[Radiofrequency transcatheter ablation of dual atrioventricular nodal reentrant tachycardia].
24 cases of dual atrioventricular nodal reentry tachycardia (DAVNRT) were identified by EPS. Radiofrequency transcatheter ablation (RFCA) was applied to interrupt the slow pathways (SP) conduction with a large tip catheter in all the cases. The records from the ablation catheter in the first 8 cases were analysed retrospectively; a low amplitude, relatively slow spike ("B" wave) was found in all the successful cases. In the following 16 cases, "B" waves were purposely sought for the site of ablation, which was usually on the middle and proximal third of the line between His bundle and coronary sinus OS. AB interval was measured, it ranged from 35 to 65 ms with an average of 29 ms, being shorter than the AH interval. "B" wave usually followed the "jump" from the fast to SP, and was not eliminated by RFCA. As compared with the original ablation method, less energy (22.8 vs 26.1 W, P < 0.01) and shorter time of X-ray exposure were needed, if the RF current was applied at "B" site. During the ablation, A wave should be much smaller than V wave, in order not to damage the AVN. The appearance of junctional rhythm usually indicates a successful ablation of SP, SP were eliminated in all the 24 cases. After a follow-up of more than 2 months, recurrence was found in one patient, who underwent a second ablation. Complete AV block occurred in 1 patient, who had a pacemaker implanted. The presence of "B" wave possibly indicates the existence of a short pathway between the fast and SP. RF current applied at that site was safe and more effective.
Wu
N
N
PUMC Hospital, Beijing.
Lan
Z Q
ZQ
Deng
H
H
D000293:Adolescent; D000328:Adult; D017115:Catheter Ablation; D004594:Electrophysiology; D005260:Female; D006321:Heart / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology / Q000601:surgery*