment therapy procedure echocardiographic population hypertrophy ablation volume reduction pregnancy lvot obstruction septal myectomy chapter mutation symptom surgery percutaneou mckenna wj prognosis cate fj outflow risk factors eur heart j tract j cardiol technique class leaflet extension outflow tract infarction systolic figure septum table york heart association contrast ethanol volume transluminal hemodynamic intracardiac echocardiography presence complication factor history hcm patients mckenna group hocm patients characteristic contrast echocardiography motion outflow tract obstruction