Original Research Article
Year: 2018 | Month: March | Volume: 8 | Issue: 3 | Pages: 226-231
Time and Frequency Domain Analysis of Heart Rate Variability (HRV) In Response to Cold Stress in Subjects with Family History of Hypertension
Amrendra Jha, Bishuddha Bhattarai, Bom Bahadur Kunwar, Santosh Pant
Department of Basic and Clinical Physiology, B.P. Koirala Institute of health sciences, Dharan, Nepal
Corresponding Author: Amrendra Jha
Objective: Autonomic nervous system plays a crucial role in the development of hypertension and autonomic dysfunction underlies the initiation and maintenance of hypertension. Elevated blood pressure has been known to be a huge risk factor for cardiovascular disease later in life and leads to increased morbidity and mortality. In this study, we aimed to study the effect of cold stress on heart rate variability and prevalence of cardiovascular risks in subjects with hypertensive parents
Methods: A total of 30 subjects and 30 healthy controls were recruited in the study. Their anthropometrical and cardiovascular parameters were recorded. For recording HRV, the resting cardiac cycles (R-R intervals) signals at spontaneous respiration were recorded for 5 min in supine position after 15 min of supine rest. The HRV was recorded in both groups using Polar S810i heart rate monitor before, during and after the cold pressor test (CPT).
Results: Analysis was done for baseline and post-CPT period within the study group, in both time and frequency domain components of HRV. Two time domain parameters; SDNN and RMSSD were found to differ significantly pre and post-CPT, with both of the parameters being more in the post-CPT period, as it can be seen from the table 4.
Conclusion: RMSSD was decreased (p value= 0.042) and SDNN was increased (p value= 0.048: borderline) post-CPT in subjects with family history of hypertension, suggesting that some amount autonomic dysfunction is manifested at early age.
Key words: HRV, CPT, Blood pressure