Artificial heart.pptx

Artificial organ- any machine, device, or other material that is used to replace the functions of a faulty or missing organ or other part of the human body

The devices are human-made, whereas the living replacement parts can be obtained from the patient, a relative, a human cadaver, or a live animal or can be prospectively developed through genetic engineering.

The concept that a disease state may be addressed not only by returning the malfunctioning organ to health using chemical agents or physical means but also by replacing the missing function with a natural or an artificial counterpart has brought about a revolution in therapeutics.

It is considerably more effective than drug therapy or corrective surgery in the treatment of many conditions, e.g., cardiac valve disease, heart block, malignant arrhythmia, arterial obstruction, cataract.

Artificial organs can be located outside of the body yet attached to it (paracorporeal prostheses or assist devices) or implanted inside the body in a appropriate location (internal artificial organs or implants).
The application of artificial organs may be temporary, i.e., a bridge procedure to sustain life or a specific biologic activity while waiting for either recovery of natural function (e.g., the heart-lung machine), or permanent organ replacement (e.g., left ventricular assist devices).

1. ARTIFICIAL HEART, ARTIFICIAL VENTRICULAR DEVICES PRESENTED BY: ELIZABETH PHILIP BIOLOGICALLY INSPIRED ARTIFICIAL DEVICES

2. INTRODUCTION A rtificial organs can be located outside of the body yet attached to it ( paracorporeal prostheses or assist devices) or implanted inside the body in a appropriate location (internal artificial organs or implants). The application of artificial organs may be temporary, i.e., a bridge procedure to sustain life or a specific biologic activity while waiting for either recovery of natural function (e.g., the heart-lung machine), or permanent organ replacement (e.g., left ventricular assist devices). A rtificial organ - any machine, device, or other material that is used to replace the functions of a faulty or missing organ or other part of the human body The devices are human-made, whereas the living replacement parts can be obtained from the patient, a relative, a human cadaver, or a live animal or can be prospectively developed through genetic engineering. The concept that a disease state may be addressed not only by returning the malfunctioning organ to health using chemical agents or physical means but also by replacing the missing function with a natural or an artificial counterpart has brought about a revolution in therapeutics. I t is considerably more effective than drug therapy or corrective surgery in the treatment of many conditions, e.g., cardiac valve disease, heart block, malignant arrhythmia, arterial obstruction, cataract.

3. Defining Terms: Artificial organs: Human-made devices designed to replace, duplicate, or augment, functionally or cosmetically, a missing, diseased, or otherwise incompetent part of the body, either temporarily or permanently, and which require a nonbiologic material interface with living tissue. Assist device: An apparatus used to support or partially replace the function of a failing organ. Bioartificial organ: Device combining living elements (organelles, cells, or tissues) with synthetic materials in a therapeutic system. Biocompatibility: The ability of a material to perform with an appropriate host tissue response when incorporated for a specific application in a device, prosthesis, or implant. Biomaterial: Any material or substance (other than a drug) or combination of materials, synthetic or natural in origin, which can be used as a whole or as a part of a system which treats, augments, or replaces any tissue, organ, or function of the body.

4. A rtificial H eart and circulatory assist devices A rtificial heart : Device that replaces the heart and maintains blood circulation and oxygenation in the human body for varying periods of time. Typically used to bridge the time to heart transplantation, or to permanently replace the heart in the case that a heart transplant is impossible. Circulatory assist devices: Artificial devices that perform some or all of the functions of the heart. Vary significantly in design and indication but are typically used to provide either partial or full support for a heart that is unable to function adequately. Unlike a total artificial heart, the  CAD doesn't replace the heart . It just helps it do its job.  

