Chest pain in patients recovering from noncardiac surgery: A retrospective analysis

High-sensitivity troponin T levels before and after cardiac surgery and the 30-day mortality: a retrospective cohort study

Background

The suggested threshold level of cardiac troponin T elevation after cardiac surgery is not very clear, and the values recommended by various guidelines and literature reports are quite different.

Methods

In this retrospective cohort study, we collected clinical data of patients who underwent heart surgery at Tsinghua University First Hospital between January 2015 and December 2022. Using the high-sensitivity cardiac troponin T levels (reference upper limit: 14 ng/L) measured at 1-3 days postoperation, the relationship between the cardiac troponin T level and the 30-day mortality risk was evaluated using Cox regression analysis.

Results

Among the 3,128 patients included in this study, the types of operations mainly consisted of coronary artery bypass graft (CABG, 1,164, 37.2%), aortic valve replacement (AVR, 735, 23.5%), and other cardiac operations (1,229, 39.3%). Within 30 days postoperation, 57 patients (1.8%) died and 72 patients (2.3%) developed major vascular complications. In patients undergoing CABG or AVR, the cardiac troponin T threshold level measured within one day postoperation related to an increased 30-day mortality was determined to be 3,012 ng/L (95% CI: 1,435-3,578 ng/L), which is 218 times higher than the reference upper limit. In patients undergoing other cardiac operations, this threshold was 5,876 ng/L (95% CI: 2,458-8,119 ng/L), which is 420 times higher than the reference upper limit.

Conclusion

The high-sensitivity cardiac troponin T level associated with an increased 30-day mortality risk after cardiac surgery is significantly higher than the current recommendations for defining clinically important perioperative myocardial injury.

Perioperative strategies to reduce risk of myocardial injury after non-cardiac surgery (MINS): A narrative review

Myocardial injury is a frequent complication of surgical patients after having non-cardiac surgery that is strongly associated with perioperative mortality. While intraoperative anesthesia-related deaths are exceedingly rare, about 1% of patients undergoing non-cardiac surgery die within the first 30 postoperative days. Given the number of surgeries performed annually, death following surgery is the second leading cause of death in the United States. Myocardial injury after non-cardiac surgery (MINS) is defined as an elevation in troponin concentrations within 30 days postoperatively. Although typically asymptomatic, patients with MINS suffer myocardial damage and have a 10% risk of death within 30 days after surgery and excess risks of mortality that persist during the first postoperative year. Many factors for the development of MINS are non-modifiable, such as preexistent coronary artery disease. Preventive measures, systematic approaches to surveillance and treatment standards are still lacking, however many factors are modifiable and should be considered in clinical practice: the importance of hemodynamic control, adequate oxygen supply, metabolic homeostasis, the use of perioperative medications such as statins, anti-thrombotic agents, beta-blockers, or anti-inflammatory agents, as well as some evidence regarding the choice of sedative and analgesic for anesthesia are discussed. Also, as age and complexity in comorbidities of the surgical patient population increase, there is an urgent need to identify patients at risk for MINS and develop prevention and treatment strategies. In this review, we provide an overview of current screening standards and promising preventive options in the perioperative setting and address knowledge gaps requiring further investigation.