Updated meta-analysis of septal alcohol ablation versus myectomy for hypertrophic cardiomyopathy

Objectives: The purpose of this study was to perform a systematic review and meta-analysis of comparative studies to compare outcomes of septal ablation (SA) with septal myectomy (SM) for treatment of hypertrophic obstructive cardiomyopathy (HOCM).

Background: SM is considered the gold standard for treatment of HOCM. However, SA has emerged as an attractive therapeutic alternative.

Methods: A Medline search using standard terms was conducted to determine eligible studies. Due to a lack of randomized control trials, we included observational studies for review.

Results: Twelve studies were found eligible for review. No significant differences between short-term (risk difference [RD]: 0.01; 95% confidence interval [CI]: -0.01 to 0.03) and long-term mortality (RD: 0.02; 95% CI: -0.05 to 0.09) were found between the SA and SM groups. In addition, no significant differences could be found in terms of post-intervention functional status as well as improvement in New York Heart Association functional class, ventricular arrhythmia occurrence, re-interventions performed, and post-procedure mitral regurgitation. However, SA was found to increase the risk of right bundle branch block (RBBB) (pooled odds ratio [OR]: 56.3; 95% CI: 11.6 to 273.9) along with need for permanent pacemaker implantation post-procedure (pooled OR: 2.6; 95% CI: 1.7 to 3.9). Although the efficacy of both SA and SM in left ventricular outflow tract gradient (LVOTG) reduction seems comparable, there is a small yet significantly higher residual LVOTG amongst the SA group patients as compared with the SM group patients.

Conclusion: SA does seem to show promise in treatment of HOCM owing to similar mortality rates as well as functional status compared with SM; however, the caveat is increased conduction abnormalities and a higher post-intervention LVOTG. The choice of treatment strategy should be made after a thorough discussion of the procedures with the individual patient.