The acute effects of biatrial pacing on atrial depolarization and repolarization

Citation
Dm. Gilligan et al., The acute effects of biatrial pacing on atrial depolarization and repolarization, PACE, 23(7), 2000, pp. 1113-1120
Citations number
24
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY
ISSN journal
01478389 → ACNP
Volume
23
Issue
7
Year of publication
2000
Pages
1113 - 1120
Database
ISI
SICI code
0147-8389(200007)23:7<1113:TAEOBP>2.0.ZU;2-1
Abstract
Permanent biatrial and/or multisite atrial pacing may prevent atrial fibril lation (AF), but the effects on atrial electrophysiology remain incompletel y understood. Acute biatrial pacing was studied in 20 patients with and 28 without (controls) a history of atrial fibrillation and/or flutter. Twelve- lead electrocardiograms were recorded during pacing from the high right atr ium (RA), from the distal coronary sinus (LA), and biatrial pacing. P wave duration was measured in each lead and the difference between maximum and m inimum P duration was termed P wave dispersion. Effective refractory period s (ERPs) were measured during each pacing mode. The dispersion of P wave du ration was 35 +/- 14 ms in controls and 40 +/- 29 ms in AF patients (P = 0. 17). Compared to RA pacing, LA pacing shortened P duration in controls (127 +/- 28 to 107 +/- 16 ms, P < 0.05) and biatrial pacing markedly shortened P duration in controls (127 +/- 28 to 93 +/- 14 ms, P < 0.05) and AF patien ts (114 +/- 43 to 97 +/- 21 ms, P < 0.05). P wave dispersion rs as unaffect ed. In controls, the LA ERP was longer than the RA ERP. This phenomenon was not present in AF patients, whose LA ERP was shorter than that of controls . Biatrial pacing had no effect on atrial ERPs or the dispersion of atrial refractoriness. In conclusion, acute biatrial pacing does not affect atrial repolarization but it does cause a marked shortening of global biatrial de polarization. Distal coronary sinus pacing produces a shorter P wave than R A pacing. There is substantial dispersion in the surface P wave of the elec trocardiogram, the significance of which awaits further study.