Cardiac pacing using adjustable atrio-ventricular delays

• US 8,103,345 B2
• Filed: 11/29/2010
• Issued: 01/24/2012
• Est. Priority Date: 05/08/1998
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Ding, Jiang, Yu, Yinghong, Kramer, Andrew P., Spinelli, Julio C.
• Primary Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US12/955,218
• Publication Number:
  US 20110071588A1
• Time in Patent Office: 421 Days
• Field of Search: 607/9, 607 17- 19, 607 23- 25
• US Class Current: 607/17
• 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 1/3682 with a variable atrioventricular delay
• CPC Class Codes: E21B 17/01 Risers

Abstract

A pacing system for providing optimal hemodynamic cardiac function for parameters such as contractility (peak left ventricle pressure change during systole or LV+dp/dt), or stroke volume (aortic pulse pressure) using system for calculating atrio-ventricular delays for optimal timing of a ventricular pacing pulse. The system providing an option for near optimal pacing of multiple hemodynamic parameters. The system deriving the proper timing using electrical or mechanical events having a predictable relationship with an optimal ventricular pacing timing signal.

Claims

1. A method, comprising:

detecting an atrial electrical event P;

detecting a ventricular mechanical event Y;

measuring a time interval PY between the atrial electrical event P and the ventricular mechanical event Y;

determining an optimal atrio-ventricular delay time interval (AVD_c) which is approximately optimized to provide a maximum increase in left ventricular pressure (LV+dp/dt) using the time interval PY and a predetermined mapping of a relationship between the time interval PY and the optimal AVD_c; and

delivering a ventricular pacing pulse with the optimal AVD_c.

2. The method of claim 1, further comprising:

determining a model which approximates the optimal AVD_c to provide the AVD_c; and

delivering the ventricular pacing pulse to maximize the LV+dp/dt using the AVD_c.

3. The method of claim 2, comprising:

performing a linear regression between the time interval PY and the optimal AVD_c; and

delivering the pacing pulse using the AVD_c which is provided by M1·

PY−

M2, where M1 and M2 are coefficients of the linear regression.

4. The method of claim 3, wherein the ventricular pacing pulse is delivered to a left ventricle, wherein the time interval PY is measured from a right atrial sensing marker, P, to a beginning of intrinsic LV pressure development, Y, which corresponds to the beginning of LV systole.

5. The method of claim 4, wherein M1 is approximately 0.96 milliseconds, and M2 is approximately 139 milliseconds.

6. The method of claim 2, further comprising:

measuring the time difference, N, between the time interval PY and the optimal AVD_c;

averaging the time difference N over a patient population; and

delivering the pacing pulse using the AVD_c which is provided by PY−

N_a, where N_a is the averaged time difference N.

7. The method of claim 6, wherein the ventricular pacing pulse is delivered to a left ventricle, wherein the time interval PY is measured from a right atrial sensing marker, P, to the beginning of intrinsic LV pressure development, Y, which corresponds to the beginning of LV systole.

8. The method of claim 6, wherein N_a is approximately 150 milliseconds.

9. The method of claim 2, wherein the ventricular mechanical event Y includes a signal from a cardiac phonogram signaling an onset of ventricular pressure during systole.

10. The method of claim 2, wherein the ventricular mechanical event Y includes a signal from an accelerometer signaling an onset of ventricular pressure during systole.

11. The method of claim 2, wherein the ventricular mechanical event Y includes a signal from a Doppler recording signaling an onset of ventricular pressure during systole.

12. The method of claim 2, wherein the ventricular mechanical event Y includes a signal from an echo imager signaling an onset of ventricular pressure during systole.

13. An apparatus, comprising:

a programmable pulse generator having a mechanical event sensor adapted to monitor a signal representing ventricular mechanical activity including a ventricular mechanical event Y and an electrical event sensor adapted to monitor a signal representing atrial electrical activity including an atrial electrical event P, wherein the programmable pulse generator is adapted to measure a time interval PY between the atrial electrical event P and the ventricular mechanical event Y, determine an optimal atrio-ventricular delay time interval (AVD_c) which is approximately optimized to provide a maximum increase in left ventricular pressure (LV+dp/dt) using the time interval PY and a predetermined mapping of a relationship between the time interval PY and the optimal AVD_c, and deliver a ventricular pacing pulse with the optimal AVD_c.

14. The apparatus of claim 13, wherein the programmable pulse generator is adapted to calculates AVD_c using a linear equation AVD_c=M1·

PY−

M2, where M1 and M2 are constants.

15. The apparatus of claim 14, wherein M1 is approximately 0.96 milliseconds, and M2 is approximately 139 milliseconds.

16. The apparatus of claim 13, wherein the programmable pulse generator is adapted to calculate AVD_c using a linear equation AVD_c=PY−

N_a.

17. The apparatus of claim 16, wherein N_a is approximately 150 milliseconds.

18. The apparatus of claim 13, wherein the programmable pulse generator is adapted to measure the time interval PY from a right atrial sensing marker (P) to a beginning of intrinsic LV pressure development (Y) which corresponds to a beginning of LV systole, and deliver the ventricular pacing pulse to a left ventricle.

19. The apparatus of claim 18, wherein the mechanical event sensor comprises a pressure transducer.

20. The apparatus of claim 18, wherein the mechanical event sensor comprises an accelerometer.