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1. INTRODUCTION
Many people suffer from heart disease. Some of the diagnosed cases are so severe that patients may not survive the wait for a donor heart. There are many devices that are available such as such as pacemakers and artificial hearts to keep patients alive until a donor heart is becomes available. Like all machines the heart can malfunction in numerous ways. Many conditions fall under the category of cardio vascular disease; but two main causes for heart transplantation and artificial hearts: coronary heart disease and congestive heart failure .The development of the artificial hearts reflects a transition from a support device to a completely self contained machine. In the 1960s the purpose of an artificial heart was for to temporarily support patients until a donor heart became available. Surgeons attempted to change this role in the early 1980s by implanting an artificial heart intended for long term therapy. The device they used was the Abiocor, a blood pump the heart ventricles. Although this procedure was successful, the surgeons became wary of this device as it did not provide an acceptable quality of life .As a result the public began to question the need for removing vital components of the heart .The world of artificial heart was then separated into two classes; assist devices & artificial hearts.
In the 1980s the organizations involved in making new designs for the artificial heart encountered one major problem, infection due to percutaneous or skin piercing tubes as every artificial heart has power cord, blood tubes or air tubes protruding from the skin .It was not until the early 1990s with the advent of transcutaneous technology that progression to permanent devices became more feasible. Today the role of artificial hearts has extended from temporarily bridging a patient to transplantation to providing long term assistance.
2. NEED FOR ARTIFICIAL HEART
The two main causes for heart transplantation and artificial hearts are coronary heart disease and congestive heart failure. Coronary heart disease (CHD) is the hardening of artery walls inside the heart .Arteries are essentially piping that connects heart valves together. In CHD, the transportation of blood becomes when a mixture of fat and cholesterol, or plaque, lines the arteries. The buildup of plaque restricts the free flow of blood, which induces a pressure drop between the valves. The heart compensates for this pressure drop by pumping harder in order to provide blood for the entire for the entire body. Patients suffering from CHD often exhibit symptoms such as severe chest pain and fatigue due to the lack of oxygenated blood. For severe cases of CHD, the only cure is a heart transplant. Congestive heart failure (CHF) arises when the heart does not efficiently pump blood .Since the heart is unable to pump enough oxygen rich blood, blood starts filling in the lungs, which leads to congestion. Therefore, the heart must work harder to meet the body’s oxygen demands. This behavior causes excessive wear of the diseased organ. Initial symptoms of CHF, such as fatigue and swelling of the ankles are usually so minor that the patients are not diagnosed until the condition becomes much more severe.
Further lack of organ donors, and availability at the right time justified the research in this field.
3. WORKING OF HUMAN HEART
The human heart pumps 10,000 liters of blood per day. Deoxygenated blood flows from the rest of the body to the right atrium. Oxygenated blood flows from the lungs to the left atrium. Deoxygenated blood flows from the right ventricle to the lungs. Oxygenated blood flows from the left ventricle to the rest of the body.
The human heart is divided into four chambers:
1. Right Atrium
2. Right Ventricle
3. Left Atrium
4. Left ventricle
The heart contracts in two stages:
1. In the first stage, the right and left atria contract at the same time, pumping blood to the right and left ventricles.
2. In the second stage, the ventricles contract together to propel blood out of the heart.
4. MILESTONES IN ARTFICIAL HEART TECHNOLOGY

1960 - Surgeon implants first temporary artificial heart.
1970 -Engineers develop the ventricle assist devices as an alternative to artificial hearts
1980 - First long term artificial hearts lead to poor quality of life.
- VAD show potential for long term support
1990 -Transcutaneous technology eliminates need for skin protruding electrical wiring
- Patients with long term VAD recover from heart failure.
2000- Results of the abiocor reflect improved quality of life for patients after implantation