Catheter Mapping and Ablation of Right Atrial Tachycardias

Objective To investigate the methods of mapping and ablation of right atrial tachycardia. Methods Three cases of right atrial tachycardia were confirmed by routine electrophysilogic examination. Multipolar mapping catheter was curved and rotated in the right atrium to map the atrial wall for exploring the site of relative early atrial electrogram preceded the P wave in the surface electrocardiogram. Ablative catheter was used to map carefully near this site through Swartz sheath to locate the earliest site of atrial activation where radiofrequency energy was delivered. The energy was titrated from 15 W to 25 W. Results Ablation was successful in all three patients. The local atrial electrograme preceded the onset of the P wave by 40～50 ms at the successful ablation site. The atrial tachycardias were terminated by using 15 W of power for less than 5 s. Successful ablation in the three patients required 2～4 radiofrequcency energy applications and 28～36 min fluoroscopy time. Conclusion It is simple and effective that radiofrequency ablation of right atrial tachycardia was guided by general mapping of multipolar catheter and careful mapping of ablative catheter through Swartz sheath to locate the site of earliest atrial activation.