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　　A T-shirt that constantly monitors the heart's activity and detects abnormalities could help protect people against stroke. The T-shirt, which can be washed up to 35 times before it needs replacing, has been developed to improve the detection of dangerous heart conditions like a trial fibrillation(心房颤动)，which causes an irregular heart rhythm and raises the risk of stroke.

　　At least one million people in Britain are known to have this condition; however, it's estimated that at least another 500,000 have it but haven't yet been diagnosed because they have no obvious symptoms. Some will have symptoms such as chest pain, dizziness and fatigue; but a large number of people have no idea they're ill until they suffer a stroke.

　　Detecting a trial fibrillation involves carrying out an ECG(心电图)。 Conventional ECGs are done in a hospital and involve highly trained teams of staff attaching up to 24 separate electrodes(电极) to different parts of the body to measure electrical signals. But most patients experience abnormal rhythms only intermittently(间歇性的). This means the chance of picking them up during a short hospital check is slim.

　　Doctors sometimes issue patients with a device called a Holter monitor to wear under their clothes to try to pick up cardiac (心脏的) problems. This is an electronic box which clips onto your waistband and is connected to a series of electrodes worn on the upper part of your body. But the box itself is quite bulky, hard to hide beneath clothing and involves a dozen or more wires being attached to the patient's chest.

　　The Cardioskin T-shirt, which is made from cotton, could be a much more convenient alternative and can be worn 24 hours a day-meaning it is more likely to pick up any abnormal rhythms in the patient's heart. It has 15 tiny electrodes woven into the material which are strategically placed around the chest area to track the electrical signals from the heart as they travel across the main part of your body.

The electrodes are powered by a battery which can be removed easily when you need to wash the T-shirt and feed results to a microchip which then sends them out