idioventricular rhythm
[ˌidiəuvenˈtrikjulə ˈriðəm]
Normally, the pacemaker of the heart that is responsible for triggering each heart beat (ventricular contraction) is the SA (Sino Atrial) node. However, if the ventricle does not receive triggering signals at a rate high enough, the ventricular myocardium itself becomes the pacemaker (escape rhythm).