Dissimilar atrial rhythms. A patient with triple right atrial rhythm

A patient with complete A-V block and atrial fibrillation was analyzed by multiple intra-atrial electrograms. Three areas were recorded in the right atrium, each of them with different electrophysiological properties: (1) persistent atrial standstill, (2) irregular atrial activity with a rate of 50/minute, and (3) fibrilloflutter waves with a rate of 450/minute. The latter were also registered in the left atrium. This case illustrates another form of dissimilar atrial rhythms, and provides additional evidence of the importance of recording multiple electrograms from each atrium in the evaluation of the atrial events in atypical atrial arrhythmias.