117 – Pulse Transit Time and Velocity Calculation
Pulse Transit Time (PTT) is the time it takes the pulse pressure waveform to propagate through a length of the arterial tree. The pulse pressure waveform results from the ejection of blood from the left ventricle and moves with a velocity much greater than the forward movement of the blood itself.
With increased vessel wall stiffness (decreased compliance), DELTA V decreases and pulse wave velocity increases. With increased blood pressure, the arterial walls are more strongly stretched and pulse wave velocity increases. Accordingly, for a fixed vessel distance, as the pulse transit time increases the blood pressure decreases.
- Plethysmography - Record PPG, measure BP indirectly, look at appendage size variations, and perform sexual arousal studies using BIOPAC or 3rd-party transducers.
- Amplifiers & Interfaces - Use BIOPAC amplifiers with MP Systems, as stand-alone devices, or with 3rd-party flow meters, force plates, sono-micrometers, telemetry equipment, metabolic carts, etc.