TY - JOUR
T1 - Determinants of fast and slow pathway conduction in patients with dual atrioventricular nodal pathways
AU - Wu, D.
AU - Denes, P.
AU - Dhingra, R.
AU - Wyndham, C.
AU - Rosen, K. M.
PY - 1975
Y1 - 1975
N2 - Electrophysiologic studies were performed in two patients with documented paroxysmal supraventricular tachycardia and dual atrioventricular (AV) nodal pathways as defined by the atrial extra stimulus technique. Both patients manifested two ranges of A H intervals (AV nodal conduction times) at critical cycle lengths, reflecting fast and slow pathway conduction. The occurrence of fast and slow pathway conduction at the same cycle length depended on a long fast pathway effective refractory period relative to the spontaneous or driven cycle length. At critical cycle lengths with fast pathway conduction, a shift to slow pathway conduction could be induced by a premature atrial impulse falling within the effective refractory period of the fast pathway. Repetitive retrograde concealed conduction to the fast pathway, then maintained antegrade slow pathway conduction. Resumption of fast pathway conduction was induced with premature atrial impulses falling within the effective refractory periods of the fast and the slow pathways, allowing recovery of the fast pathway for antegrade conduction. Atrial echoes and AV nodal reentrant paroxysmal supraventricular tachycardia occurred when sufficient slow pathway delay was achieved to allow recovery of the fast pathway for retrograde conduction.
AB - Electrophysiologic studies were performed in two patients with documented paroxysmal supraventricular tachycardia and dual atrioventricular (AV) nodal pathways as defined by the atrial extra stimulus technique. Both patients manifested two ranges of A H intervals (AV nodal conduction times) at critical cycle lengths, reflecting fast and slow pathway conduction. The occurrence of fast and slow pathway conduction at the same cycle length depended on a long fast pathway effective refractory period relative to the spontaneous or driven cycle length. At critical cycle lengths with fast pathway conduction, a shift to slow pathway conduction could be induced by a premature atrial impulse falling within the effective refractory period of the fast pathway. Repetitive retrograde concealed conduction to the fast pathway, then maintained antegrade slow pathway conduction. Resumption of fast pathway conduction was induced with premature atrial impulses falling within the effective refractory periods of the fast and the slow pathways, allowing recovery of the fast pathway for antegrade conduction. Atrial echoes and AV nodal reentrant paroxysmal supraventricular tachycardia occurred when sufficient slow pathway delay was achieved to allow recovery of the fast pathway for retrograde conduction.
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U2 - 10.1161/01.RES.36.6.782
DO - 10.1161/01.RES.36.6.782
M3 - Article
C2 - 1132071
AN - SCOPUS:0016691902
VL - 36
SP - 782
EP - 790
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
SN - 0891-5849
IS - 6
ER -