OBJECTIVETo analyze the characteristics of atrial tachycardia originating from the atrioventricular cingulum.

METHODThe electrophysiological mechanism, ablation site graph and nerve distribution of 16 cases of atrial tachycardia originating from the atrioventricular cingulum or adjacent atrial muscle which were proved by electrophysiological monitoring and radiofrequency ablation.

RESULTSAtrial tachycardia from peri-cingulum represented 23.2% of atrial tachycardia treated by radiofrequency ablation during the same period. The ratio of left to right atrioventricular cingulum was 3:16. There was no difference of the surface ECG characteristics and electrophysiological mechanism between the atrial tachycardia originating from atrioventricular cingulum and that from other positions. Both A and V components were recorded at all the successful ablation sites. The ratio of amplitude of A to V was between 2:3 and 6:1. Atrial potential in the target site was 20-46 (38.6 +/- 6.7) ms earlier than P'wave in surface ECG. The success rate of ablation was 87.5% and the recurrent rate 7.1%.

CONCLUSIONSPeri-cingulum atrial tachycardia accounts for a certain proportion in all atrial tachycardia. The exciting sites originating from right cingulum are more common than those from left cingulum. Its electrophysiological mechanism has no difference from other positions. Cingulum mapping and ablation have important practical meanings.