State-of-the-Art Review: Alcohol Septal Ablation in Hypertrophic Cardiomyopathy

The objective of this review is to provide the reader with a synopsis of percutaneous alcohol septal ablation (ASA) as an effective and time-honored treatment modality in patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM).

Patients who have medically refractory symptoms of dynamic left ventricular outflow tract obstruction may benefit from septal reduction therapy including septal myectomy or ASA. ASA involves infusion of alcohol into an epicardial septal artery supplying the basal septum to generate an iatrogenic infarction and, thus, reduce outflow tract obstruction due to targeted hypocontractility early, septal thinning in the intermediate term, and remodeling late. Although ASA was historically reserved for higher risk surgical patients or for the elderly, recent data suggests that there may be no difference in functional status improvement and mortality when compared to the traditional surgical approach in carefully selected patients, and indeed some benefits of a less invasive strategy including less stroke. The most common complication of ASA remains complete atrioventricular block necessitating permanent pacemaker (PPM) placement, and reintervention rates of up to 10%, despite more experience and technical advances with the procedure.

ASA is an alternative to surgical myectomy (SM) with comparable functional status and mortality, with both procedures given a class I indication for symptomatic obstructive hypertrophic cardiomyopathy. Careful selection of patients and experienced operators in comprehensive HCM centers are imperative to the success of ASA.