Impact of CTO Revascularization on Sudden Cardiac Death and/or Ventricular Arrhythmias: A Meta-Analysis of Observational Studies

Introduction: The presence of a chronic total occlusion (CTO) has been associated with increased risk of sudden cardiac death (SCD) and/or ventricular arrhythmias (VAs). This study aimed to evaluate the impact of CTO revascularization on SCD and/or VAs. Methods: A systematic review of the literature was performed to identify studies evaluating the association between CTO revascularization and risk of SCD and/or VAs. Results: Six studies were included in the final meta-analysis. The total sample size included 2,017 participants for the assessment of the primary outcome of interest and 868 participants for the assessment of the secondary outcome of interest. In 5 studies examining the association between CTO revascularization and risk of SCD and/or VAs, CTO revascularization was not associated with a statistically significant reduction in the risk of SCD and/or VAs (HR: 0.78; 95% CI: 0.38 to 1.60; p = 0.50, I2 = 87%). Conversely, in 2 studies examining the association between IRA-CTO revascularization and risk of SCD and/or VAs, IRA-CTO revascularization was associated with 79% lower risk of SCD and/or VAs (HR: 0.21; 95% CI: 0.10 to 0.43; p < 0.0001, I2 = 0%). Discussion: CTO revascularization overall was not associated with a lower risk of SCD and/or VAs. In contrast, IRA-CTO revascularization was associated with a lower risk of SCD and/or VAs. However, the study has several limitations, primarily due to the observational nature of the included studies. Conclusion: Successful revascularization of an IRA-CTO should be attempted to reduce the burden of VAs and reduce the risk of SCD.