Adenosine in the noninvasive diagnosis of dual AV nodal conduction: use as a follow-up parameter after slow pathway ablation in AVNRT.
OBJECTIVE
The aim of this study was to evaluate if administration of adenosine during sinus rhythm to patients with PSVT of unknown mechanism is capable to detect dual AV nodal conduction and furthermore to evaluate this diagnostic parameter as a controlling test after slow pathway ablation in AVNRT.


RESULTS
Before electrophysiological study 35 consecutive patients with PSVT were given adenosine during sinus rhythm. After radiofrequency ablation the adenosine test was repeated in a subset of 19 patients. The electrophysiological study revealed 19 patients (54%) with typical AVNRT (study group), 10 (29%) with atrioventricular reentry tachycardia (AVRT), 4 (11%) with ectopic atrial tachycardia (EAT) and 2 patients (6%) with inducible atrial flutter (AF) (control group). We observed a sudden increment of the PQ interval of more than 50 msec between two consecutive beats in 15 of 19 patients (79%) in the study group (75+/-35 msec) and in 2 patients (1 with EAT, AF) of the control group (19+/-12 msec) (p<0.001). After slow pathway radiofrequency ablation the sudden increment of PQ interval persisted in 4 of 12 patients (33%) of the study group. Three of these 4 patients had a relapse of AVNRT during a follow-up of 3 months.


CONCLUSIONS
The administration of adenosine during sinus rhythm is an excellent noninvasive diagnostic test for identifying dual AV nodal conduction and additionally for verifying radiofrequency ablation results in patients with AVNRT.
Dierkes
S
S
Department of Cardiology, Pneumology and Angiology, Heinrich Heine-University, Düsseldorf, Germany.
Vester
E G
EG
Dobran
L J
LJ
Perings
C
C
Strauer
B E
BE
D000241:Adenosine; D000293:Adolescent; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents; D001283:Atrioventricular Node / Q000503:physiopathology*; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery
D000889:Anti-Arrhythmia Agents; D000241:Adenosine