Atrioventricular node reentrant tachycardia in patients with a long fast pathway effective refractory period: clinical features, electrophysiologic characteristics, and results of radiofrequency ablation.
Twenty-two patients (group 1) with AV node reentrant tachycardia and a baseline fast pathway effective refractory period (ERP) > or = 500 msec were compared with 30 consecutive patients (group 2) with AV node reentrant tachycardia and a fast pathway ERP < 500 msec. Both groups underwent slow pathway ablation. In the patients with complete elimination of slow pathway, the fast pathway ERP and shortest 1:1 conduction cycle length shortened significantly after ablation but was greater in group 1 (n = 14) than in group 2 (n = 21) (125 +/- 78 msec vs 48 +/- 29 msec, p < 0.001 and 103 +/- 72 msec vs 52 +/- 30 msec, p < 0.001, respectively). In group 1, the shortening of fast pathway ERP was correlated to baseline difference between anterograde fast and anterograde slow ERP (r = 0.806, p < 0.001, slope = 1.08), and the shortening of fast pathway shortest 1:1 conduction cycle length was correlated to baseline difference between anterograde fast and anterograde slow shortest 1:1 conduction cycle length (r = 0.885, p < 0.001, slope = 1.47). During follow-up bradycardia did not develop in any patient and no one required pacing. This shortening of the fast pathway ERP and shortest 1:1 conduction cycle length after complete elimination of slow pathway reduced the concern of subsequent impairment of AV node conduction.
Lee
S H
SH
Division of Cardiology, National Yang-Ming University, Veterans General Hospital, Taipei, Taiwan, Republic of China.
Chen
S A
SA
Tai
C T
CT
Chiang
C E
CE
Wen
Z C
ZC
Chen
Y J
YJ
Yu
W C
WC
Fong
A N
AN
Huang
J L
JL
Cheng
J J
JJ
Chang
M S
MS
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000328:Adult; D000368:Aged; D017115:Catheter Ablation; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects / Q000503:physiopathology*; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology* / Q000601:surgery
D000318:Adrenergic beta-Agonists; D007545:Isoproterenol