Medical First: Heart Valve Replacement Without Surgery

      PARIS, Oct 20 (AFP) - French doctors have carried out the first replacement of a cardiac valve without resorting to open-heart surgery, The Lancet reports in Saturday''s issue.

      A team led by Daniel Sidi of the Necker Hospital in Paris said the operation was carried out on a 12-year-old boy with a chronic blockage of the valve supplying his pulmonary artery, which transports blood to the lungs.

      Normally, valve replacement is a long and complex operation in which the chest is opened up and the defective tissue replaced with a prosthesis or a valve from an animal, such as a pig or cow.

      The problem is that the replacements themselves usually have to be replaced every five to 10 years, requiring patients to undergo the trauma of another operation.

      The solution adopted by the Paris team was literally to plug in a valve replacement by inserting it from outside the body, using a catheter.

      The valve, taken from a bovine jugular, was mounted on a stent -- an ultra-thin, tiny cylinder of platinum mesh that is commonly inserted into major blood vessels to support a weakened vessel wall.

      The valve and stent were put on the end of the catheter, which was then inserted into the femoral vein in the groin and gently pushed up to and across the heart, to the area of obstruction.

      "The end of the catheter then inflated like a balloon, opening out the valved stent and setting it in place," the inventor of the technique, Philipp Bonhoeffer, told AFP.

      The team practised the valved stent on lambs before trying it on the child, who is in good health and has no problems with the flowback of blood into the heart, which occurred with his old valve, the study says.

      The advantage of catheter insertion is that it is non-invasive, a particular boon for children who have to undergo traumatic surgery, Bonhoeffer said.

      When the new valve eventually wears out, a replacement one of slightly smaller diameter can be slotted into place underneath it, he said.

      That could be repeated three or four times before surgery is needed, it is hoped.

      PhC-ri/ss

     

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