Patent ID: 8805498

Claim:
An implantable device with ischemia detection and heart pacing capability, including: at least one electrode adapted for implantation in a body; circuitry coupled to the electrode to sense signals therefrom and to generate corresponding digital signals; pacemaker circuitry; a processor configured to: distinguish between at least two beat types, including ventricularly paced and supraventricular beats; collect data from the digital signals for the ventricularly paced and the supraventricular beats within a plurality of heart beat segments; derive a ventricularly paced baseline for use with the ventricularly paced beats and a supraventricular baseline for use with the supraventricular beats, wherein the ventricularly paced baseline and the supraventricular baseline are indicative of a normal value of a heart signal parameter over a period of at least one hour defining a first time interval; (a) determine whether a current beat during a second time interval is supraventricular or paced, thereby establishing a current beat type; (b) determine whether the baseline corresponding to the current beat type is valid for the second time interval; (c) when the corresponding baseline in said first time interval is valid for said second time interval, apply predetermined ischemia criteria based on the corresponding baseline to the current beat; (d) when the corresponding baseline is invalid for said second time interval, apply ischemia criteria selected from the group of: collecting a plurality of the current beat type over a predetermined time interval; apply a time rate of change of a heart rate feature over said predetermined time interval; or apply the baseline in said first time interval with a correction factor over said second time interval.