Method and apparatus for sensing cardiac contractile function

• US 20030105495A1
• Filed: 12/05/2001
• Published: 06/05/2003
• Est. Priority Date: 12/05/2001
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Yu, Yinghong, Zhu, Qingsheng, Ding, Jiang
• Granted Patent: US 6,980,866 B2
• Time in Patent Office: Days
• 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 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 2001/0585 Coronary sinus electrodes

Abstract

Systems and methods for detecting and measuring cardiac contractile function of a heart using an acceleration sensor unit inserted within the heart, such as within a vein of the cardiac wall are disclosed. The systems and methods involve detecting the occurrence of electrical events within the patient'"'"'s heart by inserting and positioning an implantable lead having an electrode near a cardiac wall as well as detecting mechanical events within the patient'"'"'s heart by then inserting and positioning a cardiac motion sensor unit through the inner lumen of the implantable lead. Furthermore, the systems and methods do not require dedicated leads and may be used with preexisting implantable leads.

Claims

1. A method of detecting and measuring cardiac contractile functions using a signal representative of cardiac wall motion provided by an acceleration sensor, said method comprising the steps of:

introducing said acceleration sensor unit into a vein of a cardiac wall;

positioning said acceleration sensor unit in said vein of said cardiac wall in a manner such that said acceleration sensor unit responds to movement of said cardiac wall and provides said signal representative of cardiac wall movement; and

connecting said acceleration sensor unit to an electronic device.

2. The method of claim 1, further comprising the step of removing said acceleration sensor from said vein of said cardiac wall.

3. The method of claim 1, wherein said vein of said cardiac wall is the coronary sinus vein.

4. The method of claim 1, wherein said electronic device is an implantable cardiac resynchronization device.

5. The method of claim 1, wherein the step of introducing said acceleration sensor unit into said vein of said cardiac wall comprises the steps of introducing an implantable lead into said vein of said cardiac wall and inserting said acceleration sensor unit along an inner lumen of said implantable lead.

6. The method of claim 5, further comprises the step of removing said acceleration sensor from said vein of said cardiac wall.

7. A method of detecting and measuring cardiac contractile functions of a heart using a signal representative of cardiac wall motion provided by an acceleration sensor, said method comprising the steps of:

inserting a guide element along an inner lumen of an implantable lead;

introducing said implantable lead into said heart;

positioning said implantable lead within said heart using said guide element;

removing said guide element from said inner lumen of said implantable lead; and

subsequent to removing said guide element, inserting said acceleration sensor unit along said inner lumen of said implantable lead.

8. The method of claim 7, further comprising the step of removing said acceleration sensor from said inner lumen of said implantable lead.

9. The method of claim 7, further comprising the step of connecting said implantable lead and said acceleration sensor unit to an electronic device.

10. The method of claim 7, wherein said implantable lead includes one or more electrodes.

11. The method of claim 10, wherein said acceleration sensor unit is disposed adjacent to said electrodes.

12. The method of claim 7, wherein said implantable lead is positioned within a vein of a cardiac wall of said heart.

13. The method of claim 7, wherein said implantable lead is directly attached to a cardiac wall of said heart.

21. The method of claim 13, wherein prior to inserting said cardiac motion sensor along said inner lumen of said implantable lead, said method further comprising the step of attaching the implantable lead directly to a cardiac wall.

14. A method of creating a sensor for detecting and measuring cardiac contractile function, said method comprising the steps of:

inserting a cardiac motion sensor along an inner lumen of an implantable lead; and

positioning said cardiac motion sensor within said inner lumen of said implantable lead such that said cardiac motion sensor remains mobile relative to the longitudinal axis of said implantable lead.

15. The method of claim 14, further comprising the step of removing said cardiac motion sensor from said inner lumen of said implantable lead.

16. The method of claim 14, wherein said cardiac motion sensor comprises an accelerometer.

17. The method of claim 14, wherein prior to inserting said cardiac motion sensor along said inner lumen of said implantable lead, said method further comprises the steps of:

connecting a conductor to said cardiac motion sensor;

passing said conductor through said inner lumen of said imp lantable lead; and

connecting said conductor to an electrical device such that said conductor fixes said cardiac motion sensor relative to the longitudinal axis of said lead.

