Wearable cardioverter defibrillator (wcd) segment based episode opening and confirmation periods

Patent metadata

Field	Value
Publication number	US-2022143389-A1
Application number	US-202117546892-A
Country	US
Kind code	A1
Filing date	Dec 9, 2021
Priority date	Feb 14, 2018
Publication date	May 12, 2022
Grant date	—

Abstract

A wearable cardioverter defibrillator (WCD) comprises a plurality of electrocardiography (ECG) electrodes. An episode is opened responsive to a string of consecutive segments meeting one or more shock criteria, and a shockable rhythm is confirmed for the episode responsive to a subsequent string of consecutive segments meeting one or more confirmation criteria.

First claim

1 . A wearable cardioverter defibrillator (WCD), comprising:
a plurality of electrocardiogram (ECG) electrodes adapted to contact a patient's skin while the patient is wearing the WCD; a high voltage subsystem to provide a defibrillation voltage to the patient through a plurality of defibrillator electrodes in response to a shock signal; and one or more processors to receive ECG data via the plurality of ECG electrodes, wherein the one or more processors are configured to:
open an episode responsive to a string of consecutive segments of the ECG data meeting one or more shock criteria,
confirm a shockable rhythm in the episode responsive to a subsequent string of consecutive segments meeting one or more confirmation criteria,
initiate a patient alert sequence responsive to confirmation of a shockable rhythm, and
provide the shock signal responsive to completion of the patient alert sequence and not providing the shock signal responsive to a patient responding to the patient alert sequence.

2 . The WCD of claim 1 , wherein the one or more shock criteria comprises all segments in the string of consecutive segments being determined to indicate a shockable rhythm.

3 . The WCD of claim 1 , wherein the one or more shock criteria comprises a minimum number of segments in the string of consecutive segments being determined to indicate a shockable rhythm.

4 . The WCD of claim 3 , wherein the string of consecutive segments is six segments, and the minimum number of segments is five segments.

5 . The WCD of claim 1 , wherein the one or more confirmation criteria comprises all segments in the subsequent string of consecutive segments being determined to indicate a shockable rhythm.

6 . The WCD of claim 5 , wherein the shockable rhythm is VF and a number of segments in the subsequent string of consecutive segments is two.

7 . The WCD of claim 1 , wherein the one or more confirmation criteria comprises a minimum number of segments in the subsequent string of consecutive segments being determined to indicate a shockable rhythm.

8 . The WCD of claim 7 , wherein the shockable rhythm is VT and the string of consecutive segments is nineteen segments and the minimum number of segments is fifteen segments.

9 . The WCD of claim 1 , wherein the one or more processors are configured to determine whether a segment of the ECG data indicates a shockable rhythm based at least in part on a heart rate and a QRS width determined from the segment.

10 . The WCD of claim 1 , wherein the one or more processors are configured to classify a segment of the ECG data into one of a plurality of types based at least in part on a heart rate and a QRS width determined from the segment.

11 . The WCD of claim 10 , wherein the plurality of types comprises VF, VT, and SVT.

12 . The WCD of claim 11 , wherein a segment determined to have a heart rate above 120 beats per minute (BPM) and a QRS width less than 80 milliseconds (ms) is classified as SVT.

13 . A wearable medical system (WMS), comprising:
a support structure to be worn by a patient; a plurality of electrocardiogram (ECG) electrodes coupled to the support structure and structured to contact a patient's skin while the patient is wearing the support structure; and one or more processors to receive ECG data via the plurality of ECG electrodes, wherein the one or more processors are configured to:
open an episode responsive to a string of consecutive segments of the ECG data meeting one or more arrhythmia criteria,
determine an arrhythmia is confirmed in the episode in response to a subsequent string of consecutive segments meeting one or more confirmation criteria,
initiate a patient alert sequence responsive to a determination that the arrythmia is confirmed, and
not initiate the patient alert sequence responsive to a determination that the arrythmia is not confirmed.

14 . The WMS of claim 13 , wherein the one or more arrhythmia criteria comprises a minimum number of segments in the string of consecutive segments being determined to indicate the arrhythmia.

15 . The WMS of claim 14 , wherein the string of consecutive segments is six segments, and the minimum number of segments is five segments.

16 . The WMS of claim 13 , wherein the one or more confirmation criteria comprises a minimum number of segments in the subsequent string of consecutive segments being determined to indicate the arrhythmia.

17 . The WMS of claim 13 , wherein the one or more processors are configured to determine whether a segment of the ECG data indicates an arrhythmia based at least in part on a heart rate and a QRS width determined from the segment.

18 . The WMS of claim 13 , wherein the one or more processors are configured to classify a segment of the ECG data into one of a plurality of arrhythmias based at least in part on a heart rate and a QRS width determined from the segment.

19 . The WMS of claim 18 , wherein the plurality of arrhythmias comprises ventricular fibrillation (VF), ventricular tachycardia (VT), and supraventricular tachycardia (SVT).

20 . The WMS of claim 19 , wherein a segment determined to have a heart rate above 120 beats per minute (BPM) and a QRS width less than 80 milliseconds (ms) is classified as SVT.

Assignees

• West Affum Holdings Corp

Inventors

• Sullivan Joseph L
• Finch David P
• Medema Douglas K
• Buchanan Robert R
• Kotlarchik Garrett M
• Kim Jaeho
• Cowan Kenneth F

Classifications

• A61B2562/0215

  Silver or silver chloride containing · CPC title

• A61B2562/0214

  Capacitive electrodes · CPC title

• A61B5/7203

  for noise prevention, reduction or removal · CPC title

• A61B5/4836

  Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence) · CPC title

• A61B5/366

  Detecting abnormal QRS complex, e.g. widening · CPC title