Evaluation of the correlation between blood pressure and pulse transit time

The arterial blood pressure is an essential physiological parameter for health monitoring. Most blood measurement devices determine the systolic and diastolic arterial blood pressure through the inflation and the deflation of a cuff. This method is uncomfortable to the user and may cause anxiety which in turns can affect the blood pressure (white coat syndrome). This paper investigates a cuff-less non-intrusive approach to measure arterial blood pressure that is suitable for continuous measurement. The approach is based on measuring the delay between the R-peak of the electrocardiogram (ECG) signal and the peaks of the finger photoplethysmograph (PPG) signal. The results of this paper show a high correlation between the blood pressure and the pulse transit time (PTT). Different polynomial regressions are applied for further estimation. The paper uses actual ECG, PPG and blood pressure measurements extracted from the MIMIC database that contains clinical signal data reflecting real measurements. The simulation results verify that the delay (PTT) between the R-peak of the ECG signal and the peaks of the finger PPG signal have a high correlation with arterial blood pressure and can be used as an indicator of the arterial blood pressure.