The invention provides a system for measuring stroke volume (SV), cardiac output (CO), and cardiac power (CP) from a patient having: 1) an impedance sensor connected to at least two electrodes with impedance circuit that processes analog signals from the electrodes to measure an impedance signal (TBEV waveform)； 2) an ECG sensor connected to at least two electrodes and including an ECG circuit that processes analog signals from the electrodes to measure and ECG signal； 3) an optical sensor connected to a optical probe and including an optical circuit that processes signals from the probe to measure at least one optical signal from the patient； 4) a processing system that analyzes the ECG, TBEV and optical signals to determine SV, typically worn on the patient's wrist and connected through a wired interface to the optical sensor, and through either a wired or wireless interface to the TBEV and ECG sensors.
