Comparison between scalar and corrected orthogonal electrocardiogram in diagnosis of acute myocardial infarcts.

Twelve-lead electrocardiograms and orthogonal electrocardiograms taken with Frank's corrected orthogonal lead system have been compared in 259 patients with recent myocardial infarction. In the scalar electrocardiograms a diagnostic recognition rate of 62 per cent was recorded. QIRratios > 0O2I in X lead, > o 22 in Y lead, and I -20 in Z lead were used as signs of myocardial infarction in the orthogonal electrocardiograms. Eighty-two per cent showed pathological QIR ratios according to these criteria. The orthogonal electrocardiogram technique is of value in the diagnosis of recent myocardial infarction because of its simplicity, the strict criteria which can be applied, and the high recognition rate.