Method for implanting a minimally invasive physiologic parameter recorder and introducer system

• US 8,280,499 B2
• Filed: 05/07/2012
• Issued: 10/02/2012
• Est. Priority Date: 01/30/2008
• Status: Expired due to Fees

• Current Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Original Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Inventors: Brockway, Brian P., Mills, Perry A.
• Primary Examiner(s): Dvorak, Linda
• Assistant Examiner(s): ANTISKAY, BRIAN MICHAEL
• Application Number:
  US13/465,314
• Publication Number:
  US 20120220849A1
• Time in Patent Office: 148 Days
• Field of Search: 600372-375, 600/377, 600508-510, 600/513, 600/515, 600518-519, 600544-547, 600/549, 607115-132
• US Class Current: 600/509
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 2560/063 Devices specially adapted for delivering implantable medical measuring apparatus
• CPC Class Codes: A61B 2560/066 catheters therefor
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 2562/18 Shielding or protection of sensors from environmental influences, e.g. protection from mechanical damage
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period
• CPC Class Codes: A61N 1/0504 Subcutaneous electrodes
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/375 Constructional arrangements, e.g. casings
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

An implantable monitoring device includes a flexible lead body that includes at least one sensing element. The device also includes a rigid main body connected to the flexible lead body at an attachment point. The rigid main body is generally centered about a longitudinal axis defined by the flexible lead body when the lead body is unflexed. The device further includes a measurement circuit, which is housed within the rigid main body and electrically coupled to the at least one sensing element of the flexible lead body and at least another sensing element on an outside surface of the rigid main body. The measurement circuit is configured to measure a potential difference between the at least one sensing element of the flexible lead body and the at least another sensing element of the main body.

Claims

1. A method for implanting a monitoring device subcutaneously in a body of a patient, the method comprising the steps of:

a) providing the monitoring device, comprising;

i) a main body extending along a longitudinal axis and comprising a hermetically sealed proximal housing section supporting at least one proximal sensing element on an external surface thereof, and a non-hermetically sealed distal housing section provided with an intermediate ring electrode disposed annularly around the longitudinal axis, the distal housing section being connected at an attachment location to a flexible lead body including at least one distal sensing element; and

ii) a measurement circuit housed within the hermetic poximal housing section, the measurement circuit being electrically connected to the proximal sensing element, the intermediate ring electrode, and the at least one distal sensing element of the flexible lead body,

iii) wherein the measurement circuit is configured to measure a potential difference between any two of the at least one distal sensing element of the flexible lead body, the at least one proximal sensing element, and the intermediate ring electrode of the main body;

b) assembling an introducer, comprising a sheath and a semi-flexible insert, by placing the semi-flexible insert within the sheath, the semi-flexible insert being sized and shaped at least in part to match, a size and shape of the monitoring device;

c) introducing a distal end of the introducer through an incision in the patient'"'"'s skin to a desired subcutaneous implant location site beneath the patient'"'"'s skin;

d) withdrawing the semi-flexible insert from the sheath without substantially disturbing the position of the sheath at the desired subcutaneous implant location site;

e) inserting the monitoring device into the sheath; and

f) withdrawing, in a direction opposite that which it was introduced, the sheath from the implant location site while applying pressure to the monitoring device, wherein an external surface of the sheath splits along an axis as the sheath surface is forced against the tapered section of the monitoring device while the sheath is being withdrawn.

2. The method of claim 1 including providing at least a portion of the sheath being sized and shaped in proportion to a corresponding portion of the semi-flexible insert.

3. The method of claim 1 including providing the distal end of the introducer being deflectable upon contacting a surface of a muscle layer and slidable across the surface of the muscle layer without penetrating the muscle layer.

4. The method of claim 1 including providing the external surface of the sheath comprising a surface modification along at least a portion of the longitudinal axis, the surface modification reducing a tensile strength of the external surface of the sheath along the axis.

10. The method of claim 1 including providing the semi-flexible insert and the monitoring device each including a tapered section that tapers from a first width at a proximal end of the tapered section to a second width, smaller than the first width, at a distal end of the tapered section.

11. The method of claim 1 including providing at least a portion of the main body tapering from a first width to a second width narrower than the first width.

12. The method of claim 11 including providing the portion of the main body tapering symmetrically about the longitudinal axis of the rigid main body.

