What is a common heart rate associated with idioventricular rhythm?

Idioventricular rhythm is characterized by a heart rate that typically falls within a range of 20 to 40 beats per minute. This rhythm arises when the higher pacemakers of the heart, such as the sinoatrial (SA) node and atrioventricular (AV) node, fail to function properly. As a result, the ventricles take over as the primary pacemaker, which leads to this slower heart rate.

The idioventricular rhythm is often seen as a protective mechanism during instances where there is a failure of higher-level cardiac impulses, such as in cases of complete heart block or significant myocardial infarction. This is why the correct answer identifies a heart rate of 40 bpm or less as typical for idioventricular rhythm, highlighting the lower range that characterizes this condition.