Power Spectral Analysis of Heart Rate Variability in Hypertension: A Cross Sectional Study from Davanagere, South India

Abstract

Background:
Hypertension is the most common disease. It markedly increases both mortality and morbidity. Hypertension is associated with autonomic dysregulation. Heart rate variability (HRV) is a useful noninvasive, powerful tool for quantitative assessment of cardiac autonomic function. The aim of this study was to assess the cardiac autonomic function status in patients with essential hypertension by analyzing frequency domain measures of heart rate variability.

Methods:
50 hypertensive and 50 normotensive male subjects between the age group of 40-60 years were selected. Computerized ECG system with Niviqure software was used for the study. Frequency domain measures of heart rate variability such as Low frequency (LF), High frequency (HF) and LF/HF ratio were assessed to observe both sympathetic and parasympathetic nerve function status. Statistical analysis was done by using unpaired “t” test.

Results:
Significant increase in the SBP, DBP, PP and MAP among hypertensives (p<0.001). Mean low frequency (Hz), LF power (ms2) and LF (nu) was significantly (p< 0.001) reduced in hypertensive subjects compared to normotensives. There was reduction in values of Mean HF (ms2) in hypertensive. But it was not statistically significant compared to normotensives.

Conclusion:
Cardiac autonomic function tests can predict the future risk of hypertension, which necessitates intervention at the primary health care level for its prevention.