Acute and long-term results after transcoronary ablation of septal hypertrophy (TASH). Catheter interventional treatment for hypertrophic obstructive cardiomyopathy.

Abstract

To evaluate acute and long-term symptomatic, haemodynamic (at rest and during exercise) and electrophysiological results of transcoronary ablation of septal hypertrophy (TASH), a catheter interventional treatment for hypertrophic obstructive cardiomyopathy. Sixty-two transcoronary ablations of septal hypertrophy were performed by injection of 4.6+/-2.6 ml 96% ethanol into septal branches in 50 patients with hypertrophic obstructive cardiomyopathy and severe symptoms. Serial left and right heart catheterization, transoesophageal echocardiography and electrophysiological investigations were repeated 2 weeks and 7+/-1 months (n=37) after intervention. Transcoronary ablation of septal hypertrophy led to a reduction in septal thickness, sustained elimination of the outflow obstruction (51+/-41 vs 6+/-10 mmHg at rest, P<0.001; 134+/-48 vs 28+/-32 mmHg, P<0.001, post-extrasystolic), a decrease in left ventricular filling pressures at rest and during exercise and a pronounced clinical improvement. There was no evidence for the creation of an arrhythmogenic substrate as assessed by serial programmed electrical stimulation in 39 patients. However, permanent high-grade atrioventricular block occurred in 17% of the patients. There were two early, but no late deaths during a mean follow-up time of 10. 6+/-5.6 months. Transcoronary ablation of septal hypertrophy is a promising new treatment for hypertrophic obstructive cardiomyopathy in patients with severe symptoms. It should now be compared with alternative treatment strategies in prospective randomized studies.