Cardiac rhythm management system with cross-chamber soft blanking
AssigneeCardiac Pacemakers, Inc.
InventorsPaul A. Haefner, Gary Thomas Seim
Life of this patent
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Abstract
A cardiac rhythm management system provides cross-chamber “soft blanking.” It senses desired electrical heart activity signals associated with a first chamber electrode while reducing unwanted signals (paces and depolarizations) associated with a second chamber of the heart. Detection of a cross-chamber event associated with the second chamber increase a time-varying first chamber sensing threshold, but does not result in completely ignoring signals associated with the first chamber for an appreciable amount of time. As a result, actual first chamber events are less likely to escape detection, such that critically important therapy is properly delivered to the patient.
Claims40
A method of detecting electrical first and second chamber heart activity signals associated with first and second chambers of a heart, respectively, the method comprising:
- detecting a first chamber event indicated by the first chamber heart activity signal;
- increasing, in response to the first chamber event, a time-varying first chamber sensing threshold to a first peak value, and then decreasing the first chamber sensing threshold with time from the first peak value toward a first steady-state value;
- detecting a second chamber event indicated by the second chamber heart activity signal;
- and
- increasing, in response to the second chamber event, the first chamber sensing threshold to a second peak value, which is between the first peak and first steady-state values, and then decreasing the first chamber sensing threshold with time from the second peak value toward a second steady-state value.
A method of detecting electrical first chamber and second chamber heart activity signals associated with first and second chambers of a heart, respectively, the method comprising:
- detecting a first chamber event indicated by the first chamber heart activity signal, wherein the first chamber event consists of one of a first chamber pace pulse or a first chamber depolarization that exceeds a time-varying first chamber sensing threshold;
- increasing, in response to the first chamber event, the first chamber sensing threshold to a first peak value, and then decreasing the first chamber sensing threshold with time from the first peak value toward a first steady-state value;
- detecting a second chamber event indicated by the second chamber heart activity signal, wherein the second chamber event consists of one of a second chamber pace pulse or a second chamber depolarization that exceeds a time-varying second chamber sensing threshold;
- increasing, in response to the second chamber event, the first chamber sensing threshold to a second peak value, which is between the first peak and first steady-state values, and then decreasing the first chamber sensing threshold with time from the second peak value toward a second steady-state value;
- and
- increasing, in response to the second chamber event, the second chamber sensing threshold to a third peak value, and then decreasing the second chamber sensing threshold from the third peak value toward a third steady-state value.
A method of detecting electrical first chamber and second chamber heart activity signals associated with a first and second chambers of a heart, respectively, the method comprising:
- detecting a first chamber event indicated by the first chamber heart activity signal, wherein the first chamber event consists of one of a first chamber pace pulse or a first chamber depolarization that exceeds a time-varying first chamber sensing threshold;
- increasing, in response to the first chamber event, the first chamber sensing threshold to a first peak value, and then decreasing the first chamber sensing threshold with time from the first peak value toward a first steady-state value;
- detecting a second chamber event indicated by the second chamber heart activity signal, wherein the second chamber event consists of one of a second chamber pace pulse or a second chamber depolarization that exceeds a time-varying second chamber sensing threshold;
- and
- if the first chamber sensing threshold has decreased approximately below a predetermined comparison value, which is between the first peak and first steady-state values, then increasing, in response to the second chamber event, the first chamber sensing threshold to a second peak value, which is between the first peak and first steady-state values, and then decreasing the first chamber sensing threshold with time from the second peak value toward a second steady-state value.
A method of detecting electrical first chamber and second chamber heart activity signals associated with first and second chambers of a heart, respectively, the method comprising:
- (A) detecting a first chamber depolarization indicated by the first chamber heart activity signal, wherein the first chamber depolarization exceeds a time-varying first chamber sensing threshold;
- (B) increasing, in response to the first chamber depolarization, a time-varying first chamber sensing threshold to a first peak value, and then decreasing the first chamber sensing threshold with time from the first peak value toward a first steady-state value;
- (C) detecting a second chamber event indicated by the second chamber heart activity signal;
- (D) increasing, in response to the second chamber event, the first chamber sensing threshold to a second peak value, which is between the first peak and first steady-state values, and then decreasing the first chamber sensing threshold with time from the second peak value toward a second steady-state value;
- and
- (E) adjusting the first peak value of the first chamber sensing threshold based at least in part on an amplitude of the first chamber depolarization detected in (A).
A system for automatically adjusting a sensing threshold in a cardiac rhythm management device, the system comprising:
- a first chamber detector, electrically coupled to detect a first chamber event associated with a first chamber of a heart;
- a second chamber detector, electrically coupled to detect a second chamber event associated with a second chamber of the heart;
- and
- a threshold controller, including a time-varying first chamber sensing threshold, the threshold controller being coupled to the first chamber detector, the first chamber sensing threshold increasing, in response to the first chamber event, to a first peak value, the first chamber sensing threshold then decreasing with time from the first peak value toward a first steady-state value, the threshold detector also being coupled to the second chamber detector, the first chamber sensing threshold increasing, in response to the second chamber event, to a second peak value, which is between the first peak and first steady-state values, the first chamber sensing threshold then decreasing with time from the second peak value toward a second steady-state value.
A system for automatically adjusting a sensing threshold in a cardiac rhythm management device, the system comprising:
- a first chamber detector, electrically coupled to detect a first chamber event associated with a first chamber of a heart;
- a second chamber detector, electrically coupled to detect a second chamber event associated with a second chamber of the heart;
- and
- a threshold controller, including a time-varying first chamber sensing threshold, the threshold controller being coupled to the first chamber detector, the first chamber sensing threshold increasing, in response to the first chamber event, to a first peak value, the first chamber sensing threshold then decreasing with time from the first peak value toward a first steady-state value, the threshold detector also being coupled to the second chamber detector, wherein if thc first chamber sensing threshold has decreased at the time of the second chamber event to approximately below a predetermined comparison value that is between the first peak and first steady-state values, then:
- (a) the first chamber sensing threshold increases in response to the second chamber event to a second peak value, which is between the first peak and first steady-state values, and (b) the first chamber sensing threshold then decreases with time from the second peak value toward a second steady-state value.
Dependencies are inferred from the claim text.