Abstract 1699: Outcome Of Percutaneous Septal Ethanol Ablation For Obstructive Hypertrophic Cardiomyopathy
Background. Although percutaneous alcohol septal ablation has emerged as an alternative therapy for obstructive hypertrophic cardiomyopathy (HCM), questions remain about its safety and long-term clinical efficacy. This study therefore was undertaken to examine the outcome of septal ablation performed at a tertiary HCM referral center.
Methods and Results. All patients with severe drug refractory symptoms due to obstructive HCM seen at Mayo Clinic were offered septal reduction therapy of either septal myectomy or septal ablation. 140 patients (mean age, 64 yrs; 39% men) chose to undergo septal ablation. There were no periprocedural deaths. Pacemaker dependency occurred in 20.0%. Five-year survival free of all mortality was 89.1% (95% confidence interval or CI, 80.3 to 97.8%), and was no different from the expected survival of a similar general U.S. population (89%, p=0.13). At follow-up, symptomatic improvement (≥1 functional class) occurred in 114 of the surviving patients (81%), including 70 patients (50%) who became asymptomatic. Nine patients (6.4%) later required surgical myectomy. Overall, the five-year survival free of the combined endpoint of death or class III/IV symptoms following septal ablation was 68.3% (95% CI, 53.7 to 82.8%). This survival is in contrast to an 81%, five-year survival free of death or Class III/IV symptoms in a cohort of patients undergoing myectomy at our institution.
Conclusions. Septal ablation is a safe, efficacious percutaneous procedure if performed in an experienced institution and may improve symptoms in a subset of patients with obstructive HCM. In this study, there was no impairment of longevity following septal ablation. However, its major limitation is a relatively lower clinical efficacy in comparison to surgical myectomy.