Current status of nonsurgical septal reduction therapy in hypertrophic obstructive cardiomyopathy

Nonsurgical septal reduction therapy for hypertrophic obstructive cardiomyopathy patients has been available since 1994. Medium-term case series following alcohol septal ablation (ASA) are now available. Procedural risk is low and a significant improvement in symptom burden and left ventricular outflow tract gradient is observed in most cases. Success to medium-term is comparable to surgical septal myectomy. Increased risk of ventricular arrhythmia and sudden cardiac death has not been satisfactorily demonstrated post-ASA. Some series suggest improved survival following removal of the outflow tract gradient with ASA. Limited progress has been made in developing techniques in ASA since the introduction of myocardial contrast echocardiography. Refinements may be possible through improved guidance and imaging, but the need for alternative forms of nonsurgical septal reduction therapy is highlighted by technical and vascular limitations.