title: Electrophysiological and anatomical differences of the slow pathway between the fast-slow form and slow-slow form of atrioventricular nodal reentrant tachycardia.
abstract: OBJECTIVE
  This study aimed to clarify whether electrophysiological and anatomical properties of the slow pathway (SP) could be different between the fast-slow form (F/S) and the slow-slow form (S/S) atrioventricular nodal reentrant tachycardia (AVNRT).
  
  
  RESULTS
  Nine patients with F/S and 15 patients with S/S of atypical AVNRT were studied. The patients with S/S were divided into two groups; those with the anterograde SP being eliminated (S/S aSP-E) or preserved (S/S aSP-P) during catheter ablation. HA (CS-His) was determined as the difference of the shortest HA interval between the His bundle region and the coronary sinus (CS) region. The ratio of the amplitudes of atrial and ventricular potential (A/V ratio) of the successful ablation site of the SP was also evaluated. Effective refractory period of the retrograde SP was shorter and HA intervals during both tachycardia and ventricular pacing were longer in F/S than in S/S. HA (CS-His) did not differ between F/S and S/S (-4.3 ± 20.2 vs.-4.4 ± 18.4 ms, NS). The A/V ratio was significantly greater in the S/S aSP-P group compared with the both groups of F/S and S/S aSP-E (0.83 ± 0.29 vs. 0.38 ± 0.09 and 0.26 ± 0.15 ms, P < 0.01).
  
  
  CONCLUSIONS
  Properties of the retrograde SP differ between F/S and S/S of AVNRT. Fast-slow form may utilize the same pathway for the retrograde conduction as the anterograde SP in S/S.
authors: Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors: Yosuke
authors: Y
authors: Nakatani
authors: Koichi
authors: K
authors: Mizumaki
authors: Kunihiro
authors: K
authors: Nishida
authors: Tamotsu
authors: T
authors: Sakamoto
authors: Yoshiaki
authors: Y
authors: Yamaguchi
authors: Naoya
authors: N
authors: Kataoka
authors: Masao
authors: M
authors: Sakabe
authors: Akira
authors: A
authors: Fujiki
authors: Hiroshi
authors: H
authors: Inoue
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D001283:Atrioventricular Node / Q000503:physiopathology* / Q000601:surgery; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome
keywords: Atrioventricular nodal reentrant tachycardia; Catheter ablation; Electrophysiology; Intermediate pathway; Reentrant circuit; Slow pathway