Comparison of acute and chronic myocardial injury in noncardiac surgical patients

Purpose Perioperative myocardial injury is a predictor of postoperative mortality, but the clinical impact of chronic injury during the perioperative period has not been fully investigated. This study aimed to evaluate chronic myocardial injury during the perioperative period in comparison with normal and acute myocardial injury. Methods Patients with serial cardiac troponin measurements before and within 30 days following noncardiac surgery were divided into three groups: normal, acute injury, and chronic injury groups. Acute and chronic myocardial injuries were stratified according to 2018 recommendations by the International Federation of Clinical Chemistry and Laboratory Medicine's Task Force on Clinical Applications of Bio-Markers. Thirty-day and one-year mortalities after surgery were compared. Results Of the 22,969 patients reviewed, 17,671 (76.9%) were classified into the normal, 5,179 (22.5%) into the acute injury, and 119 (0.5%) into the chronic injury groups. The acute and chronic injury groups had higher 30-day mortalities compared with the normal group (0.8% vs. 8.0%; hazard ratio [HR], 11.00; 95% confidence interval [CI], 9.05-13.37; P < 0.001 and 0.8% vs. 7.6%; HR, 10.55; 95% CI, 5.37-20.72; P < 0.001, respectively). In a direct comparison between the acute and chronic injury groups using an inverse probability of weighting adjustments, the 30-day and one-year mortalities were not significantly different. Conclusion Chronic myocardial injury during the perioperative period may show similar clinical impacts on postoperative mortality compared with acute injury. Further studies are needed.