Method for discriminating between ventricular and supraventricular arrhythmias
First Claim
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.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention is directed toward a detection architecture for use in implantable cardiac rhythm devices. The detection architecture of the present invention provides methods and devices for discriminating between arrhythmias. Moreover, by exploiting the enhanced specificity in the origin of the identified arrhythmia, the detection architecture can better discriminate between rhythms appropriate for device therapy and those that are not.
-
Citations
5 Claims
-
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. - View Dependent Claims (2)
-
-
3. An implantable cardiac stimulus device comprising a canister housing operational circuitry and a lead system coupled to the canister, the operational circuitry being electrically connected to a plurality of sensing electrodes disposed as part of the lead system and/or canister, the operational circuitry configured to perform a cardiac signal analysis method comprising the following steps:
-
detecting a cardiac event by observation of electrical signals captured using at least some of the sensing electrodes; calculating a cardiac event rate relative to the detected cardiac event; determining the cardiac event rate falls within an enhanced analysis zone; analyzing morphology correlation of the cardiac event relative to an elevated rate template representative of a cardiac complex with a rate between 170 and 260 bpm; determining that the cardiac event has high morphology correlation relative to the elevated rate template and is therefore not treatable on the basis of rate and morphology correlation combined; analyzing whether the cardiac event illustrates a QRS width that is greater than a predetermined threshold; and
one of;determining that the cardiac event is narrower than the predetermined threshold and, in view thereof, determining that the cardiac event does not indicate cardiac stimulus;
ordetermining that the cardiac event is wider 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.
-
-
4. 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 implantable electrodes disposed in the implantee and detecting a cardiac event; calculating a cardiac event rate relative to the detected cardiac event; performing a tiered decision-making process configured to include the following steps; a) determining whether the cardiac event rate is in a predefined elevated rate range; b) analyzing whether the cardiac event has a high morphology correlation relative to an elevated rate template representative of a cardiac complex with a rate between 170 and 260 bpm; c) analyzing whether the cardiac event illustrates a QRS width that is greater than a predetermined threshold; wherein the tiered decision making process includes; after finding that a) is true, performing b; after finding that b) yields high correlation, while the event rate is in the predefined elevated rate range, determining that the combination of rate and morphology correlation does not support therapy delivery without more information and therefore invoking c) and, when c) is invoked, further finding the cardiac event is wider than the predetermined threshold, and determining that the cardiac event indicates cardiac stimulus even though the cardiac event correlates to the elevated rate template; wherein the elevated rate template is a dynamic template which represents an immediately preceding cardiac event. - View Dependent Claims (5)
-
Specification