Medical patch for simultaneously sensing ECG signals and impedance-indicative electrical signals

A method, comprising:

• providing a medical patch, the medical patch comprising:
• a substrate, configured to attach externally to a patient;
• an electrode, which is coupled to the substrate and is configured to sense electrocardiogram (ECG) signals from a heart of the patient, and to further sense active current location (ACL) signals;
• and
• circuitry, which is coupled to the substrate and comprises a shared amplifier that is configured to simultaneously amplify the ECG signals and the ACL signals,
• wherein the circuitry comprises an ECG filter and an ACL filter, which are configured to filter amplified ECG signals and amplified ACL signals, respectively,
• wherein the ACL filter comprises a band-pass filter (BPF) having a passband that matches the frequency range of the ACL signals, and the ECG filter comprises a low-pass filter (LPF) having a cutoff frequency of at least ten Hz,
• sensing, by the electrode, the ECG signals and the ACL signals;
• amplifying simultaneously, using the circuitry, the ECG signals and the ACL signals;
• and
• performing a medical procedure using amplified ECG signals and amplified ACL signals from an output of the amplifier.