Patent ID: 8942802
Filing Date: 2015-01-27
Classification: A61B,A61N

Abstract:
1. A method of operating an implantable cardiac stimulus device comprising a housing coupled to at least one lead, with a plurality of implantable electrodes, the housing containing operational circuitry for performing signal analysis and delivering therapy when indicated, the device configured for implantation in an implantee, the method comprising: capturing a cardiac signal from the implantable electrodes and detecting a cardiac event; calculating a cardiac event rate relative to the detected cardiac event; comparing the cardiac event rate to one or more rate thresholds; determining that the cardiac event rate falls within an enhanced analysis zone; based on determining that the cardiac event rate falls within the enhanced analysis zone, analyzing morphology correlation between the detected cardiac event and an elevated rate template representative of a cardiac complex with a rate between 170 and 260 bpm; finding that the cardiac event has high morphology correlation to the elevated rate template and is therefore not treatable on the basis of rate and morphology correlation combined; next, determining whether the cardiac event illustrates a QRS width that is less than a predetermined threshold width; and finding the QRS width is greater than the predetermined threshold and determining that the cardiac event indicates a cardiac condition that requires treatment, despite its correlation to the elevated rate template; wherein the elevated rate template is a dynamic template which represents an immediately preceding cardiac event.