Septal myectomy with subvalvular apparatus intervention in patients with hypertrophic obstructive cardiomyopathy: immediate results

Aim. Surgical septal myectomy is a standard treatment option for patients with hypertrophic obstructive cardiomyopathy. Subvalvular abnormalities of the mitral valve may play an important role in residual left ventricular outflow tract obstruction. This study aimed to evaluate the surgical outcomes of septal myectomy with subvalvular interventions.Material and Methods. Between July, 2015 and December, 2016, 40 eligible patients underwent septal myectomy with subvalvular intervention. The peak gradient was 92.3±16.9 mm Hg. The mean septum thickness was 26.8±4.5 mm. Moderate or severe systolic anterior motion syndrome-mediated mitral regurgitation was observed in all patients.Results. There was no residual mitral regurgitation. Residual systolic anterior motion syndrome was observed in 5%. The postoperative gradient was 8.7±4.5 mm Hg. At 12-month follow-up, all patients were alive. According to the New York Heart Association (NYHA) classification, 87.5 and 12.5% of patients had NYHA functional classes I and II, respectively. The prevalence rate of residual mitral regurgitation was 10%.Conclusions. Concomitant subvalvular intervention during septal myectomy effectively eliminated left ventricular outflow tract obstruction and provided high freedom from residual mitral regurgitation one year after surgery.