Biocompatible ventricular assist and arrhythmia control device including cardiac compression pad and compression assembly

• US 5,098,369 A
• Filed: 05/14/1990
• Issued: 03/24/1992
• Est. Priority Date: 02/27/1987
• Status: Expired due to Fees

• Current Assignee: Vascor, Inc.
• Original Assignee: Vascor, Inc.
• Inventors: Capone, Christopher D., Prem, Edward K., Heilman, Marlin S., Parisi, Carl M., Kolenik, Steve A., Speicher, Vernon L.
• Primary Examiner(s): Jaworski, Francis
• Assistant Examiner(s): MANUEL, GEORGE C
• Application Number:
  US07/522,956
• Time in Patent Office: 680 Days
• Field of Search: 600/15, 600/16, 600/17, 623/3, 128/419 D, 128/30.2
• US Class Current: 600/16
• CPC Class Codes: A61M 60/191 mechanically acting upon the outside of the patient's native heart, e.g. compressive structures placed around the heart
• CPC Class Codes: A61M 60/289 Devices for mechanical circulatory actuation assisting the residual heart function by means mechanically acting upon the patient's native heart or blood vessel structure, e.g. direct cardiac compression [DCC] devices
• CPC Class Codes: A61M 60/468 the force acting on the actuation means being hydraulic or pneumatic
• CPC Class Codes: A61M 60/476 with means converting the rotation into a translational movement of the displacement member
• CPC Class Codes: A61M 60/861 Connections or anchorings for connecting or anchoring pumps or pumping devices to parts of the patient's body
• CPC Class Codes: A61M 60/878 Electrical connections within the patient's body
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy

Abstract

A ventricular assist device may include a cardiac compression assembly which comprises a gel-filled pad of generally concave configuration, mounted on a pressure plate with peripheral portions of the pad extending beyond the periphery of the plate, to preclude damage to the heart by the peripheral edges of the plate. The gel-filled pad may have undulating opposite sides formed by intersecting rows of raised dimples. The pad also includes portions for suturing the pad to a heart ventricle, and at least some of the dimples on the side of the pad facing the heart ventricle are provided with ventricle tissue growth-promoting islands. An electrode, in the form of a grid having intersecting strips which define dimple-receiving openings therebetween, also may be mounted on the venticle side of the pad. As many as eight circumferentially arranged cardiac compression assemblies, having lower ends pivotally mounted on a support member adapted to be located adjacent the apex of a heart ventricle, may be provided. Operating systems for operating the cardiac compression assemblies may include a motor-driven camming mechanism; a mechanism comprising a device for converting electrical energy to hydraulic fluid energy, two sealed fluid systems, a reversible pump, two bellows and a safety solenoid pump-bypass fluid return valve; or a closed loop system comprising a reversible pump in a fluid supply casing, a hydraulic fluid manifold including a plurality of miniature fluid actuators which may be of arcuate construction to conserve space, and a mechanism for collecting fluid leaking from the actuators and returning it to the fluid supply casing.

Claims

1. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes one or more movable ventricle compression assemblies;

gel-filled pad means forming respective parts of the one or more movable ventricle compression assemblies, said gel-filled pad means being adapted for engaging an outer surface of at least one heart ventricle; and

operating means for cyclically actuating the one or more ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling.

2. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means has a generally concave configuration so as to be adapted to conform to the heart ventricle.

3. The ventricular assist device as recited in claim 1, in which each ventricle compression assembly includes a pivotable pressure plate connected to the operating means and having an outer periphery, each of the gel-filled pad means being mounted on a respective one of the plates and extending beyond the outer periphery of the plate.

4. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means includes means which is adapted for gluing and/or suturing the respective compression assembly to the heart ventricle.

5. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means includes a hollow sheath formed of soft, electrically insulating material.

6. The ventricular assist device as recited in claim 5, in which the soft, electrically insulating material of the sheath has a specific gravity and stiffness similar to that of human muscle tissue so as to be adapted to be easily deformed.

7. The ventricular assist device as recited in claim 6, in which the material of the sheath is a polyurethane elastomer.

8. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means is filled with a soft gel having the characteristics of polyurethane or silicone.

9. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means has an undulating surface formed by a series of multiple raised portions adapted to engage the heart ventricle so as to shrink and expand with the ventricle.

10. The ventricular assist device as recited in claim 9, in which the raised portions of the undulating surface are intersecting rows of raised dimples.

11. The ventricular assist device as recited in claim 10, in which at least one of the gel-filled pad means includes electrode means for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle.

