Elevated cardiac troponin levels predict the risk of adverse outcome in patients with acute coronary syndromes.
BACKGROUND
Elevations of cardiac troponin T or I are predictive of adverse outcomes in patients with acute coronary syndromes. However, odds ratios (ORs) vary substantially between studies. This investigation refines these values by means of a meta-analysis.


METHODS
Twenty-one studies were suitable. ORs were calculated for short-term (30 days) and long-term (5 months to 3 years) follow-up in patients with ST-segment elevation (ST upward arrow), in those without ST-segment elevation (no ST upward arrow), and in patients with unstable angina. The primary end point was a composite of death or nonfatal myocardial infarction.


RESULTS
A total of 18,982 patients were included. At 30 days, the OR for death or myocardial infarction was 3.44 (95% confidence interval [CI], 2.94-4.03; P <. 00001) for patients with positive troponin. In the ST upward arrow group, troponin elevations carried a 2.86-fold (95% CI, 2.35-3.47; P <.0001) higher risk during short-term follow-up, which was maintained long term. The no-ST upward arrow patients with troponin elevations manifested a 4.93-fold (95% CI, 3.77-6.45; P <.0001) increase of adverse outcomes. The OR for patients with unstable angina and positive troponin was 9.39 (95% CI, 6.46-13.67; P <.0001). For cardiac death alone, the results were similar.


CONCLUSIONS
Patients with acute coronary syndromes who have troponin elevations show a substantial increase in risk during short and long-term follow-up.
Ottani
F
F
M.Z. Sacco Heart Foundation; the Cardiology Division, Bentivoglio Hospital, Bentivoglio, Forlì, Italy. ottanif@amf.dsnet.it
Galvani
M
M
Nicolini
F A
FA
Ferrini
D
D
Pozzati
A
A
Di Pasquale
G
G
Jaffe
A S
AS
D000789:Angina, Unstable / Q000097:blood* / Q000401:mortality / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D016757:Death, Sudden, Cardiac; D006801:Humans; D009203:Myocardial Infarction / Q000097:blood* / Q000401:mortality / Q000503:physiopathology; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D012720:Severity of Illness Index; D015996:Survival Rate; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T