595 A Single Centre Experience of Septal Myectomy

Abstract

Septal myectomy remains the gold standard for treatment of severely symptomatic hypertrophic obstructive myopathy (HOCM). A retrospective study was performed to determine the efficacy of septal myectomy in reducing dynamic LVOT obstruction and evaluate the rate of complications associated with the procedure. Retrospective data from cardiac operations performed between 2000-2019 at Dunedin Public Hospital were obtained. Search terms used were septal myectomy and Morrow procedure. Twelve patients underwent septal myectomy between the years 2000-2019 however there was insufficient clinical information for two patients so only ten were included in this study. Out of the ten patients analysed, nine patients had HOCM and one patient had a subaortic membrane. All patients had reductions in LVOT velocities, peak LVOT gradients and septal thickness shown on ECHOs performed within 12 months of surgery. No patients required a permanent pacemaker after the procedure and there were no mortalities 30 days post operatively. All patients had a downgrading of NYHA classification to either II or I. One patient required alcohol septal ablation at 2 years post operatively. Despite only performing a small number of myectomies in the last two decades, complication rates were low and effectiveness, in terms of both symptomatology and ECHO parameters, was found to be high. Septal myectomy should continue to be performed for HOCM patients with severe symptoms that are refractory to medical therapy. It is a safe procedure with measurable improvements in morbidity for patients.