Percutaneous septal ablation in hypertrophic obstructive cardiomyopathy: long-term follow-up

Background and objective: Persisting disabling symptoms despite optimal medical treatment in patients with hypertrophic cardiomyopathy and significant outflow tract obstruction prompt surgical or interventional therapy targeted at relief of obstruction. While surgical treatment was introduced more than 40 years ago, there are only a few data on the long-term results of percutaneous septal ablation. This study gives the results of a large number of patients wieth hypertrophic obstructive cardiomyopathy (HOCM) who underwent septal ablation in our institution. Patients and methods: 347 patients (156 females, 191 males, 54 +/- 15 years) in NYHA functional class III or IV, or in class II but with evidence of more severe limitation on exercise testing, underwent percutaneous transluminal septal myocardial ablation (PTSMA). Mortality and morbidity, as well as clinical and echocardiographic parameters were assessed during follow-up, either at our institution, or by the referring cardiologist. Results: During an average follow-up of 58 +/- 35 months the overall mortality was about 1,8% per year, with a cardiovascular-related mortality of about 1% per year. 8% of patients needed a second procedure. A significant and sustained improvement of symptoms (89% patients were in NYHA class I or II a follow-up) and obstruction were demonstrated (74% of patients were free from obstruction at rest, 60% did not exhibit provokable gradients). Supraventricular arrhythmias, especially atrial fibrillation, were observed in 12% of patients. Conclusion: Percutaneous septal ablation provides significant and sustained beneficial effects on symptoms and echocardiographic variables, without evidence of an excess mortality. But independently of the clinical success of the procedure persistence of the underlying structural heart disease should be kept in mind. Periodic re-evaluation is mandatory to identify and treat high-risk patients.