Ablation of atrial tachycardia originating from the noncoronary sinus: case report and literature review.

This report describes a patient with atrial tachycardia who underwent radiofrequency catheter ablation. Two applications of radiofrequency energy were received at different sites within 1 week. Initially, right atrium mapping indicated that the earliest activation site was located at the His-bundle region (HBR). However, the first application of radiofrequency near HBR appeared to be ineffective. Moreover, a degree III atrioventricular block and inferior ST-segment elevation was temporally observed during the therapy, which recovered after drug treatment. As later aortic sinus mapping showed that the activation site located at the noncoronary sinus (NCS) preceded the one at HBR, and this activation terminated at atrial tachycardia, a second application of radiofrequency was performed at NCS without any complications. In addition, a literature review of the clinical features of atrial tachycardia at the NCS is also summarized in the present report.