A team of UK scientists have successfully used stem cells to grow tissue that works like a heart valve in the laboratory.

Sir Magdi Yacoub, a world famous heart surgeon based at Imperial College London, and a multidisciplinary team of scientists have been working for the last ten years at Harefield Hospital in London to address the problem of too few donor hearts for transplant operations.

They intend to take the research further and try to grow a complete heart. when asked how long that would take Sir Magdi said while it was an ambitious project it was not impossible and if forced to give a timescale he would say ten years.

Other scientists, while welcoming the news are cautiously saying it is still early days and will be several years before something that works in the lab is proven to work in living animals.

Sir Magdi and his team, which included physicists, pharmacologists, cellular and clincal scientists, developed the heart valve cells by taking adult stem cells from bone marrow. They used collagen, a protein of great tensile strength and ideal as “scaffolding” for tissue growth, to hold the valve tissue in shape as it grew into one-inch disc-shaped valves.

Plastic heart valves do exist and every year in the UK thousands of people have operations to replace faulty heart valves.

However, there are several problems with artificial heart valves. One of them is that you have to keep taking drugs to stop the body rejecting the foreign material in the heart. This is the same with transplanted heart valves.

British Heart Foundation Professor John Martin said that the stem cell method has two advantages for patients:

“Firstly the tissue produced in the laboratory might be used instead of putting the patient through a heart transplant. Secondly, because the patient’s own stem cells are used it eliminates the problem with rejection that happens when a heart has been donated by another person.”

Also, according to Sir Magdi, a valve grown from stem cells would be more sophisticated than a simple artificial valve that just opens and shuts. It would operate more like a real heart valve that anticipates what the blood flow is going to be and acts accordingly.

Sir Magdi’s team are scheduling trials in animals later this year. If successful, it could mean stem cell grown heart valves being used in transplants within three years, they said.

This is the first time that part of a complex organ has been grown using stem cells. Other tissue parts and simpler organs such as tendons, bladders, cartilage have been successfully grown from stem cells.

There are several types of heart valve that regulate the flow of blood through the heart. They can go wrong in many different ways, either from inherited or acquired diseases. They can become inflamed (endocarditis) they can prolapse, fail to open and shut properly (causing regurgitation or flow in the wrong direction), they can leak and they can narrow (stenosis).

Click here for patient information on Valvular Heart Disease (British Heart Foundation).

Written by: Catharine Paddock
Writer: Medical News Today