Seung‐Hwa Lee

Background Cardiac complications are associated with perioperative mortality, but perioperative adverse cardiac events (PACEs) that are associated with long‐term mortality have not been clearly defined. We identified PACE as a composite of myocardial infarction, coronary revascularization, congestive heart failure, arrhythmic attack, acute pulmonary embolism, cardiac arrest, or stroke during the 30‐day postoperative period and we compared mortality according to PACE occurrence. Methods and Results From January 2011 to June 2019, a total of 203 787 consecutive adult patients underwent noncardiac surgery at our institution. After excluding those with 30‐day mortality, mortality during a 1‐year follow‐up was compared. Machine learning with the extreme gradient boosting algorithm was also used to evaluate whether PACE was associated with 1‐year mortality. After excluding 1203 patients with 30‐day mortality, 202 584 patients were divided into 7994 (3.9%) patients with PACE and 194 590 (96.1%) without PACE. After an adjustment, the mortality was higher in the PACE group (2.1% versus 7.7%; hazard ratio [HR], 1.90; 95% CI, 1.74–2.09; P <0.001). Results were similar for 7839 pairs of propensity‐score‐matched patients (4.9% versus 7.9%; HR, 1.64; 95% CI, 1.44–1.87; P <0.001). PACE was significantly associated with mortality in the extreme gradient boostingmodel. Conclusions PACE as a composite outcome was associated with 1‐year mortality. Further studies are needed for PACE to be accepted as an end point in clinical studies of noncardiac surgery.