The prognostic value of the admission and predischarge electrocardiogram in acute coronary syndromes: the GUSTO-IIb ECG Core Laboratory experience.
BACKGROUND
Prior research suggests that patients may be entered into clinical trials with different electrocardiographic (ECG) findings than specified by study protocol criteria; the extent and impact of this variability in a large-scale trial have not been previously described.


METHODS
We evaluated the relationship between case report form (CRF) categorization of the admission ECG and a Core Laboratory and subsequent outcome in a retrospective analysis of a trial of patients with acute ischemia and a broad spectrum of ECG changes (the GUSTO-IIb trial).


RESULTS
In 11,037 patients with CRF information and an interpretable ECG, there was agreement in 89.1% of ST-elevation and 81.9% of non-ST-elevation cases. Among patients designated as having no ST elevation on the CRF, 1-year mortality rates were significantly higher in the subgroup of patients with Core Laboratory-determined ST elevation as compared with those where both the CRF and Core Laboratory classification were in agreement (8.8% vs 6.8%, P = .0093). Among patients designated as having ST elevation by the CRF, 1-year mortality rates were similar in both the subgroup of patients with and without Core Laboratory agreement (7.7% vs 8.2%, P = .72).


CONCLUSIONS
These findings have important implications for clinicians in routine practice because even a simple evaluation (presence or absence of ST elevation) on the admission ECG was often discordant and was associated with adverse clinical outcome.
Goodman
Shaun G
SG
The Canadian Heart Research Centre, Division of Cardiology, St. Michael's Hospital, University of Toronto, Toronto, Canada. goodmans@smh.toronto.on.ca
Fu
Yuling
Y
Langer
Anatoly
A
Barr
Aiala
A
Tan
Mary
M
Wagner
Galen S
GS
Barbagelata
Alejandro
A
Sgarbossa
Elena B
EB
Birnbaum
Yochai
Y
Granger
Christopher B
CB
Califf
Robert M
RM
Van de Werf
Frans
F
Topol
Eric J
EJ
Armstrong
Paul W
PW
D000368:Aged; D000789:Angina, Unstable / Q000401:mortality*; D004562:Electrocardiography; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000401:mortality*; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D013577:Syndrome