Pulse sharpness as a quantitative index of vascular aging

Area of Science:

• Cardiovascular physiology
• Biomedical engineering
• Medical diagnostics

Background:

• Arterial stiffness and vascular aging are critical indicators of cardiovascular health.
• Existing metrics like the radial augmentation index (rAIx) have limitations in diverse waveform morphologies.
• A need exists for a robust, quantitative measure of pulse wave characteristics reflecting vascular status.

Purpose of the Study:

• To develop a novel algorithm for quantifying pulse sharpness.
• To assess the utility of this pulse sharpness index (PSI) in reflecting vascular aging and arterial stiffness.
• To compare the performance of PSI against the established radial augmentation index (rAIx).

Main Methods:

• Developed the pulse sharpness index (PSI) using end-point angle and virtual height.
• Analyzed 528 radial pulse waveforms.
• Compared PSI with rAIx across different waveform types, sexes, and age groups; correlated with arterial stiffness.

Main Results:

• The PSI demonstrated applicability across various pulse morphologies, unlike rAIx.
• Significant sex differences and age-dependent decreases were observed for both rAIx and PSI.
• PSI showed strong correlations with age (r=-0.550) and arterial stiffness (r=-0.700), outperforming rAIx in some aspects.
• A regression model incorporating PSI, age, sex, and heart rate accurately predicted arterial stiffness (R²=0.701), with PSI being the most influential factor.

Conclusions:

• The developed pulse sharpness index (PSI) is a robust quantitative measure for vascular aging.
• PSI offers advantages over rAIx in assessing arterial stiffness, particularly with varied pulse waveforms.
• PSI shows significant potential as a clinical tool for inferring arterial stiffness and monitoring vascular health.