Analyze the characteristics of heart rate variability in children with Kawasaki disease

Abstract

Objective To explore characteristics of heart rate variability (HRV) in children with Kawasaki disease. Methods From October 2012 to August 2014, a total of 120 children with Kawasaki disease were selected into this study (Kawasaki disease group). According to whether complicated with coronary artery expansion or not, Kawasaki disease group were further divided into coronary artery expansion sub-group (CAL sub-group, n=46) and no coronary artery expansion sub-group (NCAL sub-group, n=74). Meanwhile, another 57 children received health examination were selected into control group in this study randomly. The HRV time domain and frequency domain over 24 hours were performed in Kawasaki disease group and control group. HRV time domain measures included standard deviation of N-N intervals(SDNN), standard deviation of all mean 5-minute N-N intervals(SDANN), standard deviation of all N-N intervals for all 5-minute segments of 24 hours(SDNN index), root mean squared successive diference(rMSSD), percent of N-N 50 in the total number N-N intervals(PNN50). HRV frequency domain measures included very low frequency(VLF), low frequency(LF), high frequency(HF), and LF/HF. There were no significant differences between two groups in general clinical data, such as gender constituent ratio, age. The study protocol was approved by the Ethical Review Board of Investigation in Human Being of Chengdu Women's & Children's Central Hospital. Informed consent was obtained from the parents of each participating child. Results The levels of SDNN, SDNN index, rMSSD and PNN50 of HRV in Kawasaki disease group were significantly lower than those in control group (t=5.82, 2.20, 4.81, 3.64; P<0.05), but there were no significant difference between two groups in the level of SDANN(t=1.92, P=0.085). The levels of VLF, LF, and HF of HRV in Kawasaki disease group were significantly lower than those in control group (t=2.50, 4.50, 2.85; P<0.05), and the level of LF/HF in Kawasaki disease was significantly higher than that in control group (t=2.14, P=0.041). Compare with NCAL sub-group, the levels of SDNN, SDANN, PNN50, and LF decreased progressively in CAL sub-group, and there were significant differences (t=3.38, 2.46, 2.15, 7.92; P<0.05). Conclusions Cardiovascular autonomic nervous functional lesion could be found in children with Kawasaki disease. HRV has a certain value to predict the development and prognosis of children with Kawasaki disease. Key words: Mucocutaneous lymph node syndrome; Heart rate variability; Child