Inter-Rater Reliability of ST-Segment Measurement at a University Hospital in Argentina

The accurate determination of the electrocardiographic ST-segment elevation in a patient with clinical suspicion of acute coronary syndrome is essential for treatment with urgent myocardial reperfusion. The aim of this study was to determine the inter-rater reliability of ischemic and non-ischemic ST-segment elevation measurement among physicians with different specialties and experience. We performed an observational, cross-sectional study, with a comparative correlation and paired sampling. 56 physicians from a university hospital in Buenos Aires city were included: Cardiologists from the Coronary Care Unit (CCU) and Cardiology Division, Internal Medicine physicians from the hospitalization, ambulatory care and Emergency divisions, and third- and fourth-year Internal Medicine residents. Each participant analyzed 6 electrocardiograms and was asked to determine the magnitude of the ST-segment elevation at the J-point, and the corresponding diagnosis. The inter-rater coefficient was lower than 0.2, and the global kappa coefficient was 0.06 (p < 0.001). The global correct interpretations were: inferior wall myocardial infarction (MI): 89.3%; anterior wall MI: 51.8%; lateral wall MI: 75%; left bundle branch block: 91.1%; left ventricle hypertrophy: 44.6%; acute pericarditis: 25%. We believe that the low correlation was probably due to the difficulty in determining the J-point. These findings could suggest the need to strengthen the electrocardiographic concepts of ischemia, and the differentiation between ischemic and non-ischemic ST-segment elevations.