Comparison of Percutaneous Coronary Intervention-Related Adverse Cardiac Outcomes in Patients With in-stent vs de novo Chronic Total Occlusion: A Systematic Review and Meta-Analysis.

Contemporary literature reveals a range of cardiac complications in patients who receive the percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). This study compared the adverse cardiac outcomes and procedural/technical success rates between the patients groups of in-stent (IS) CTO PCI and de novo CTO PCI. This systematic review and meta-analysis compared odds for primary (all-cause mortality, MACE, cardiac death post PCI, stroke) and secondary (bleeding requiring blood transfusion, ischemia-driven target-vessel revascularization, PCI procedural success, PCI technical success, and target-vessel MI) endpoints between 2734 patients who received PCI for IS CTO and 17,808 for de novo CTO. Odds ratios for outcome variables were calculated within 95% confidence intervals (CIs) via the Mantel-Haenszel method. The pooled analysis was undertaken for observational (retrospective/prospective) single- and multicentered studies published between January 2005 and December 2021. We found 57% higher, 166% higher, 129% higher, and 57% lower odds for MACE (OR: 1.57, 95% CI 1.31, 1.89, P < 0.001), ischemia-driven target-vessel revascularization (OR: 2.66, 95% CI 2.01, 3.53, P < 0.001), target-vessel myocardial infarction (MI) (OR: 2.29, 95% CI 1.70, 3.10, P < 0.001), and bleeding requiring blood transfusion (OR: 0.43, 95% CI 0.19, 1.00, P = 0.05), respectively, in patients with IS CTO PCI as compared to that of the de novo CTO PCI. No statistically significant differences between the study groups were recorded for the other primary/secondary outcome variables. The findings from this study indicated a high predisposition for MACE, ischemia-driven target-vessel revascularization, target vessel MI, and a lower incidence of bleeding episodes among IS CTO PCI patients as compared to those with de novo CTO PCI. The prognostic outcomes in CTO PCI cases require further investigation with randomized controlled trials.