Electrocardiographic changes subsequent to artificial ventricular depolarization.

Massive T wave inversion and ST depression occur in the unpaced electrocardiogram subsequent to ventricular pacing, and persist for a varying length of time depending on the duration of pacing. That artificial depolarization of the ventricle causes chan- ges in repolarization which persist after stopping pacing is of considerable theoretical and practical importance, and we describe the findings in 31 patients both with and without disease of the conduction tissue.