Heart rate variability indices for very short-term (30 beat) analysis. Part 1: survey and toolbox

Area of Science:

• Physiology
• Biomedical Engineering
• Cardiology

Background:

• Heart rate variability (HRV) analysis is crucial for understanding autonomic nervous system (ANS) activity.
• Traditional HRV analysis often requires longer, steady-state recordings.
• Dynamic physiological states, such as during drug administration or exercise onset/offset, necessitate methods for very short-term HRV analysis.

Purpose of the Study:

• To survey and identify existing HRV indices applicable to very short-term (e.g., <60 seconds) analysis.
• To find reliable HRV measures for monitoring dynamic ANS activity outside of steady-state conditions.
• To compile a toolbox of validated HRV indices for short-term physiological monitoring.

Main Methods:

• Conducted a comprehensive literature survey of published HRV analysis methods.
• Included time-domain, frequency-domain, respiratory sinus arrhythmia, Poincaré plot, and heart rate characteristics.
• Screened 115 identified indices using short data segments, removing invalid or redundant measures.

Main Results:

• Identified a comprehensive list of 115 HRV indices from published literature.
• Screened and coded indices, retaining 70 unique measures that produced finite results with 60-second data segments.
• These 70 indices form a potential 'Toolbox' for very short-term HRV analysis.

Conclusions:

• A significant number of HRV indices exist that are potentially applicable to very short-term analysis.
• The identified indices provide a foundation for analyzing dynamic ANS activity.
• Further validation against physiological data is essential before clinical application of these short-term HRV indices.