Background: Alcohol septal ablation (ASA) is an emerging percutaneous technique to treat patients with hypertrophic obstructive cardiomyopathy (HOCM) and refractory to medical therapy. ASA in Thailand has never been reported.
Material and Method: The authors reviewed clinical and hemodynamic data of four patients with HOCM before and after ASA performed between November 2007 and May 2008 in Songklanagarind Hospital.
Results: ASA without myocardial contrast echocardiography was done successfully in all four patients with HOCM and refractory to medical therapy. The authors used the anatomical characteristics of vessel and pressure-guided technique to identify the optimal septal perforator artery. The averages of left ventricular outflow tract (LVOT) peak/mean pressure gradients (PPG/MPG) were 105/56 before and 32/18 mmHg immediately after ASA, consecutively. There were further falls in LVOT PPG and MPG to averages of 14 and 8.5 mmHg respectively at 6-12 week follow-up. The mean absolute alcohol volume was 2.5 + 0.41 ml. Transient complete atrioventricular block occurred in one patient. All patients reported substantial symptomatic improvement.
Conclusion: The authors reported the first cases series of HOCM patients who underwent ASA in Thailand. ASA without myocardial contrast echocardiography in carefully selected patient is feasible, effective, and safe.

Keyword : Hypertrophic obstructive cardiomyopathy, Alcohol septal ablation