18. The method of claim 17, further comprising the step of removing said cardiac motion sensor from said inner lumen of said implantable lead.

19. The method of claim 14, wherein prior to inserting said cardiac motion sensor along said inner lumen of said implantable lead, said method further comprises the steps of:

inserting a guide element along the inner lumen of said implantable lead;

introducing said implantable lead into a vein of a cardiac wall;

positioning said implantable lead within said vein using said guide element; and

removing said guide element from said inner lumen of said implantable lead.

20. The method of claim 18, further comprising the step of removing said cardiac motion sensor from said inner lumen of said implantable lead.

22. A cardiac motion sensor unit comprising:

an acceleration sensing device that generates a signal representative of movement of a cardiac wall when the acceleration sensing device is disposed at the cardiac wall;

a conductor device molded into an elongated insulator body that transmits said signal representative of movement of said cardiac wall from said acceleration sensing device to an electronic device; and

a connector device that electrically links said conductor device to said electronic device.

23. The cardiac motion sensor unit of claim 22, wherein said acceleration sensing device is disposed within a vein of said cardiac wall.

24. The cardiac motion sensor unit of claim 22, wherein said acceleration sensing device comprises an accelerometer.

25. The cardiac motion sensor unit of claim 22, wherein said conductor device comprises two electrical conductors molded into an elongated insulator body that transmits said signal representative of said cardiac wall accelerations to said electronic device.

26. The cardiac motion sensor unit of claim 22, wherein said elongated insulator body comprises a polymer.

27. The cardiac motion sensor unit of claim 22, wherein said acceleration sensing device is disposed within an inner lumen of a cylindrical lead.

28. The cardiac motion sensor unit of claim 27, wherein said cylindrical lead comprises a conductive means for sensing cardiac electrical activity and delivering stimulation to said cardiac wall.

29. The cardiac motion sensor unit of claim 28, further comprising a second cylindrical lead with conductive means for sensing cardiac electrical activity and delivering stimulation to said cardiac wall, said second cylindrical lead concentrically encompassing said cylindrical lead.

30. The cardiac motion sensor unit of claim 29, wherein said cylindrical lead and said second cylindrical lead further comprise a coiled electrically conductive material.

31. The cardiac motion sensor unit of claim 29, wherein said cardiac motion sensor unit further comprises an electrode device for delivering electric stimulation to said cardiac wall.

32. A cardiac motion sensor unit comprising:

acceleration sensing means for providing a signal representative of a cardiac wall movement when disposed at the cardiac wall;

conductor means molded into an elongated insulator body for transmitting said signal representative of movement of said cardiac wall from said acceleration sensing means to an electronic sensing means; and

connector means for electrically linking said conductor means to said electronic sensing means.

33. The cardiac motion sensor unit of claim 32, wherein said acceleration sensing means is disposed within a vein of said cardiac wall.

34. The cardiac motion sensor unit of claim 32, wherein said cardiac wall acceleration sensing means comprises an accelerometer.

35. The cardiac motion sensor unit of claim 32, wherein said conductor means comprises two electrical conductor means molded into an insulate elongate body for transmitting said signal representative of said cardiac wall movement to said electronic sensing means.

36. The cardiac motion sensor unit of claim 32, wherein said insulator comprises a polymer.

37. The cardiac motion sensor unit of claim 32, wherein said acceleration sensing means is disposed within an inner lumen of a cylindrical lead.

38. The cardiac motion sensor unit of claim 37, wherein said cylindrical lead comprises a conductive means for sensing cardiac electrical activity and delivering stimulation to said cardiac wall.

39. The cardiac motion sensor unit of claim 38, further comprising a second cylindrical lead with conductive means for sensing cardiac electrical activity and delivering stimulation to said cardiac wall, said second cylindrical lead concentrically encompassing said cylindrical lead.

40. The cardiac motion sensor unit of claim 39, wherein said cylindrical lead and said second cylindrical lead further comprise a coiled electrically conductive material.