Method and apparatus for determining a premature ventricular contraction in a medical monitoring device

Patent metadata

Field	Value
Publication number	US-9675270-B2
Application number	US-201615133354-A
Country	US
Kind code	B2
Filing date	Apr 20, 2016
Priority date	Apr 23, 2015
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A method and medical monitoring device for determining the occurrence of a premature ventricular contraction that includes sensing a cardiac signal and determining R-waves in response to the sensed cardiac signal, determining RR intervals between the determined R-waves, determining whether a first interval criteria is satisfied in response to the determined intervals, determining a correlation between the determined R-waves, determining whether a first correlation criteria is satisfied in response to the determined correlation, and determining the premature ventricular contraction is occurring in response to the first interval criteria and the first correlation criteria being satisfied.

First claim

I claim:

1. A method of determining occurrence of a premature ventricular contraction in a medical device, comprising:
sensing a cardiac signal and determining R-waves in response to the sensed cardiac signal;
determining RR intervals between the determined R-waves;
determining whether a first interval criteria is satisfied in response to the determined intervals;
determining a correlation between the determined R-waves;
determining whether a first correlation criteria is satisfied in response to the determined correlation, wherein determining whether a first correlation criteria is satisfied in response to the determined correlation comprises:
determining a first R-wave of the determined R-waves, a second R-wave of the determined R-waves, and a third R-wave of the determined R-waves;
determining a first correlation between the first R-wave and the third R-wave;
determining whether the first correlation is greater than a first correlation threshold;
determining a second correlation between the first R-wave and the second R-wave;
determining whether a first difference between the first correlation and the second correlation is greater than a first correlation difference threshold;
determining a third correlation between the second R-wave and the third R-wave;
determining whether a second difference between the first correlation and the third correlation is greater than the first correlation difference threshold; and
determining a premature ventricular contraction is occurring in response to the first correlation being greater than the first correlation threshold and both the first difference and the second difference being greater than the first correlation difference threshold.

2. The method of claim 1 , wherein determining whether a first interval criteria is satisfied comprises:
determining a first RR interval associated with a first R-wave of the determined R-waves, a second RR interval associated with a second R-wave of the determined R-waves, and a third RR interval associated with a third R-wave of the determined R-waves;
comparing the second RR interval with the first RR interval to generate a first interval difference;
determining whether the first interval difference is greater than an interval difference threshold;
comparing the second RR interval with the third RR interval to generate a second interval difference; and
determining whether the second interval difference is greater than the interval difference threshold.

3. The method of claim 2 , further comprising determining the premature ventricular contraction is not occurring in response to one of the first interval difference and the second interval difference not being greater than the interval difference threshold.

4. The method of claim 1 , wherein determining whether a first correlation criteria is satisfied in response to the determined correlation comprises:
determining whether the first correlation is greater than a second correlation threshold;
determining whether the first difference between the first correlation and the second correlation is greater than a second correlation difference threshold;
determining whether the second difference between the first correlation and the third correlation is greater than the second correlation difference threshold; and
determining a premature ventricular contraction is occurring in response to the first correlation being greater than the second correlation threshold and both the first difference and the second difference being greater than the second correlation difference threshold.

5. The method of claim 4 , wherein determining whether a first correlation criteria is satisfied in response to the determined correlation comprises:
determining whether the first correlation is greater than a third correlation threshold;
determining whether the first difference between the first correlation and the second correlation is greater than a third correlation difference threshold;
determining whether the second difference between the first correlation and the third correlation is greater than the third correlation difference threshold; and
determining a premature ventricular contraction is occurring in response to the first correlation being greater than the third correlation threshold and both the first difference and the second difference being greater than the third correlation difference threshold.

6. The method of claim 5 , wherein the first correlation threshold is 0.9, the second correlation threshold is 0.8, the third correlation threshold is 0.7, the first correlation difference threshold is 0.1, the second correlation difference threshold is 0.3 and the third correlation difference threshold is 0.6.

7. A method of determining occurrence of a premature ventricular contraction in a medical device, comprising:
sensing a cardiac signal and determining R-waves in response to the sensed cardiac signal;
determining a first RR interval associated with a first R-wave of the determined R-waves, a second RR interval associated with a second R-wave of the determined R-waves, and a third RR interval associated with a third R-wave of the determined R-waves;
determining whether a first interval criteria is satisfied in response to the determined intervals;
determining a correlation between the determined R-waves;
determining whether a first correlation criteria is satisfied in response to the determined correlation;
determining, in response to one of the first interval criteria and the first correlation criteria not being satisfied, whether a ratio of the second RR interval and the first RR interval is less than an interval ratio threshold;
determining whether a ratio of the second RR interval and the third RR interval is less than the interval ratio threshold; and
determining whether the second RR interval is less than an interval threshold.

8. A medical monitoring device for determining the occurrence of a premature ventricular contraction, comprising:
at least one sensing electrode for sensing a cardiac signal; and
a processor configured to determine R-waves in response to the sensed cardiac signal, determine RR intervals between the determined R-waves, determine whether a first interval criteria is satisfied in response to the determined intervals, determine a correlation between the determined R-waves, determine whether a first correlation criteria is satisfied in response to the determined correlation, wherein the processor is configured to determine a first R-wave of the determined R-waves, a second R-wave of the determined R-waves, and a third R-wave of the determined R-waves, determine a first correlation between the first R-wave and the third R-wave, determine whether the first correlation is greater than a first correlation threshold, determine a second correlation between the first R-wave and the second R-wave, determine whether a first difference between the first correlation and the second correlation is greater than a first correlation difference threshold, determine a third correlation between the second R-wave and the third R-wave, determine whether a second difference between the first correlation and the third correlation is greater than the first correlation difference threshold, and determine a premature ventricular contraction is occurring in response to the first correlation being greater than the first correlation threshold and both the first difference and the second difference being greater than the first correlation difference threshold.

9. The medical monitoring device of claim 8 , wherein the processor is configured to determine a first RR interval associated with a first R-wave of the determined R-waves, a second RR interval associated with a second R-wave of the deter

Assignees

• Medtronic Inc

Inventors

• Sarkar Shantanu

Classifications

• A61B5/0456

  Human Necessities · mapped topic

• A61B5/0468 Primary

  Human Necessities · mapped topic

• A61B5/686 Primary

  Permanently implanted devices, e.g. pacemakers, other stimulators, biochips (A61B5/6861 takes precedence) · CPC title

• A61B5/0422

  Human Necessities · mapped topic

• A61B5/04012

  Human Necessities · mapped topic