Tag Archives: Organ transplant

Vitamin B3 Identified as a Potential Antifungal Treatment

A team of scientists have identified vitamin B3 as a potential antifungal treatment. Infections by the yeast Candida albicans represent a significant public health problem and a common complication in immunodeficient individuals such as AIDS patients, cancer patients undergoing chemotherapy and recipients of organ transplants. While some treatments are available, their efficacy can be compromised by the emergence of drug-resistant strains.

The current study shows that a C. albicans enzyme, known as Hst3, is essential to the growth and survival of the yeast. Researchers found that genetic or pharmacological inhibition of Hst3 with nicotinamide, a form of vitamin B3, strongly reduced C. albicans virulence in a mouse model. Both normal and drug-resistant strains of C. albicans were susceptible to nicotinamide. In addition, nicotinamide prevented the growth of other pathogenic Candida species and Aspergillus fumigatus (another human pathogen), thus demonstrating the broad antifungal properties of nicotinamide.

“There is an urgent need to develop new therapies to kill C. albicans because it is one of the leading causes of hospital-acquired infections and is associated with high mortality rates,” explains study author Martine Raymond. “Although many issues remain to be investigated, the results of our study are very exciting and they constitute an important first step in the development of new therapeutic agents to treat fungal infections without major side effects for patients.”


Source
: Elements4Health

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Fountain of Youth from Chemicals of Easter Island Soil

A miraculous ‘elixir of youth’ which could extend the human life span by more than a decade is being developed by scientists.
………………
The anti-ageing pill was created from a chemical found in the soil of Easter Island –  one of the most remote and mysterious places on the planet.

In tests on animals, the chemical increased life expectancy by a staggering 38 per cent.

While the breakthrough sounds like something out of science fiction, scientists say the discovery is a major leap towards longer lives for everyone.

The drug, rapamycin, is already used to suppress the immune systems of organ transplant patients.

It is also employed in heart operations and is being tested for its anti-cancer properties.

The scientists believe that the drug could be developed within a decade.

Dr Arlan Richardson, who led the research at the University of Texas, said: ‘I never thought we would find an anti-ageing pill for people in my lifetime. However, rapamycin shows a great deal of promise to do just that.’

An anti-ageing pill is a Holy Grail for medical research and its development would have major repercussions for society.

In a world where people routinely live to 90 and 100, retirement ages would need to creep forward into the 70s while extended life spans would put enormous pressures on healthcare, housing and social services  –  as well as marriages.

The implications of a such a pill also depends on the quality of those extra years.

If an ageing drug delays every aspect of getting old, then users could enjoy 100 years of good health.

But if it simply postpones death, they could find their last few decades blighted by failing eyesight, hearing loss, frailty and dementia.
Rapamycin was discovered in the 1970s during a worldwide search for new antibiotics.

The chemical is produced by a microbe that lives in the Easter Island soil.
In its current form, the drug is too dangerous to hand out as an anti-ageing pill.

The compound suppresses the immune system and makes patients vulnerable to any viruses and bacteria.

The existing version of the drug also increases the risk of cancer and would need to be modified before using in human trials.

However, researchers believe the new discovery will lead them to similar  –  but less harmful  –  anti-therapies.

In the study, reported today in the journal Nature, scientists tested rapamycin on nearly 2,000 laboratory mice aged around 600 days  –  roughly the equivalent to a 60-year-old person.

Around a quarter of the mice were given a normal diet, the others the Easter Island chemical.
Land of mythical statues: Easter Island soil provided the anti-ageing chemical
The drug increased the maximum life span of the mice from 1,094 days to 1,245 days for females, and from 1,078 to 1,179 days for males.
From the point the mice began the treatment, the drug extended the females’ life expectancy by 38 per cent, and males by 28 per cent. Overall it expanded their life span by 9 to 14 per cent.

What amazed the scientists is that the drug worked even though the mice started to be given it only in middle and old age.

Until now, scientists have developed just two ways of extending the life span of mammals.

One is to tinker with their genes, the other to restrict their diet.

Repeated studies have shown that cutting calories can make animals and people live longer.

Experts believe that rapamycin  –  which acts on a protein in cells called TOR  –  might fool the body into thinking that calories are being restricted. British scientists described the findings as exciting  –  but stressed that rapamycin weakens the immune system, exposing patients to potentially dangerous diseases.

In its current form, an extended life span would come at the cost of having to live in a germ-free tent.

Researchers want to find another more subtle drug target that extends life, but which does not damage the immune system.

Dr Lynne Cox, researcher in ageing at Oxford University, said: ‘In no way should anyone consider using this particular drug to try to extend their own life span as rapamycin suppresses immunity. While the lab mice were protected from infection, that’s simply impossible in the human population.