12. The ventricular assist device as recited in claim 11, in which the electrode means is mounted in depressed portions of the undulating surface of the at least one gel-filled pad means between selected ones of the raised dimples.

13. The ventricular assist device as recited in claim 12, in which the electrode means is in the form of a grid having intersecting strip portions which define dimple-receiving openings therebetween.

14. The ventricular assist device as recited in claim 9, in which selected ones of the raised portions include surface portion means adapted to promote ventricle tissue growth to the gel-filled pad means.

15. The ventricular assist device as recited in claim 14, in which the tissue growth-promoting surface portion means are formed of DACRON (polyester).

16. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means has opposite sides each having an undulating surface formed by a series of multiple raised portions.

17. The ventricular assist device as recited in claim 16, in which each of the raised portions of the undulating surfaces are intersecting rows of raised dimples, with selected ones of the dimples on one side of the gel-filled pad means being bonded to a respective one of the pressure plates and selected ones of the dimples on the other side of the gel-filled pad means being adapted to be bonded to the heart ventricle.

18. The ventricular assist device as recited in claim 1, in which at least one of the gel-filled pad means includes electrode means for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle.

19. The ventricular assist device as recited in claim 18, in which the electrode means is formed of a titanium wire mesh.

20. The ventricular assist device as recited in claim 1, in which each of the gel-filled pad means includes surface portion means for promoting ventricle tissue growth to the gel-filled pad means.

21. The ventricular assist device as recited in claim 20, in which the surface portion means for promoting tissue growth are formed of DACRON (polyester).

72. The flexible cardiac compression pad as recited in claim 20, in which the tissue growth-promoting surface portion means are formed of a soft, open-celled urethane foam.

22. A cardiac compression assembly which is intended for use in a cardiac assist device and which includes:

a movable pressure plate;

gel-filled pad means mounted on the pressure plate and being adapted for engaging an outer surface of at least one heart ventricle; and

mounting means for mounting the cardiac compression assembly in a cardiac assist device.

23. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means has a generally concave configuration so as to be adapted to conform to the heart ventricle.

24. The cardiac compression assembly as recited in claim 22, in which the pressure plate has an outer periphery, and the gel-filled pad means on the pressure plate extends beyond the outer periphery of the plate.

25. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means includes means which is adapted for gluing and/or suturing the cardiac compression assembly to the heart ventricle.

26. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad includes a hollow sheath formed of soft, electrically insulating material.

27. The cardiac compression assembly as recited in claim 26, in which the soft, electrically insulating material of the sheath has a specific gravity and stiffness similar to that of human muscle tissue so as to be adapted to be easily deformed.

28. The cardiac compression assembly as recited in claim 27, in which the material of the sheath is a polyurethane elastomer.

29. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means is filled with a soft gel having the characteristics of polyurethane or silicone.

30. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means has an undulating surface formed of a series of multiple raised portions and adapted to engage the heart ventricle so as to shrink and expand with the ventricle.

31. The cardiac compression assembly as recited in claim 30, in which selected ones of the raised portions include surface portion means adapted to promote ventricle tissue growth to the gel-filled pad means.

32. The cardiac compression assembly as recited in claim 31, in which the tissue growth-promoting surface portion means is formed of DACRON (polyester).

33. The cardiac compression assembly as recited in claim 32, in which the raised portions of the undulating surface are intersecting rows of raised dimples.

34. The cardiac compression assembly as recited in claim 33, in which the gel-filled pad means includes electrode means for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle.

35. The cardiac compression assembly as recited in claim 34, in which the electrode means is mounted in depressed portions of the undulating surface of the gel-filled pad means between selected ones of the raised dimples.

36. The cardiac compression assembly as recited in claim 35, in which the electrode means is in the form of a grid having intersecting strip portions which define dimple-receiving openings therebetween.

37. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means has opposite sides each having an undulating surface formed by a series of multiple raised portions.

38. The cardiac compression assembly as recited in claim 37, in which the raised portions of the undulating surfaces are formed by intersecting rows of dimples, with selected ones of the dimples on one side of the gel-filled pad means being bonded to the pressure plate, and selected ones of the dimples on the opposite side of the gel-filled pad means being adapted to be bonded to the heart ventricle.

39. The cardiac compression assembly as recited in claim 22, in which the gel-filled pad means includes surface portion means for promoting ventricle tissue growth to the gel-filled pad means.

40. The cardiac compression assembly as recited in claim 39, in which the surface portion means for promoting tissue growth are formed of DACRON (polyester).

