At the moment this has not gone any further than the laboratory, but it is an innovative concept

Professor Gianni Angelini

The problem occurs when heart disease has blocked the blood vessels which supply oxygen to the muscles of the heart itself.

Sections of a blood vessel from elsewhere in the body, such as the chest or the leg, are taken and used to replace the clogged up coronary arteries.

However, stitching the graft to the heart's blood vessels is a very delicate task.

Patients are usually given an anti-clotting drug following the surgery, and this can lead to leakage from the stitch marks.

Simplified

The new device should make the procedure considerably more simple - and cheaper for the NHS.

Stitching of a conventional graft takes between six and ten minutes. The new device should cut that down to 90 seconds.

Surgeons insert the tube into the main body of the coronary artery.

Once in place a retractable extension is slowly pulled out so that it sticks out of the artery, and can be used to attach the graft vessel, which is held in place with a sealing ring.

The device has been developed by Tony Anson, of Anson Medical, now part of Lombard Medical Group, in collaboration with Professor Gianni Angelini, of the Bristol Heart Institute.

It is expected to be tested in clinical trials within the next two years. However, it is unlikely to be made widely available for at least five years.

At present, bypass surgery is a major operation which involves opening up the chest.

However, Professor Angelini told BBC News Online that if the device proves its worth in clinical trials, it could lead to the operation being done using keyhole techniques.

He said: "At the moment this has not gone any further than the laboratory, but it is an innovative concept.

"The idea is to make surgery much speedier, and less prone to surgeon mistake.

"Bypass surgery can be done using keyhole techniques at the moment, but it is a bit like sending rocket to the moon."