Perioperative Myocardial Injury After Noncardiac Surgery

Study Questions:

What is the incidence of perioperative myocardial injury (PMI) and its association with 30-day and 1-year mortality?

Methods:

The investigators performed a prospective diagnostic study enrolling consecutive patients undergoing noncardiac surgery that had a planned postoperative stay of ≥24 hours and were considered at increased cardiovascular risk. All patients received a systematic screening using serial measurements of high-sensitivity cardiac troponin T (hs-cTnT) in clinical routine. PMI was defined as an absolute hs-cTnT increase of ≥14 ng/L from preoperative to postoperative measurements. Further, mortality was compared among patients with PMI not fulfilling additional criteria (ischemic symptoms, new electrocardiogram changes, or imaging evidence of loss of viable myocardium) required for the diagnosis of spontaneous acute myocardial infarction (AMI) versus those who did.

Results:

From 2014-2015, the study investigators included 2,018 consecutive patients undergoing 2,546 surgeries. Patients were 42% female with a median age of 74 years. PMI occurred after 397/2,546 surgeries (16%; 95% confidence interval [CI], 14-17%), and was accompanied by typical chest pain in 24/397 patients (6%) and any ischemic symptoms in 72/397 (18%). Crude 30-day mortality was 8.9% (95% CI, 5.7-12.0) in patients with PMI versus 1.5% (95% CI, 0.9-2.0) in patients without PMI (p < 0.001). Multivariable regression analysis showed an independent hazard ratio of 2.7 (95% CI, 1.5-4.8) for 30-day mortality. The difference was retained at 1 year with mortality rates of 22.5% (95% CI, 17.6-27.4) versus 9.3% (95% CI, 7.9-10.7). Thirty-day mortality was comparable among patients with PMI not fulfilling any other of the additional criteria required for spontaneous AMI (280/397, 71%) versus those with at least one additional criterion (10.4%, 95% CI, 6.7-15.7 vs. 8.7%, 95% CI, 4.2-16.7; p = 0.684).

Conclusions:

The authors concluded that PMI is a common complication following noncardiac surgery, and despite early detection during routine clinical screening, is associated with substantial short- and long-term mortality.

Perspective:

This prospective study reports that PMI is frequent after noncardiac surgery, and despite early detection during routine clinical screening, is associated with substantial short- and long-term mortality. Furthermore, mortality seems comparable in patients with PMI not fulfilling any other of the additional criteria required for spontaneous AMI versus those that do. The high incidence of PMI and the high mortality rate seen in this study suggests that the specific selection criteria used to identify high-risk patients (age 65 years or older, or pre-existing atherosclerotic disease) need to be validated in future randomized controlled trials testing the effect of active surveillance combined with an active response protocol on outcomes.

Keywords: Acute Coronary Syndrome, Chest Pain, Diagnostic Imaging, Electrocardiography, Geriatrics, Myocardial Infarction, Myocardial Ischemia, Myocardium, Perioperative Care, Risk Factors, Surgical Procedures, Operative, Troponin T


< Back to Listings