‘What the study does is to highlight an important molecular pathway that new, more specific drugs might be designed to work on.

‘Whether it’s a sensible thing to try to increase life span this way is another matter: Perhaps increasing health span rather than overall life span might be a better goal.’

Source:Mail Online July 9. 2009

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Pancreas Transplant

Region of pancreas

Image via Wikipedia

Alternative Names:Transplant – pancreas

Introduction:
A pancreas transplant is surgery to implant a healthy pancreas(one that can produce insulin) from a donor into a patient who usually has diabetes. Pancreas transplants give the patient a chance to become independent of insulin injections.
Because the pancreas is a vital organ, performing functions necessary in the digestion process, the recipient’s native pancreas is left in place, and the donated pancreas is attached in a different location. In the event of rejection of the new pancreas which would quickly cause life-threatening diabetes, the recipient could not survive without the native pancreas still in place.

The healthy pancreas comes from a donor who has just died or who has suffered brain-death, but remains on life-support. The donor pancreas must meet numerous criteria to make sure it is suitable.it may be a partial pancreas from a living donor. Whole pancreas transplants from living donors are not possible, again because the pancreas is a necessary organ for digestion. At present, pancreas transplants are usually performed in persons with insulin-dependent diabetes, who have severe complications that are usually of a renal nature. Patients with pancreatic cancer are not eligible for valuable pancreatic transplantations, since the condition has a very high mortality rate and the disease, being highly .

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In addition to insulin, the pancreas produces other secretions, such as digestive enzymes, which drain through the pancreatic duct into the duodenum. Therefore, a portion of the duodenum is removed with the donor pancreas. The healthy pancreas is transported in a cooled solution that preserves the organ for up to 20 hours.

The patient’s diseased pancreas is not removed during the operation. The donor pancreas is usually inserted in the right lower portion of the patient’s abdomen and attachments are made to the patient’s blood vessels. The donor duodenum is attached to the patient’s intestine or bladder to drain pancreatic secretions.

The operation is usually done at the same time as a kidney transplant in diabetic patients with kidney disease.

Why the Procedure is Performed?
A pancreas transplant may be recommended for people with pancreatic disease, especially if they have type 1 diabetes and poor kidney function.

Pancreas transplant surgery is not recommended for patients who have:

*Heart or lung disease
*Other life-threatening diseases
*Solitary pancreas transplant for diabetes, without simultaneous kidney transplant, remains controversial.

History
The first pancreas transplantation was performed in 1966 by the team of Dr. Kelly, Dr. Lillehei, Dr.Merkel, Dr.Idezuki Y, & Dr. Goetz, three years after the first kidney transplantation. A pancreas along with kidney and duodenum was transplanted into a 28-year-old woman and her blood sugar levels decreased immediately after transplantation, but eventually she died three months later from pulmonary embolism. In 1979 the first living-related partial pancreas transplantation was done.

Types:-
There are three main types of pancreas transplantation:

*Simultaneous pancreas-kidney transplant (SPK), when the pancreas and kidney are transplanted simultaneously from the same deceased donor.

*Pancreas-after-kidney transplant (PAK), when a cadaveric, or deceased, donor pancreas transplant is performed after a previous, and different, living or deceased donor kidney transplant.

*Pancreas transplant alone, for the patient with type 1 diabetes who usually has severe, frequent hypoglycemia, but adequate kidney function.

Indications:-
In most cases, pancreas transplantation is performed on individuals with type 1 diabetes with end-stage renal disease The majority of pancreas transplantations (>90%) are simultaneous pancreas-kidney transplantions.

Preservation until implantation:-
The donor’s blood in the pancreatic tissue will be replaced by an ice-cold organ storage solution, such as UW (Viaspan) or HTK until the allograft pancreatic tissue is implanted.

Complications & Risk Factors:-
Complications immediately after surgery include rejection, thrombosis, pancreatitis and infection.

The risks for any anesthesia are:

*Heart attack
*Reactions to medications
*Problems breathing

The risks for any surgery are:
*Bleeding
*Infection
*Scar formation

The body’s immune system considers the transplanted organ foreign, and fights it accordingly. Thus, to prevent rejection, organ transplant patients must take drugs (such as cyclosporine and corticosteroids) that suppress the immune response of the body. The disadvantage of these drugs is that they weaken the body’s natural defense against various infections.

Prognosis:-
The prognosis after pancreas transplantation is very good. Over the recent years, long-term success has improved and risks have decreased. One year after transplantation more than 95% of all patients are still alive and 80-85% of all pancreases are still functional. After transplantation patients need lifelong immunosuppression. Immunosuppression increases the risk for a number of different kinds of infection and cancer.

