Surgical septal myectomy for hypertrophic cardiomyopathy. The Iranian experience.

Introduction: Hypertrophic obstructive cardiomyopathy (HOCM) is a hereditary heart muscle disorder characterized by significant myocardial hypertrophy. we assessed perioperative and long-term follow-up data of Iranian HOCM patients who underwent SM in 2 pioneering centers.

Methods: Clinical data of patients with HOCM septal myectomy are collected. Thirty-day outcome and long-term follow-up data for recurrence of gradient and mortality are reported.

Results: Ninety-six patients in two different centers enrolled in the study. Most patients of 52 patients in center 1 were male (34/52 [65.3%]).and the mean age was of 36.7  ±  19 years. Syncope before admission was reported in 5.7%, the mean left ventricular ejection fraction on admission was 53  ±  8%, the mean left ventricular outflow tract gradient was 66.3  ±  20.4 mm Hg, and the mean preoperativeseptal thickness was 25.4  ±  6.7 mm. A redo SM was performed in 3 patients (5.8%), mitral valve repair in 5 patients (9.6%), and atrioventricular repair in 5 patients (9.6%). A residual systolic anterior motion was detected in 4 patients (7.7%), the mean postoperative septal thickness was 19  ±  6 mm (25.1% septal thickness reduction), and in-hospital mortality was 5.8% (n  =  3). A longer-term follow-up showed death in 3 patients (5.8%) and late recurrent left ventricular outflow tract obstruction in 1 patient.

Conclusions: Transaortic myectomy is an effective surgery with acceptable early and late mortality rates. Improvements in functional status are seen in almost all patients. Appropriate SM is crucial to a good clinical outcome. Long-term survival is excellent and cardiac sudden death is extremely rare after a good surgical treatment.