5. THE FIRST ARTIFICIAL HEART O n Dec. 2, 1982, cardiothoracic surgeon  William DeVries, MD ,  carefully removed the ravaged heart of Dr. Barney Clark—a heart that tore like tissue paper due to years of treatment with steroids—and replaced it with the world’s first permanent artificial heart. Known as the Jarvik -7 , this aluminum and polyurethane device was connected to a 400-pound air compressor that would accompany Clark for the rest of his life - all 112 days of it. S econd recipient went on to live for 620 days. In the three subsequent recipients, one died from blood loss, and the other two lived for 10 and 14 months. Essentially, all patients died from different complications such as multi-organ failure, stroke, and infection to name a few. The main issue with the Jarvik 7 was that a “large pneumatic console” was required for treatment and therefore the patient could not leave the hospital. This caveat would not allow the Jarvik 7 to be a permanent artificial heart implant. Jarvik -7

6. The two main types of artificial hearts are the heart-lung machine and the mechanical heart . MECHANICAL HEART HEART LUNG MACHINE

7. Heart-lung machine P erforms the duties of both the heart , pushing blood through the body, and lungs , oxygenated the blood, to keep people alive while the surgeons work on their heart.  The   oxygenator   removes  carbon dioxide  and adds oxygen to the blood that is pumped into the  arterial system . The blood pumped back into the patient’s arteries is sufficient to maintain life at even the most distant parts of the body as well as in those organs with the greatest requirements (e.g., brain, kidneys, and liver). To do this, up to 5 litres (1.3 gallons) or more of blood must be pumped each minute. While the heart is relieved of its pumping duties, it can be stopped, and the surgeon can perform  open-heart surgery  that may include valve repair or replacement, repair of defects inside the heart, or revascularization of blocked arteries. A mechanical pump that maintains a patient’s blood circulation and oxygenation during  heart  surgery by diverting blood from the  venous system , directing it through tubing into an artificial  lung  (oxygenator), and returning it to the body.

8. FLOW IN OF VENOUS BLOOD OXYGENATED BLOOD COMES OUT OXYGENATOR

9. M echanical hearts: Mechanical hearts include: T otal artificial hearts: machines that are capable of replacing heart Ventricular assist devices  (VADs): assist the pumping action of the heart for prolonged periods without causing excessive damage to the blood components. Implantation of a total artificial heart requires removal of both of the patient’s ventricles (lower chambers). However, with the use of a VAD to support either the right or the left ventricle, the entire heart remains in the body. I mplanted only after maximal medical management has failed. U sed for cardiac resuscitation after cardiac arrest, for recovery from cardiogenic shock after heart surgery, and in some patients with  chronic   heart failure  who are waiting for a heart  transplant . Occasionally, mechanical hearts have been used as a permanent support in patients who do not qualify for a  heart transplant  or as a bridge to recovery of the patient’s own diseased heart. Some recipients of VADs have lived several years and have returned to work and normal physical activities.

10. T otal artificial hearts A total artificial heart ( TAH ) is a pump that is surgically installed to provide circulation and replace heart ventricles that are diseased or damaged. The ventricles pump blood out of the heart to the lungs and other parts of the body. Machines outside the body control the implanted pumps, helping blood flow to and from the heart. A TAH is recommended when the patient is having a heart failure caused by ventricles that no longer pump blood well enough, and need long-term support. TAH surgery may be an alternative treatment in certain patients who are unable to receive a heart transplant. As with any surgery, TAH surgery can lead to serious complications such as blood clots or infection.

11. Working of total artificial heart( TAH ): R eplaces the lower chambers of the heart, called  ventricles . Tubes connect the TAH to a power source that is outside the body. The TAH then pumps blood through the heart’s major artery to the lungs and the rest of the body. The TAH has 4 mechanical valves that work like the heart’s own valves to control blood flow. These valves connect the TAH to heart’s upper chambers, called the  atrium , and to the major arteries, the pulmonary artery , and the aorta. TAH duplicates the action of a normal heart, providing mechanical circulatory support and restoring normal blood flow through the body. The TAH is powered and controlled by a bedside console for patients in the hospital. After they leave the hospital, people with a TAH use a portable control device that fits in a shoulder bag or backpack and weighs about 14 pounds. It can be recharged at home or in a car.