The main problem, as with other transplants, is graft rejection. Immunosuppressive drugs, which weaken your body’s ability to fight infections, must be taken indefinitely. Normal activities can resume as soon as you are strong enough, and after consulting with the doctor. It is possible to have children after a transplant.

The major problems with all organ transplants are:

*Finding a donor
*Preventing rejection
*Long-term immunosuppression

Recovery:
It usually takes about 3 weeks to recover. Move your legs often to reduce the risk of blood clots or deep vein thrombosis. The sutures or clips are removed about two to three weeks after surgery. Resume normal activity as soon as possible, after consulting with the physician. A diet will be prescribed.

Resources:
http://en.wikipedia.org/wiki/Pancreas_transplantation
http://www.nlm.nih.gov/medlineplus/ency/article/003007.htm

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Lung Transplantation

Introduction:
Lung transplantation is a surgical procedure in which a patient’s diseased lungs are partially or totally replaced by lungs which come from a donor. While lung transplants carry certain associated risks, they can also extend life expectancy and enhance the quality of life for end-stage pulmonary patients.

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It is a life-preserving therapeutic intervention for a variety of end-stage pulmonary diseases that has been used successfully for the past 20 years. Since the early 1990s, more than 6400 lung transplants have been performed, and lung transplant programs exist in many countries.

The agency for health care policy and research in the United States has concluded that “lung transplantation has evolved as a clinical procedure achieving a favorable risk-benefit ratio and acceptable 1- and 2-year survival rates.”
.Qualifying conditions;-
Lung transplantation is the therapeutic measure of last resort for patients with end-stage lung disease who have exhausted all other available treatments without improvement. A variety of conditions may make such surgery necessary. As of 2005, the most common reasons for lung transplantation in the United States were:

*27% chronic obstructive pulmonary disease or COPD, including emphysema;

*16% idiopathic pulmonary fibrosis;

*14% cystic fibrosis;

*12% idiopathic (formerly known as “primary”) pulmonary hypertension;

* 5% alpha 1-antitrypsin deficiency;

*2% replacing previously transplanted lungs that have since failed;

*24% other causes, including bronchiectasis and sarcoidosis.

Contraindications:-
Despite the severity of a patient’s respiratory condition, certain preexisting conditions may make a person a poor candidate for lung transplantation. These conditions include:

*concurrent chronic illness (e.g. congestive heart failure, kidney disease, liver disease);

*current infections, including HIV and hepatitis;

*current or recent cancer;

*current use of alcohol, tobacco, or illegal drugs;

*age;

*psychiatric conditions;

*history of noncompliance with medical instructions.

History:-
The history of organ transplants began with several attempts that were unsuccessful due to transplant rejection. Animal experimentation by various pioneers, including Vladimir Demikhov and Dominique Metras, during the 1940s and 1950s, first demonstrated that the procedure was technically feasible. James Hardy of the University of Mississippi performed the first human lung transplant in 1963.  Following a left lung transplantation, the patient survived for 18 days. From 1963-1978, multiple attempts at lung transplantation failed because of rejection and problems with anastomotic bronchial healing. It was only after the invention of the heart-lung machine, coupled with the development of immunosuppressive drugs such as cyclosporine, that organs such as the lungs could be transplanted with a reasonable chance of patient recovery.

The first successful transplant surgery involving the lungs was a heart-lung transplant, performed by Dr. Bruce Reitz of Stanford University on a woman who had idiopathic pulmonary hypertension.

*1983: First successful single lung transplant (Tom Hall) by Joel Cooper (Toronto)

*1986: First successful double lung transplant (Ann Harrison) by Joel Cooper (Toronto)

*1988: First successful double lung transplant for cystic fibrosis by Joel Cooper (Toronto)

Transplant requirements:-

Requirements for potential donors:-
There are certain requirements for potential lung donors, due to the needs of the potential recipient. In the case of living donors, this is also in consideration of how the surgery will affect the donor.

*healthy;
*size match; the donated lung or lungs must be large enough to adequately oxygenate the patient, but small enough to fit within the recipient’s chest cavity;
*age;
*blood type.

Requirements for potential recipients:
While each transplant center is free to set its own criteria for transplant candidates, certain requirements are generally agreed upon:

*end-stage lung disease;

*has exhausted other available therapies without success;

*no other chronic medical conditions (e.g. heart, kidney, liver);

*no current infections or recent cancer. There are certain cases where preexisting infection is unavoidable, as with many patients with cystic fibrosis. In such cases, transplant centers, at their own discretion, may accept or reject patients with current infections of B. cepacia or MRSA.

