Word: plastic
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...says, "one of the major problems is leaky valves. There wasn't much that surgery could do about it. So I went back to the beginning, and one of the answers, obviously, was to put in a substitute valve." Dr. Hufnagel soon designed an artificial valve containing a plastic ball float, and began trying it on dogs. It worked...
When several of the dogs had survived for two years or more with plastic valves and no ill effects, Georgetown sponsored Dr. Hufnagel's work and the U.S. Public Health Service helped with funds. The valve, as perfected, is made of Plexiglas and contains a float the size of a mothball which rises and slips into one of three sockets in the side of the valve sleeve on the heart's upbeat, when blood is forced into the aorta. When the heart relaxes between beats, the ball falls into a seat and stops blood from leaking back into...
...operation (under sodium pentothal and nitrous oxide anesthesia) lasted 2½ hours, most of that time was taken up in getting to the aorta. Then Dr. Hufnagel cut the aorta a few inches from the heart and fitted the loose ends of the aorta to the ends of the plastic valve sleeve. Like a plumber putting an extra valve in a water line, he left the old, defective valve in place. This part of the operation took only five minutes, and the blood flow to the brain was never interrupted...
Like a Watch. Dr. Hufnagel and his colleagues did not intend to publish the story of the operation until they had done it four or five times. It leaked out, anyway. They still cannot tell whether the plastic valve can be used in other types of heart disease. All they will say now is that they expect it to be a big help in many cases of damage to the aorta caused by rheumatic fever. (The exceptions: the very young, the feeble and the aged.) There are thousands of such cases in the U.S. each year...
...only patient now wearing an artificial aortic valve ticks like a watch to the stethoscopic ear. Like nature's valve, the plastic job will work equally well in any position. "Patients will be able to stand on their heads, if they like," says Dr. Hufnagel...