Patent ID: 8855764

Claim:
An active implantable medical device for estimating an atrial activity signal representative of a patient's atrial depolarization activity, comprising: a monobody lead comprising: a ventricular coil forming both a first shock electrode and a first detection electrode, wherein the first detection electrode is configured to detect depolarization signals from a ventricle of the patient; a supraventricular coil forming both a second shock electrode and a second detection electrode, wherein the second detection electrode is configured to detect depolarization signals from a superior vena cava of the patient; and a distal electrode comprising a third detection electrode, wherein the third detection electrode is configured to detect depolarization signals from the ventricle; and a generator comprising: a housing forming a metal reference potential electrode; and circuitry configured to: analyze the depolarization signals collected by said first, second and third detection electrodes, deliver an antitachycardia shock to the patient's ventricle, collect a first unipolar signal between the ventricular coil and the housing of the generator, collect a second unipolar signal between the supraventricular coil and the housing of the generator, perform an Independent Component Analysis (ICA) on said first and second unipolar signals, and determine, based on said Independent Component Analysis (ICA) performed on said first and second unipolar signals, an estimated atrial activity signal.