*no HIV or hepatitis;

*no alcohol, smoking, or drug abuse;

*within an acceptable weight range (marked undernourishment or obesity are both associated
*with increased mortality);

*age (single vs. double tx);

*acceptable psychological profile;

*has social support system;

*financially able to pay for expenses;

*able to comply with post-transplant regimen. A lung transplant is a major operation, and following the transplant, the patient must be willing to adhere to a lifetime regimen of medications as well as continuing medical care.

Medical tests for potential transplant candidates:-
Patients who are being considered for placement on the organ transplant list must undergo an extensive series of medical tests in order to evaluate their overall health status and suitability for transplant surgery.

*blood typing; the blood type of the recipient must match that of the donor due to certain antigens that are present on donated lungs. A mismatch of blood type can lead to a strong response by the immune system and subsequent rejection of the transplanted organs;

*tissue typing; ideally, the lung tissue would also match as closely as possible between the donor and the recipient, but the desire to find a highly compatible donor organ must be balanced against the patient’s immediacy of need;

*Chest X-ray – PA & LAT, to verify the size of the lungs and the chest cavity;

*pulmonary function tests;

*CT Scan (High Resolution Thoracic & Abdominal);

*Bone mineral density scan;

*MUGA (Gated cardiac blood pool scan);

*Cardiac stress test (Dobutamine/Thallium scan);

*ventilation/perfusion (V/Q) scan;

*electrocardiogram;

*cardiac catheterization;

*echocardiogram.

Lung allocation score:-
Click to see:-> lung allocation score
Prior to 2005, donor lungs within the United States were allocated by the United Network for Organ Sharing on a first-come, first-serve basis to patients on the transplant list. This was replaced by the current system, in which prospective lung recipients of age of 12 and older are assigned a lung allocation score or LAS, which takes into account various measures of the patient’s health. The new system allocates donated lungs according to the immediacy of need rather than how long a patient has been on the transplant list. Patients who are under the age of 12 are still given priority based on how long they have been on the transplant waitlist. The length of time spent on the list is also the deciding factor when multiple patients have the same lung allocation score.

Patients who are accepted as good potential transplant candidates must carry a pager with them at all times in case a donor organ becomes available. These patients must also be prepared to move to their chosen transplant center at a moment’s notice. Such patients may be encouraged to limit their travel within a certain geographical region in order to facilitate rapid transport to a transplant center.

Types of lung transplant:-

Lobe
A lobe transplant is a surgery in which part of a living donor’s lung is removed and used to replace part of recipient’s diseased lung. This procedure usually involves the donation of lobes from two different people, thus replacing a single lung in the recipient. Donors who have been properly screened should be able to maintain a normal quality of life despite the reduction in lung volume.

Single-lung
Many patients can be helped by the transplantation of a single healthy lung. The donated lung typically comes from a donor who has been pronounced brain-dead.

Double-lung
Certain patients may require both lungs to be replaced. This is especially the case for people with cystic fibrosis, due to the bacterial colonisation commonly found within such patients’ lungs; if only one lung were transplanted, bacteria in the native lung could potentially infect the newly transplanted organ.

Heart-lung
Click to see:->Heart-lung transplant
Some respiratory patients may also have severe cardiac disease which in of itself would necessitate a heart transplant. These patients can be treated by a surgery in which both lungs and the heart are replaced by organs from a donor or donors.

A particularly involved example of this has been termed a “domino transplant” in the media. First performed in 1987, this type of transplant typically involves the transplantation of a heart and lungs into recipient A, whose own healthy heart is removed and transplanted into recipient B.

Procedure:-
While the precise details of surgery will depend on the exact type of transplant, there are many steps which are common to all of these procedures. Prior to operating on the recipient, the transplant surgeon inspects the donor lung(s) for signs of damage or disease. If the lung or lungs are approved, then the recipient is connected to an IV line and various monitoring equipment, including pulse oximetry. The patient will be given general anesthesia, and a machine will breathe for him or her.

It takes about one hour for the pre-operative preparation of the patient. A single lung transplant takes about four to eight hours, while a double lung transplant takes about six to twelve hours to complete. A history of prior chest surgery may complicate the procedure and require additional time.

Lobe:
Single-lung
In single-lung transplants, the lung with the worse pulmonary function is chosen for replacement. If both lungs function equally, then the right lung is usually favored for removal because it avoids having to maneuver around the heart, as would be required for excision of the left lung.

In a single-lung transplant the process starts out after the donor lung has been inspected and the decision to accept the donor lung for the patient has been made. An incision is generally made from under the shoulder blade around the chest, ending near the sternum. An alternate method involves an incision under the breastbone. In the case of a singular lung transplant the lung is collapsed, the blood vessels in the lung tied off, and the lung removed at the bronchial tube. The donor lung is placed, the blood vessels reattached, and the lung reinflated. To make sure the lung is satisfactory and to clear any remaining blood and mucus in the new lung a bronchoscopy will be performed. When the surgeons are satisfied with the performance of the lung the chest incision will be closed.

