Patent ID: 8116867
Filing Date: 2012-02-14
Classification: A61N

Abstract:
1. A method of operating an implantable cardiac stimulus device, the method comprising: capturing cardiac signals between implanted electrodes; observing whether a tachyarrhythmia is likely occurring; and selecting and implementing a mode of filtering based upon whether a tachyarrhythmia is likely occurring such that: a) if no tachyarrhythmia is likely occurring, using a first filtering, mode on the cardiac signal and using the cardiac signal, as filtered using the first filtering mode, to detect whether a cardiac event has occurred; b) if a tachyarrhythmia is likely occurring, using a second filtering mode on the cardiac signal and using the cardiac signal, as filtered using the second filtering mode, to detect whether a cardiac event has occurred; wherein the first filtering mode attenuates frequencies likely to contain T-waves of the cardiac signal more than the second filtering mode, and wherein the selecting and implementing a mode of filtering is performed based on whether a tachyarrythmia is likely occurring as follows: during a first time period, observing that a tachyarrhythmia is not likely occurring and the first filtering mode is used, and during a second time period observing that a tachyarrhythmia is likely occurring and the second filtering mode is used instead of the first filtering mode.