Telemetry-derived heart rate variability responses to a physical stressor

Area of Science:

• Cardiovascular Physiology
• Autonomic Nervous System Function
• Biomedical Engineering

Background:

• Heart rate variability (HRV) analysis assesses autonomic control of heart rate, crucial for cardiovascular health.
• Electrocardiogram (ECG) is the standard for HRV but impractical for large population studies.
• Telemetric devices offer a potential alternative for remote and widespread HRV monitoring.

Purpose of the Study:

• To evaluate the validity and reliability of telemetry-derived HRV measurements.
• To assess HRV responses to an orthostatic challenge using a telemetric device.
• To compare telemetric HRV data with traditional ECG recordings.

Main Methods:

• Twenty healthy adults underwent testing on three separate mornings.
• R-R intervals were recorded using a telemetric device during supine rest, tilt, and recovery.
• ECG was used for concurrent validity comparison, analyzing standard deviation of normal-to-normal intervals (SDNN), root-mean-square of successive differences (RMSSD), and low-frequency (LF)/high-frequency (HF) spectral power.

Main Results:

• Excellent agreement (r=0.89-1.00) was found between telemetric and ECG devices across all conditions.
• The telemetric device demonstrated excellent between-day reliability (intraclass coefficients > 0.75) for RMSSD, SDNN, and HF.
• RMSSD and HF showed greater reliability (lower RC%) compared to SDNN, which did not significantly respond to the orthostatic challenge.

Conclusions:

• Telemetric HRV assessment, particularly using RMSSD and HF parameters, is valid and reliable.
• This method provides a sensitive measure of autonomic heart rate control.
• Telemetric HRV is a practical tool for large-scale population studies investigating cardiovascular function.