Cardiovascular implants of enhanced biocompatibility
Patent 5683442 Issued on November 4, 1997. Estimated Expiration Date: November 8, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Medical leads fabricated from low-modulus Ti-Nb-Zr alloys to provide enhanced biocompatibility and hemocompatibility. The medical leads may be surface hardened by oxygen or nitrogen diffusion or by coating with a tightly adherent, hard, wear-resistant, hemocompatible ceramic coating. It is contemplated that the Ti-Nb-Zr alloy can be substituted as a fabrication material for any portion of a medical lead that either comes into contact with blood thereby demanding high levels of hemocompatibility, or that is subject to microfretting, corrosion, or other wear and so that a low modulus metal with a corrosion-resistant, hardened surface would be desirable.
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