Double-lung
A double-lung transplant, also known as a bilateral transplant, can be executed either sequentially, en bloc, or simultaneously. Sequential is more common than en bloc.[2] This is effectively like having two separate single-lung transplants done. A less common alternative is the transplantation of both lungs en bloc or simultaneously.

….
Incision scarring from a double lung transplant.

.The transplantation process starts after the donor lungs are inspected and the decision to transplant has been made. An incision is then made from under the patient’s armpit, around to the sternum, and then back towards the other armpit, this is known as a clamshell incision. In the case of a sequential transplant the recipients lung with the poorest lung functions is collapsed, the blood vessels tied off, and cut at the corresponding bronchi. The new lung is then placed and the blood vessels reattached. To make sure the lung is satisfactory before transplanting the other a bronchoscopy is performed. When the surgeons are satisfied with the performance of the new lung, surgery on the second lung will proceed. In 10% to 20% of double-lung transplants the patient is hooked up to a heart-lung machine which pumps blood for the body and supplies fresh oxygen.

Post-operative care:-
Immediately following the surgery, the patient is placed in an intensive care unit for monitoring, normally for a period of a few days. The patient is put on a ventilator to assist breathing. Nutritional needs are generally met via total parenteral nutrition, although in some cases a nasogastric tube is sufficient for feeding. Chest tubes are put in so that excess fluids may be removed. Because the patient is confined to bed, a urinary catheter is used. IV lines are used in the neck and arm for monitoring and giving medications. After a few days, barring any complications, the patient may be transferred to a general inpatient ward for further recovery. The average hospital stay following a lung transplant is generally one to three weeks, though complications may require a longer period of time.

There may be a number of side effects following the surgery. Because certain nerve connections to the lungs are cut during the procedure, transplant recipients cannot feel the urge to cough or feel when their new lungs are becoming congested. They must therefore make conscious efforts to take deep breaths and cough in order to clear secretions from the lungs. Their heart rate responds less quickly to exertion due to the cutting of the vagus nerve that would normally help regulate it. They may also notice a change in their voice due to potential damage to the nerves that coordinate the vocal cords.

Risks Factors:-
As with any surgical procedure, there are risks of bleeding and infection. The newly transplanted lung itself may fail to properly heal and function. Because a large portion of the patient’s body has been exposed to the outside air, sepsis is a possibility, so antibiotics will be given to try to prevent that.

Transplant rejection is a primary concern, both immediately after the surgery and continuing throughout the patient’s life. Because the transplanted lung or lungs come from another person, the recipient’s immune system will “see” it as an invader and attempt to neutralize it. Transplant rejection is a serious condition and must be treated as soon as possible.

Signs of rejection:

*fever;

*flu-like symptoms, including chills, dizziness, nausea, general feeling of illness;

*increased difficulty in breathing;

*worsening pulmonary test results;

*increased chest pain or tenderness.

In order to prevent transplant rejection and subsequent damage to the new lung or lungs, patients must take a regimen of immunosuppressive drugs. Patients will normally have to take a combination of these medicines in order to combat the risk of rejection. This is a lifelong commitment, and must be strictly adhered to. The immunosuppressive regimen is begun just before or after surgery. Usually the regimen includes cyclosporine, azathioprine and corticosteroids, but as episodes of rejection may reoccur throughout a patient’s life, the exact choices and dosages of immunosuppressants may have to be modified over time. Sometimes tacrolimus is given instead of cyclosporine and mycophenolate mofetil instead of azathioprine.

The immunosuppressants that are needed to prevent organ rejection also introduce some risks. By lowering the body’s ability to mount an immune reaction, these medicines also increase the chances of infection. Antibiotics may be prescribed in order to treat or prevent such infections. Certain medications may also have nephrotoxic or other potentially harmful side-effects. Other medications may also be prescribed in order to help alleviate these side effects. There is also the risk that a patient may have an allergic reaction to the medications. Close follow-up care is required in order to balance the benefits of these drugs versus their potential risks.

Chronic rejection, meaning repeated bouts of rejection symptoms beyond the first year after the transplant surgery, occurs in approximately 50% of patients. Such chronic rejection presents itself as bronchiolitis obliterans, or less frequently, atherosclerosis.

Prognosis:-
These statistics are based on data from 2006. The source data made no distinction between living and deceased donor organs, nor was any distinction made between lobar, single, and double lung transplants.

Lung transplant-1 year survival- 84.9%, 5 years survival- 51.6%,10 years survival – 25.6%

Heart-lung transplant-1 year survival 77.8%,5 years survival- 43.6%,10 years survival -27.3%

Transplanted lungs typically last three to five years before showing signs of failure.

