Atrial flutter is a form of cardiac arrhythmia characterized by an atrial rate ranging from 240 to 400 beats per minute.  It is the most common atrial tachycardia after atrial fibrillation, with a uniform and regular continuous wave-form.  It is caused by a reentrant rhythm in either the right or left atrium.  Some degree of atrio-ventricular block is usually associated with atrial flutter.  Similar to atrial fibrillation the rate of ventricular beating depends on the degree of conduction through the atrioventricular node.  The usual scenario is 2:1 or 4:1 conduction but occasionally there can exist a 1:1 conduction.
Atrial flutter pathophysiology
AVNRT laboratory findings
Sinoatrial arrest pathophysiology
AVNRT risk factors
Pulseless ventricular tachycardia pathophysiology
AVNRT pathophysiology
Atrial flutter risk factors
Wide complex tachycardia epidemiology and demographics