Routine Papillary Muscle Realignment and Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: Septal myectomy has been the mainstay of the surgical treatment of obstructive hypertrophic cardiomyopathy (HCM); however, recently there is growing appreciation for associated mitral valve abnormalities that contribute to left ventricular outflow tract (LVOT) obstruction. In this study, we describe our experience with combined papillary muscle realignment (PMR) and septal myectomy for the treatment of obstructive HCM.

METHODS: We identified 44 patients undergoing surgery for obstructive HCM whose anatomy was amenable to combined PMR and septal myectomy at our institution over a 20-month period. All patients underwent resting and stress echocardiography preoperatively and postoperatively. Demographic, clinical, and imaging data were prospectively collected in a cardiac surgery database.

RESULTS: Patient age ranged broadly, with mean age of 54 (range, 18 to 76) years. Preoperatively, 70% of patients were New York Heart Association functional class III or IV, the mean stress LVOT gradient was 144 mm Hg, and severe mitral regurgitation (MR) with stress was seen in 81%. Additional procedures included division of myocardial bands (50%) and chordae (43%) and resection of accessory papillary muscles (25%). Following the procedure, mean resting and stress gradients were reduced to normal (12 and 27 mm Hg, respectively; p < 0.0001). No patient had severe MR and only 3 (6.8%) had moderate MR (p < 0.0001). Mean length of stay was 6 days and there were no mortalities.

CONCLUSIONS: Septal myectomy combined with PMR is a safe, highly effective, and reproducible procedure that reliably relieves LVOT obstruction and corrects MR without the need for mitral valve repair or replacement.