Hf. Tse et al., Failure of coronary sinus pacing in reducing local atrial conduction delayin patients with atrial fibrillation after successful internal cardioversion, PACE, 23(6), 2000, pp. 1014-1019
Citations number
18
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Recent studies suggested that distal coronary sinus (CS) pacing may prevent
atrial fibrillation (AF) by reducing site dependent intraatrial conduction
delay. The aim of this study was to investigate the effect of high right a
trial (HRA) and distal CS pacing on local conduction delay in patients with
AF. The study population consisted of 10 patients crith persistent AF afte
r transvenous atrial defibrillation and 10 control subjects. The local cond
uction delays along the anterolateral right atrium (RA), in the CS, and at
the right atrial septum (RAS), and the incidence of AF in response to an at
rial extrastimulus during HRA and distal CS pacing at a drive cycle length
of 400, 500, and 600 ms were evaluated. In patients with AF, distal CS and
HRA pacing are associated with more prominent and similar extent of conduct
ion delay within the atria, without any significant difference in the dispe
rsion of conduction delay and susceptibility to AF induction (70% vs 60%, P
= 0.9). In normal controls, distal CS pacing reduces the conduction delay
at the RAS and CS ostium and decreases the dispersion of conduction delay a
nd the propensity for AF induction (0% vs 50%, P = 0.03) compared to HRA pa
cing. The pacing drive cycle length has no significant effect on conduction
delay in patients with AF and normal controls (P > 0.05). Compared to norm
al controls, patients with AF have significantly longer conduction delay at
the RAS and along the anterolateral RA during HRA and distal CS pacing. Th
e result of this study demonstrates that the effect of HRA and distal CS pa
cing on the local atrial conduction delay in patients with and without AF d
iffer significantly. These patients with AF may have more diffuse atrial an
isotropy causing the changes in conduction, and pacing from distal CS in th
ese patients dose not reduce the propensity for AF.