Using of Spectral Analysis of Heart Rate Variability for Increasing Reliability of Bicycle Ergometry Results

Abstract

The aim was to study the suitability of heart rate variability (HRV) spectral parameters for evaluations of bicycle ergometry results in coronary heart disease (CHD) patients. Our study included 243 male CHD patients aged 49±8 years. The coronary atherosclerosis was assessed by coronary angiography. The results of bicycle ergometry, Doppler echocardiography and HRV spectral analysis were analyzed also. The duration of each stage of bicycle ergometry was 3 min, the initial load value was 25 W. Dynamic load continued till the patient reached 75% of heart rate from his maximal age level. The maximal level of load achieved (i.e. load tolerance) was taken into consideration. We calculated sensitivity (Se), specificity (Sp), likelihood ratios of positive (LR+) and negative (LR-) bicycle ergometry results. All patients had similar clinical characteristics. LR+ becomes maximal under the moderate load tolerance. LR- is maximal in the CHD patients with high load tolerance. Thus, the excessiveness of false-negative results of bicycle ergometry is in CHD patients with high load tolerance. Reliability of results of bicycle ergometry increased under using assessments of low-frequency (LF) range power of HRV spectrum.Thus, using of LF range power of HRV spectrum increases a reliability of bicycle ergometry (or other load tests) results in CHD patients.