The stent, a mesh tube device designed to hold open blood vessels, has revolutionized management of coronary artery disease. The first successful stent was invented by Argentinian doctor Julio Palmaz (b. 1945). Palmaz had heard that blood vessels had a tendency to close up after balloon angioplasty, in which narrowed heart vessels are opened with a catheter.
Pafmaz had the idea of putting a "scaffold" inside the vessels to prevent them from closing over. Palmaz began working on creating prototypes of an implantable stent, using simple materials such as copper wire and a soldering iron. He modeled the mesh with a structure of staggered openings he just happened to find lying on his garage floor. The design proved perfect—the structure was collapsible but remained rigid when inserted into the blood vessel.
After testing his device on pigs and rabbits, Palmaz secured funding from the unlikely partnership of Phil Romano, a restaurant entrepreneur, and cardiologist Richard Schatz from the Brooke Army Medical Center. Calling themselves the Expandable Graft Partnership, the trio patented the device in 1988.
One complication was restenosis , the development of a blockage from scar tissue arising from implantation. The next stage was to produce drug- eluting stents to deliver therapeutic agents, such as sirolimus, to prevent that scarring from occurring. However, in a few cases these can lead to blood clots that cause heart attacks. The way forward currently being explored is to have biodegradable stents made of metals or polymers that slowly dissolve.
