Wireless monitoring system for pulse wave velocity as response to different types of stress

More and more, daily stress is making place in our life. Lack of physical activity, lack of psychical and mental relaxation is lowering our resistance to the stimuli, perturbing our internal harmony and can be a cause for serious diseases. As response, our body reflects the stress as different physiological changes, which can be measured and monitored. One of the changes that appears is in Pulse Wave Velocity (PWV). PWV is determined by measuring the time needed by the blood pulse to travel from the heart to one of the body extremities, left hand index finger, in our case. Based on this, we created a wireless system able to measure and record the ECG signal and the Plethysmographic signal and, using signal processing, we created a software that calculates the PWV. The wireless sensors have the great advantage of giving freedom of movement to the person, therefore the PWV can be measured for a long period of time, during daily activities. Studying the results, we concluded that both physical and mental stress produce important changes in Pulse Wave Velocity.