Polarity of the ST Vector

Abstract

A technique has been evolved which yields consistently reproducible electrocardiographic records of injury effects in the dog as a result of the application of potassium chloride to the epicardium. The electrical results were recorded both by a string galvanometer and a condenser coupled amplifier electrocardiographic apparatus. The electrocardiograms taken by the two machines were different. Injury to the anterior wall of the dog's heart results solely in a depression of the baseline, the TP and PR interval segments. The ST segment ‘take off’ remains at the isoelectric level.