Methods and arrangements for reducing oversensing and/or providing diagnostic information in implantable medical devices
First Claim
Patent Images
1. A method comprising:
- sensing, in vivo, a first waveform cycle corresponding to electrical cardiac activity, the first waveform cycle comprising a first portion and a second portion subsequent the first portion;
comparing the amplitude of the first portion of the first cycle to a low sensitivity threshold;
if the comparing indicates that the amplitude of the first portion of the first cycle does not meet or exceed the low sensitivity threshold then further comparing the amplitude of the second portion of the first cycle to a high sensitivity threshold;
if the further comparing indicates that the amplitude of the second portion of the first cycle meets or exceeds the high sensitivity threshold then determining that ventricular fibrillation may exist;
if ventricular fibrillation may exist, delivering a ventricular pacing pulse;
detecting for an evoked response; and
if an evoked response is detected, determining that ventricular fibrillation does not exist;
terminating delivery of ventricular pacing pulses;
sensing, in vivo, a subsequent waveform cycle corresponding to electrical cardiac activity, the subsequent waveform cycle comprising a first portion and a second portion subsequent the first portion;
comparing the amplitude of the first portion to the low sensitivity threshold; and
if the comparing indicates that the amplitude of the first portion meets or exceeds the low sensitivity threshold, confirming that ventricular fibrillation does not exist.
1 Assignment
0 Petitions
Accused Products
Abstract
An exemplary method to reduce risk of ventricular oversensing includes sensing, in vivo, amplitude of electrical cardiac activity, comparing sensed amplitude to a low sensitivity threshold where if the comparing indicates that sensed amplitude does not meet or exceed the low sensitivity threshold then further comparing the sensed amplitude to a high sensitivity threshold and if the further comparing indicates that sensed amplitude meets or exceeds the high sensitivity threshold then determining that ventricular fibrillation may exist. Various exemplary devices, systems, methods, etc., are disclosed.
-
Citations
9 Claims
-
1. A method comprising:
-
sensing, in vivo, a first waveform cycle corresponding to electrical cardiac activity, the first waveform cycle comprising a first portion and a second portion subsequent the first portion; comparing the amplitude of the first portion of the first cycle to a low sensitivity threshold; if the comparing indicates that the amplitude of the first portion of the first cycle does not meet or exceed the low sensitivity threshold then further comparing the amplitude of the second portion of the first cycle to a high sensitivity threshold; if the further comparing indicates that the amplitude of the second portion of the first cycle meets or exceeds the high sensitivity threshold then determining that ventricular fibrillation may exist; if ventricular fibrillation may exist, delivering a ventricular pacing pulse; detecting for an evoked response; and if an evoked response is detected, determining that ventricular fibrillation does not exist;
terminating delivery of ventricular pacing pulses;
sensing, in vivo, a subsequent waveform cycle corresponding to electrical cardiac activity, the subsequent waveform cycle comprising a first portion and a second portion subsequent the first portion;
comparing the amplitude of the first portion to the low sensitivity threshold; and
if the comparing indicates that the amplitude of the first portion meets or exceeds the low sensitivity threshold, confirming that ventricular fibrillation does not exist. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An implantable medical device comprising:
-
means for sensing, in vivo, a first waveform cycle corresponding to electrical cardiac activity, the first waveform cycle comprising a first portion and a second portion subsequent the first portion; means for comparing the amplitude of the first portion of the first cycle to a low sensitivity threshold; means for further comparing the amplitude of the second portion of the first cycle to a high sensitivity threshold if the comparing to the low sensitivity threshold indicates that the amplitude of the first portion of the first cycle does not meet or exceed the low sensitivity threshold then further; means for determining that ventricular fibrillation may exist if the further comparing indicates that the amplitude of the second portion of the first cycle meets or exceeds the high sensitivity threshold; means for delivering a ventricular pacing pulse if ventricular fibrillation may exist; means for detecting for an evoked response; and means for, if an evoked response is detected, determining that ventricular fibrillation does not exist;
terminating delivery of ventricular pacing pulses;
sensing, in vivo, a subsequent waveform cycle corresponding to electrical cardiac activity, the subsequent waveform cycle comprising a first portion and a second portion subsequent the first portion;
comparing the amplitude of the first portion to the low sensitivity threshold; and
if the comparing indicates that the amplitude of the first portion meets or exceeds the low sensitivity threshold, confirming that ventricular fibrillation does not exist.
-
Specification