Percutaneous transluminal septal myocardial ablation for hypertrophic obstructive cardiomyopathy: long term follow up of the first series of 25 patients

Objective-To determine the long term outcome in patients treated with percu taneous transluminal septal myocardial ablation (PTSMA) for hypertrophic ob structive cardiomyopathy (HOCM). Design and setting-Observational, single centre study. Patients-25 patients (13 women, 12 men, mean (SD) age 54.7 (15.0) years) wi th drug treatment resistant New York Heart Association (NYHA) class 2.8 (0. 6) symptoms attributed to a high left ventricular outflow gradient (LVOTG) and a coronary artery anatomy suitable for intervention. Intervention-PTSMA by injection of 4.1 (2.6) ml of alcohol (96%) into 1.4 ( 0.6) septal perforator arteries to ablate the hypertrophied interventricula r septum. Outcome measures-During in-hospital follow up, enzyme rise, the frequency o f atrioventricular conduction lesions requiring permanent DDD pacing, and i n-hospital mortality were assessed. Long term follow up (30 (4) months, ran ge 24-36 months) included symptoms, echocardiographic measurements of left atrial and left ventricular dimensions and function, and LVOTG. Results-Mean postinterventional creatine kinase rise was 780 (436) U/l. Dur ing PTSMA 13 patents developed total heart block, permanent pacing being ne cessary in five of them. One 86 year old patient died from ventricular fibr illation associated with intensive treatment (beta mimetic and theophylline ) for coexistent severe obstructive airway disease, After three months, thr ee patients underwent re-PTSMA because of a dissatisfactory primary result, leading to LVOTG elimination in all of them. During long term follow up, L VOTG showed sustained reduction (3 (6) mm Hg at rest and 12 (19) mm Hg with provocation) associated with stable symptomatic improvement (NYHA class 1. 2 (1.0)) and without significant global left ventricular dilatation. Conclusions-PTSMA is an effective non-surgical technique for reduction of s ymptoms and LVOTG in HOCM. Prospective, long term observations of larger po pulations are necessary in order to determine the definitive significance o f the procedure.