Efficacy and safety of radiofrequency ablation for hypertrophic obstructive cardiomyopathy: A systematic review and meta‐analysis

Abstract

Background: Although radiofrequency ablation is widely used in the treatment of arrhythmias, its role in septal reduction therapy of hypertrophic obstructive cardiomyopathy (HOCM) is unclear. This meta-analysis aimed to assess the efficacy and safety of radiofrequency septal ablation for HOCM.Hypothesis: Radiofrequency septal ablation is effective and safe for relieving obstruction and improving exercise capacity in patients with HOCM.Methods: A systematic review of eligible studies that reported outcomes of patients with HOCM who underwent radiofrequency septal ablation was performed using PubMed, Embase, Cochrane, ProQuest, Scopus, ScienceDirect, and Web of Science database. Pooled estimates were calculated using random-effects meta-analysis.Methodological quality was assessed using the Newcastle-Ottawa scale. Publication bias and sensitivity analyses were also performed.Results: Eight studies with 91 patients (mean follow-up 11.6 months) were included.The left ventricular outflow tract (LVOT) gradient at rest decreased significantly after radiofrequency septal ablation (pooled reduction: −58.8 mmHg; 95% confidence interval [CI] −64.3 to −53.5). A reduction was also found in the provoked LVOT gradient with a pooled reduction of −97.6 mmHg (95% CI: −124.4 to −87.1). An improvement of the New York Heart Association classification (mean: −1.4; 95% CI: −1.6 to −1.2) was found during follow-up. The change in septal thickness was minimal and not statistically significant. Two procedure-related deaths were documented, and complete heart block occurred in eight patients.Conclusions: Radiofrequency septal ablation is effective and safe for relieving LVOT obstruction and improving exercise capacity in patients with HOCM. K E Y W O R D S hypertrophic obstructive cardiomyopathy, meta-analysis, radiofrequency ablation, septal reduction therapy Haonan Yang and Yuan Yang contributed equally to this work.

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“…It leads to sustained improvement in exercise capacity, persistent reduction in LVOT gradient, and sustained improvement in the cardiac functions. It allows significant and sustained gradient reduction and symptomatic improvement of patients with severe hypertrophic cardiomyopathy [26,27].…”

Septal Reduction Using Transvenous Intramyocardial Cerclage Radiofrequency Ablation

“…This study shows that targeted cerclage intraseptal RF ablation accomplishes septal debulking via a transvenous approach, without inducing high-grade AV block. Endocardial RF ablation has been described previously for HCM treatment ( 23 , 24 , 25 , 26 , 27 , 28 ), and it usually, if not universally, induces high-grade AV conduction block requiring permanent pacing.…”

Cerclage Septal Ablation for Hypertrophic Cardiomyopathy

“…This modality has shown efficacy in limited case series, but it notably does not thin the septum significantly and can be associated with a high rate of atrioventricular conduction block. Long-term outcomes are not available ( 4 ).…”

“…It has also been recognized that the injury to the hypertrophied septum produced by endocardial radiofrequency ablation differs from the injury induced by alcohol infusion. In some patients, this could induce tissue edema that can result in a transient increase in wall thickness and an increase in the pressure gradient across the LV outflow tract ( 4 ). In the animals subjected to cerclage ablation, local edema led to an early increase in wall thickness in all hearts studied, with 2 of 6 animals showing a >50% increase.…”

“…An increase in wall thickness and LV outflow obstruction might be associated with serious clinical consequences among patients with severe degrees of resting obstruction. Among the 108 cases of endocardial radiofrequency ablation for HCM reported to date, 1 death was attributed to this complication ( 4 ).…”