Method and apparatus for arrhythmia classification using atrial signal mapping

• US 8,768,444 B2
• Filed: 11/01/2011
• Issued: 07/01/2014
• Est. Priority Date: 11/30/2004
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhang, Yunlong, Thompson, Julie A., Gilkerson, James O., Zhang, Yongxing
• Primary Examiner(s): Gedeon, Brian T
• Application Number:
  US13/286,435
• Publication Number:
  US 20120046565A1
• Time in Patent Office: 973 Days
• Field of Search: None
• US Class Current: 600/515
• 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 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

An implantable medical device senses a plurality of electrograms from substantially different atrial locations, detects regional depolarizations from the electrograms, and analyzes timing relationships among the regional depolarizations. The timing relationships provide a basis for effective therapy control and/or prognosis of certain cardiac disorders. In one embodiment, an atrial activation sequence is mapped to show the order of occurrences of the regional depolarizations during an atrial depolarization for classifying a detected tachyarrhythmia by its origin. In another embodiment, conduction time between two atrial locations is measured for monitoring the development of an abnormal atrial conditions and/or the effect of a therapy.

Claims

1. An implantable medical device for coupling to a heart having a right atrium (RA), a left atrium (LA), a sinoatrial (SA) node, and an atrial septum through one or more leads including a first electrode for placement near the SA node, a second electrode for placement near the atrial septum, and a third electrode for placement in the LA, the implantable medical device comprising:

a sensing circuit configured to sense a plurality of atrial electrograms using the plurality of atrial electrodes;

an arrhythmia detection circuit configured to detect tachyarrhythmia; and

an arrhythmia classification circuit configured to classify the detected tachyarrhythmia, the arrhythmia classification circuit including;

an atrial signal mapping module configured to map an atrial activation sequence using the sensed plurality of atrial electrograms, the atrial activation sequence indicative of an order of regional depolarizations during an atrial depolarization; and

an atrial pattern analyzer configured to classify the detected tachyarrhythmia using the atrial activation sequence.

2. The implantable medical device of claim 1, wherein the sensing circuit is configured to sense an RA electrogram through the first electrode, an LA electrogram through the third electrode, and an atrial septal electrogram through the second electrode, and the atrial signal mapping module is configured to map an atrial activation sequence using the RA electrogram, the LA electrogram, and the atrial septal electrogram.

3. The implantable medical device of claim 2, further comprising:

an event detection circuit configured to detect an RA event from the RA electrogram and an LA event from the LA electrogram during an atrial depolarization;

an inter-atrial interval measurement circuit configured to measure an inter-aerial interval being a time interval between the RA event and the LA event; and

one or more of an atrial enlargement detection circuit and an atrial conduction disturbance detection circuit, the atrial enlargement detection circuit configured to detect abnormal enlargement of at least one of the RA and LA using the inter-atrial interval, the atrial conduction disturbance detection circuit configured to detect atrial conduction disturbance using the inter-atrial interval.

4. The implantable medical device of claim 3, further comprising the atrial enlargement detection circuit, and the atrial enlargement detection circuit comprises a comparator including a first input to receive the inter-atrial interval, a second input to receive a predetermined threshold interval, and an output to indicate the abnormal enlargement of at least one atrium when the inter-atrial interval exceeds the predetermined threshold interval.

5. The implantable medical device of claim 3, further comprising the atrial conduction disturbance detection circuit, and the atrial conduction disturbance detection circuit is configured to detect a variance of the inter-atrial interval and comprises a comparator including a first input to receive the variance of the inter-atrial interval, a second input to receive a predetermined threshold variance, and an output to indicate the atrial conduction disturbance when the variance of the inter-atrial interval exceeds the predetermined threshold variance.

6. The implantable medical device of claim 1, wherein the atrial pattern analyzer comprises at least two of:

a right atrial pattern matching module configured to detect a supraventricular tachyarrhythmia of a right atrial origin by comparing the atrial activation sequence to a predetermined right atrial pattern template sequence;

a left atrial pattern matching module configured to detect an supraventricular tachyarrhythmia of a left atrial origin by comparing the atrial activation sequence to a predetermined left atrial pattern template sequence; and

an atrial septal pattern matching module configured to detect one of a supraventricular tachyarrhythmia of atrial septal origin and a ventricular tachyarrhythmia by comparing the atrial activation sequence to a predetermined atrial septal pattern template sequence.

7. A cardiac rhythm management system coupled to a heart having a right atrium (RA) connected to a superior vena cava, a left atrium (LA), a left ventricle (LV), a sinoatrial (SA) node, an atrial septum, a coronary sinus, and a coronary vein, the system comprising:

one or more leads including a plurality of atrial electrodes; and

an implantable medical device coupled to the one or more leads, the implantable medical device including;

a sensing circuit configured to sense a plurality of atrial electrograms using the plurality of atrial electrodes;

an arrhythmia detection circuit configured to detect tachyarrhythmia; and

an arrhythmia classification circuit configured to classify the detected tachyarrhythmia, the arrhythmia classification circuit including;

an atrial signal mapping module configured to map an atrial activation sequence using the sensed plurality of atrial electrograms, the atrial activation sequence indicative of an order of regional depolarization during an atrial depolarization; and

an atrial pattern analyzer configured to classify the detected tachyarrhythmia using the atrial activation sequence.

