Patent ID: 8777851

Claim:
An implantable device-implemented method of early detection and monitoring of congestive heart failure in a patient, which comprises the steps of: measuring local impedance of a portion of the patient's body generally occupied by the lungs solely through surface mounted electrodes on the device with the device implanted subcutaneously in the patient's body, detecting when the local impedance measurements using said surface mounted electrodes are indicative of a condition of edema, detecting the patient's heart rate/activity pattern through said surface mounted electrodes while concurrently monitoring said local impedance measurements to evaluate cardiopulmonary status of the patient, and evaluating said congestive heart failure based on (1) said edema and (2) said cardiopulmonary status; wherein at least some of said surface mounted electrodes used in said measuring step are the same surface mounted electrodes used in said detecting the patient's heart rate/activity pattern step.