Summary: Accelerated Idioventricular Rhythm, wide QRS supraventricular tachycardia vs ventricular tachycardia, adenosine, causes of wide QRS SVT, antidromic and orthodromic atrioventricular reentrant tachycardia (AVRT), atrial flutter, preexcitation syndrome, WPW, LGL, Mahaim fibers