Ventricular electrophysiology in congestive heart failure and its correlation with heart rate variability and baroreflex sensitivity: a canine model study.
OBJECTIVE
This study investigated ventricular electrophysiological characteristics and the correlation between these parameters and heart rate variability (HRV) and baroreflex sensitivity (BRS) in a canine congestive heart failure (CHF) model.


RESULTS
Haemodynamics, HRV, BRS, and ventricular electrophysiological variables were measured 4-5 weeks after sham operation (control dogs) and pacemaker implantation, and rapid right ventricular pacing at 240 bpm (CHF group). In the CHF group, significant differences from the control group in ventricular effective refractory period (VERP), monophasic action potential (MAP) duration (MAPD(90)), ventricular late repolarization duration (VLRD), the ratio of VERP to MAPD(90), dispersion of ventricular recovery time (VRT-D), and ventricular fibrillation threshold (VFT) were noted. Both BRS and the time and power domain parameters of HRV were significantly decreased in the CHF group compared with the control group, and a significant, positive correlation between HRV and BRS was identified in the CHF group. Heart rate variability and BRS were negatively and significantly correlated with VLRD and VRT-D, and were positively correlated with VERP/MAPD(90) and VFT in the CHF group.


CONCLUSIONS
These results suggest that ventricular electrophysiological characteristics correlated with abnormal autonomic nerve function may have important effects on sudden cardiac death. Further research is warranted.
Zhou
Shu-Xian
SX
Department of Internal Medicine, Division of Cardiology, Second Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People's Republic of China. zzhoushuxian@yahoo.com.cn
Lei
Juan
J
Fang
Chang
C
Zhang
Yu-Ling
YL
Wang
Jing-Feng
JF
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001341:Autonomic Nervous System / Q000503:physiopathology; D017704:Baroreflex / Q000502:physiology*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D004195:Disease Models, Animal; D004285:Dogs; D022062:Electrophysiologic Techniques, Cardiac; D006333:Heart Failure / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D018754:Ventricular Dysfunction / Q000503:physiopathology*; D014693:Ventricular Fibrillation / Q000503:physiopathology