Sensitive troponin I assay in early diagnosis of acute myocardial infarction.
BACKGROUND
Cardiac troponin testing is central to the diagnosis of acute myocardial infarction. We evaluated a sensitive troponin I assay for the early diagnosis and risk stratification of myocardial infarction.


METHODS
In a multicenter study, we determined levels of troponin I as assessed by a sensitive assay, troponin T, and traditional myocardial necrosis markers in 1818 consecutive patients with suspected acute myocardial infarction, on admission and 3 hours and 6 hours after admission.


RESULTS
For samples obtained on admission, the diagnostic accuracy was highest with the sensitive troponin I assay (area under the receiver-operating-characteristic curve [AUC], 0.96), as compared with the troponin T assay (AUC, 0.85) and traditional myocardial necrosis markers. With the use of the sensitive troponin I assay (cutoff value, 0.04 ng per milliliter) on admission, the clinical sensitivity was 90.7%, and the specificity was 90.2%. The diagnostic accuracy was virtually identical in baseline and serial samples, regardless of the time of chest-pain onset. In patients presenting within 3 hours after chest-pain onset, a single sensitive troponin I assay had a negative predictive value of 84.1% and a positive predictive value of 86.7%; these findings predicted a 30% rise in the troponin I level within 6 hours. A troponin I level of more than 0.04 ng per milliliter was independently associated with an increased risk of an adverse outcome at 30 days (hazard ratio, 1.96; 95% confidence interval, 1.27 to 3.05; P=0.003).


CONCLUSIONS
The use of a sensitive assay for troponin I improves early diagnosis of acute myocardial infarction and risk stratification, regardless of the time of chest-pain onset.
Keller
Till
T
Department of Medicine II, University Medical Center, Johannes Gutenberg University, Mainz, Germany.
Zeller
Tanja
T
Peetz
Dirk
D
Tzikas
Stergios
S
Roth
Alexander
A
Czyz
Ewa
E
Bickel
Christoph
C
Baldus
Stephan
S
Warnholtz
Ascan
A
Fröhlich
Meike
M
Sinning
Christoph R
CR
Eleftheriadis
Medea S
MS
Wild
Philipp S
PS
Schnabel
Renate B
RB
Lubos
Edith
E
Jachmann
Nicole
N
Genth-Zotz
Sabine
S
Post
Felix
F
Nicaud
Viviane
V
Tiret
Laurence
L
Lackner
Karl J
KJ
Münzel
Thomas F
TF
Blankenberg
Stefan
S
D000368:Aged; D000789:Angina, Unstable / Q000097:blood / Q000175:diagnosis; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000209:etiology; D015897:Comorbidity; D042241:Early Diagnosis; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood
D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T