Can the Artificial Heart Replace the Real Thing? : Can the Artificial Heart Replace the Real Thing? By: Kyle Walker
11/29/10 Human Heart “real thing” : Human Heart “real thing” The heart begins to beat 4 weeks after conception & doesn’t stop until death.
An adult heart can pump up to 2,000 gallons of blood each day which is roughly 5 quarts of blood a minute.
It is capable of beating over 100,000 times a day.
It will beat over 2.5 billion times in the average life span of 70 years.
The heart consists of 4 chambers a right & left atrium as well as a right & left ventricles
Both the right and left atrium hold about 3.5 tablespoons of blood where the right ventricle can hold about a quarter cup of blood.
The left atrium is about three times thicker than the right. Heart Function : Heart Function 1: When the heart is at rest the right atria is filled with oxygen free blood returning from the body. While the left atrium receives oxygen rich blood from the lungs.
2: After the atria fill an electrical impulse causes them to contract forcing open valves that lead to the ventricles.
3: The same electrical impulse causes the ventricles to contract about a tenth of a second later pushing the blood through another set of valves that lead to the lungs and the rest of the body.
4:The ventricle relax causing the valves to snap shut which causes the dub sound in the heartbeat. This allows the atria to fill with blood and the process repeats itself. Need for Artificial Heart : Need for Artificial Heart Heart disease is the number one cause of death for both men and women in the United States
Currently 17 million people die from heart disease each year.
It’s estimated that 20,000 people worldwide are in vital need of a transplant each year.
Over 25% of patients waiting for a transplant die before they can receive an organ. History : History 1972- Robert Jarvik created the 1st human artificial heart made of polyester, plastic, & aluminum. It was implanted in cows.
1981- The 1st artificial heart was approved for human implantation. (Jarvik-7)
1982- Barney Clark received the 1st implantation performed by William DeVires of the University of Utah.
1994- The FDA approved the Ventricular Assist Device (VAD) which was the 1st wearable device to assist the left ventricular
2004- The 1st Total Artificial Heart (TAH) was approved by the FDA by CardioWest. Jarvik-7 Artificial Heart : Jarvik-7 Artificial Heart The Jarvik-7 design incorporates two heart pumps that are connected to a power console.
Each pump is small enough to be implanted into the void that was left behind from the extraction.
Both pumps receive power from a large external console. The console pushes air through the tubing.
Air enters inside the pump and is expelled through a series of thin flexible diaphragms.
The doctors monitor the patients cardiac output and heart rate from a power console a seven feet away from where the patient rests. Jarvik-7 Artificial Heart : Jarvik-7 Artificial Heart Left Ventricular Assist Device : Left Ventricular Assist Device The Left Ventricular Assist Device is a portable device.
There are two insertion points the inflow at the apex of the left ventricle. The outflow is connected with the ascending aorta.
The left side of the heart receives blood from the lungs. It then exits out the left ventricular apex and through an inflow valve that enters the pumping chamber.
Once in the chamber the blood actively pumped through an outflow valve that enters the ascending aorta.
The electrical cable and air vent that are connected to the pump lead out the skin. They are attached to electrical controls and a battery pack which can be worn by the patient. Left Ventricular Assist Device : Left Ventricular Assist Device Total Artificial Heart : Total Artificial Heart The heart pump is implanted by surgeons where the ventricles where removed.
The channels that connect naturally to the ventricles are sewn into artificial cuffs that are connected to the heart.
The are two independent hydraulic motors are embedded in the heart. One motor is used to maintain a constant pumping action. The other motor is responsible for controlling the motion of the four heart valves.
An electrical coil is implanted in the abdomen area to allow for recharging across the skin.
A battery pack that can be worn by the patient supplies the device with power throughout the day.
There is also an internal battery which allows for the patient to bath themselves.
The artificial heart is made with very smooth plastics which allows for constant motion of blood cells. This is important because any blood that stops on the surface material has a high potential of clotting. How Artificial Heart Functions : How Artificial Heart Functions References : References Crumley, Bruce. "Can an Artificial Heart Replace the Real Thing?" Time 07 Dec. 2008. Web. 10 Oct. 2010.Hajar, Rachel.
"The Artificial Heart." History of Medicine 08.02 (2006): 70-76. Web. 07 Nov. 2010."Heart, Front View: MedlinePlus Medical Encyclopedia Image.
" National Library of Medicine - National Institutes of Health. Web. 06 Nov. 2010. <http://www.nlm.nih.gov/medlineplus/ency/imagepages/1097.htm>.
"YouTube - Animation: Total Artificial Heart Beating in Patient's Chest." YouTube - Broadcast Yourself. Web. 27 Nov. 2010. <http://www.youtube.com/watch?v=h4-vZTW5O94>."YouTube - Artificial Heart Animation.
" YouTube - Broadcast Yourself. Web. 07 Nov. 2010. <http://www.youtube.com/watch?v=oHvIwkYRFV4&NR=1>.
"YouTube - Narayana Hrudayalaya - LVAD - Artificial Heart." YouTube - Broadcast Yourself. Web. 26 Nov. 2010. <http://www.youtube.com/watch?v=M8fkMX99G5E>.