Main-stem extrasystoles with aberrant ventricular conduction mimicking ventricular extrasystoles ∗

Abstract

This brief exposé stresses the fact that ventricular premature beats cannot be diagnosed with certainty and illustrates the reason by presenting, perhaps for the first time, main-stem extrasystoles with aberrant ventricular conduction recognizable as such only by means of new criteria. How many of the premature beats we glibly call ectopic ventricular are in reality supraventricular—arising in the A-V junctional tissues without retrograde conduction to the atria—we at present have no means of knowing. The justification for labeling such beats main-stem is briefly discussed.