TIME TO POSITIVITY OF A RAPID BEDSIDE ASSAY FOR CARDIAC-SPECIFIC TROPONIN-T PREDICTS PROGNOSIS IN ACUTE CORONARY SYNDROMES - A THROMBOLYSISIN MYOCARDIAL-INFARCTION (TIMI) 11A SUBSTUDY
Em. Antman et al., TIME TO POSITIVITY OF A RAPID BEDSIDE ASSAY FOR CARDIAC-SPECIFIC TROPONIN-T PREDICTS PROGNOSIS IN ACUTE CORONARY SYNDROMES - A THROMBOLYSISIN MYOCARDIAL-INFARCTION (TIMI) 11A SUBSTUDY, Journal of the American College of Cardiology, 31(2), 1998, pp. 326-330
Objectives. We sought to determine whether the rapid bedside assay for
troponin T identified patients at risk for a more complicated hospita
l stay and a higher rate of adverse clinical events. Background. In pa
tients with an acute coronary syndrome, the amount of cardiac-specific
troponin T released bears a stoichiometric relation to the extent of
myocardial damage. Methods. In 597 patients, with unstable angina or n
on-Q wave myocardial infarction participating in the Thrombolysis in M
yocardial Infarction (TIMI) 11A substudy, a rapid bedside assay and si
multaneous quantitative serum measurement for troponin T were obtained
at enrollment. Results. The composite end point of the sum of death,
nonfatal myocardial infarction or recurrent ischemia through day 14 oc
curred in 33.6% of patients with a positive assay compared with only 2
2.5% of patients with a negative assay (p = 0.01), Those patients in w
hom the rapid assay became positive in less than or equal to 10 min ha
d the highest mortality rate of 4.2% through day 14 compared with 1.1%
in those patients who had either a late-appearing positive assay (>10
min) or a negative assay. The duration of hospital stay in the 116 pa
tients (19%) with a positive rapid assay at enrollment was a median of
5 days compared with only 3 days in the 481 patients (81%) with a neg
ative rapid assay at enrollment (p = 0.002). Conclusions. A positive r
apid assay for troponin T at presentation identifies those patients at
risk for higher rates of adverse clinical events and longer, more com
plicated hospital stays, Stratification of patients by time to develop
ment of a positive rapid assay identifies those patients at highest mo
rtality risk (C) 1998 by the American College of Cardiology.