12. Ventricular assist devices (VADs): A type of m echanical heart or circulatory assist devices  designed to assist one of the ventricles in pumping oxygenated blood through the aorta and to the body's tissues. The pump is placed inside the chest cavity, while the power source and system controller are carried on a harness outside the body. Although a  VAD  can be placed (implanted) in one or both ventricles of your heart, it is most frequently implanted in the left ventricle. When placed in the left ventricle, it's called a left ventricular assist device (LVAD). M ay be temporarily used while the patient wait for a donor heart to become available. K eep blood pumping throughout body despite a damaged heart. It will be removed when the patient receives new heart. Increasingly being used as a permanent treatment for people who have heart failure but who aren't good candidates for a heart transplant.

13. Working of Ventricular assist devices: A left VAD pumps oxygenated blood from the left ventricle to the aorta. Pneumatic  devices have membranes or sacs that are moved by air pressure to pump the blood, while electrical devices use electromechanical systems for power. Electrical devices are being developed that are totally implantable and do not require a tube exiting the skin; with these devices, power to the pump is transmitted between external and internal batteries through the intact skin.  There are 3 major components of the VAD: T he inflow cannula : a large tube that drains blood from the heart into the pump T he outflow cannula : returns blood to either the aorta (in a left ventricular assist device or LVAD) or pulmonary artery (in a right ventricular assist device). T he pump: is implanted in the left upper abdomen or left side of the chest. A driveline that contains the power wires exits the skin, usually on the right side of the abdomen, and connects to a controller that is worn on a belt. This controller is then connected to either a power-based unit that plugs into the wall or large batteries that can be worn in a holster or vest for portable use. The controller is the brain of the pump, and provides important information to the patient, caregivers, and medical team about VAD function and battery life

14. Approved medical devices SynCardia , Tucson, Arizona Aeson , Carmat ’s artificial heart AbioCor - AbioMed , Massachusetts

15. Engineering Design of Artificial Heart and Circulatory Assist Devices Define the Problem—Clarification of the Task: accomplished by writing the detailed design requirement or specification for the device; “to develop a device (perhaps totally implantable) that when implanted in the human will provide a longer and better quality of life than conventional pharmacologic or transplant therapy.” Fit of the System: first decide who the device is intended for(men, women, or children and also size); device must fit in these patients and cause minimal or no pathologic conditions; consider the volume and mass of the device, as well as any critical dimension such as the length, width, or height and the location of any tubes, conduits, or connectors. Pump Performance: must be specified in terms of cardiac output range; design specification include control of the device, specific requirements for synchronization of the device with the natural heart; For the total artificial heart, the device must always maintain balance between the left and right pumps; device must respond to the patient’s cardiac output requirements. Biocompatibility: should have a minimal effect on the immune system, should not promote infection, calcification, or tissue necrosis. Meeting these design requirements will require careful design of the pumping chamber and controller and careful selection of materials. Reliability: The reliability issue is very complex and involves moral, ethical, legal, and scientific issues. The design specification must deal with any service that the device may require. For instance, the overall design life of the device may be 5 years, but battery replacement at 2-year intervals may be allowed. Quality of Life: design specification must address the quality of life for the patient. The quality of life must thus be considered in relation to the patient’s quality of life without the device without ignoring the quality of life of individuals unaffected by cardiac disease

16. ADVANTAGES DISADVANTAGES Heart Surgeries would be performed easily Expensive No need to wait for Heart Donors Restricted Blood Flow Less Rejection and Blood Group Problems Chances of Failure  Reliable Limited Life

17. THANK YOU REFERENCES: Bronzino , J. D. (1999). Biomedical Engineering Handbook, Volume II (1st ed.). CRC Press. Total Artificial Heart | NHLBI, NIH . (n.d.). https:// www.nhlbi.nih.gov /health-topics/total-artificial-heart A rtificial heart . (n.d.). Encyclopedia Britannica. https:// www.britannica.com /science/artificial-heart Wikipedia contributors. (2022, March 13). Artificial heart . Wikipedia. https:// en.wikipedia.org /wiki/ Artificial_heart#Total_artificial_hearts