Ischemic Polareardiographic Changes Induced By Exercise A New Criterion

The polarcardiographic responses to exercise in normal men, young and middle-aged, have been compared with those of men who show ischemic responses on the electrocardiogram. Changes in the ST-vectors are the most significant. These changes have been reduced to a single numerical quantity based on the spatial magnitude of the vector at the end of the QRS complex and the spatial direction of a vector occurring at a clearly specified time during the period of the ST-segment. The assets of polarcardiography are that it enables study of direction and nwgnitude of ST-vectors in a time sequence. Thus it provides information of clinical importance which cannot be obtained by either electroor vectorcardiography.