Premium
Quantitative Analysis of Concealed Conduction into Accessory Atrioventricular Pathways in Wolff‐Parkinson‐White Syndrome
Author(s) -
TANAKA KAZUSHI,
SUZUKI FUMIO,
HIEJIMA KAZUMASA,
FUJIMURA OSAMU
Publication year - 1997
Publication title -
pacing and clinical electrophysiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.686
H-Index - 101
eISSN - 1540-8159
pISSN - 0147-8389
DOI - 10.1111/j.1540-8159.1997.tb06789.x
Subject(s) - medicine , accessory pathway , thermal conduction , anesthesia , cardiology , electrophysiology , electrical conduction system of the heart , anatomy , neuroscience , electrocardiography , psychology , catheter ablation , atrial fibrillation , physics , thermodynamics
Concealed conduction is demonstrated to occur in an accessory AV pathway (AP). To test the hypothesis that anterograde and retrograde concealed conduction in the AP would have different characteristics, 35 consecutive patients with single APs were studied. The anterograde or retrograde ERP of the AP could be determined in 23 of those patients. Anterograde concealed conduction in the AP was assessed in the first 13 patients with retrograde AP conduction (8 APs with retrograde conduction only and 5 with both directions) (group A). Retrograde concealed conduction in the AP was evaluated in the remaining 10 patients with anterograde AP conduction (6 APs with anterograde conduction only and 4 with both directions) (group B). The concealed conduction in the AP was quantified by determining the ERP of the AP using a “probe” extrastimulus (S p ) introduced in the opposite chamber. The ERP was determined both during conventional extrastimulus (S 1 S 2 method; ERP c ) and during that with an S p (S 1 S p S 2 method; ERP p ). The S p was delivered before or after the last S 1 with various S 1 S p intervals. The ERP p was determined at each S 1 S p interval. Three distinct patterns in concealed conduction in the AP were noted. In the first pattern, the ERP p was always shorter than the ERP c , whereas the reverse relation was noted in the second pattern. The third pattern showed a combination of the two. In group A, only the first pattern was noted. In group B, the first, second, and third patterns were noted in 4, 2, and 4 patients, respectively. The first pattern was noted only in septal APs and the second and third were seen only in left free‐wall APs. The second pattern was seen in patients with retrograde AP conduction, whereas the third one was mainly noted in patients without retrograde AP conduction. These observations indicate that anterograde and retrograde concealed conduction in the AP have different characteristics. Shortening of the ERP p might be due to the “peeling back” phenomenon, and its lengthening might be caused by the presence of the inhomogeneous refractory periods of the AP. (PACE 1997; 20[Pt. I]:1342‐1353)