A blood pressure monitoring system is provided comprising: an impedance monitoring circuit configured to detect an occurrence of a blood pulse wave ejection from the heart； a blood pulse detection circuit detect to an arrival of the blood pulse wave at a body site peripheral to the heart； and a processor configured to compute pulse transit time (PTT) based at least in part upon a difference in a time of occurrence of the blood pulse wave ejection from the heart first signal and a time of occurrence of the arrival of the blood pulse wave at a body site peripheral to the heart.
