Pulse Wave Velocity Techniques

Abstract

Recently, pulse wave velocity (PWV), or its reciprocal pulse transit time (PTT), has been intensively investigated as a promising technique for continuous, cuffless, and noninvasive blood pressure (BP) monitoring. BP is mathematically derived through PTT, or the “time delay” in propagation of pressure waves in the vascular system, which can be easily derived from two pulse signals, including electrocardiography (ECG) and pulse plethysmography (PPG) signals, together with adequate calibration procedure. Practical steps in applying this method as well as mathematical models in estimating BP were reviewed; while limitations of this approach, such as the need for individual calibration and the need for a reasonably stable condition were discussed. The future of this technology can be potentially used in, but not limited to, continuous BP monitoring, BP change tracker, and trigger for absolute BP measurement. Furthermore, with machine learning, the initially extract surrogate cardiovascular indexes from physiological signals can be used to train and adapt to the model to further improve the accuracy of BP prediction.