Percutaneous transluminal septal myocardial ablation for hypertrophic obstructive cardiomyopathy: The Chinese experience in 119 patients from a single center

Background: Percutaneous transluminal septal myocardial ablation (PTSMA) has been introduced as an alternative treatment for hypertrophic obstructive cardiomyopathy (HOCM). We report on the acute, short- and long-term results of our experiences in 119 patients from a single center in China. Methods and results: PTSMA was performed in 119 patients with symptomatic HOCM (mean age 35.4±14.8 years, male 80, female 39). All patients had echocardiography performed prior to the procedure, 2-week post-PTSMA, and 6-month post-PTSMA, and 65 patients had echocardiography repeated at 2-year follow-up. The average left ventricular outflow tract (LVOT) gradient was 67.3±7.8 mm Hg before the procedure, and 15.9±6.8 mm Hg after the procedure (p<0.05). The thickness of interventricular septum (IVS) was 23.3±5.6 mm before the procedure, 18.6±4.8 mm 2-week post-PTSMA (p<0.05), and 16.8±3.4 mm 6-month post-PTSMA in all of the patients, and 15.6±3.1 mm 2-year post-PTSMA in 65 patients. The mean width of LVOT was 6.7±2.0 mm before the procedure, 8.2±3.4 mm 2-week post-PTSMA (p<0.05), 13.7±6.3 mm 6-month post-PTSMA and 15.1±2.4 mm 2-year post-PTSMA. The incidence of right bundle branch block development post-PTSMA was 52.9%, and three patients (2.5%) had complete heart block. There was no death. Conclusions: PTSMA is a promising non-surgical procedure for symptomatic patients with HOCM because of its low risk and its significant hemodynamic, echocardiographic and clinical improvement. The significant therapeutic remodeling period was up to 6 months rather than 2 years following the procedure.