Patent ID: 8452416

Claim:
A medical lead assembly comprising: a medical implantable lead being adapted to be attached with a distal end of the medical implantable lead to an organ inside a human or animal body, wherein the medical implantable lead is formed with an inner lumen extending along essentially an entire length of the medical implantable lead; a support core having a suitable cross sectional dimension such that it is insertable into the lumen in order to increase stiffness of the medical implantable lead along its length during its working life when being implanted into a body; the medical implantable lead being sectioned in portions having different stiffness along its length; and the support core being sectioned with portions having different flexibility that inversely correspond to the sections of the medical implantable lead, and said sections of the support core being relatively located, when the support core is inserted into the medical implantable lead, to cause portions of the support core having low flexibility to be positioned at portions of the medical implantable lead having high flexibility, and vice versa; wherein said medical implantable lead comprises a wire coil having alternating tightly wound coil sections and loosely wound coil sections having lower stiffness as compared to the tightly wound coil sections; and wherein said medical implantable lead comprises an outer wire coil coaxially arranged around an inner wire coil and separated by an inner flexible tube, the outer wire coil has alternating tightly wound coil sections and loosely wound coil sections and the inner wire coil has alternating tightly wound coil sections and loosely wound coil sections, the tightly wound coil sections of the outer wire coil are aligned with the tightly wound coil sections of the inner wire coil and the loosely wound coil sections of the outer wire coil are aligned with the loosely wound coil sections of the inner wire coil.