Device for automatic mapping of complex fractionated atrial electrogram

Patent metadata

Field	Value
Publication number	US-9456759-B2
Application number	US-201414468267-A
Country	US
Kind code	B2
Filing date	Aug 25, 2014
Priority date	Sep 16, 2013
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A device that monitors and evaluates electrogram signals representing electric activities of a heart chamber, and includes a signal input connected to a mapping catheter, and a signal processing and evaluation unit. The mapping catheter includes one or more electrode poles that pick up electric potentials and generate electrogram signals therefrom. When an electrogram signal is received by the signal input, the signal processing and evaluation unit identifies waveform deflections in the electrogram signal, measures deflection intervals between each pair of consecutive deflection complexes in the electrogram signal, measures at least one metric that characterizes a morphology of a deflection complex in the electrogram signal, generates a multi-dimensional deflection vector of at least two dimensions for each identified deflection, determines a distance between each pair of consecutive deflections from the multi-dimensional deflection vectors, and determines a cumulative distance between deflections in a time window of predetermined length.

First claim

What is claimed is:

1. A device for monitoring and evaluating electrogram signals representing electric activities of a heart chamber, said device comprising:
a signal input connected to a mapping catheter, wherein the mapping catheter comprises at least one electrode pole that picks up electric potentials and generates electrogram signals from the picked up electric potentials, wherein said signal input receives the electrogram signals, and
a signal processing and evaluation unit that processes and evaluates the electrogram signals received at the signal input;
wherein when an electrogram signal is received by the signal input, the signal processing and evaluation unit
identifies waveform deflections in the electrogram signal,
measures deflection intervals between each pair of consecutive deflection complexes in the electrogram signal,
measures at least one metric that characterizes a morphology of a deflection complex in the electrogram signal,
generates a multi-dimensional deflection vector of at least two dimensions for each identified deflection using said at least one metric, wherein at least one element is the deflection interval,
determines a distance between each pair of consecutive deflections from the multi-dimensional deflection vectors, and
determines a cumulative distance between deflections in a time window of predetermined length;

wherein the device is connected to an ablation unit, wherein the ablation unit targets the electrode pole location with a highest determined cumulative distance from said determined cumulative distance between deflections to ablate the heart chamber, and,
wherein said device determines sites in the heart chamber that show complex fractionated atrial electrograms and wherein said ablation unit is configured to ablate the sites in the heart chamber that show complex fractioned atrial electrograms based on said highest determined cumulative distance.

2. The device according to claim 1 , wherein the signal processing and evaluation unit converts quasi non-discrete sampled values of preselected dimensions of the multi-dimensional deflection vector to discrete values, and determines a distance between each pair of consecutive deflections based on the converted discrete values of the multi-dimensional deflection vector.

3. The device according to claim 2 , wherein the signal processing and evaluation unit limits the converted discrete values of the multi-dimensional deflection vector to a predefined range with predetermined upper and lower interval thresholds, and bins the converted discrete values according to predefined bin width.

4. The device according to claim 1 , wherein the signal processing and evaluation unit processes electrogram signals in combination with position signals, wherein the position signals represent electrode poles location coordinates, and wherein each position signal is associated to at least one corresponding electrogram signal of the corresponding electrode pole.

5. The device according to claim 4 , wherein the signal processing and evaluation unit associates a location coordinate represented by the position signal to the determined distance between each pair of consecutive deflections.

6. The device according to claim 1 , wherein the device is connected to a display unit, wherein the display unit displays a distribution of said determined cumulative distances between deflections at different electrode pole locations in a reconstructed anatomical model of a heart chamber.

7. The device according to claim 1 , wherein the signal processing and evaluation unit performs the identification of waveform deflections through an adaptive threshold method, in which a deflection complex is detected when an amplitude of the electrogram signal crosses a threshold value which is adaptive to a previously detected deflection peak amplitude.

8. The device according to claim 1 , wherein said at least one metric that characterizes a morphology of a deflection complex in the electrogram signal measured by the signal processing and evaluation unit comprises a peak-to-peak amplitude.

9. The device according to claim 1 , wherein the signal processing and evaluation unit determines the distance between each pair of consecutive deflections using a weighted city block distance.

10. The device according to claim 1 , wherein the signal processing and evaluation unit continually evaluates electrogram signals received by the signal input.

11. The device according to claim 1 , wherein said at least one metric that characterizes a morphology of a deflection complex in the electrogram signal measured by the signal processing and evaluation unit comprises a metric extracted by a basis of a vector space.

12. The device according to claim 1 , wherein said at least one metric that characterizes a morphology of a deflection complex in the electrogram signal measured by the signal processing and evaluation unit comprises a metric which measures the complexity of the deflection complex.

13. The device according to claim 1 , wherein the signal processing and evaluation unit comprises
a deflection detection unit that identifies waveform deflections in the electrogram signal, a parameter measurement unit that measures deflection intervals between each pair of consecutive deflection complexes in the electrogram signal and measures at least one metric that characterizes the morphology of a deflection complex in the electrogram signal, and a parameter evaluation unit that
generates a multi-dimensional deflection vector of at least two dimensions for each identified deflection, wherein at least one element is the deflection interval,
determines a distance between each pair of consecutive deflections from the multi-dimensional deflection vectors, and
determines a cumulative distance between deflections in a time window of predetermined length.

Assignees

• Biotronik Se & Co Kg

Inventors

• Lian Jie
• S De Voir Christopher

Classifications

• A61B2018/00904

  Automatic detection of target tissue · CPC title

• A61B2018/00577

  Ablation · CPC title

• A61B2018/00839

  Bioelectrical parameters, e.g. ECG, EEG · CPC title

• A61B18/1492

  having a flexible, catheter-like structure, e.g. for heart ablation (A61B18/1477 takes precedence) · CPC title

• A61B34/20

  Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis · CPC title