Studies of Electrocardiographic Changes during Exercise (Modified Double Two-Step Test)

Abstract

A method of recording electrocardiograms during the performance of a double two-step exercise test is described. Data obtained from 32 normal subjects and 54 patients are analyzed, and changes in heart rate, S-T segment, T wave and Q-T interval and the occurrence of premature beats described. Criteria for an abnormal response indicating coronary insufficiency are defined. This method retains the merits of Master's original test and in addition has several distinct advantages.