8. The system of claim 7, wherein the one or more leads comprises a first lead including:

an LA electrode configured for placement in the coronary sinus or coronary vein near the LA;

an atrial septal electrode configured for placement in the coronary sinus near the atrial septum; and

a high RA (HRA) electrode configured for placement in the RA or the superior vena cava near the SA node,

wherein the sensing circuit is configured to sense an RA electrogram via the HRA electrode, an LA electrogram via the LA electrode, and an atrial septal electrogram via the atrial septal electrode, and wherein the atrial signal mapping module is configured to map an atrial activation sequence using the RA electrogram, the LA electrogram, and the atrial septal electrogram.

9. The system of claim 8, wherein the implantable medical device comprises:

an event detection circuit configured to detect an RA event from the RA electrogram and an LA event from the LA electrogram during an atrial depolarization; and

an inter-atrial interval measurement circuit configured to measure an inter-atrial interval being a time interval between the RA event and the LA event.

10. The system of claim 9, wherein the implantable medical device further comprises one or more of an atrial enlargement detection circuit and an atrial conduction disturbance detection circuit, the atrial enlargement detection circuit configured to detect abnormal enlargement of at least one of the RA and LA using the inter-atrial interval, the atrial conduction disturbance detection circuit configured to detect atrial conduction disturbance using the inter-atrial interval.

11. The system of claim 10, wherein the implantable medical device comprises the atrial enlargement detection circuit, and the atrial enlargement detection circuit comprises a comparator including a first input to receive the inter-atrial interval, a second input to receive a predetermined threshold interval, and an output to indicate the abnormal enlargement of at least one atrium when the inter-atrial interval exceeds the predetermined threshold interval.

12. The system of claim 10, wherein the implantable medical device comprises the atrial conduction disturbance detection circuit, and the atrial conduction disturbance detection circuit is configured to detect a variance of the inter-atrial interval and comprises a comparator including a first input to receive the variance of the inter-atrial interval, a second input to receive a predetermined threshold variance, and an output to indicate the atrial conduction disturbance when the variance of the inter-atrial interval exceeds the predetermined threshold variance.

13. The system of claim 8, wherein the first lead further comprises an LV electrode configured for placement in the coronary vein over the LV, the sensing circuit is further configured to sense an LV electrogram via the LV electrode, and the atrial pattern analyzer is configured to classify the tachyarrhythmia using the atrial activation sequence and the LV electrogram.

14. The system of claim 9, wherein the one or more leads comprises a first lead and a second lead, the first lead including a high RA (HRA) electrode configured for placement in the RA or the superior vena cava near the SA node and a second RA electrode configured for placement in the RA, the second lead including an LA electrode configured for placement in the coronary sinus or coronary vein near the LA, wherein the sensing circuit is configured to sense an RA electrogram via the HRA electrode, an LA electrogram via the LA electrode, and an atrial septal electrogram via the second atrial electrode, and wherein the atrial signal mapping module is configured to map an atrial activation sequence using the RA electrogram, the LA electrogram, and the atrial septal electrogram.

15. The system of claim 14, wherein the implantable medical device further comprises:

an event detection circuit configured to detect an RA event from the RA electrogram and an LA event from the LA electrogram during an atrial depolarization; and

an inter-atrial interval measurement circuit configured to measure a time interval between the RA event and the LA event.

16. The system of claim 15, wherein the implantable medical device further comprises one or more of an atrial enlargement detection circuit and an atrial conduction disturbance detection circuit, the atrial enlargement detection circuit configured to detect abnormal enlargement of at least one atrium using the inter-atrial interval, the atrial conduction disturbance detection circuit configured to detect atrial conduction disturbance using the inter-atrial interval.

17. The system of claim 16, wherein the implantable medical device comprises the atrial enlargement detection circuit, and the atrial enlargement detection circuit comprises a comparator including a first input to receive the inter-atrial interval, a second input to receive a predetermined threshold interval, and an output to indicate the abnormal enlargement of at least one atrium when the inter-atrial interval exceeds the predetermined threshold interval.

18. The system of claim 16, wherein the implantable medical device comprises the atrial conduction disturbance detection circuit, and the atrial conduction disturbance detection circuit is configured to detect a variance of the inter-atrial interval and comprises a comparator including a first input to receive the variance of the inter-atrial interval, a second input to receive a predetermined threshold variance, and an output to indicate the atrial conduction disturbance when the variance of the inter-atrial interval exceeds the predetermined threshold variance.

19. The system of claim 14, wherein the second lead further comprises an LV electrode configured for placement in the coronary vein over the LV, wherein the sensing circuit is further configured to sense an LV electrogram via the LV electrode, and wherein the atrial pattern analyzer is configured to classify the tachyarrhythmia using the atrial activation sequence and the LV electrogram.

20. The system of claim 7, wherein the atrial pattern analyzer comprises at least two of:

a right atrial pattern matching module configured to detect a supraventricular tachyarrhythmia of a right atrial origin by comparing the atrial activation sequence to a predetermined right atrial pattern template sequence;

a left atrial pattern matching module configured to detect an supraventricular tachyarrhythmia of a left atrial origin by comparing the atrial activation sequence to a predetermined left atrial pattern template sequence; and

an atrial septal pattern matching module configured to detect one of a supraventricular tachyarrhythmia of atrial septal origin and a ventricular tachyarrhythmia by comparing the atrial activation sequence to a predetermined atrial septal pattern template sequence.