Surgical septal myectomy versus alcohol septal ablation: assessing the status of the controversy in 2014.

1617 I n hypertrophic cardiomyopathy (HCM), left ventricular (LV) outflow tract obstruction, caused by mitral valve sys-tolic anterior motion (SAM) with elevated intracavitary LV pressures, can produce disabling symptoms of heart failure and excess cardiovascular mortality. Outflow gradients are common in HCM, present in 70% of patients at rest or with physiological exercise 4 (Figure 1). Fifty years ago, early HCM investigators recognized the importance of obliterating LV out-flow obstruction (and mitral regurgitation) and restoring normal hemodynamics, initially with the septal myectomy operation advanced by Dr Andrew Morrow at the National Institutes of Health. 6,7 However, HCM has not been immune to controversy, and through the years, several debates have focused on the significance of dynamic outflow obstruction and its treatment. 7 The most recent of these conversations concerns the most effective strategy for reducing gradient and symptoms, triggered by the introduction of catheter-based percutaneous alcohol septal ablation (ASA) as an alternative to myectomy. 8 involves injection of 1 to 4 mL of 96% ethanol into the first septal per-forator branch of the left anterior descending coronary artery to produce a basal septal myocardial infarction and ultimately remodeling of the LV outflow tract. ASA avoids the recovery time with loss of work, residual discomfort, and anxiety associated with surgery. It was soon enthusiastically embraced and heavily promoted by many clinicians and interventional cardi-ologists, initially in Europe, thereby expanding the treatment armamentarium of HCM and triggering a polarized and sometimes contentious debate within the cardiovascular community. Indeed, many related issues remain incompletely resolved despite >450 published articles, including 250 since this controversy first appeared in the pages of Circulation almost 8 years ago (2007). 20 The purpose of revisiting this topic here is to update this major clinical issue in cardiovascular medicine , introducing a measure of clarity and balance and taking into consideration all assembled data, literature, expert opinion and perspectives, consensus documents, and American College of Cardiology (ACC)/American Heart Association (AHA) guidelines. Over time, the fundamental questions involved with surgery versus ablation may have become oversimplified or obscured. For example, is the key issue whether the newer technique (ie, ASA) is, in fact, better than the older, established, and time-honored myectomy operation? What does " better " really mean? Should ASA become the primary treatment strategy, with surgery relegated to a backup role when ASA fails, as some interventionalists have suggested? Has the myectomy operation become obsolete in an …