Living donor tranplantation:-
Living lobar lung transplantation was developed as a procedure for adult and pediatric patients considered too ill to await cadaveric transplantation. Despite fairly extensive experience, no donor mortality has been reported, and morbidity has been relatively low. Compared to bilateral cadaveric lung transplants, long-term studies have shown that the relatively smaller-sized lobes can provide similar pulmonary function and exercise capacity. Living lobar lung transplantation should be considered in a patient with a clinically deteriorating condition. Although no deaths have been reported in the donor cohort, a risk of death between 0.5% and 1% should be quoted, pending further data. A case series of 128 living lobar lung transplantations performed in 123 patients between 1993 and 2003 was published. The actuarial survival among the living lobar recipients was 70%, 54%, and 45%, at 1, 3, and 5 years, respectively.

Resources:
http://en.wikipedia.org/wiki/Lung_transplantation
http://emedicine.medscape.com/article/429499-followup

Heart Transplantation

Introduction:
A heart transplant is an operation in which a failing, diseased heart is replaced with a healthier, donor heart. Heart transplant is a treatment that’s usually reserved for people who have tried medications or other surgeries, but their conditions haven’t improved sufficiently.

While a heart transplant is a major operation, medical technology has improved greatly since the first heart transplant in 1967, and your chance of survival is higher than ever.

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When faced with a decision about having a heart transplant, know what to expect of the heart transplant process, the surgery itself, potential risks and follow-up care.

The most common procedure is to take a working heart from a recently deceased organ donor (allograft) and implant it into the patient. The patient’s own heart may either be removed (orthotopic procedure) or, less commonly, left in to support the donor heart (heterotopic procedure). It is also possible to take a heart from another species (xenograft), or implant a man-made artificial one, although the outcome of these two procedures has been less successful in comparison to the far more commonly performed allografts.

Cardiac transplantation is a widely accepted therapy for the treatment of end-stage congestive heart failure. Most candidates for cardiac transplantation have not been helped by conventional medical therapy and are excluded from other surgical options because of the poor condition of the heart. About 45% of the candidates have ischemic cardiomyopathy; however, this percentage is rising because of the increase in coronary artery disease in younger age groups. Of the candidates, 54% have some form of dilated cardiomyopathy, which often has an unclear origin. The remaining 1% of candidates fall into the category of other diseases, including congenital heart disease, that are not amenable to surgical correction.

Candidacy determination and evaluation are key components of the process, as is postoperative follow-up care and immunosuppression management. Proper execution of these steps can culminate in an extremely satisfying outcome for both the physician and patient.

Why it’s done:-
Heart transplants are performed when other treatments for heart problems haven’t worked, leading to heart failure. In adults, heart failure can be caused by:

*Coronary artery disease
*Cardiomyopathy
*Valvular heart disease
*Congenital heart defect — a heart problem you’re born with
*Failure of a previous heart transplant

In children, heart failure is most often caused by a congenital heart defect.

A heart transplant isn’t the right treatment for everyone, however. Certain factors may mean you’re not a good candidate for a heart transplant. While each case is considered individually by a transplant center, factors that could prevent you from having a heart transplant include:

*Being age 65 or older
*Having another medical condition that could shorten life, regardless of receiving a donor heart
*Poor blood circulation
*Personal medical history of cancer
*Being unwilling or unable to make lifestyle changes necessary to keep your donor heart healthy

Specific indications:-

*Dilated cardiomyopathy
*Ischemic cardiomyopathy
*Congenital heart disease for which no conventional therapy exists or that conventional therapy has failed
*Ejection fraction less than 25%
*Intractable angina or malignant cardiac arrhythmias for which conventional therapy has been exhausted
*Pulmonary vascular resistance of less than 2 Wood units
*Age younger than 65 years

Ability to comply with medical follow-up care.

History
The first heart transplanted into a human occurred in 1964 at the University of Mississippi Medical Center in Jackson, Mississippi when a team led by Dr. James Hardy transplanted a chimpanzee heart into a dying patient. The heart beat for 70 minutes before stopping. Dr. Hardy had performed the first human lung transplant the previous year. [1] The first human to human heart transplant was performed by cardiac surgeon Christiaan Barnard at Groote Schuur Hospital in December 1967. The patient was Louis Washkansky of Cape Town, South Africa, who lived for 18 days after the procedure before dying of pneumonia. The donor was Denise Darvall, who was rendered brain dead in a car accident.

