Troponin elevation in patients without acute coronary syndrome

Introduction and objectives: Troponins are specific biomarkers of myocardial injury and are implicated in the diagnosis and prognosis of patients with acute coronary syndrome. Our purpose was to determine the clinical characteristics and prognosis of patients with troponin elevation who are not diagnosed with acute coronary syndrome.

Methods: A total of 1032 patients with an emergency room troponin measurement were studied retrospectively, dividing them into 3 groups: 681 patients with no troponin elevation and without acute coronary syndrome, 139 with acute coronary syndrome, and 212 with troponin elevation and not diagnosed with acute coronary syndrome. The clinical characteristics and in-hospital and 12-month mortality of these 3 groups were compared.

Results: Patients with troponin elevation not diagnosed with acute coronary syndrome were older and had greater comorbidity than patients with acute coronary syndrome or no troponin elevation. The 12-month mortality was 30.2%, compared with 15.1% and 4.7% in the other groups (log rank test, P<.001). In the Cox logistic regression model adjusted for confounding variables, patients with troponin elevation and no diagnosis of acute coronary syndrome had higher mortality compared with patients with negative troponin without acute coronary syndrome (hazard ratio=3.99; 95% confidence interval, 2.36-6.75; P<.001) and similar prognosis as patients with acute coronary syndrome.

Conclusions: Troponin elevation is an important predictor of mortality, regardless of the patient's final diagnosis.