MicroPort Scientific has been granted a patent for a method of forming leads for implantable medical devices. The leads can be implanted in the venous, arterial, or lymphatic networks and have a diameter of no greater than 1.5 French (0.5 mm). The leads consist of micro-cables with electrically conductive core cables and polymer insulation layers. The insulation layer has exposed areas that form detection/stimulation electrodes. GlobalData’s report on MicroPort Scientific gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on MicroPort Scientific, Glucose monitoring wearbles was a key innovation area identified from patents. MicroPort Scientific's grant share as of September 2023 was 46%. Grant share is based on the ratio of number of grants to total number of patents.
Implantable medical device leads with small diameter and exposed electrodes
A recently granted patent (Publication Number: US11771889B2) describes a method for forming a lead to be used with an implantable medical device. The method involves providing a plurality of microcables, each consisting of a core cable and an insulation layer. The core cable is made up of multiple cable strands. The method includes forming at least one exposed area within the insulation layer for each microcable, allowing for the exposure of bare core cable portions. These exposed areas serve as electrodes for the lead. The insulation layer is composed of two heat-shrinkable polymer sheaths, with the exposed area formed between them. The resulting lead has an outer diameter of no greater than 1.5 French.
In addition to the basic method, several additional steps are described in the patent. One such step involves longitudinally shifting the distal ends of the microcables from each other. This produces a progressive reduction in diameter and introduces a stiffness gradient in the distal portion of the lead. Another step involves positioning a central microcable in the center of the microcables, which includes a distal electrode. The core cable of each microcable is formed by twisting multiple elementary strands together. These elementary strands can be made from a composite structure consisting of a structuring material and a radiopaque material. The outer layer of the elementary strands is made from a material with low magnetic susceptibility.
The insulation layer of the lead is made from a fluoropolymer. The microcables are coupled together in a twisted configuration within the lead, with a center microcable surrounded by peripheral microcables. This configuration forms a multipolar detection/stimulation distal active portion of the lead. The exposed area extends 360 degrees around the circumference of the lead over a length corresponding to one turn of the microcable within the twisted configuration. A dipole can be formed with two non-consecutive microcables, with the exposed areas of these microcables positioned across from each other within the twisted configuration.
The lead can also include inner and outer rings. The inner ring is positioned on each bare core cable portion of the microcables, while the outer ring surrounds all the microcables and is in electrical contact with the inner ring. Each microcable is individually conductive and individually selectable by an implantable medical device, allowing for selective stimulation of the separately exposed areas.
Overall, this patent describes a method for forming a lead for an implantable medical device that offers flexibility, individual conductance, and selective stimulation capabilities. The resulting lead has a small outer diameter, making it suitable for use in medical applications.