The first successful United States heart transplant was done at Stanford University by doctor Norman Shumway in January, 1968. Subsequently, another transplant was done at St. Lukes hospital in Houston Texas by Denton Cooley in June 1968. The donor was a teenage suicide victim (who had had an aortic coarctation repaired as a young child, also by Dr. Cooley) and the recipient, Mr. Thomas, had terminal severe cardiomyopathy. He survived 8 months before dying of rejection of the transplanted heart. A series of five subsequent heart transplants were done that month by Dr. Cooley followed by a number of transplants in Houston that year before the program was canceled, leaving only Norman Shumway at Stanford University doing heart transplants and research on the rejection phenomenon.

On 27 April 1968, French surgeon Christian Cabrol performed the first European heart transplantation in the Paris Pitié-Salpêtrière Hospital. The patient was a 66 year old man, Clovis Roblain, who survived 53 hours before dying of a pulmonary embolism.

In 1984, at two years old, Elizabeth Craze became the youngest surviving heart transplant patient.

The concept of heart transplantation dates back to at least 400 AD in China. The book of Liezi tells a story of Bian Que exchanging the hearts of two warriors to balance their personal characteristics.

Risk Factors:

Although receiving a donor heart can save your life, having a heart transplant has many risks. The most significant risk is your body rejecting the donor heart.

Rejection of the donor heart
Your immune system may see your donor heart as a foreign object that’s not supposed to be in your body. If this happens, your immune system will try to attack your donor heart. Although all people who receive a heart transplant receive immunosuppressants — medications that suppress the activity of your immune system — nearly 25 percent of heart transplant recipients still have some signs of rejection during the first year after transplantation.

To determine whether your body is rejecting the new heart, you’ll have frequent biopsy tests for several months after your transplant. During the biopsy, a tube is inserted into a vein in your neck or groin and directed to your heart. A biopsy device is run through the tube to extract a tiny sample of heart tissue, which is examined in a lab. Because rejection is most likely to occur in the early weeks and months after heart transplantation, the frequency of heart biopsies is greatest during this early period. It’s possible you’d have signs or symptoms that your body is rejecting your donor heart. These signs and symptoms could include:

*Shortness of breath
*Fever
*Weight gain due to water retention
*Not urinating as much as usual
*Fatigue

Additional risks :-
Other risks following your heart transplant include:

*Problems with your arteries. After your transplant, it’s possible the walls of the arteries in your heart could thicken and harden, leading to cardiac allograft vasculopathy (CAV). This can make blood circulation through your heart difficult and can cause a heart attack, heart failure, heart arrhythmias or sudden cardiac death.

*Medication side effects. The immunosuppressants you’ll need to take for the rest of your life can cause serious kidney damage and other problems.

*Cancer. Immunosuppressants can also increase your cancer risk. Taking these medications can put you at a greater risk of skin and lip tumors and non-Hodgkin’s lymphoma, among others.

*Infection. Immunosuppressants decrease your body’s ability to fight infection. Many people who have heart transplants have an infection that requires them to be admitted to the hospital the first year after their transplant.

Procedures:-

Pre-operative
A typical heart transplantation begins with a suitable donor heart being located from a recently deceased or brain dead donor. The transplant patient is contacted by a nurse coordinator and instructed to attend the hospital in order to be evaluated for the operation and given pre-surgical medication. At the same time, the heart is removed from the donor and inspected by a team of surgeons to see if it is in a suitable condition to be transplanted. Occasionally it will be deemed unsuitable. This can often be a very distressing experience for an already emotionally unstable patient, and they will usually require emotional support before being sent home. The patient must also undergo many emotional, psychological, and physical tests to make sure that they are in good mental health and will make good use of their new heart. The patient is also given immunosuppressant medication so that their immune system will not reject the new heart.

Operative
Once the donor heart has passed its inspection, the patient is taken into the operating room and given a general anesthetic. Either an orthotopic or a heterotopic procedure is followed, depending on the condition of the patient and the donor heart.

Orthotopic procedure
The orthotopic procedure begins with the surgeons performing a median sternotomy to expose the mediastinum. The pericardium is opened, the great vessels are dissected and the patient is attached to cardiopulmonary bypass. The failing heart is removed by transecting the great vessels and a portion of the left atrium. The pulmonary veins are not transected; rather a circular portion of the left atrium containing the pulmonary veins is left in place. The donor heart is trimmed to fit onto the patients remaining left atrium and the great vessels are sutured in place. The new heart is restarted, the patient is weaned from cardiopulmonary bypass and the chest cavity is closed.

Heterotopic procedure
In the heterotopic procedure, the patient’s own heart is not removed before implanting the donor heart. The new heart is positioned so that the chambers and blood vessels of both hearts can be connected to form what is effectively a ‘double heart’. The procedure can give the patients original heart a chance to recover, and if the donor’s heart happens to fail (eg. through rejection), it may be removed, allowing the patients original heart to start working again. Heterotopic procedures are only used in cases where the donor heart is not strong enough to function by itself (due to either the patients body being considerably larger than the donor’s, the donor having a weak heart, or the patient suffering from pulmonary hypertension).

