ENGLISH ORAL-THE BEST INVENTION OF THE PAST CENTURY.
How often do you stop to think about the rate of your heartbeat? Do ever worry that your heart may be beating too fast or too slow? I"m sure that fears of heart problems are not even present in your mind. But for hundreds of millions of people world wide, these fears have been realized, and have had a profound and devastating effect on their lives and the lives of their families. Patients can perhaps consider heart transplant waiting lists or risk open-heart surgery. The majority, however, have no options.
However, in the 1950's a revolutionary way to treat heart problems was introduced. This was the pacemaker. A pacemaker is a battery-operated device that can replace your natural heart pacemaker. Ultimately, the pacemaker stimulates and regulates the heart muscle contractions. .
The external pacemaker, first used in the 1950's, was not widely popular as its extension cord only allowed limited movement and power failure was a constant problem. Then in 1957, the world's first battery powered pacemaker was developed. This gave patients mobility and eliminated concerns about power failure. A fully implanted pacemaker was used from 1960, however its battery life was only between 12 and 18 months. This was developed along with the "demand" pacemaker, which could detect changes in heart rate itself, and provide pacing only when necessary. Eventually the battery life was extended on some models to over 10 years. Programmable pacemakers were introduced in 1979. These were extremely successful as their settings could be programmed or adjusted using radio frequency. This innovation eliminated the need for surgery were pacemakers were concerned. Now, pacemakers operate like microcomputers, are half the size of the original model and last much longer.
Pacemakers make heart surgery unnecessary in numerous cases, which, in turn, dramatically improve the patient's chance of survival and life expectancy.
Take for the example, the invention of the cardiac pacemaker. ... McWilliam, from the United Kingdom, thought with the idea for a pacemaker. Although he was the person who thought of the idea, Earl Bakken, from the United States, was the first to develop an externally wearable pacemaker. Then, from the advancements made by Bakken, Rune Elmqvist and Ake Senning, from Sweden, were able to design the first implantable pacemaker. ...
The chronotropic state of the heart is regulated by the Sino Atrial Node (SAN) or pacemaker, the inotropic condition of the heart is dependant on the contractility of the myocardium. ... The increased intracellular potassium hyperpolarizes the membrane potential and slows the repolarisation of the pacemaker potential, making the time period between action potentials greater and the heart rate falls. ... The sympathetic innervation of the heart increases the slope of the pacemaker potential, this produces a faster heart rate as the SAN pacemaker cells can reach the threshold for the actio...
Radionuclide batteries used in pacemakers use Pu-238, while Pu-239 is used in reactors and for Nuclear weapons. ... The three major advantages to using this element are for an energy source, power for nuclear propulsion in space exploration and thermo-electric generators in cardiac pacemakers. ... The last beneficial use for plutonium is for cardiac pacemakers. The thermo- electric generator which is powered by radionuclide batteries that powers the pacemaker uses Pu-238. ...
(ref. 13) Radionuclide batteries used in pacemakers use Pu-238, while Pu-239 is used in reactors and for Nuclear weapons.... The three major advantages to using this element are for an energy source, power for nuclear propulsion in space exploration and thermo-electric generators in cardiac pacemakers. ... (ref. 3) The last beneficial use for plutonium is for cardiac pacemakers. The thermo-electric generator which is powered by radionuclide batteries that powers the pacemaker uses Pu-238. ...
(ref. 13) Radionuclide batteries used in pacemakers use Pu-238, while Pu-239 is used in reactors and for Nuclear weapons.... The three major advantages to using this element are for an energy source, power for nuclear propulsion in space exploration and thermo-electric generators in cardiac pacemakers. ... (ref. 3) The last beneficial use for plutonium is for cardiac pacemakers. The thermo-electric generator which is powered by radionuclide batteries that powers the pacemaker uses Pu-238. ...
Arrhythmias Introduction Nearly everyone has felt their heart "skip a beat" or beat too slowly. Occasional heart palpitations are common and harmless, and can be caused by anything alcohol to staying up too late. These kind of palpitations don't require medical treatment, but recur...
(ref. 13) Radionuclide batteries used in pacemakers use Pu-238, while Pu-239 is used in reactors and for Nuclear weapons.... The three major advantages to using this element are for an energy source, power for nuclear propulsion in space exploration and thermo-electric generators in cardiac pacemakers. ... (ref. 3) The last beneficial use for plutonium is for cardiac pacemakers. The thermo-electric generator which is powered by radionuclide batteries that powers the pacemaker uses Pu-238. ...