NEW YORK (Reuters Health) – In patients with symptomatic hypertrophic obstructive cardiomyopathy, alcohol septal ablation results in sustained clinical and hemodynamic improvement, according to a prospective study spanning more than a decade.

“Our biggest finding was the lasting nature of symptomatic improvement without many deaths long-term,” senior author Dr. William H. Spencer, III, at the Medical University of South Carolina in Charleston, told Reuters Health.

The study included 629 consecutive patients (mean age 54, range 13 to 90 years) treated at Dr. Spencer’s institution and at the Methodist-DeBakey Heart Center in Houston from November 1996 to August 2006 and followed up to March 2007.

The procedure was successful in all but 10 cases (98.4% success rate), the authors report in the October issue of the Journal of the American College of Cardiology: Cardiovascular Interventions.

In-hospital complications included 6 deaths, coronary dissections in 8, worsening mitral valve regurgitation necessitating mitral valve replacement in 2, and atrioventricular or complete heart block resulting in permanent pacemaker implantation in 52 patients.

During median follow-up of 4.5 years, mean New York Heart Association functional class decreased from 2.8 to 1.2, Canadian Cardiovascular Society angina score fell from 2.1 to 1.0, and treadmill exercise time increased from 4.8 to 8.2 minutes (p< 0.001 for all three comparisons). According to the research team, “The left ventricular outflow tract gradient, both resting and provoked, was markedly reduced at 3 months and continued to decrease during the 10-year period.” Septal thickness was reduced by approximately half. Ninety-one repeat procedures were performed in 81 patients with persistent or recurrent symptoms and dynamic obstruction, with a success rate of 94%. In addition, 25 patients underwent surgical myectomy and 11 underwent mitral valve or aortic valve replacement. Survival estimates were 97% at 1 year, 92% at 5 years, and 89% at 8 years, rates that are similar to those reported after surgical myectomy, the authors report. The authors conclude: “The present study shows that alcohol septal ablation is a safe and efficacious treatment for symptomatic hypertrophic obstructive cardiomyopathy.” “Alcohol septal ablation is a suitable alternative to surgery,” Dr. Spencer added. However, “patients with associated valvular or extensive coronary disease are not candidates.” In the near future, “we hope to compare the results in the young vs old patients. Also, we will report a low sudden death rate in high-risk patients following alcohol septal ablation.” Reference:
Journal of the American College of Cardiology: Cardiovascular Interventions, October 2008