Modified extended septal myectomy for relief of left ventricular outflow tract obstruction in advanced Fabry cardiomyopathy: a case report

Fabry disease (FD), a rare X-linked lysosomal storage disorder caused by GLA gene mutations, leads to progressive glycosphingolipids accumulation and multi-organ dysfunction. Cardiac involvement in FD is the most common cause of mortality. We report a patient with predominant cardiac manifestations characterized by severe left ventricular hypertrophy (LVH) accompanied by left ventricular outflow tract (LVOT) obstruction and extensive myocardial fibrosis. Despite initiating enzyme replacement therapy, the patient's heart failure symptoms progressively worsened. No significant improvement was observed in LVH and LVOT. Consequently, a modified extended septal myectomy (MESM) was performed, resulting in remarkable hemodynamic improvement postoperatively. This report adds to the evidence supporting MESM in Fabry cardiomyopathy patients with LVOT obstruction. Learning objective 1. Fabry cardiomyopathy with left ventricular outflow tract (LVOT) obstruction is relatively rare and can easily be misdiagnosed as hypertrophic obstructive cardiomyopathy. 2. Modified extended septal myectomy can effectively alleviate the LVOT obstruction, relieve heart failure symptoms, and improve patient prognosis.