Stent

In medicine, a stent is a small tube made from a special metal alloy or a flexible material called a polymer. It is placed inside a narrow or blocked blood vessel or duct to keep the passage open, allowing blood or other fluids to flow properly again.

Stenting is the process of putting a stent into the body. This helpful procedure is often used when diseases, such as atherosclerosis, have made an artery too narrow. Unlike a shunt, which connects two parts of the body that were not connected before, a stent simply keeps an existing passage open.

There are many kinds of stents for different uses. Coronary stents are used in the heart during coronary angioplasty, and drug-eluting stents are very common. Other stents help with problems in the kidneys, brain blood vessels, and even the tubes that carry urine. Some stents are used to treat cancer or to help with digestion problems.

The idea of using a stent started with Charles Stent, an English dentist, in the 1800s. The use of stents in the heart began in 1986 when doctors Jacques Puel and Ulrich Sigwart used them to stop blood vessels from closing during heart procedures. Today, stents are carefully checked before being used in patients to make sure they are safe and work well.

Stent types

By destination organ

Coronary stent

Main article: Coronary stent

Coronary stents are tiny tubes placed in the heart’s blood vessels to keep them open. They are often used during a procedure called coronary angioplasty. Most coronary stents today release medicine to prevent the arteries from narrowing again. This helps reduce chest pain and can improve survival after a heart attack.

Vascular stent

Vascular stents are used to treat narrowed or blocked blood vessels in parts of the body like the neck, pelvis, and legs. They are made from flexible materials to fit well inside blood vessels. These stents help keep blood flowing freely and are used in treatments for conditions like strokes and heart attacks.

Ureteric stent

Main article: Ureteric stent

Ureteral stents are small tubes placed in the tubes that carry urine from the kidneys to the bladder. They are used when a kidney stone blocks the flow of urine. These stents keep the passage open until the stone can be removed.

Prostatic stent

Main article: Prostatic stent

Prostatic stents are placed to help men urinate more easily when their prostate gland is enlarged. They can be temporary or permanent. Temporary stents are easier to remove, while permanent ones stay in place to keep the urinary passage open.

Colon and Esophageal stents

Main article: Esophageal stent

Colon and esophageal stents are used to help people with advanced cancer in the colon or esophagus. They keep these passages open so food and waste can pass through more easily.

Pancreatic and biliary stents

Pancreatic and biliary stents help drain fluids from the gallbladder, pancreas, and bile ducts into the small intestine. They are used when gallstones or other blockages are present.

Glaucoma drainage stent

Glaucoma drainage stents are used to help drain fluid from the eye to reduce pressure inside the eye.

By properties or function

Bare-metal stent

Main article: Bare-metal stent

A bare-metal stent is a simple metal tube used to keep blood vessels open. Some of these stents have a fabric coating and are used in special surgeries.

Bioresorbable stent

Main article: Bioresorbable stent

A bioresorbable stent is made from material that dissolves over time. It is used to open clogged arteries and then is absorbed by the body, allowing the artery to return to its natural state.

Drug-eluting stent

Main article: Drug-eluting stent

Drug-eluting stents are tiny tubes placed in narrowed blood vessels that slowly release medicine to prevent the vessels from narrowing again. They are commonly used to treat heart disease and have helped many patients live better lives.

Etymology

The word stent comes from the name of Charles Thomas Stent, an English dentist who lived from 1807 to 1885. He improved a material called gutta-percha, which helped make better dental impressions.

Later, a Dutch doctor named Jan F. Esser used the name to describe a material that could support facial tissues during surgery. Over time, the idea of using a stent grew to include holding open blood vessels and other body passages.

History

The first use of a coronary stent happened in 1986 when doctors Jacques Puel and Ulrich Sigwart placed a stent in a patient in Toulouse, France. This stent acted like a scaffold to keep a blood vessel open and prevent a condition called restenosis, where scar tissue can grow inside the stent and block blood flow.

In 1993, the first stent approved by the FDA in the United States was created by doctors Cesare Gianturco and Gary Roubin. Later, in 2003, a new type called the drug-eluting stent was introduced to further reduce restenosis. Improvements and research on stents continue today.