Steps to speed bypass surgery

Heart surgeons are trying to find less invasive ways of carrying out operations

Innovations to speed up heart bypass surgery are promising a safer future for patients, say engineers.

The latest progress of two inventions is being unveiled at a scientific meeting in the US on Monday.

It is hoped that eventually it will become far easier to carry out heart bypasses without having to open the chest cavity, stop the heart and put the patient on a heart-lung machine to keep him or her alive.

Patients need coronary bypass grafts when heart disease has blocked the blood vessels which supply oxygen to the muscles of the heart itself.

Delicate task

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

Stitching on the new blood vessels is a delicate task, and many surgeons still choose to stop the beating of the heart to carry it out.

All of these take us one step nearer, because they potentially make these operations quicker and easier for surgeons to do

Mr Rex Stanridge,
St Mary's Hospital, London

However, artificially recreating the pumping of the blood with a machine outside the body is thought to worsen the results, with the possibility of heart damage and cerebral problems following the operation.

More and more surgeons now choose to carry this operation out while the heart is still beating - restricting its movement with special clamps.

The first invention, under trial in the University Hospital of Berne, Switzerland, could make this easier.

It is a clip which hooks the new section of vein into its new position against the coronary artery.

Where previously a surgeon would have had to apply stitches to make the join, the clip allows connection in less than two minutes.

Successful tests

Dr Friedrich Eckstein, who is leading the project, has tried it out on 13 patients, although its experimental nature meant that these were not "beating heart" operations.

His results, revealed at the American Heart Association's Scientific Sessions 2001 conference, showed that all the procedures went well, and the amount of time on the heart-lung machine was reduced.

"The sutureless technique permits a more consistent connection between the blood vessels and could be used in bypass operations without a heart-lung machine or even in minimally-invasive coronary surgery."

The other technique, so far tested only on pigs, uses an adhesive to glue the two blood vessels together.

Dr Marc Buijsrogge, from the University Medical Center in Utrecht, Netherlands, told the meeting that 35 days after surgery, all his connections were still firmly in place.

These operations were carried out while the pig heart was still beating, he said.

Robots - the next step

Mr Rex Stanbridge, a consultant cardiothoracic surgeon from St Mary's Hospital in London, told BBC News Online that all these innovations, and others like them, might eventually be harnessed by surgeons carrying out keyhole heart bypass operations using robotic equipment.

He said: "All of these take us one step nearer, because they potentially make these operations quicker and easier for surgeons to do.

"Other projects which have excited me are a suture which is far easier to tie, because it automatically forms itself into a knot, and a way of joining blood vessels using magnets."

The St Mary's team is currently trying to develop robotic beating heart surgery further - worldwide it has been tried on a number of patients who need just a single coronary artery graft, and fewer who need two.

Most people who need grafts need at least three arteries replaced , but robot-assisted surgery like this has not yet been completed successfully in humans.