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• Definition
• History
• Advantages/Disadvantages
• Anatomy of the heart
• Causes of heart failures
• Statistics
• Current developments
• Future advancements
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It is a mechanical device that replaces the functionality of a natural heart and is designed such that it is biocompatible among other organs and the immune system and is quite able to associate with and respond to the natural demands of the body due to homeostatic imbalances.
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The design ofperfusion pump
by Dr. AlexisCarrel and CharlesLindbergh in 1935
In 1957 the first completelyartificial heart was
implantedin a dog by Dr. William Kolff
at Cleveland Clinic
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In 1966, Dr. Michael DeBakey designed an air pressure driven device called Left Ventricular
Assist Device to assist the left ventricle of the heart to
pump blood into the arteries
Dr. Domnigo Liotta from Argentina developed the first implantable artificial heart
for human and performed the surgery in 1969
The Timeline of Development
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In 1982, American physician Robert
Jervik develops the Jervik-7, which kept its first recipient for
102 days
In the late 90’s, SynCardiaInc implements the
modified and enhanced redesign of Jervik-7 and
calls it CardioWest
In 2001, AbioMed Co. develops the most advanced
electromechanical artificial heart known to date in the 21st
century
Name: The perfusion pump
Developers: Dr. Alexis Carrel and Dr. Charles
Lindbergh
Description: Externally set up and pneumatically
driven (air pressure) pump
designed to keep the patient alive
until a donor becomes available
Name: The Jervik 7
Developer: Dr. Robert Jarvik
Description: Made of plastic and titanium and
powered by compressed air. It
was also designed for temporary use until a donor becomes available.
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Name: CardioWest
Manufacturer: SynCardia Systems Inc.
Description: Biventricular, air pressure driven total replacement of natural heart . Not self sustained but have been very successful in keeping patients alive for a long time till donor becomes available.
Name: AbioCor Artificial Heart
Manufacturer: Massachusetts-based company Abiomed
Description: The first completely self contained
artificial replacement heart designed to run on external transmitted power and perform cardiac functions
Positive Outcomes—• Artificial hearts with portable control systems gives
the patient opportunity to be mobile and participate in their daily activities
• Artificial hearts are always available and can save a heart patient’s life during his/her critical time
• New researches are being done to improve the functionality of artificial hearts so that they can obtain and sustain energy from oxygenated blood
• Developmental research firms estimates that more than 100,000 people in the U.S. could benefit from the artificial hearts each year
• Latest models such as AbioCor artificial heart can increase and decrease pumping rate according to body’s need
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Issues that yet remain— Artificial hearts are still not completely responsive
to physiological homeostatic changes of the body
At risk of wearing out in the body or being rejected by other organs of the body
At risk of causing infection if the batteries get exposed to the internal environment of the body
Artificial hearts cannot produce energy from the oxygenated blood; therefore, external power source is required to consistently recharge the batteries
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Ascending aorta
Pulmonary Trunk
Right atrium
Right ventricle
Inferior vena cava
Superior vena cava
Right pulmonary artery
Left pulmonary artery
ANTERIOR VIEW
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POSTERIOR VIEWLeft common carotid arteryLeft subclavian
artery
Ascending aorta
BrachiocephalicTrunk
Descending aorta
Left pulmonary veins
Right pulmonary veinsLeft Atrium
Left Ventricle
• Coronary artery disease and heart attack:
most common disease lead by atherosclerosis—blockade of arteries and veins with fat and plaques
• Myocarditis:
viral or bacterial infection of the cardiac muscle
• Cardiac Arrhythmia:
abnormal pulse rate due to abnormal nerve conduction
• High blood pressure (hypertension):
increased blood volume and flow cause enlargement of the heart restricts active function of the heart
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• “According to American Heart Association investigation, about 4,000 patients in the United States are waiting for a heart transplant at any given time but about 2,300 donor hearts become available each year.”
• It is estimated that about 250 - 500,000 people in the United States, and approximately 2.2 million people globally are diagnosed with heart problems yearly.
• Heart failure cause over half of all deaths of people over 45.
• Congestive heart failure affects 200 000 to 300 000 people in Canada annually. Furthermore, since 1970 the death rate from CHF has increased by 60%, and the current 5-year survival rate is only 62%
• About 260,000 deaths a year occur in U.S. Population due to heart conditions.
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3 extreme conditions::::
The damage to the heart is extremely
severe and no other treatment is available
There is no donor for a live heart
transplant
Only technology is the last hope to save a life
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Hydraulic pump: Located in the heart. There is a gear inside that spins at 10000 rpm to generate pressure and force blood out to lungs and body.
Porting Valves: They open and close to let blood out to lungs first and then to the body.