41. A cardiac compression assembly which is intended for use in a cardiac assist device and which includes:

a movable pressure plate;

flexible pad means mounted on the pressure plate and being adapted for engaging an outer surface of at least one heart ventricle, the flexible pad means having an undulating surface on at least one side thereof formed by a series of multiple raised portions; and

mounting means for mounting the cardiac compression assembly in a cardiac assist device.

42. The cardiac compression assembly as recited in claim 41, in which selected ones of the raised portions are secured to the pressure plate.

43. The cardiac compression assembly as recited in claim 41, in which selected ones of the raised portions are adapted to be secured to the heart ventricle.

44. The cardiac compression assembly as recited in claim 41, which further comprises electrode means mounted in depressed portions of the undulating surface between selected ones of the raised portions, for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle.

45. The cardiac compression assembly as recited in claim 41, in which the raised portions of the pad undulating surface are intersecting rows of raised dimples.

46. The cardiac compression assembly as recited in claim 45, which further comprises electrode means for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle, the electrode means being mounted in depressed portions of the pad undulating surface between selected ones of the raised dimples and comprising a grid having intersecting strip portions which define dimple-receiving openings therebetween.

47. The cardiac compression assembly as recited in claim 41, in which an opposite side of the flexible pad means also has an undulating surface formed by a series of multiple raised portions.

48. The cardiac compression assembly as recited in claim 47, in which the raised portions of the opposite sides of the flexible pad means are intersecting rows of raised dimples.

49. The cardiac compression assembly as recited in claim 41, in which selected ones of the raised portions include surface portion means adapted to promote ventricle tissue growth to the pad means.

50. The cardiac compression assembly as recited in claim 49, in which the tissue growth-promoting surface portion means are formed of DACRON (polyester).

51. A flexible cardiac compression pad, which comprises:

a flexible hollow sheath adapted for engaging a heart ventricle and formed of a soft, electrically insulating material; and

a soft gel filling the hollow sheath.

52. The flexible cardiac compression pad as recited in claim 51, in which the sheath has a generally concave configuration so as to be adapted to conform to the heart ventricle.

53. The flexible cardiac compression pad as recited in claim 51, in which the soft electrically insulating material of the sheath has a specific gravity and stiffness similar to that of human muscle tissue so as to be adapted to be easily deformed.

54. The flexible cardiac compression pad as recited in claim 53, in which the material of the sheath is a polyurethane elastomer.

55. The flexible cardiac compression pad as recited in claim 51, in which the soft gel has the characteristics of polyurethane or silicone.

56. The flexible cardiac compression pad as recited in claim 51, in which the sheath has an undulating surface on at least one side thereof formed by a series of multiple raised portions.

57. The flexible cardiac compression pad as recited in claim 56, which further comprises electrode means mounted in depressed portions of the undulating surface between selected ones of the raised portions, for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle.

58. The flexible cardiac compression pad as recited in claim 56, in which an opposite side of the flexible sheath also has an undulating surface formed by a series of multiple raised portions.

59. The flexible cardiac compression pad as recited in claim 58, in which the raised portions on the opposite sides of the flexible sheath are intersecting rows of raised dimples.

60. The flexible cardiac compression pad as recited in claim 56, in which the raised portions of the pad undulating surface are intersecting rows of raised dimples.

61. The flexible cardiac compression pad as recited in claim 60, which further comprises electrode means for transmitting signals from the heart ventricle and/or applying signals to the heart ventricle, the electrode means being mounted in depressed portions of the pad undulating surface between selected ones of the raised dimples and comprising a grid having intersecting strip portions which define dimple-receiving openings therebetween.

62. The flexible cardiac compression pad as recited in claim 51, in which one side of the sheath includes surface portion means for promoting ventricle tissue growth to the sheath.

63. The flexible cardiac compression pad as recited in claim 62, in which the tissue growth-promoting surface portion means are formed of DACRON (polyester).

64. The flexible cardiac compression pad as recited in claim 62, in which the tissue growth-promoting surface portion means are formed of a soft, open-celled urethane foam.

65. A flexible cardiac compression pad, which comprises:

a flexible body member having opposite sides; and

a series of multiple raised portions defining an undulating surface on at least one side of the body member.

66. The flexible cardiac compression pad as recited in claim 65, which further comprises electrode means disposed on the at least one side of the body member between selected ones of the raised portions.

67. The flexible cardiac compression pad as recited in claim 66, in which the raised portions are rows of intersecting raised dimples and the electrode means is in the form of a grid having intersecting strips which define dimple-receiving openings therebetween.

68. The flexible cardiac compression pad as recited in claim 65, which further comprises:

a series of multiple raised portions also defining an undulating surface on an opposite side of the body member.

