The QRS complex can be wide if aberrancy is present (ie, right or left bundle branch blocks). Causes of atrial tachycardia include chronic hypertension, congestive heart failure, valvular heart ...

The three irregularly irregular rhythms are atrial fibrillation, atrial flutter with variable conduction and multifocal atrial tachycardia (similar to wandering atrial pacemaker). Atrioventricular ...