RF shield for an implantable lead

• US 9,402,996 B2
• Filed: 02/11/2015
• Issued: 08/02/2016
• Est. Priority Date: 02/11/2014
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Tran, Binh C., Walker, Joseph, Carpenter, Greg P., Gordon, Jack
• Primary Examiner(s): Lavert, Nicole F
• Application Number:
  US14/619,460
• Publication Number:
  US 20150224303A1
• Time in Patent Office: 538 Days
• Field of Search: 607/36, 607/119
• US Class Current: 1/1
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/086 Magnetic resonance imaging [MRI] compatible leads
• CPC Class Codes: A61N 1/3718 Monitoring of or protection against external electromagnetic fields or currents

Abstract

Various embodiments concern shielding an implantable lead from RF energy associated with MRI scans. The lead can include a distal region, a proximal region, an intermediate region between the distal region and the proximal region, at least one electrode disposed on the distal region, and at least one conductor extending from the proximal region to the at least one electrode. Implanting of the lead can include coiling a portion of the intermediate region to define one or more loops and selectively shielding the one or more loops of the lead with a RF shield. The RF shield can comprise metallic material and can be configured to reduce RF signal coupling to the at least one conductor along the one or more loops.

Claims

1. A method of shielding an implantable lead, the method comprising:

implanting a lead in a patient, the lead having a distal region, a proximal region, an intermediate region between the distal region and the proximal region, at least one electrode disposed on the distal region, and at least one conductor extending from the proximal region to the at least one electrode;

coiling a portion of the intermediate region to define one or more loops; and

selectively shielding the one or more loops of the lead with an RF shield, the RF shield comprising metallic material and configured to reduce RF signal coupling to the at least one conductor along the one or more loops.

2. The method of claim 1, wherein the RF shield comprises a metallic bag, and selectively shielding the portion of the intermediate region comprises placing the metallic bag over the one or more loops.

3. The method of claim 1, wherein the RF shield comprises a flexible metallic sleeve, and selectively shielding the one or more loops comprises sliding the flexible metallic sleeve over the portion of the intermediate region.

4. The method of claim 1, wherein the lead comprises a polymeric body defining an exterior surface of the lead, the RF shield is a layer of metallic material deposited on the exterior surface only along the portion of the lead, and selectively shielding the one or more loops of the lead comprises coiling the portion of the lead on which the layer of metallic material is deposited into the one or more loops.

5. The method of claim 1, wherein selectively shielding the one or more loops of the lead comprises placing the RF shield over the intermediate region, and wherein the method further comprises removing the RF shield from over the intermediate region while leaving the lead implanted within the patient.

6. The method of claim 1, wherein the RF shield includes an identification tag indicating MRI conditional compatibility, and the method further comprises transcutaneously reading the indication of MRI conditional compatibility from the identification tag while the lead is implanted in the patient.

7. The method of claim 1, wherein the RF shield is placed along the lead in the selectively shielding step such that no portion of the RF shield extends into the vasculature of the patient.

8. The method of claim 1, wherein the lead is shielded in the selectively shielding step such that only the one or more loops are shielded by the RF shield.

9. The method of claim 1, further comprising suturing the RF shield to one or both of fix the RF shield in position over the lead and anchor the RF shield at an implant location.

10. An implantable lead having a distal region, a proximal region, and an intermediate region therebetween, the lead comprising:

at least one electrode disposed on the distal region of the lead;

at least one conductor extending from the proximal region to the distal region, the at least one conductor electrically coupled to the at least one electrode, respectively;

a polymeric body radially surrounding the at least one conductor, the polymeric body extending from the proximal region to the distal region, the polymeric body configured to electrically insulate the at least one conductor; and

an RF shield surrounding an outer surface of the polymeric body and only along the intermediate region of the elongated member, the lead configured to be coiled into one or more loops along the intermediate region, the RF shield configured to reduce RF signal coupling to the at least one conductor along the one or more loops.

11. The lead of claim 10, wherein the RF shield is selectively moveable over the intermediate region.

12. The lead of claim 10, wherein the RF shield includes at least one of a metallic film and a metallic mesh.

13. The lead of claim 10, wherein the RF shield comprises a metallic bag configured to envelope the one or more loops.

14. The lead of claim 10, wherein the RF shield comprises a sleeve configured to slide over the lead.

15. The lead of claim 10, wherein the RF shield comprises a metallic layer deposited on an exterior surface of the polymeric body.

16. The lead of claim 10, wherein the RF shield only shields the one or more loops of the lead.

17. The lead of claim 10, wherein the RF shield is configured to be removed from the lead after implantation while allowing the lead to remain implanted.

18. The lead of claim 10, wherein the RF shield includes a remotely readable identification tag indicating magnetic resonance conditional usage.

19. An implantable lead, the lead comprising:

a lead body, the lead body configured to be coiled into one or more loops;

at least one electrode;

at least one conductor extending within the lead body, the at least one conductor electrically coupled to the at least one electrode, respectively; and

an RF shield, the RF shield moveable over the lead body and removable from the lead body, the RF shield configured to surround the one or more loops and reduce RF signal coupling to the at least one conductor along the one or more loops.

20. The lead of claim 19, wherein the RF shield only shields the one or more loops of the lead.