69. The flexible cardiac compression pad as recited in claim 68, in which the raised portions on both sides of the body member are intersecting rows of raised dimples.

70. The flexible cardiac compression pad as recited in claim 65, which further comprises:

surface portion means on selected ones of the raised portions for promoting tissue growth between a heart ventricle and the body member.

71. The flexible cardiac compression pad as recited in claim 70, in which the tissue growth-promoting surface portion means are formed of DACRON (polyester).

73. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises;

a pumping means which includes a plurality of essentially circumferentially arranged movable ventricle compression assemblies adapted to be positioned around a heart ventricle;

a support member adapted to be positioned adjacent an apex of the heart ventricle;

means for pivotally mounting lower ends of the circumferentially arranged movable ventricle compression assemblies on the support member; and

operating means for cyclically pivoting the plurality of circumferentially arranged movable ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling.

74. The ventricular assist device as recited in claim 73, in which the operating means includes a plurality of hydraulic fluid actuators, one for each of the ventricle compression assemblies.

75. The ventricular assist device as recited in claim 74, in which each of the actuators includes a piston disposed in a wall of a cylinder.

76. The ventricular assist device as recited in claim 75, in which each piston includes a piston sealing ring.

77. The ventricular assist device as recited in claim 75, in which each piston and cylinder is of an arcuate partial toroid construction.

78. The ventricular assist device as recited in claim 75, in which each piston and cylinder is of linear, straight-line construction.

79. The ventricular assist device as recited in claim 74, n which the operating means includes a hydraulic fluid manifold located adjacent to the ventricle compression assembly supporting means, each of the actuators including a piston and a cylinder in fluid communication with the manifold.

80. The ventricular assist device as recited in claim 79, in which the manifold and the fluid cylinders are of integral one-piece construction.

81. The ventricular assist device as recited in claim 74, in which each of the ventricle compression assemblies comprises a pressure plate and a gel-filled pad supported on the pressure plate.

82. The ventricular assist device as recited in claim 81, in which a ventricle-engaging surface of the gel-filled pad is at least partially formed of a porous foam.

83. The ventricular assist device as recited in claim 82, in which the ventricle engaging surface of the gel-filled pad is of undulating construction with spaces between undulations of the surface filled with the porous foam.

84. The ventricular assist device as recited in claim 83, in which an opposite side surface of the gel-filled pad is of smooth construction and bonded to the pressure plate.

85. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes one or more movable ventricle compression assemblies;

gel-filled pad means forming respective parts of the one or more movable ventricle compression assemblies, said gel-filled pad means being adapted for engaging an outer surface of at least one heart ventricle; and

operating means for cyclically actuating the one or more ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling;

each ventricle compression assembly including a pressure plate connected to the operating means and having an outer periphery, with each of the gel-filled pad means being mounted on a respective one of the plates and extending beyond the outer periphery of the plate; and

the pressure plate of each of the one or more movable ventricle compression assemblies being mounted on a compressive arm via an axle/bearing mount such that the pressure plate and the gel-filled pad means are adapted to follow the natural movement of the heart ventricle.

86. A cardiac compression assembly which is intended for use in a cardiac assist device and which includes:

a pressure plate;

gel-filled pad means mounted on the pressure plate and being adapted for engaging an outer surface of at least one heart ventricle; and

mounting means for mounting the cardiac compression assembly in a cardiac assist device;

the pressure plate having an outer periphery with the gel-filled pad means on the pressure plate extending beyond the outer periphery of the plate; and

the pressure plate being mounted on a compressive arm via an axle/bearing mount such that the pressure plate and the gel-filled pad means are adapted to follow the natural movement of the heart ventricle.

87. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes a plurality of essentially circumferentially arranged movable ventricle compression assemblies adapted to be positioned around a heart ventricle;

means for supporting lower ends of the circumferentially arranged movable ventricle compression assemblies adjacent and around an apex of the heart ventricle; and

operating means for cyclically actuating the plurality of circumferentially arranged movable ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling;

the lower ends of the ventricle compression assemblies being pivotally mounted on the supporting means and the operating means including a vertically movable camming means surrounding the supporting means for moving the ventricle compression assemblies to their ventricle compressing positions.

88. The ventricular assist device as recited in claim 87, in which the operating means includes a rotatable camming means for causing vertical movement of the vertically movable camming means.

89. The ventricular assist device as recited in claim 88, in which the operating means further includes a gear means for rotating the rotatable camming means.

