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DeBakey did his first carotid endarterectomy in 1953. Ever since, he has been disappointed that the idea has been slow to catch on. One difficulty is that precise X-ray diagnosis, demanding great skill of the radiologist, is essential to show just which arteries are narrowed and where. Arteriography of this type is also highly uncomfortable, if not acutely painful, since the patients usually are fully conscious and only mildly sedated; partly because they must remain as cooperative as possible during the tests, partly to avoid the risks of anesthesia.
If only one of the four brainward arteries is involved, the operation is not too dangerous when done by skilled hands. But the risks increase if, as is often the case, two or even all four of the arteries are diseased. In any case, when an artery is exposed and clamped on each side of the diseased section, Dr. DeBakey has to slit it before deciding just what repair procedure will be best. It may be enough to ream out the atheromatous stuff from inside the artery. Afterward, however, simply to sew up the wound would make the artery narrower and increase the risk of a later shutdown. The reamed section must be made wider by stitching a patch of Dacron over the slit.
In many cases, the blood supply to the brain through other arteries is too tenuous for even one of them to be clamped shut for long. Then Dr. DeBakey has to install a temporary shunt of synthetic tubing while he works on the diseased section. If the blockage is too severe to be reamed out, DeBakey either leaves a permanent bypass in place or replaces the diseased section completely with a graft.
Up to the Arch. "Aneurysm," first used around A.D. 200, describes part of a vessel that has been "widened across." It remained buried in medical texts until DeBakey made it a household word. Aneurysms arise from two main causes: either an arteriosclerotic process, which weakens the artery wall, or a process by which two layers of the three-ply wall separate and blood forces them farther apart. Doctors call this second class "dissecting" aneurysms. Aneurysms are also classified by shape: saccular (like a bag) or fusiform (spindle-shaped). The saccular is likely to be on only one side of an artery, while the dissecting is usually fusiform and surrounds it.
Beginning in 1949, Dr. DeBakey diagnosed many aneurysms among aged veterans and charity patients—but usually at autopsy, for the disease was almost always fatal. Working with Dr. Denton A. Cooley, DeBakey decided that something could be done about the problem if the artery could be strengthened with a synthetic wrapping—or, better still, cut out and replaced. Freeze-dried calves' arteries and segments of human arteries taken from accident victims were tried, but grafts of Dacron tubing proved to be the answer.
Steadily, the Baylor surgeons worked their way up from simpler and more accessible aneurysms in the abdominal cavity. The advent of the heart-lung machine had the same stimulating effect on aneurysm surgery as it had on arterial obstructions: it made possible the removal of diseased sections of the aorta in the chest cavity, in and around the aortic arch, near where the arteries branch off to the arms and head. The Duke of Windsor's case was typical of the more manageable abdominal type, although his aneurysm proved to be larger than expected.