Cardiovascular Diseases (CVD)

It is one of the ironies of our society that people who rarely forget to fasten their seat belts, who scrupulously eliminate all known carcinogens from their diet, and who install sophisticated burglar alarm systems, may nevertheless take few precautions against cardiovascular disease (CVD), a class of highly preventable disorder that pose a severe threat to life, health, and well being.

According to the 1983 edition of Heart Facts, a booklet published by the American Heart Association, disease of the heart (cardio) and blood vessels (vascular) claim more American lives than all other causes of death combined. Cancer, which is for more widely feared, takes 400,000 lives in this country each year; but more than 1 million men, women, and children succumb to CVD annually. A stealthy killer that develops slowly and without noticeable symptom over a number of years, CVD takes many forms, including high blood pressure, coronary artery disease (disease of the arteries supplying the heart muscle), stroke, abnormal heart rhythms, and rheumatic heart disease. About 25,000 babies are born every year with hearth defects, and a stiffening total of 42.3 million Americans have some form of CVD. In all, heart and blood vessel disorders cost the nation $ 60 billion annually in medical expenses, lost wages, curtailed production, and lost labor.

Although CVD usually manifest itself during middle age, the seeds of the disorder seem to be sown decades earlier. In a now-famous study, army pathologist examined the hearts of 300 American soldiers who were killed in combat in Korea. These young men (their average age was twenty two) were apparently in good health when they were killed, and none were known to be suffering from heart disease at the time of death. Yet in more than 75 percent of the men, the coronary atherosclerotic process (a process in which coronary arteries are narrowed) bad already begun. As the study Cardiovascular Diseases can begin “silently,” while people are still in their late teens and twenty.

Artificial Heart

The first implantation of a permanent artificial heart in a human being took place in December 1982. The polyurethane and aluminum Jarvik-7 artificial heart, named for its designer, Dr. Robert K. Jarvik, was implanted by a surgical team led by Dr. William C. DeVries at the University of Utah Medical Center. The patient Dr. Barney Clark, was suffering from cardiomyopathy, a degeneration of heart muscles, and from respiratory problems. Although Clark developed many complications and died of circulatory collapse on Mar 23, 1983, the implantation was considered a success. The Jarvik-7 device, a bit larger than a human heart, consisted of two chambers that replaced the natural heart’s ventricles, or lower chambers, and was anchored to the patient’s atria, or upper chambers. It was powered by an air compressor outside of the body. Several modified Jarvik hearts were implanted thereafter, but the recipients suffered strokes and none lived longer than 620 days. Federal funding for the Jarvik project ceased in 1988, and implantations in the United States were restricted to temporary use until a real heart could be transplanted. In 1990 the Food and Drug Administration banned the device after a study of its effects on recipients concluded that the machine was doing more to endanger lives than to save them. Funding continues for research on fully implanted, electrically driven artificial hearts and on implantable pumps. Called ventricular assists, that do not require total heart replacement.

The first success in artificial heart research was achieved in 1957, when Drs. Willem Kolff and Tesuzu Akutsu of Cleveland Clinic implanted a device that kept a dog alive for 1 ½ hours. Researchers thereafter developed four-chambered hearts for temporary use in human beings; the first successful operation to implant such a device was performed by Dr. Denton A. Cooley in 1969.