Troponin level at presentation as a prognostic factor among patients presenting with non-ST-segment elevation myocardial infarction

Background: Timely reperfusion within 120 min is strongly recommended in patients presenting with non-ST-segment myocardial infarction (NSTEMI) with very high-risk features. Evidence regarding the use of high-sensitivity cardiac troponin (hs-cTn) concentration upon admission for the risk-stratification of patients presenting with NSTEMI to expedite percutaneous coronary intervention (PCI) and thus potentially improve outcomes is limited.

Methods: All patients admitted to a tertiary care center ICCU between July 2019 and July 2022 were included. Hs-cTnI levels on presentaion were recorded, dividing patients into quartiles based on baseline hs-cTnI. Association between initial hs-cTnI and all-cause mortality during up to 3 years of follow-up was studied.

Results: A total of 544 NSTEMI patients with a median age of 67 were included. Hs-cTnI levels in each quartile were: (a) ≤122, (b) 123-680, (c) 681-2877, and (d) ≥2878 ng/L. There was no difference between the initial hs-cTnI level groups regarding age and comorbidities. A higher mortality rate was observed in the highest hs-cTnI quartile as compared with the lowest hs-cTnI quartile (16.2% vs. 7.35%, p = .03) with hazard ratio (HR) for mortality of 2.6 (95% confidence interval [CI]: 1.23-5.4; p = .012) in the unadjusted model, and HR of 2.06 (95% CI: 1.01-4.79; p = .047) with adjustment for age, gender, serum creatinine, and significant comorbidities.

Conclusions: Patients with NSTEMI and higher hs-cTnI levels upon admission faced elevated mortality risk. This underscores the need for further prospective investigations into early reperfusion strategies' impact on NSTEMI patients' mortality, based on admission troponin elevation.