Arterial pressure pulse wave separation analysis using a multi-Gaussian decomposition model.

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Medical Signal Processing

Background:

• Traditional wave separation analysis (WSA) for blood pulse waves requires simultaneous pressure and flow velocity measurements.
• Existing flow velocity-based WSA methods are primarily limited to the aortic site.
• There is a need for WSA methods applicable to non-aortic sites, like the carotid artery, without relying on flow velocity.

Purpose of the Study:

• To develop and evaluate a multi-Gaussian decomposition (MGD) modelled wave separation analysis (MGD_WSA) for carotid artery pressure waveforms.
• To assess the performance of MGD_WSA without requiring measured or modelled flow velocity information.
• To compare MGD_WSA results against established flow-based WSA methods.

Main Methods:

• The proposed MGD_WSA decomposes arterial pressure waveforms using weighted and shifted multi-Gaussians.
• These components are uniquely combined to derive forward (P_F(t)) and backward (P_B(t)) pressure waves.
• The method was evaluated using a database of healthy virtual subjects and compared to reference flow-based WSA.

Main Results:

• The MGD modelled pressure waveform achieved a root-mean-square error (RMSE) < 0.35 mmHg.
• Reliable forward and backward pressure components were obtained with a group average RMSE < 2.5 mmHg.
• Pulse pressures and reflection indices showed strong correlations (r > 0.96 and r > 0.83, respectively) with reference methods, with insignificant bias.

Conclusions:

• This study successfully reports wave separation analysis for carotid pressure waveforms independent of flow conditions.
• The MGD_WSA method offers a novel approach for analyzing vascular dynamics in non-aortic sites.
• This technique has the potential to expand and adapt vascular health assessment tools incorporating pulse wave dynamics.