Early Left Ventricular Dysfunction Elicits Activation of Sympathetic Drive and Attenuation of Parasympathetic Tone in the Paced Canine Model of Congestive Heart Failure

Abstract

The results indicate that autonomic imbalance as reflected in an abnormal pattern of heart rate variability evolves early in the course of ventricular systolic dysfunction consisting of both a significant increase in sympathetically influenced low-frequency heart rate variability and a significant reduction of parasympathetically mediated high-frequency variability. The early appearance of these autonomic abnormalities suggests that autonomic imbalance plays a significant role in promoting the progression of circulatory failure.