90. The ventricular assist device as recited in claim 89, in which the operating means further includes a drive shaft on which the gear means is mounted, a motor and a speed reducer, the motor driving the drive shaft through the speed reducer.

97. The ventricular assist device as recited in claim 90, in which:

the energy connecting means is mounted in a sealed casing filled with a hydraulic fluid; and

the hydraulic fluid pump draws hydraulic fluid from within the casing and forces the fluid to the fluid-operated means, to actuate the ventricle compression assemblies.

98. The ventricular assist device as recited in claim 97, which further includes a normally closed electrical solenoid valve which forms a parallel path around the hydraulic fluid pump, the solenoid automatically opening in response to an electrical power failure to permit hydraulic fluid in the operating means to return to the sealed casing.

99. The ventricular assist device as recited in claim 97, which further comprises:

expandable-and-contractible means in the sealed casing for expanding in response to the hydraulic pump drawing fluid from the sealed casing, to prevent formation of a vacuum in the sealed casing, the expandable-and-contractible means having an interior filled with hydraulic fluid;

flexible sealed covering means for surrounding the fluid-operated means and the lower ends of the ventricle compression assemblies, the covering means also having an interior filled with hydraulic fluid; and

conduit means for connecting the interiors of the expandable-and-contractible means and the covering means, so that fluid flows therebetween upon expansion and contraction of the expandable-and-retractable means.

100. The ventricular assist device as recited in claim 99, in which the expandable-and-contractible means is a bellows.

91. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes at least six essentially circumferentially arranged movable ventricle compression assemblies adapted to be positioned around a heart ventricle;

means for supporting lower ends of the circumferentially arranged movable ventricle compression assemblies adjacent and around an apex of the heart ventricle; and

operating means for cyclically actuating the circumferentially arranged movable ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling.

92. The ventricular assist device as recited in claim 91, which includes at least eight of the ventricle compression assemblies.

93. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes a plurality of essentially circumferentially arranged movable ventricle compression assemblies adapted to be positioned around a heart ventricle;

means for supporting lower ends of the circumferentially arranged movable ventricle compression assemblies adjacent and around an apex of the heart ventricle; and

operating means for cyclically actuating the plurality of circumferentially arranged movable ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling;

the lower ends of the ventricle compression assemblies being pivotally mounted on the supporting means and the operating means including hydraulic fluid-operating means for actuating the ventricle compression assemblies.

94. The ventricular assist device as recited in claim 93, in which the hydraulic fluid-operated means includes a bellows.

95. The ventricular assist device as recited in claim 93, in which the operating means includes energy converting means for converting electrical energy into hydraulic fluid energy for operating the hydraulic fluid-operated means.

96. The ventricular assist device as recited in claim 95, in which the energy converting means includes a hydraulic fluid pump and an electrical motor connected to drive the pump.

101. A ventricular assist device which can be implanted in a patient user exterior to the heart and which comprises:

a pumping means which includes a plurality of essentially circumferentially arranged movable ventricle compression assemblies adapted to be positioned around a heart ventricle;

means for supporting lower ends of the circumferentially arranged movable ventricle compression assemblies adjacent and around an apex of the heart ventricle;

operating means for cyclically actuating the plurality of circumferentially arranged movable ventricle compression assemblies, such that the ventricle is, first, compressed to aid blood ejection therefrom, and second, released to permit refilling;

the lower ends of the ventricle compression assemblies being pivotally mounted on the supporting means and the operating means including a plurality of hydraulic fluid actuators, one for each of the ventricle compression assemblies and each including a piston disposed in a wall of a cylinder;

means for collecting hydraulic fluid which may leak from the actuators;

a hydraulic fluid supply forming part of a hydraulic fluid system for operating the actuators;

pump means for transferring hydraulic fluid from the hydraulic fluid supply to operate the actuators; and

means for returning collected leakage fluid in the collecting means to the hydraulic fluid supply.

102. The ventricular assist device as recited in claim 101, in which the means for collecting leaking hydraulic fluid is a flexible sealed covering means for surrounding the actuators and the lower ends of the ventricle compression assemblies, the covering also having an interior filled with the hydraulic fluid.

103. The ventricular assist device as recited in claim 101, in which:

the hydraulic fluid collecting means, fluid supply, pump means and return means form a closed loop system;

the hydraulic fluid supply includes a sealed container;

the pump means includes a cylinder and a piston disposed in the sealed container, the piston being reciprocable in the cylinder by a reversible motor, and the cylinder being connected to the actuators and including an opening in a side wall thereof for drawing hydraulic fluid in the container into the cylinder upon retraction of the piston.