An assessment of ST-segment measurement variability between two core electrocardiogram laboratories.
OBJECTIVE
We evaluated inter-reader agreement of the ST-segment between two electrocardiogram (ECG) core laboratories.


BACKGROUND
Accurate measurement of the ST-segment is key to diagnosis and management of acute coronary syndromes (ACS). Clinical trials also rely on adherence to the pre-specified ECG eligibility criteria.


METHODS
150 patients (100 ST-segment elevation (STE)-ACS, 50 non-STE-ACS) were selected. An experienced ECG reader from each laboratory measured ST-segment deviation on the baseline ECGs (nearest 0.1mm).


RESULTS
∑ST-segment deviation showed excellent inter-reader agreement (R=0.965, intraclass correlation coefficient (ICC) 0.949, 95% CI (0.930-0.963)). Similar agreement was observed when ∑ST-segment elevation (∑STE) and ∑ST-segment depression (∑STD) were assessed separately. Better agreement was evident in STE-ACS cohort (ICC (95% CI): 0.968 (0.953-0.978, 0.969 (0.954-0.979), 0.931 (0.899-0.953)) compared to NSTE-ACS patients (ICC (95% CI): 0.860 (0.768-0.917), 0.816 (0.699-0.890), 0.753 (0.605-0.851) across measurement of ∑ST-segment deviation, ∑STE, and ∑STD.


CONCLUSIONS
We demonstrated excellent agreement on ST-segment measurements between two experienced readers from two ECG core laboratories.
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Neda
N
Dianati Maleki
Saint Louis University Health Sciences Center, St Louis, MO, USA.
Karen
K
Stocke
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Yinggan
Y
Zheng
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Cynthia M
CM
Westerhout
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Yuling
Y
Fu
Saint Louis University Health Sciences Center, St Louis, MO, USA.
Bernard R
BR
Chaitman
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Ahmed
A
Awad
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada.
Pushpa
P
Jagasia
Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada. Electronic address: paul.armstrong@ualberta.ca.
Paul W
PW
Armstrong
D000368:Aged; D000416:Alberta; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007755:Laboratories, Hospital / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D008923:Missouri; D009203:Myocardial Infarction / Q000175:diagnosis*; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
Acute coronary syndromes; Electrocardiogram; Reliability