This document discusses junctional rhythms, which occur when the atrioventricular (AV) node acts as the backup pacemaker when the sinoatrial (SA) node fails. There are three types of junctional rhythm: junctional rhythm with a rate of 40-60 bpm; accelerated junctional rhythm with a rate of 61-100 bpm; and junctional tachycardia with a rate of 101-180 bpm. All junctional rhythms lack P waves or have inverted, buried, or retrograde P waves and a absent, short, or retrograde PR interval. Causes include SA node disease, increased vagal tone, digitalis use, and inferior wall myocardial infarction. Treatment options are