Impact of periprocedural myocardial injury on long-term clinical outcomes of chronic total occlusion patients undergoing percutaneous coronary intervention: a systematic review and meta-analysis

Background: Several studies have evaluated the long-term clinical outcomes of periprocedural myocardial injury for chronic total occlusions patients. However, the results of these studies were inconsistent. To determine whether the periprocedural myocardial injury has adverse effects on long-term clinical outcomes in chronic total occlusion patients undergoing percutaneous coronary intervention. Methods: We searched Cochrane Library, PubMed, and Embase for eligible articles from their date of inception up to March 2019. Long-term clinical outcomes included major adverse cardiac events, all-cause death, cardiac death, myocardial infarction, and target vessel revascularization. Odds ratios with 95% confidence intervals were calculated as summary statistics by using Review Manager software. Results: A total of 8 observational studies involving 5879 chronic total occlusions patients were included in this meta-analysis. These results of this meta-analysis indicated that periprocedural myocardial injury was associated with a higher risk of major adverse cardiac events (odds ratio, 1.94; 95% confidence interval, 1.22-3.08; P = 0.005), a higher risk of all-cause death (odds ratio, 1.30; 95% confidence interval, 1.02-1.64; P = 0.03), a higher risk of cardiac death (odds ratio, 2.59; 95% confidence interval, 1.41-4.78; P = 0.002), a higher risk of myocardial infarction (odds ratio, 3.07; 95% confidence interval, 1.90-4.98; P < 0.00001), and a higher risk of target vessel revascularization (odds ratio, 2.07; 95% confidence interval, 1.35-3.16; P=0.0008) than non-periprocedural myocardial injury. Conclusion: Periprocedural myocardial injury was associated with significantly increased risk of major adverse cardiac events, all-cause death, cardiac death, myocardial infarction, and target vessel revascularization in chronic total occlusion patients undergoing percutaneous coronary intervention at long-term follow-up.