Accelerated idioventricular rhythm (AIVR) is a ventricular rhythm occuring at a rate between 41-100 / minute - faster than typical pacemaker rates expected of the ventricles (20-40 / minute) and less than what is considered a tachycardia (>100 / minute). Enhanced automaticity - possibly due to hypoxia or abundant sympathetic stimulation - increases rate of ventricular electrical impulses. Note that this rhythm is often unstable and can move quickly to either asystole or ventricular tachycardia (VT).
The causes of this are myocardial ischemia, electrolyte imbalance, and a heartbeat of more than 100 beats per minute.
No treatment is needed without heart problems.
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