Electrophysiological characteristics of the human atria after cardioversion of persistent atrial fibrillation

Citation
C. Pandozi et al., Electrophysiological characteristics of the human atria after cardioversion of persistent atrial fibrillation, CIRCULATION, 98(25), 1998, pp. 2860-2865
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
CIRCULATION
ISSN journal
0009-7322 → ACNP
Volume
98
Issue
25
Year of publication
1998
Pages
2860 - 2865
Database
ISI
SICI code
0009-7322(199812)98:25<2860:ECOTHA>2.0.ZU;2-E
Abstract
Background-In animal models, induced atrial fibrillation shortens the atria l effective refractory period (ERP) and reverses its physiological adaptati on to rate. It is not clear whether this process, known as "electrical remo deling," occurs in humans. Methods and Results-We determined the ERPs, at 5 pacing cycle lengths (300 to 700 ms) and in 5 right atrial sites, after internal cardioversion of chr onic atrial fibrillation in 25 patients (14 in pharmacological washout and 11 on amiodarone). The ERPs were 195.5+/-18.8 ms in the washout and 206.3+/ -17.9 ms in the amiodarone patients (P<0.0001). ERPs were closely correlate d with the stimulation rates (r=0.95 in the washout and r=0.94 in the amiod arone group), and slope values indicating a normal (greater than or equal t o 0.07) or nearly normal (0.05 to 0.06) adaptation of ERP to rate were foun d in 77% of the 84 paced sites. The mean ERP was shorter in the lateral wal l (198.1+/-17.9 ms) than in the atrial roof (203.3+/-21.5 ms) and in the se ptum (210.5+/-20.0 ms) (P<0.03). After 4 weeks of sinus rhythm, the mean ER P, determined again in 8 patients (4 in wash-out and 4 on amiodarone), was significantly increased compared with the basal study (221.4+/-21.4 versus 197.8+/-18.3 ms, P<0.0001), Conclusions-After cardioversion of chronic atrial fibrillation, (1) atrial ERP adaptation to rate was normal or nearly normal in the majority of the c ases, (2) a significant dispersion of refractoriness between different righ t atrial sites was present, and (3) ERPs were significantly increased after 4 weeks of sinus rhythm in both washout and amiodarone patients.