Early and long-term results of non-surgical septal reduction in patients with hypertrophic cardiomyopathy

Background: Non-surgical septal reduction (NSMR) is a new method of treatment in patients with hypertrophic obstructive cardiomyopathy (HOCM). The long-term outcome of patients undergoing this procedure has not yet been well established. Aim: To assess the short- and long-term results of NSMR in HOCM. Methods: Early and late (3-year) outcome after NSMR was assessed in 59 and 44 consecutive patients with HOCM, respectively. Control out-patient visits were scheduled 3, 6, and 12 months after NSMR, and annually thereafter. All patients had repeated ECG, echocardiography, 24-hour ambulatory ECG monitoring and spiro-ergometric tests. Results: Left ventricular outflow tract (LVOT) gradient, measured invasively directly after the procedure, decreased from 79.5±29.6 to 26.2±18.5 mmHg (p 2 increased from 14.1±3.8 ml/kg/min before NSMR to 23.2±6.2 three years later, p=0.02). Favourable LV remodelling was observed, causing LVOT dilatation and an increase in LV diastolic volume. Conclusions: Because NSMR causes a significant reduction of LVOT gradient, an increase in physical capacity in >80% of patients and the long-term follow-up is uneventful, it may be regarded as an alternative procedure to myectomy in the treatment of patients with HOCM.