Incidence and outcomes of perioperative myocardial infarction/injury diagnosed by high-sensitivity cardiac troponin I

BACKGROUND: Perioperative myocardial infarction/injury (PMI) diagnosed by high-sensitivity troponin (hs-cTn) T is frequent and a prognostically important complication of non-cardiac surgery. We aimed to evaluate the incidence and outcome of PMI diagnosed using hs-cTnI, and compare it to PMI diagnosed using hs-cTnT.

METHODS: We prospectively included 2455 patients at high cardiovascular risk undergoing 3111 non-cardiac surgeries, for whom hs-cTnI and hs-cTnT concentrations were measured before surgery and on postoperative days 1 and 2. PMI was defined as a composite of perioperative myocardial infarction (PMIInfarct) and perioperative myocardial injury (PMIInjury), according to the Fourth Universal Definition of Myocardial Infarction. All-cause mortality was the primary endpoint.

RESULTS: Using hs-cTnI, the incidence of overall PMI was 9% (95% confidence interval [CI] 8-10%), including PMIInfarct 2.6% (95% CI 2.0-3.2) and PMIInjury 6.1% (95% CI 5.3-6.9%), which was lower versus using hs-cTnT: overall PMI 15% (95% CI 14-16%), PMIInfarct 3.7% (95% CI 3.0-4.4) and PMIInjury 11.3% (95% CI 10.2-12.4%). All-cause mortality occurred in 52 (2%) patients within 30 days and 217 (9%) within 1 year. Using hs-cTnI, both PMIInfarct and PMIInjury were independent predictors of 30-day all-cause mortality (adjusted hazard ratio [aHR] 2.5 [95% CI 1.1-6.0], and aHR 2.8 [95% CI 1.4-5.5], respectively) and, 1-year all-cause mortality (aHR 2.0 [95% CI 1.2-3.3], and aHR 1.8 [95% CI 1.2-2.7], respectively). Overall, the prognostic impact of PMI diagnosed by hs-cTnI was comparable to the prognostic impact of PMI using hs-cTnT.

CONCLUSIONS: Using hs-cTnI, PMI is less common versus using hs-cTnT. Using hs-cTnI, both PMIInfarct and PMIInjury remain independent predictors of 30-day and 1-year mortality.