Clinical significance of heart rate variability for the monitoring of cardiac autonomic neuropathy in end-stage renal disease patients

Background and aims: The aim of this study is to determine whether the measurement of continuous heart rate variability (HRV) is useful in the evaluation of cardiac autonomic neuropathy (CAN) in end-stage renal disease (ESRD) patients. Methods and results: This cross-sectional study was performed at Seoul St. Mary's hospital between June 2017 and February 2018. Seventy-seven ESRD patients, and 29 healthy controls (HCs) were asked to wear a continuous ambulatory HRV monitor for 24 h. General cardiac function was evaluated using transthoracic echocardiogram (TTE), pulse wave velocity (PWV), coronary calcium scoring (CCS), and 24-h ambulatory blood pressure monitoring (ABPM). HRV parameters of ESRD patients and HCs, and the correlation of HRV parameters with cardiovascular screening methods were observed. All HRV parameters were significantly decreased in ESRD patients compared to HCs (P < 0.001). In the correlation analysis between TTE results and HRV parameters, 24-h standard deviation of all N–N intervals (24SDNN), 24-h standard deviation of sequential 5-min N–N interval means (24DANN) and Low Frequency Power/High Frequency Power (LF/HF) ratio showed negative correlations with E/e’, LAVI and TR velocity which are representative indices for the diastolic function of the heart (P < 0.05). HRV parameters showed negative correlations with baPWV, CCS, and 24-h ABPM results as well (P < 0.05). Hemoglobin and serum albumin showed positive correlations with HRV parameters, and glucose, BUN, creatinine, and iPTH levels showed negative correlations (P < 0.05). Conclusion: Continuous HRV monitoring may be a useful tool for the evaluation of CAN in ESRD.