I. Electric Total Artificial Heart
II. Left Ventricular Assist Device
III. Is There a Logical Role for Ventricular Assist Devices?
IV. New Frontiers
GLOSSARY
atherosclerosis same as atheroma, raised plaques filled with cholesterol, calcium, and other substances on the inner wall of arteries that obstruct the lumen and the flow blood; the plaque of atheroma hardens the artery, hence the term atherosclerosis (sclerosis ¼ hardening).
heart failure a failure of the heart to pump sufficient blood from the chambers into the aorta; inadequate supply of blood reaches organs and tissues.
left ventricular assist device a device that can replace a left ventricle that is no longer able to pump blood into the aorta.
New York Heart Association class IV heart failure the worst stage, end-stage, severely symptomatic at rest.
thromboembolic clots or thrombi that break off from the interior lining of the heart; they are propelled by the blood and become lodged in an artery supplying blood to an organ or to the extremities.
CARDIOVASCULAR DISEASE IS THE MAIN CAUSE of death in the United States, Canada, UK, Ireland, and Europe. It accounts for more than 40% of total deaths in these countries. Many of these deaths are due to heart failure. Heart failure affects approximately five million Americans with more than half a million new cases diag¬nosed annually. The aggregate five-year survival rate of patients with heart failure is approximately 50%, but the one-year mortality rate is close to 50% for patients with severe heart failure (New York Heart Association class IV heart failure). Patients who remain in class IV heart failure for several months despite optimal medical therapy may require heart transplantation.

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• I. ELECTRIC TOTAL ARTIFICIAL HEART
  The first artificial heart implant was carried out by Dr. Denton Cooley in Houston, Texas, in a 47-year-old man with intractable heart failure using the Liotta artificial heart developed by Domingo Liotta. This artificial heart was based upon the laboratory work of Dr. Michael DeBakey.
• II. LEFT VENTRICULAR ASSIST DEVICE A. Systems
  Left ventricular assist devices are implanted only in patients who are eligible for cardiac transplantation. These devices are used as bridges to transplantation. There are three left ventricular assist devices presently available:
• III. IS THERE A LOGICAL ROLE FOR VENTRICULAR ASSIST DEVICES?
  There are approximately fewer than 3000 donor organs available worldwide per year. In the United States alone, in 1999, 2184 patients with heart failure underwent heart transplantation. When a left ventricular assist device is implanted a donor heart must be available within approxi¬mately 3 months for the patient to maintain survival and quality of life.
• IV. NEW FRONTIERS
  A ray of hope has been generated by the work of Dr. M. H. Yacoub, who describes a novel strategy: a com¬bination of surgery and physiologic hypertrophy. The surgical process involves implantation of a left ventricular assist device and medical therapy with a drug, clenbuterol, a beta-2-agonist which induces reverse remodeling of the left ventricular myocardium and subsequent physiologic myocardial hypertrophy. This strategy improves left ven¬tricular contractility and ejection fraction sufficiently to allow explantation of the assist device (the Harefield protocol).
• BIBLIOGRAPHY
  Brown, B. G., Crowley, J. et al. Is there any hope for vitamin E? JAMA,