Post-operative
The patient is taken into ICU to recover. When they wake up, they will be transferred to a special recovery unit in order to be rehabilitated. How long they remain in hospital post-transplant depends on the patient’s general health, how well the new heart is working, and their ability to look after their new heart. Doctors typically like the new recipients to leave hospitals soon after surgery because of the risk of infection in a hospital (typically 1 – 2 weeks without any complications). Once the patient is released, they will have to return to the hospital for regular check-ups and rehabilitation sessions. They may also require emotional support. The number of visits to the hospital will decrease over time, as the patient adjusts to their transplant. The patient will have to remain on lifetime immunosuppressant medication to avoid the possibility of rejection. Since the vagus nerve is severed during the operation, the new heart will beat at around 100 bpm until nerve regrowth occurs.

Living organ’ transplant
Doctors made medical history in February 2006, at Bad Oeynhausen Clinic for Thorax- and Cardiovascular Surgery, Germany, when they successfully transplanted a ‘beating heart’ into a patient.Normally a donor’s heart is injected with potassium chloride in order to stop it beating, before being removed from the donor’s body and packed in ice in order to preserve it. The ice can usually keep the heart fresh for a maximum of four to six hours with proper preservation, depending on its starting condition. Rather than cooling the heart, this new procedure involves keeping it at body temperature and hooking it up to a special machine called an Organ Care System that allows it to continue beating with warm, oxygenated blood flowing through it. This can maintain the heart in a suitable condition for much longer than the traditional method.

Prognosis:-

The prognosis for heart transplant patients following the orthotopic procedure has greatly increased over the past 20 years, and as of 11 August 2006, the survival rates were as follows.[8]

*1 year: 86.1% (males), 83.9% (females)
*3 years: 78.3% (males), 74.9% (females)
*5 years: 71.2% (males), 66.9% (females)

In a November 2008 study conducted on behalf of the U.S. federal government by Dr. Eric Weiss of the Johns Hopkins University School of Medicine, it was discovered that heart transplants- all other factors being accounted for- work better in same-sex transplants (male to male, female to female). However, due to the present acute shortage in donor hearts, this may not always be feasible.

As of the end of 2007, Tony Huesman is the world’s longest living heart transplant patient, having survived for 29 years with a transplanted heart. Huesman received a heart in 1978 at the age of 20 after viral pneumonia severely weakened his heart. The operation was performed at Stanford University under American heart transplant pioneer Dr. Norman Shumway, who continued to perform the operation in the U.S. after others abandoned it due to poor results.. Another noted heart transplant recipient, Kelly Perkins, climbs mountains around the world to promote positive awareness of organ donation. Perkins is the first heart transplant recipient to climb to the peaks of Mt. Fuji, Mt. Kilimanjaro, the Matterhorn, Mt. Whitney, and Cajon de Arenales in Argentina in 2007, 12 years after her transplant surgery. Dwight Kroening is yet another noted recipient promoting positive awareness for organ donation. Twenty two years after his heart transplant, he is the first to finish an Ironman competition.  Fiona Coote was the second Australian to receive a heart transplant in 1984 (at age 14) and the youngest Australian. At 24 years since her transplant she is also a long term survivor and is involved in publicity and charity work for the red cross, and promoting organ donation in Australia.

The record for heart transplant longevity in a senior recipient may go to Edward Daunheimer of Newburyport, Massachusetts, who received his heart on 19 February 1997 at the Tufts New England Medical Center at the age of 65 (the upper age limit for heart transplants). Mr. Daunheimer has so far lived a healthy life for 12 years with his new heart, defying statistical probabilities by a large margin.

Expected results:-
Most people who receive a heart transplant enjoy a high quality of life. They can return to work within three to six months of a heart transplant and have few activity restrictions.

Recipient survival rates vary based on a number of factors, but overall the survival rate is nearly 90 percent after one year and 72 percent after five years.

What if your new heart fails?
Heart transplants aren’t successful for everyone. Your new heart may fail because of organ rejection or because of the development of valvular heart disease or coronary artery disease. Should this happen, your doctor may recommend adjusting your medications or in more extreme cases, another heart transplant.

In some cases, additional treatment options are limited and you may choose to discontinue treatment. Discussions with your heart transplant team, physician and family should address your expectations and preferences for treatment, emergency care and end-of-life care.

Resources:-
http://emedicine.medscape.com/article/429816-overview
http://en.wikipedia.org/wiki/Heart_transplantation
http://www.mayoclinic.com/health/heart-transplant/

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