Off-line sensing method and its applications in detecting undersensing, oversensing, and noise

• US 8,942,791 B2
• Filed: 05/30/2012
• Issued: 01/27/2015
• Est. Priority Date: 05/31/2011
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Dong, Yanting, Zhang, Shijie, Mahajan, Deepa, Liu, Chenguang, Li, Dan, Lin, Yayun, Bohn, Derek D.
• Primary Examiner(s): VOORHEES, CATHERINE M
• Application Number:
  US13/483,387
• Publication Number:
  US 20130138004A1
• Time in Patent Office: 972 Days
• Field of Search: 600/509, 600515-519, 600/521
• US Class Current: 600/509
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7217 of noise originating from a therapeutic or surgical apparatus, e.g. from a pacemaker
• CPC Class Codes: A61N 1/3704 Circuits specially adapted therefor, e.g. for sensitivity control
• CPC Class Codes: A61N 1/3937 Monitoring output parameters

Abstract

A system and method for performing independent, off-line evaluation of event sensing for collected electrograms, comprising: sensing an electrogram using an implantable medical device (IMD); determining locations of heart beats on at least one channel of the electrogram using a multi-pass process, resulting in a group of multi-pass beat locations; storing the electrogram and device-identified beat locations in a memory location; and retrieving the electrogram and device-identified beat locations from the memory location. The multi-pass process determines locations of heart beats on at least a first channel of the electrogram. The device-identified group of beat locations are then compared to the multi-pass group of beat locations identified using the multi-pass method. Based on the comparing step, oversensing of beats, undersensing of beats, or noise from the device can be detected.

Claims

1. A method for performing and evaluating independent, off-line event sensing for collected electrograms, comprising:

sensing an electrogram using an implantable medical device (IMD);

the IMD determining locations of heart beats within the electrogram, resulting in a group of device-identified beat locations for the electrogram;

storing the electrogram and device-identified beat locations in a memory location;

retrieving, by an external computing device, the electrogram and device-identified beat locations from the memory location;

after retrieving the electrogram from the memory location, determining, by the external computing device, locations of heart beats on at least a first channel of the electrogram using a multi-pass process, resulting in a group of multi-pass beat locations, wherein the multi-pass process comprises;

identifying a preliminary group of beat location candidates within the first channel of the electrogram;

eliminating a portion of the preliminary group of beat location candidates using a first algorithm resulting in a refined group of beat location candidates, wherein the first algorithm comprises comparing the amplitude of each of the preliminary beat location candidates with a first signal adaptive threshold; and

eliminating a portion of the refined group of beat location candidates using a second algorithm resulting in the group of multi-pass beat location candidates, wherein the second algorithm comprises comparing the amplitude of each of the preliminary beat location candidates with a second signal adaptive threshold; and

comparing the device-identified group of beat locations to the multi-pass group of beat locations identified using the multi-pass method.

2. The method of claim 1, wherein at least one of the first and second algorithms further comprises determining whether each of the preliminary beat location candidates is small noise.

3. The method of claim 1, wherein determining locations of heart beats is on at least the first channel and a second channel of the electrogram, wherein the first channel of the electrogram is an atrial channel and the second channel of the electrogram is a ventricular channel.

4. The method of claim 3, further comprising identifying oversensing of beats, undersensing of beats, or noise from the device based on the comparing of the device-identified group of beat locations to the multi-pass group of beat locations.