Objective: Hypertrophic obstructive cardiomyopathy is still a troublesome clinical problem, lack of good treatment method. We use transcatheter chemical myocardial ablation to treat hypertrophic obstructive cardiomyopathy and analysis 25 cases results, to search a novel technique for hypertrophic obstructive cardiomyopathy.Method: From Nov.1996 to Oct.2001 25patients with symptomitical and drug resistents hypertrophic obstructive cardiomyopathy acccepted a nonsurgical treatment, that is percutaneous transseptal myocardial ablation (PTSMA) in our department including 16 males and 9 females, with mean age 44.1 years All patients meet echocardiography diagnosis criterias of hypertrophic obstructive cardiomyopathy, With clinical symptoms of angiana pectors, sycope, short breath etc. No improvement to long term Medical theraphy, rest pressure left ventricular outflow tract gradients over 30 mmHg, or over 50mmHg during provocal test either by invasion or indirect measurement with Doppler echocardiography, 5 patients accepted treatment With Sigwart’s method as previous described, other 20 cases with pigtail catheter left ventricular Continuous curve to measure left ventricular outflow tract gradient, percutaneous insert 1.5mm to 2.0mm balloon catheter into first septal branch of left anterior descending coronary artery, via inflated balloon , inject 3-5ml absolute alcohol into the artery , keep inflating balloon for other 5 minutes continue monitoring pressure gradients and ECG, temporary pacemaker and defibrillator were stand by.Results: All patients, left ventricular outflowtract gradients were significantly reduced, more than 50%, 6 cases occurred serve bradycardia, hypotension need immediate administration, 17 cases with trancient complete right branch block, and in five cases, with permonant complete right branch block,2 cases with transient complete AV block. In follow up, symptom and life quality of all patients were dramitically improved, in first month post procedure, septum thickness reduction, 6mm in averag