13. The method of claim 11 including providing the portion of the main body tapering approximately linearly from the first width to the second width.

14. The method of claim 11 including providing the portion of the main body tapering non-linearly from the first width to the second width.

15. The method of claim 1 including providing a first portion of the main body tapering approximately linearly from a first width to a second width narrower than the first width, and a second portion of the main body tapering non-linearly from a third width to a fourth width narrower than the third width.

16. The method of claim 1 including providing the main body being rigid.

17. The method of claim 1 including providing a proximal width of the proximal housing section being substantially greater than a distal width of the distal housing section.

18. The method of claim 1 including providing a loop member on the main body.

19. The method of claim 18 including using the loop member to suture the device to body tissue.

20. The method of claim 18 including providing the monitoring device being extractable from an implant location by applying a withdrawal force to the loop member.

5. A method for implanting an implantable monitoring device in a subcutaneous implant region of a patient, the method comprising the steps of:

a) providing the monitoring device, comprising;

i) a main body extending along a longitudinal axis and comprising a hermetically sealed proximal housing section supporting at least one proximal sensing element on an external surface thereof, and a non-hermetically sealed distal housing section provided with an intermediate ring electrode disposed annularly around the longitudinal axis, the distal housing section being connected at an attachment location to a flexible lead body including at least one distal sensing element; and

ii) a measurement circuit housed within the hermetic proximal housing section, the measurement circuit being electrically connected to the proximal sensing element, the intermediate ring electrode, and the at least one distal sensing element of the flexible lead body,

iii) wherein the measurement circuit is configured to measure a potential difference between two of the at least one distal sensing element of the flexible lead body, the at least one proximal sensing element, and the intermediate ring electrode of the main body;

b) introducing an insert device to the subcutaneous region of the patient, the insert device having an internal chamber that is generally in the shape of at least a portion of the implantable monitoring device;

b) inserting, after the insert device has been introduced to the subcutaneous region, the implantable monitoring device to the internal chamber of the insert device; and

c) removing the insert device from the subcutaneous region while leaving the implantable monitoring device at the subcutaneous region.

6. The method of claim 5 including removing the insert device from the subcutaneous region by withdrawing, in a direction opposite from that which it was introduced, the insert device from the subcutaneous region while applying pressure to the monitoring device.

7. The method of claim 5 including the subcutaneous region being above a pectoral fascia of the patient.

8. The method of claim 5 including at least a portion of the subcutaneous region being below a pectoral fascia of the patient.

9. The method of claim 8 including the entire subcutaneous region being below the pectoral fascia.

21. The method of claim 5 including providing the insert device including a surface modification to reduce a tensile strength of the insert device.

22. The method of claim 5 including providing, when unflexed, the main body and the flexible extension being substantially collinear with the longitudinal axis.

23. A method for implanting a monitoring device subcutaneously in a body of a patient, the method comprising the steps of:

a) providing the monitoring device, comprising;

i) a main body extending along a longitudinal axis and comprising a hermetically sealed proximal housing section supporting at least one proximal sensing element on an external surface thereof, and a non-hermetically sealed distal housing section provided with a ring electrode disposed annularly around the longitudinal axis, the distal housing section being connected to a flexible lead body at an attachment point; and

ii) a measurement circuit housed within the hermetic proximal housing section, the measurement circuit being electrically connected to the proximal sensing element, the ring electrode, and at least one distal sensing element of the flexible lead body,

iii) wherein the measurement circuit is configured to measure a potential difference between any two of the at least one distal sense electrode on the flexible lead body, the at least one proximal sense electrode, and the intermediate ring electrode on the main body;

b) assembling an introducer, comprising a sheath and a semi-flexible insert, by placing the semi-flexible insert within the sheath, the semi-flexible insert being sized and shaped at least in part to match a size and shape of the monitoring device;

c) introducing a distal end of the introducer through an incision in the patient'"'"'s skin to a desired subcutaneous implant location site beneath the patient'"'"'s skin;

d) withdrawing the semi-flexible insert from the sheath without substantially disturbing the position of the sheath at the desired subcutaneous implant location site;

e) inserting the monitoring device into the sheath; and

f) withdrawing, in a direction opposite that which it was introduced, the sheath from the implant location site while applying pressure to the monitoring device, wherein an external surface of the sheath splits along an axis as the sheath surface is forced against the tapered section of the monitoring device while the sheath is being withdrawn.