Artificial Heart

Artificial Heart

The never ending pursuit of advancement by science and technology in its endeavor to ease the human life has been so tremendous that what we once thought was unfeasible is now a reality, such as in the creation of artificial organs. From an historic angle, no one would have ever imagined the possibility of providing a functional substitute for one of nature's creations. Since ancient times, people have viewed the heart as more than just a physical part of the living body. It has been thought as the seat of soul, the source of emotion and the center of each individual's existence. Scientist all over the world has spent many years to study the complex mechanism of the human body. Doctors and researchers have dedicated many years to the study of the heart, since they thought it was too delicate, too crucial to withstand the rigors of surgery. However, the innate human desire to strive for perfection has brought forth the invention of the artificial heart. Such an invention has literally changed the lives of many. According to the American heart association there are between 16,000 and 40,000 possible recipients of the artificial heart devices under the age of sixty-five.

The heart is one of the most important organs in the entire human body. It is a pump, comprised of muscle cells, which pumps blood throughout the body, beating approximately 72 times per minute. A heart is comprised of two pumps each with two chambers. The right-atrium pumps oxygen depleted blood from the body into the right ventricle, which in turn pumps it directly into the lungs - the left atrium sends aerated blood from the lungs into the left ventricle which pumps it out to the body. The heart

pumps the blood, which carries all the vital materials which help our bodies function and it removes the waste products that we do not need. For example, the brain requires oxygen and glucose, which, if not received continuously, will cause it to loose consciousness. Muscles need oxygen, glucose and amino acids, as well as the proper ratio of sodium, calcium and potassium salts in order to contract normally. The glands need sufficient supplies of raw materials from which to manufacture the specific secretions. If the heart ever ceases to pump blood the body begins to shut down and after a very short period of time will die.

Congestive heart failure, a steadily declining ability of the heart to pump blood, is one of the leading causes of death. This disease is caused by sudden damage from heart attacks, deterioration from viral infections, valve malfunctions, high blood pressure and other problems (Yambe, 282). People with heart problems experiences irregular heart beats that causes the heart to slow down disrupting the pumping of blood within their body. As time progresses, the heart gets weaker which calls for immediate treatment or surgery. Though medication and surgical techniques can help control symptoms, the only cure for heart failure is an organ transplant. In 1998, around 7,700 Americans were on the national heart transplant list but only 30% received transplants. Artificial hearts and pump-assist devices have thus been developed as potential alternatives (Yambe, 279-284).

An artificial heart is a prosthetic device that is implanted into the body to replace the original biological heart (Winfred, 557). The major function of an artificial heart is to

maintain the heart's blood circulation and oxygenation for varying periods of time. The ideal artificial heart must beat 100,000 times every 24 hours without lubrication or maintenance and must have a constant power source. Also, it must be able to pump faster or slower depending upon the activity of the patient without causing either infection or blood clots (Winfred, 556 - 557).

Unlike other cardiac devices the artificial heart provides the functions of both the heart and the lungs. This requirement is usually satisfied by transplanting a new heart from a donor who is of equal match to the recipient. Since the demand of a heart transplant is more than that of the donors, doctors and researcher's are forced to provide new methods and means by which the growing demands of these patients can be met. Having an artificial heart replaces the demand for more donors and hence provides an opportunity of hope for patients who are in critical need of a heart transplant.

Since the late nineteenth century scientists have been trying to develop a mechanical device that would emulate the functions of the human heart. The dilemma that has faced many of the scientists and researchers is to develop a device that would work continuously for long periods of time without any mechanical faults. As with any mechanical device there is a need of a generative power to continuously trigger the mechanism to perform its desired functions. From the moment it begins beating until the

moment it stops, the human heart works tirelessly. In an average lifetime, the heart beats more than two and a half billion times, without ever pausing to rest. Like a pumping

machine, the