Effect of severity of myocardial failure on heart rate variability in Doberman pinschers with and without echocardiographic evidence of dilated cardiomyopathy.
OBJECTIVE
To determine whether heart rate variability (HRV) is reduced in Doberman Pinschers with dilated cardiomyopathy.


METHODS
Case series.


METHODS
62 overtly healthy Doberman pinschers.


METHODS
Heart rate variability was analyzed in time and frequency domains from data obtained during 24-hour ambulatory electrocardiographic Holter recordings in 41 overtly healthy Doberman pinschers with normal echocardiograms and 21 overtly healthy Doberman pinschers with abnormal echocardiograms.


RESULTS
Heart rate variability usually was greater during night versus day, and 2 dogs with the most severe myocardial failure had reduced HRV.


CONCLUSIONS
Reduced HRV was detected only in Doberman Pinschers with the most severe myocardial failure. Thus, HRV in less severely affected dogs is not reduced, or the normal sinus arrhythmia of dogs renders HRV relatively insensitive. Analysis of HRV did not provide additional information relative to the severity of left ventricular dysfunction or risk of sudden death from that which could be derived from echocardiography, analysis of Holter recordings, and signal-averaged electrocardiography.
Calvert
C A
CA
Department of Small Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602, USA.
Wall
M
M
D000818:Animals; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology / Q000662:veterinary*; D002940:Circadian Rhythm / Q000502:physiology; D004283:Dog Diseases / Q000503:physiopathology*; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary; D015716:Electrocardiography, Ambulatory / Q000662:veterinary; D006339:Heart Rate / Q000502:physiology*; D012720:Severity of Illness Index; D018754:Ventricular Dysfunction