Word: aortas
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...world's leading centers for research in artificial heart aids. Last year its heart specialists pioneered in implanting temporary plastic ventricles (TIME, June 3, 1966). This time Dr. Adrian Kantrowitz and his colleagues had a new and simpler idea: to put a balloon in the aorta and make it serve as a pump. The balloon had an added attraction. It does not require major chest surgery on an already weakened patient...
Pumping on Signal. Surgeons injected a local anesthetic into the patient's thigh and cut into the femoral artery. They then threaded a flexible plastic tube up the artery and the aorta until a deflated balloon at its end was about level with the heart (see diagram). The outside end of the tube led to an electrically operated pump filled with nonflammable, nonexplosive helium. The patient was connected to an electrocardiograph, whose signals could control the pump...
With the balloon in place, the ECG signals were fed into a relay to regulate the pump's timing. When the patient's left ventricle contracted naturally, it sent a modest amount of blood into the aorta, but under insufficient pressure. A fraction of a second later, when her aortic valve had closed, the ECG signal made the pump fill the balloon with helium. This forced the blood in the aorta not only up and down, but also back to the roots of the coronary arteries, thus increasing the oxygen supply to the heart muscle. Meanwhile the ventricle...
...differs from most other vitamins in a second important respect: too much of it is as bad as too little. Severe or long-term excess causes chalky calcium deposits in arteries, notably the aorta, and in the kidneys, with stone formation and loss of kidney function. Eventually, this can be fatal. To guard...
Ironically, two more of nature's mistakes kept Betty going. There were two small holes in the septum (wall) between the two upper chambers of her heart, allowing partly oxygenated blood to pass through. And the ductus arteriosus, which supplies a normal and necessary connection between aorta and pulmonary artery during a baby's life in the womb, did not close as it should have after Betty's birth. This also helped to make partly oxygenated blood available to her faltering circulation...