Spontaneous gap phenomenon in atrioventricular conduction produced by His bundle extrasystoles

A gap in atrioventricular conduction is a zone within the cardiac cycle during which premature impulses are blocked in the conduction system, while impulses of greater or lesser prematurity are conducted. This has previously been produced only by atrial or ventricular stimulation techniques. This report demonstrates a spontaneous gap produced by His extrasystoles.