OBJECTIVETo evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM).

METHODSFifteen symptomatic, drug-refractory patients with HOCM underwent PTSMA procedures with application of a myocardial contrast echocardiography (MCE) intra-procedure. Before and after the procedure, clinical evaluations were obtained in all patients, who were followed up for a mean period of 8.6 +/- 3.8 (6-20) months.

RESULTSImmediate left ventricular outflow tract gradient (LVOTG) reduction was achieved (77.93 +/- 22 mm Hg vs 14.8 +/- 15 mm Hg, P < 0.0001) after the procedure with a mean decrease of 5.75 +/- 2.87 mm Hg of left ventricular end diastolic pressure (P < 0.001). Follow up results revealed that ventricular remodelling occurred mainly 1-3 months after the procedure, but without evidence of ventricular dilation and contract dysfunction. Heart function (NYHA) was greatly improved (3.4 +/- 0.5 vs 1.1 +/- 0.4, P < 0.001) and exercise endurance increased. A renewed increase of LVOTG was found in 2 patients during follow-up.

CONCLUSIONSLVOTG was greatly decreased in HOCM patients undergoing a PTSMA procedure, and their symptoms were greatly improved without cardiac complications during follow-up. Sub-selection and reopening of target vessels were the causes of renewed increase of LVOTG, and this can be avoided with the accumulation of experience. This is a promising method for the treatment of symptomatic patients with HOCM.