US 9,802,056 B2 · Accurate cardiac event detection in an implantable cardiac stimulus device

Abstract

Methods, systems, and devices for signal analysis in an implanted cardiac monitoring and treatment device such as an implantable cardioverter defibrillator. In some illustrative examples, detected events are analyzed to identify changes in detected event amplitudes. When detected event amplitudes are dissimilar from one another, a first set of detection parameters may be invoked, and, when detected event amplitudes are similar to one another, a second set of detection parameters may be invoked. Additional methods determine whether the calculated heart rate is “high” or “low,” and then may select a third set of detection parameters for use when the calculated heart rate is high.

Claims12

Dependent claims

A method of event detection in an implantable cardiac stimulus device having a plurality of electrodes adapted for implantation in a patient, the method comprising:

capturing electrical signals from the electrodes;
comparing captured electrical signals to a detection threshold that varies with time following a detection profile;
when the captured electrical signals cross the detection threshold, declaring a detected event;
determining whether either of these conditions is met:
a) the detected event is similar to a prior detected event, or
b) whether the detected event is separated from an immediately prior detected event by an interval exceeding an interval threshold;
selecting from between first and second variants of a selected detection profile for use in subsequent event detection as follows:
if b) is met, then selecting the first variant;
if b) is not met and a) is met, then selecting the first variant;
and else selecting the second variant;
and
detecting a subsequent cardiac event using the selected variant of the selected detection profile.

9 more elements

An implantable cardiac stimulus device having a plurality of electrodes adapted for implantation in a patient and operational circuitry coupled to the plurality of electrodes which is configured to perform a method comprising:

capturing electrical signals from the electrodes;
comparing captured electrical signals to a detection threshold that varies with time following a detection profile;
when the captured electrical signals cross the detection threshold, declaring a detected event;
determining whether either of these conditions is met:
a) the detected event is similar to a prior detected event, or
b) whether the detected event is separated from an immediately prior detected event by an interval exceeding an interval threshold;
selecting from between first and second variants of a selected detection profile for use in subsequent event detection as follows:
if b) is met, then selecting the first variant;
if b) is not met and a) is met, then selecting the first variant;
and else selecting the second variant;
and
detecting a subsequent cardiac event using the selected variant of the selected detection profile.

9 more elements

An implantable cardiac stimulus device having a plurality of electrodes adapted for implantation in a patient and means for analyzing signals captured by the plurality of electrodes, wherein the means for analyzing is configured to perform a method comprising:

comparing captured electrical signals from the plurality of electrodes to a detection threshold that varies with time following a detection profile;
when the captured electrical signals cross the detection threshold, declaring a detected event;
determining whether either of these conditions is met:
a) the detected event is similar to a prior detected event, or
b) whether the detected event is separated from an immediately prior detected event by an interval exceeding an interval threshold;
selecting from between first and second variants of a selected detection profile for use in subsequent event detection as follows:
if b) is met, then selecting the first variant;
if b) is not met and a) is met, then selecting the first variant;
and else selecting the second variant;
and
detecting a subsequent cardiac event using the selected variant of the selected detection profile.

8 more elements

Dependencies are inferred from the claim text.

Accurate cardiac event detection in an implantable cardiac stimulus device

Life of this patent

Accurate cardiac event detection in an implantable cardiac stimulus device

Life of this patent

Abstract

Claims12