Patent ID: 8768444

Claim:
An implantable medical device for coupling to a heart having a right atrium (RA), a left atrium (LA), a sinoatrial (SA) node, and an atrial septum through one or more leads including a first electrode for placement near the SA node, a second electrode for placement near the atrial septum, and a third electrode for placement in the LA, the implantable medical device comprising: a sensing circuit configured to sense a plurality of atrial electrograms using the plurality of atrial electrodes; an arrhythmia detection circuit configured to detect tachyarrhythmia; and an arrhythmia classification circuit configured to classify the detected tachyarrhythmia, the arrhythmia classification circuit including: an atrial signal mapping module configured to map an atrial activation sequence using the sensed plurality of atrial electrograms, the atrial activation sequence indicative of an order of regional depolarizations during an atrial depolarization; and an atrial pattern analyzer configured to classify the detected tachyarrhythmia using the atrial activation sequence.