Wireless Energy Transfer System: AKA Transcutaneous Energy Transfer (TET), consists of two coils that transmit power via magnetic force from the external battery.
Internal Battery: Rechargeable unit that gives patient 30 - 40 minute time toperform any water works (i,e, showering)
External Battery: Wearable outside that transfers electric energy over the skin.
Controller: Monitors and controls the pumping speed of the heart.
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Requirements: a) Must imitate the natural heartb) Must be placed in proper locationc) All the atriums and valve connections must be
made accurately
Natural Heart Features: a) On average beats at 60 – 100 beat/min
b) Works in 2 stages – left and right atriums contract together to draw blood in, ventricles contract together to pump blood out.
c) Cardiac muscle relaxes for the heart to fill up with blood before the next beat
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AbioCor Artificial Heart Features:
a) Able to pump more than 10 L/min which is enough for daily activities.
b) Replaces both the ventricles with a single pumping unit; therefore only pumps blood outone ventricle at a time
c) Hydraulic pump is the sophisticated device that shuttles fluid from one side to another side
d) Sends blood first to lungs and then to the rest of the body.
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The Recipients of AbioCor
Robert Tools (in the middle)
The first AbioCor Artificial heart recipient. Surgery performed by Dr. Gray (left) and Dr. Dowling (right). He lived for 5 months after the operation.
Tom Christerson (in the middle)
The second AbioCor Artificial heart recipient. Surgery done by the same doctors. He lived 17 months after the operation.
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-Modern version of the Jarvik-7
-It is a temporary biventricular device that runs on external drivers
-Currently used as a bridge to transplant
-Able to pump up to 9.5 L/min-It weights 160 gram
-Imitates exactly the pumping function of the natural heart
-It is air pressure driven. Air pressure is produced in the driver
-It is made of synthetic polymer, especially polyurethane
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CardioWest Functionalities
- CardioWest functions on generated air pressure
- An artificial heart beat is generated from the external driver through air suction and air blow in to the ventricles
- When the air is sucked out externally, the pressure causes the ventricles to draw blood in from the atria and the vena cava(s)
- When air is pushed in externally, the ventricles contract and force blood out through aorta and pulmonary artery
- The system needs to be connected to an external control system. This requires connection through the skin.
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Goals:
Understanding the nature of cardiac muscle cells and developing artificial self sustained cardiac muscle cells
Designing a procedure to put individual cardiac cells together and develop a functional 3D muscle unit
Develop models of cell based cardiac pumps that simulate the functions of ventricles.
Mimic the natural energy transfer system of the cardiac muscle at cellular level
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Research Institution: University of Michigan
Research Interest: Functional Cardiovascular Tissue Engineering
Research Facility: Biomedical Science Research Building
Research Projects
Implementation of 3D Heart muscles in vitro— (3 models)1. Based on cell division process of primary cardiac myocytes2. Based on utilization of biodegradable fibrin gel3. Based on utilization of polymeric scaffolds
Phenotypic Modulation—1. Utilization of chemical, mechanical and electrical stimulation to generate
contractility in cardiac muscle 2. Significant improvement is found in contractile performance of cardioids using
tryroid hormones
Cell Based Cardiac Pumps—1. Artificial pumps consisting of lumunal tubular scaffold fabricated from polymeric material capable of hydrostatic pressure upon electrical stimulation
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HeartMate™ LVASA heart assist device. Implantable alongside the native heart and designed to assist the pumping function of the heart's left ventricle
Novacor® LVASwearable system that provides pulsatilecirculatory support for patients with life-threatening heart failure.
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Manufacturing Company:Ventracor
Manufacturing Location: Australia
Features:
- Uses hydrodynamic levitationof the blood cells
-Contains hydrodynamic impeller
-Simple design and light weight
-Outstanding biocompatibility
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http://www.discoveriesinmedicine.com/ApgBan/Artificial-Heart.html
http://www.syncardia.com/newsroom/Tour_112305.php
http://dsc.discovery.com/news/2006/09/06/artificialheart_hea_zoom0.html?category=health&guid=20060906160030
http://eduspace.free.fr/vs_pages/bionic_heart.htm
http://med.stanford.edu/school/vascular
http://www.fi.edu/learn/heart/healthy/fake.html
http://www.chfpatients.com/text/VAD_overview.txt
http://www2.healthcare.ucla.edu/artificial_heart/pressbroll.html
http://heart.health.ivillage.com/heartfailure/totalartificialheart.cfm
http://www.technologyreview.com/read_article.aspx?id=17523&ch=biotech
http://www.sitemaker.umich.edu/ahl/welcome_
Directed ByArefin Shamsil
Dino Sia
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