Surgical septal myectomy for relief of dynamic obstruction in Anderson-Fabry Disease

Patients with Anderson-Fabry Disease (AFD) and severe left ventricular hypertrophy complicated by left ventricular outflow tract (LVOT) obstruction may benefit from surgical septal myectomy (SSM). Mid- and late outcomes following surgery have not been established, and we sought to better characterize postoperative outcomes following septal myectomy. Between January 2011 and June 2017, 7 patients (6 females) with AFD underwent SSM. The median (range) age at the time of surgery was 53 (37-72) years; 4 patients had a positive family history of AFD and a preoperative diagnosis of AFD. Extracardiac features suggestive of AFD were present in 3 patients and all but 1 (female) had reduced α-galactosidase A activity. All patients had severe left ventricular hypertrophy and LVOT obstruction on transthoracic echocardiography. Preoperatively, all patients were severely symptomatic with New York Heart Association (NYHA) class III symptoms. There was no early mortality following surgery. The median in-hospital length of stay was 5 (4-7) days with 6 patients reporting NYHA class II or less symptoms at 3 month follow-up. Long-term outcomes were favorable with 4 patients reporting sustained NYHA class II or less symptoms, but 2 patients had recurrence of NYHA class III symptoms without evidence of recurrent LVOT obstruction. In conclusion, SSM appears to provide favorable short- and long-term relief of severe, symptomatic LVOT obstruction but may not alter progression of Fabry cardiomyopathy.