Complex atrial dysrhythmias in a patient with congestive cardiomyopathy

A patient with primary cardiomyopathy and long standing atrial fibrillation presented with atrial tachycardia and AV block. Atrial pacing sequentially converted the atrial tachycardia to atrial flutter (biatrial) and to the dissimilar atrial rhythms of right atrial fibrillation with left atrial flutter, right atrial flutter with left atrial electrical standstill and right atrial fibrillation with left atrial standstill. The clincial milieu and intracardiac recordings are presented.