06298272 is referenced by 64 patents and cites 9 patents.

An implantable lead, being either a fixed or retractable/extendable lead, having a distal tip electrode is adapted for implantation on or about the heart and for connection to a system for monitoring or stimulating cardiac activity. The electrode includes a mechanical fastener such as a fixation helix for securing the electrode to cardiac tissue, which may or may not be electrically active. The implantable electrode with a helical tip may comprise:

an electrode having a distal end and a proximal end; and

a helix disposed within the electrode, which helix is aligned along a radial axis of the electrode to the distal end; and

the implantable electrode having at least one feature selected from the group consisting of:

a) the helix having a coating of an insulating material on its surface,

b) the helix having its surface beyond the distal end of the electrode and the distal end of the electrode having a porous conductive surface at a base of the helix,

c) a porous conductive element, screen or mesh at a base of the helix, and

d) a porous conductive element at the end of the electrode having an insulating coating covering from 5-95% of the surface of the porous conductive element.

The electrode may further include an electrode tip having a porous electrical conductive element, such as a mesh screen, disposed on a surface at the distal end of the electrode tip, which can be used as a sensing or pacing interface with the cardiac tissue. The porous electrically conductive element will usually be positioned at the base of the helix (when extended if extendable/retractable). The mesh or screen may provide a guiding mechanism for the helix as it travels out of the electrode for securing the electrode to the heart or other muscle or organ. The guiding mechanism may include a groove within the mesh screen. Alternatively, the guiding mechanism includes a guiding bar on which the fixation helix rides on during extension or retraction. In combination with each of these high impedance tips, a drug delivery system is provided at least the majority of which drug delivery system is provided from a source within a volume which is within the structural walls of the lead and/or within a volume having its major dimensions and/or at least 50% of its volume generally within the projected area of the tip.

High impedance electrode tip with internal drug delivery capability
Application Number
Publication Number
6298272 (B1)
Application Date
March 29, 1999
Publication Date
October 2, 2001
Jeffrey T Bartig
Randall M Peterfeso
St. Paul
Schwegman Lundberg Woessner & Kluth P A
Cardiac Pacemakers
A61N 1/05
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