HEART MONITORING DEVICE AND METHOD

• US 20100106033A1
• Filed: 10/24/2008
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Biotronik SE & Company KG
• Original Assignee: Biotronik VI Patent AG (Biotronik SE & Company KG)
• Inventors: Muessig, Dirk, LIAN, Jie
• Granted Patent: US 8,019,407 B2
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: G06F 2218/10 by analysing the shape of a waveform, e.g. extracting parameters relating to peaks
• CPC Class Codes: G06F 2218/18 by plotting the signal segments against each other, e.g. analysing scattergrams

Abstract

A heart monitor for processing input signals that represent periodically reoccurring events in a sequence of heart cycles. According to the invention graphical data representing a scatter plot of at least two dimensions, one dimension representing interval duration or its inverse and the other dimension representing change of duration or its inverse, respectively, are generated. The scatter plot comprises data points of which each data point represents heart interval duration or its inverse plotted against the change of duration with respect to a neighboring interval or the inverse of said change respectively.

Claims

1. A heart monitor that processes input signals that represent periodically reoccurring events in a sequence of heart cycles, comprising:

a signal input;

an event detector connected to said signal input wherein said event detector is adapted to respond to signal features that represent reoccurring cardiac events obtained via said signal input;

at least one timer connected to said event detector and adapted to determine a duration or its inverse of a time interval between two successive signal features that represent a cardiac event;

an interval evaluation stage connected to said at least one timer and being adapted to determine a change of a duration of two successive intervals or an inverse thereof; and

,

a processing stage connected to said interval evaluation stage and said at least one timer and being adapted to generate graphical data that represents a scatter plot of at least two dimensions, one dimension that represents interval duration or its inverse and another dimension that represents change of duration or its inverse respectively, wherein the scatter plot comprises data points of which each data point represents the interval duration or its inverse plotted against the change of duration with respect to a neighboring interval or the inverse of said change of duration respectively.

2. The heart monitor of claim 1, wherein said signal input is adapted to receive an electrocardiogram signal.

3. The heart monitor of claim 2, wherein said signal input is connected or can be connected to an electrode lead having at least a sensing electrode that is adapted to pick up myocardial potentials in a heart.

4. The heart monitor of claim 2, wherein the event detector is adapted to detect signal features that represent QRS complexes in an electrocardiogram.

5. The heart monitor of claim 2, wherein the event detector is part of an event sensing stage of an implantable medical device.

6. The heart monitor of claim 1, wherein said signal input is adapted to receive a marker signal wherein a marker represents the cardiac event.

7. The heart monitor of claim 1, wherein said processing stage is connected to an output configured to display the scatter plot as represented by said graphical data.

8. The heart monitor of claim 1, wherein said processing stage is connected to an analyzer stage that is adapted to process said graphical data and to detect a cluster of data points in said scatter plot and to generate the output signal, that depends on a location of one or more clusters of data points in said scatter plot.

9. The heart monitor of claim 8, wherein said analyzer stage that is adapted to compare the location of one or more clusters of data points in said scatter plot to reference data and to generate the output signal, that depends on a similarity of the location of one or more clusters of data points in said scatter plot to said reference data.

10. The heart monitor of claim 8, wherein said processing stage and said analyzer is part of an implantable medical device.

11. The heart monitor of claim 8, wherein said processing stage and said analyzer is part of an external device that is adapted to be wirelessly connected to an implantable medical device that generates an input signal.

12. A method of processing input signals that represent periodically reoccurring events in a sequence of heart cycles, comprising:

obtaining a signal that represents periodically reoccurring events in a sequence of heart cycles;

detecting signal features that represent the periodically reoccurring cardiac events;

determining a duration or its inverse of a time interval between two successive signal features that represent a cardiac event;

determining a change of a duration of two successive intervals or an inverse thereof;

generating graphical data that represents a scatter plot of at least two dimensions, one dimension that represents interval duration or its inverse and another dimension that represents change of duration or its inverse respectively, wherein the scatter plot comprises data points of which each data point represents the interval duration or its inverse plotted against the change of duration with respect to a neighboring interval or the inverse of said change respectively; and

,

repeating said obtaining the signal, said detecting signal features, said determining the duration, said determining the change of duration and said generating graphical data for a plurality of heart cycles.

13. The method of claim 12, wherein said signal that represents periodically reoccurring events in the sequence of heart cycles is an electrocardiogram.

14. The method of claim 12, wherein said signal that represents periodically reoccurring events in the sequence of heart cycles is a marker signal comprising a marker that represents cardiac events.

15. The method of claim 12, further comprising:

detecting a cluster of data points in said scatter plot; and

, generating an output signal that depends on a location of one or more clusters of data points in said scatter plot.

16. The method of claim 12, further comprising:

comparing a location of one or more clusters of data points in said scatter plot to reference data; and

,

generating a rhythm classification output signal that depends on a similarity of a location of one or more clusters of data points in said scatter plot to said reference data.