You can freely build on How Doctors Implant a Permanent Stent Using a Balloon

What this patent covers

This patent describes a method for implanting a medical device, called a prosthesis or intraluminal graft, inside a body passageway like a blood vessel. First, the prosthesis is placed onto a catheter (Claim 1). The catheter and prosthesis are then inserted into the body passageway (Claim 1). Once at the desired location, a part of the catheter, specifically an inflatable balloon (Claim 3), is expanded. This expansion forces the prosthesis outward, permanently deforming it beyond its elastic limit (Claim 1) to contact the walls of the passageway. The prosthesis, often a wire mesh tube made of tantalum (Claims 4, 5), then remains in place to prevent the passageway from collapsing (Claim 7). After expansion, the balloon is deflated, and the catheter is removed (Claim 2). For example, this method can be used to open a narrowed artery and keep it wide.

What is now free to use

All 0 claims of US 4733665 are in the public domain. Specifically:

The 0 dependent claims add narrowing limitations and are also free.

What is NOT covered

Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.

• Grafts that expand on their own without needing a balloon or other external force from the catheter.

• Grafts that are not permanently deformed when expanded, meaning they would spring back to their original size.

• Methods where the graft is expanded by a mechanism other than an inflatable portion of the catheter.

• Grafts that are not delivered upon a catheter but are instead injected or deployed differently.

• Grafts that are not tubular or made of intersecting elongate members, as described in Claim 13.

Who is building on this today

Major medical device companies like Medtronic, Abbott Laboratories, Boston Scientific, and Johnson & Johnson (through its Cordis division, which commercialized the Palmaz stent) have built extensive product lines based on balloon-expandable stent technology. Many startups also continue to innovate in this space, developing new materials and designs for these types of implants.

Products built on expired version of this technology

How to cite this patent in your documentation

Expandable Grafts Partnership. US Patent 4733665. Expandable intraluminal graft, and method and apparatus for implanting an expandable intraluminal graft. Granted 1988, expired 2005. Now in the public domain.

Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.

PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.