Medical Technology

What is a Heart Stent

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"What is a Heart Stent"
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In medicine a major problem concerns blockages appearing in blood vessels that prevent blood, and therefore oxygen, from reaching the cells and tissues where it is needed. Now obviously the ideal thing would be to simply remove the blockage from the blood vessel. Unfortunately, this is not possible in some cases because it is too dangerous or too difficult or maybe because it would not provide a lasting solution to the problem.

So what else can be done? The other way to tackle the problem is to physically open up the blocked blood vessel and to keep it held open artificially. A stent is the name given to the expandable wire or laser-perforated tube that is used to achieve this desirable end. A heart stent is a particular variety of stent that is used in the treatment of coronary heart disease instead of using bypass surgery.

The very first examples of medical stents were those created by a Swedish engineer called Hans Wallsten. These devices were originally called Wallstents, and this was later shortened to stents. It was not until 1969 that the first heart stent came along. This saw Charles Theodore Dotter carrying out experiments on the peripheral arteries of a dog. It was as recently as 1986 that Jacques Puel, working in France, performed the first human coronary heart stent implantation.

The procedure during which a heart stent is inserted into a coronary artery is known as percutaneous coronary intervention or, in a term more familiar to many, angioplasty. This procedure will usually involve either a bare-metal stent or a drug-eluting stent. The bare-metal stent is a thin, mesh-like wire, originally made of stainless steel but now made of a cobalt chromium alloy instead.

The drug-eluting heart stent is a fairly recent advance in stent technology. The key to the technology is the coating of drugs on the stent aimed at preventing cell proliferation. The drug paclitaxel is an example of the type of drug that is used as an anti-proliferative agent (this is a drug that is also used more widely in cancer treatment).

This drug releasing process prevents potential problems such as fibrosis (the build up of excess connective tissue) and thrombus (unwanted blood clotting). This type of heart stent was first implanted in 2001. The introduction of this technology has resulted in improved survival rates. This in turn has swung the balance away from using bypass surgery and towards more extensive use of stent implantation.

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