Monitoring for mitral valve regurgitation

• US 7,848,793 B1
• Filed: 09/29/2006
• Issued: 12/07/2010
• Est. Priority Date: 09/29/2006
• Status: Expired due to Fees

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Paris, Michael, Shelchuk, Anne M.
• Primary Examiner(s): Bockelman; Mark W
• Assistant Examiner(s): Dinga; Roland
• Application Number:
  US11/537,322
• Time in Patent Office: 1,530 Days
• Field of Search: 600/509, 600/513, 600/508, 607/18, 607/23
• US Class Current: 600/509
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371

Abstract

Implantable systems, and methods for use therein, for monitoring for mitral valve regurgitation (MR) are provided. An electrogram (EGM) signal and a corresponding pressure signal are obtained, where the EGM signal is representative of electrical functioning of the patient'"'"'s heart during a plurality of cardiac cycles, and the corresponding pressure signal is representative of pressure within the left atrium the patient'"'"'s heart during the cardiac cycles. Windows of the pressure signal are defined, based on events detected in the EGM signal, and measurements from the windows are used to monitor for MR.

Claims

1. In an implantable system, a method for monitoring a patient'"'"'s heart for mitral valve regurgitation (MR), comprising:

(a) obtaining an electrogram (EGM) signal and a corresponding pressure signal, the EGM signal representative of electrical functioning of the patient'"'"'s heart during a plurality of cardiac cycles, the corresponding pressure signal representative of pressure within the left atrium the patient'"'"'s heart during the cardiac cycles;

(b) for each of a plurality of cardiac cycles represented in the EGM and pressure signals,

(b.1) determining a maximum peak within a first window of the pressure signal,

wherein a start of the first window is defined relative to an event detected in the EGM signal, and

wherein a length of the first window is defined to include at least one of an a-wave and a c-wave, but not a v-wave, of the cardiac cycle represented in the pressure signal; and

(b.2) determining a maximum peak within a second window of the pressure signal,

wherein a start of the second window is defined relative to an event detected in the EGM signal or relative to the first window, and

wherein a length of the second window is defined to include the v-wave of the cardiac cycle represented in the pressure signal;

(c) comparing the maximum peak detected within one or more said first window to the maximum peak detected within one or more said second window; and

(d) monitoring for MR based on results of the comparing.

2. The method of claim 1, wherein:

step (c) includes determining a ratio based on the maximum peak detected within one or more said first window and the maximum peak detected within one or more said second window, or vice versa; and

step (d) includes detecting MR by comparing the ratio to a threshold.

3. The method of claim 1, wherein:

step (c) includes determining a difference between the maximum peak detected within one or more said first window and the maximum peak detected within one or more said second window; and

step (d) includes detecting MR when the difference exceeds a threshold.

4. An implantable system for monitoring a patient'"'"'s heart for mitral valve regurgitation (MR), comprising:

one or more electrode to obtain an electrogram (EGM) signal representative of electrical functioning of the patient'"'"'s heart during a plurality of cardiac cycles;

one or more sensor to obtain a corresponding pressure signal representative of pressure within the left atrium the patient'"'"'s heart during the cardiac cycles; and

one or more processor to determine, for each of a plurality of cardiac cycles represented in the EGM and pressure signals,

a maximum peak within of a first window of the pressure signal, wherein a start of the first window is defined relative to an event detected in the EGM signal, and wherein a length of the first window is defined to include at least one of an a-wave and a c-wave, but not a v-wave, of the cardiac cycle represented in the pressure signal; and

a maximum peak within a second window of the pressure signal, wherein a start of the second window is defined relative to an event detected in the EGM signal or relative to the first window, and wherein a length of the second window is defined to include the v-wave of the cardiac cycle represented in the pressure signal;

wherein the one or more processor monitors for MR based on comparisons of the maximum peak detected within one or more said first window to the maximum peak detected within one or more said second window.

5. The system of claim 4, wherein the one or more processor:

determines a ratio based on the maximum peak detected within one or more said first window and the maximum peak detected within one or more said second window, or vice versa; and

detects MR by comparing the ratio to a threshold.

6. The system of claim 4, wherein the one or more processor:

determines a difference between the maximum peak detected within one or more said first window and the maximum peak detected within one or more said second window; and

detects MR when the difference exceeds a threshold.