Abstract: This paper is concerned with a new wearable system, which is able to monitor several vital signals and physiological variables in order to determine the cardiopulmonary activity status during emergencies. The innovative system consists of a multi-modal broad-band piezoelectric transducer based on PVDF polymer integrated into a textile belt wrapped around the chest. An advanced electronic control unit, floating power supply and wireless communication support make it suitable for portable monitoring during critical cardiopulmonary failures. The multi-modal transducer is innovative in that only one sensitive element is employed to work as either an ultrasound transceiver or piezoelectric sensor. The ultrasound transceiver is enabled to work at high frequency, i.e. it is excited by suitable pulses to emit an ultrasonic wave, which penetrates the body and receives the echo signals bouncing off the biological interfaces having different acoustic impedance. The piezoelectric sensor works at low frequency and acquires both signals generated by heart apex movements and the mechanical movement of the chest induced by respiration. This multimodality is allowed by a broad band of sensitivity jointly at a low value of the figure of merit (Q). Moreover, the transducer thickness is thin enough to assure a good adaptability to the biological site, and it is equipped with an advanced control unit enabling to switch from high to low working frequency. If jointly used along with an ECG wearable Holter, this transducer can be used to provide an exhaustive picture of the health status of the subject in the diagnostic and prognostic domains.