The etiology and prognostic significance of cardiac troponin I elevation in unselected emergency department patients.
BACKGROUND
Cardiac troponin elevations are associated not only with acute coronary syndromes (ACS) but also with multiple other cardiac and non-cardiac conditions.


OBJECTIVE
To investigate the etiology and clinical significance of cardiac troponin I elevations in an unselected Emergency Department (ED) patient cohort.


METHODS
The study population consisted of 991 consecutive troponin-positive patients admitted to the ED of a university hospital with ACS as the presumptive diagnosis. Cardiac troponin I was measured on admission and a follow-up sample was obtained at 6-12 h. Clinical diagnosis was ascertained retrospectively using all the available information including electrocardiogram, clinical data, laboratory tests, and available coronary angiograms.


RESULTS
At admission, 805 (81.2%) patients were already troponin positive; of these, the troponin elevation was related to myocardial infarction (MI) in 654 (81.2%) patients. Finally, 83.0% of the troponin elevations were due to MI, 7.9% were related to other cardiac causes, and 9.1% to non-cardiac diseases. The leading non-cardiac causes were pulmonary embolism, renal failure, pneumonia, and sepsis. Non-cardiac patients with elevated troponin I at admission showed significantly higher in-hospital mortality (26.7% vs. 13.4%, p = 0.002) compared to cardiac patients.


CONCLUSIONS
Elevated troponin levels for reasons other than MI are common in the ED and are a marker of poor in-hospital prognosis.
Ilva
Tuomo J
TJ
Department of Internal Medicine, Kanta-Hame Central Hospital, Hameenlinna, Finland.
Eskola
Markku J
MJ
Nikus
Kjell C
KC
Voipio-Pulkki
Liisa-Maria
LM
Lund
Juha
J
Pulkki
Kari
K
Mustonen
Harri
H
Niemelä
Kari O
KO
Karhunen
Pekka J
PJ
Porela
Pekka
P
D000368:Aged; D015415:Biomarkers / Q000097:blood; D004630:Emergencies; D005260:Female; D005387:Finland / Q000453:epidemiology; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis; D011379:Prognosis; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I