Objective: To assess the acute and mid-term results of cardiac function improvements and left ventricular outflow tract gradient (LVOTG)changes in 30 patients displaying hypertrophic obstructive cardiomyopathy (HOCM) treated with percutaneous transluminal septal myocardial ablation(PTSMA). Methods: PTSMA was intended for 32 patients comprising of 13 women and 19 men(average years being 54.1 ± 15.5) to be treated in accordance with the following inclusion criteria: The New York Heart Association(NYHA) definition for cardiac functional class III or IV ,or class II but for whom medical therapies were not tolerated or with syncope; intraventricular septal(IVS) and left ventricular posterior wall(LVPW) hypertrophy asymmetrically associated with ratio of IVS to LVPW≥1.3 and LVOTG≥50 mm Hg at rest or ≥100 mm Hg at provocation(Valsalva maneuver). The target vessels were determined by coronary arteriography that demonstrated more than one septal branch and probatory balloon occlusion produced greater than 50% decrease of LVOTG . Once the target vessel established, the alcohol was administrated into septal ventricular via over-the-wire balloon. LVOTG was assessed by means of echocardiography measurements immediately after procedure and 3 months. Simultaneously, cardiac function class was also evaluated. Results: Two patients were abandoned prior to intervention due to inappropriate septal target vessels and DDD Pacemakers were chosed. Immediately after the procedure, resting LVOTG was reduced from 73.8 ± 35.5 to 16.6 ± 7.8 mmHg, at provocation LVOTG from 149.3 ± 42.5 to 61.9 ± 43.0 mmHg(P < 0.0001 each) by echocardiography measurements. After 3 months, the mean New York Heart Association class was reduced from 2.8 ± 0.6 to 1.1 ± 1.0(P < 0.0001) and the LVOTG also remained decrease(28.5 ± 6.4 mmHg at rest and 75.3 ± 11.6 mmHg at provocation). Conclusion: PTSMA is a promising nonsurgical technique for relief of symptoms and reduction of LVOTG in hypertrophic obstructive cardiomyopathy. Objective: To assess the acute and mid-term results of cardiac function improvements and left ventricular outflow tract gradient (LVOTG) changes in 30 patients displaying hypertrophic obstructive cardiomyopathy (HOCM) treated with percutaneous transluminal septal myocardial ablation (PTSMA). Methods: PTSMA was intended for 32 patients comprising 13 women and 19 men (average years being 54.1 ± 15.5) to be treated in accordance with the following inclusion criteria: The New York Heart Association (NYHA) definition for cardiac functional class III or IV, or class II but for whom medical therapies were not tolerated or with syncope; intraventricular septal (IVS) and left ventricular posterior wall (LVPW) hypertrophy asymmetrically associated with ratio of IVS to LVPW ≥1.3 and LVOTG ≥50 mm Hg at rest or ≥100 mm Hg at provocation (Valsalva maneuver). The target vessels were determined by coronary arteriography that demonstrated more than one septal branch and probatory balloon occlusion pro Once the target vessel established, the alcohol was administrated into septal ventricular via over-the-wire balloon. LVOTG was assessed by means of echocardiography measurements immediately after procedure and 3 months. Simultaneously, cardiac function class Immediately after the procedure, resting LVOTG was reduced from 73.8 ± 35.5 to 16.6 ± 7.8 mmHg, at provocation LVOTG from 149.3 ± 42.5 to 61.9 ± 43.0 mmHg (P <0.0001 each) by echocardiography measurements. After 3 months, the mean New York Heart Association class was reduced from 2.8 ± 0.6 to 1.1 ± 1.0 (P <0.0001) and the LVOTG also remained decrease (28.5 ± 6.4 mmHg at rest and 75.3 ± 11.6 mmHg at provocation). Conclusion: PTSMA is a promising nonsurgical technique for relief of symptoms and reduction of LVOTG in hypertrophic obstacle ructive cardiomyopathy.