
Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Accelerated idioventricular rhythm differential diagnosis
Introduction
Overview
Overview
AIVR must be distinguished from normal sinus rhythm, junctional tachycardia, and slow VT.
Normal Sinus Rhythm
Normal Sinus Rhythm
Because of its slower rate, AIVR may resemble normal sinus rhythm (NSR). AIVR is disnguished by the presence of numerous fusion beats to distinguish it from NSR. Given the difficulty in distinguishing these rhythms, the term accelerated isorhythmic ventricular rhythm has been suggested.
Junctional Tachycardia
Junctional Tachycardia
AIVR should also be distinguished from junctional tachycardia with preexisting intraventricular conduction delays (IVCD)s. In patients with junctional tachycardia, there are no fusion beats or capture beats.
Slow Ventricular Tachycardia
Slow Ventricular Tachycardia
In general, the rate of AIVR is slower (<100-120 bpm) than ventricular tachycardia (at least 100-120 bpm). There can, however, be overlap in the rate associated with AIVR and slow VT. The distinction is critical as misdiagnosis as slow VT can results in inappropriate therapy such as cardioversion and anti-arrhythmic administration.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
