Autonomic function in Kawasaki disease with myocardial infarction: usefulness of monitoring heart rate variability.
BACKGROUND
Despite anticoagulant therapy, many patients with Kawasaki disease and giant coronary artery aneurysm develop myocardial infarction. These patients have a high risk of sudden death, but the etiology is not clear. We studied autonomic function and the possibility of malignant ventricular arrhythmia through heart rate variability.


METHODS
We studied six Kawasaki disease patients with myocardial infarction and 16 normal controls. Heart rate variability was investigated using a 24 h electrocardiogram. We assessed the standard deviation from the mean of the normal R-R intervals (SDNN), the proportion of adjacent R-R intervals with a difference greater than 50 msec (pNN50) and the root-mean square of successive R-R differences as time-domain analysis (rMSSD). We assessed very low-frequency power, low-frequency power (LF), high-frequency power (HF) and the LF/HF ratio in frequency-domain analysis.


RESULTS
There was no significant difference in SDNN, but there was a significant difference in pNN50 and rMSSD. Patients with Kawasaki disease showed lower HF and higher LF/HF than normal controls.


CONCLUSIONS
Our findings suggest that patients with Kawasaki disease and myocardial infarction show decreased vagal activity, which could cause malignant arrhythmia.
Kikuchi
Yutaka
Y
Department of Pediatrics, Jichi Medical School, Tochigi, Japan. ykikuchii@jichi.ac.jp
Sato
Yuko
Y
Ichihashi
Kou
K
Shiraishi
Hirohiko
H
Momoi
Mariko Y
MY
D000293:Adolescent; D001341:Autonomic Nervous System / Q000503:physiopathology; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000150:complications / Q000503:physiopathology*; D009203:Myocardial Infarction / Q000209:etiology / Q000503:physiopathology*