• Jonathan D Knott, Laura De Michieli, Olatunde Ola, Ashok Akula, Ramila A Mehta, David O Hodge, Tahir Tak, Charles Cagin, Rajiv Gulati, Allan S Jaffe, and Yader Sandoval.
• Department of Internal Medicine, Mayo Clinic, Rochester, MN.
• Am. J. Med. 2023 Jul 1; 136 (7): 687693.e2687-693.e2.

BackgroundDifferentiating type 2 myocardial infarction from myocardial injury can be difficult. In addition, the presence of objective evidence of myocardial ischemia may facilitate identification of high-risk type 2 myocardial infarction patients.MethodsThis was an observational cohort study of adult emergency department patients undergoing high-sensitivity cardiac troponin T (hs-cTnT) measurement. Patients with ≥1 hs-cTnT >99th percentile were adjudicated following the Fourth Universal Definition of Myocardial Infarction. Patients were categorized as "subjective type 2 myocardial infarction" when ischemic symptoms were the lone criteria supporting type 2 myocardial infarction, or "objective type 2 myocardial infarction" when there was ≥1 objective clinical feature (electrocardiography, imaging, angiography) of acute myocardial ischemia. The primary outcome was mortality.ResultsA total of 857 patients were included, among which 55 (6.4%) were classified as subjective type 2 myocardial infarction, 36 (4.2%) as objective type 2 myocardial infarction, and 702 (82%) as myocardial injury. Those with objective type 2 myocardial infarction had a higher risk of mortality during the index presentation (17% vs 1.7%, P < .0001; hazard ratio 11.1; 95% confidence interval, 3.7-33.4) and at 2-year follow-up (47% vs 31%, P = .04; hazard ratio 1.92; 95% confidence interval, 1.17-3.14) than those with myocardial injury. Objective type 2 myocardial infarction had a higher mortality than subjective type 2 myocardial infarction at index presentation (17% vs 2.0%, P = .01) and at 1 (25% vs 9.1%, P = .04) and 3 months (31% vs 13%, P = .04) follow-up. There were no mortality differences between subjective type 2 myocardial infarction and myocardial injury.ConclusionIn patients diagnosed with type 2 myocardial infarction, those with objective evidence of myocardial ischemia have significantly worse outcomes compared with those with myocardial injury and subjective type 2 myocardial infarction. A more rigorous type 2 myocardial infarction definition that emphasizes these criteria may facilitate diagnosis and risk-stratification.Copyright © 2023 Elsevier Inc. All rights reserved.

17 keywords...

hide…