Outcomes of Patients With Hypertrophic Obstructive Cardiomyopathy and Pacemaker Implanted After Alcohol Septal Ablation
Abstract
Background: Atrioventricular block is a frequent major complication after alcohol septal ablation (ASA). Objectives: The aim of this study was to evaluate the outcomes of patients with implanted permanent pacemaker (PPM) related to a high-grade atrioventricular block after ASA for hypertrophic obstructive cardiomyopathy.
Methods: We used a multinational registry (the Euro-ASA registry) to evaluate the outcome of patients with PPM after ASA. Results: A total of 1,814 patients were enrolled and followed up for 5.0 +- 4.3 years (median = 4.0 years).
A total of 170 (9.4%) patients underwent PPM implantation during the first 30 days after ASA. Using propensity score matching, 139 pairs (n = 278) constituted the matched PPM and non-PPM groups.
Between the matched groups, there were no long-term differences in New York Heart Association functional class (1.5 +- 0.7 vs 1.5 +- 0.9, P = 0.99) and survival (log-rank P = 0.47). Patients in the matched PPM group had lower long-term left ventricular (LV) outflow gradient (12 +- 12 mm Hg vs 17 +- 19 mm Hg, P < 0.01), more pronounced LV outflow gradient decrease (81% +- 17% vs 72% +- 35%, P < 0.01), and lower LV ejection fraction (64% +- 8% vs 66% +- 8%, P = 0.02) and were less likely to undergo reintervention (re-ASA or myectomy) (log-rank P = 0.02).
Conclusions: Patients with hypertrophic obstructive cardiomyopathy treated with ASA have a 9% probability of PPM implantation within 30 days after ASA. In long-term follow-up, patients with PPM had similar long-term survival and New York Heart Association functional class but lower LV outflow gradient, a more pronounced LV outflow gradient decrease, a lower LV ejection fraction, and a lower likelihood of reintervention compared with patients without PPM.