Self-sealing insulation employed on a catheter or lead

A method of sealing an implantable electrical medical lead, the integrity of which may be compromised, the lead extending between a proximal end for attachment with a connector for providing an electrical connection with a pulse generator and a distal end for attachment to a distal electrode, the method comprising:

• (a) with an insulating sheath of flexible resilient material, covering an electrical conductor extending from the proximal end to the distal end;
• and
• (b) providing the insulating sheath with self sealing properties to re-insulate the electrical conductor in the event a rupture of the sheath should occur which exposes the electrical conductor;
• wherein the insulating sheath is of polymeric material;
• and
• including the step of:
• (c) embedding the polymeric material of the insulating sheath with a plurality of pellets, each pellet having a frangible shell containing a liquid sealing material that fills a rupture and solidifies when the frangible shell is broken;
• wherein the flexible resilient material of the insulating sheath is selected from the group consisting of silicone or polyurethane or a combination thereof;
• wherein the shell of each pellet is a polycarbonate;
• and
• wherein the liquid sealing material in each pellet is epoxy.

An implantable electrical medical lead extending between proximal and distal ends for use with a pulse generator to be implanted within a human body, the lead comprising:

• at least one electrode;
• a connector configured to provide an electrical connection with the pulse generator;
• an electrical conductor within the lead extending between a proximal end attached to the connector and a distal end attached to the at least one electrode;
• an insulating sheath of flexible resilient material normally covering the electrical conductor and extending from the proximal end to the distal end;
• and
• a self-sealing member operative to re-insulate the electrical conductor in the event of an abrasion of the sheath;
• wherein the insulating sheath is of polymeric material embedded with a plurality of pellets, each pellet having a frangible shell containing a liquid sealing material that fills a rupture and solidifies when the frangible shell is broken;
• wherein the flexible resilient material of the insulating sheath is selected from the group consisting of silicone or polyurethane or a combination thereof;
• wherein the material of the shell of each pellet is at least one of a polycarbonate and a polyvinyl chloride;
• and
• wherein the liquid sealing material in each pellet is a body (temperature) curable adhesive.