The present invention generally relates to an implantable medical device and method for detecting and monitoring cardiac status of a patient using simultaneous multisite measurements of the intracardiac impedance and in particular to ischemia detection using the simultaneous multisite measurements. The device comprises an impedance measuring unit being connectable to a plurality of electrode configurations including a current generating device adapted to generate a current and apply the current between two electrodes of a current injecting electrode configuration of the electrode configurations and a voltage sensing device including a plurality of voltage sensing circuits arranged in parallel. Each voltage sensing circuit being connectable to a specific voltage sensing electrode configuration of the electrode configurations and being arranged to sense a voltage over the voltage sensing electrode configuration resulting from the applied current, wherein the voltage sensing circuits are capable of sensing the resulting voltages simultaneously. The device further comprises an impedance calculating module adapted to calculate a plurality of impedance values, each impedance value being based on the applied current and a resulting voltage.