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KCl is not injected to stop the heart beating. The heart stops when the blood is flushed out of the coronary vessels and cooled. Preservation solution does contain high potassium levels amongst other electrolytes & glucose in order to preserve the heart
→Procedures: moving to talk. this is too unsourced to remain live
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Patients who are in need of a heart transplant but do not qualify, may be candidates for an [[artificial heart]] <ref name="Cook JA 2180"/> or a [[left ventricular assist device]] i.e. LVAD.
Patients who are in need of a heart transplant but do not qualify, may be candidates for an [[artificial heart]] <ref name="Cook JA 2180"/> or a [[left ventricular assist device]] i.e. LVAD.

==Procedures==
[[File:Orthotopic Heart Transplant.png|thumb|300px|Orthotopic [[heart transplant]]. Recipient P-waves (arrows).]]

===Pre-operative===
A typical heart transplantation begins when a suitable donor heart is identified. The heart comes from a recently [[deceased]] or [[Brain death|brain dead]] donor, also called a [[beating heart cadaver]]. The patient is contacted by a [[nurse]] coordinator and instructed to come to the hospital for evaluation and 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 suitable condition. Learning that a potential organ is unsuitable can induce distress in an already fragile patient, who usually requires emotional support before returning home.

The patient must also undergo emotional, psychological, and physical tests to verify mental health and ability to make good use of a new heart. The patient is also given [[immunosuppressant]] medication so that the patient's [[immune system]] does not [[Transplant rejection|reject]] the new heart.

===Operative===
[[Image:Heart transplant.jpg|thumb|right|300px|Schematic of a transplanted heart with native [[lung]]s and the [[great vessels]].]]
Once the donor heart passes inspection, the patient is taken into the [[operating room]] and given a [[general anaesthetic]]. Either an '''orthotopic''' or a '''heterotopic''' procedure follows, depending on the conditions of the patient and the donor heart.

====Orthotopic procedure====
The '''orthotopic procedure''' begins with a [[median sternotomy]], opening the chest and exposing the [[mediastinum]]. The [[pericardium]] is opened, the [[great vessels]] are [[dissect]]ed and the patient is attached to [[cardiopulmonary bypass]]. The donor's heart flushed with preservation solution before the heart is removed from the donor's body and packed in ice. Ice can usually keep the heart usable for four<ref>[http://www.drugs.com/pdr/custodiol-htk-solution.html Custodiol Htk Solution patient advice including side effects<!-- Bot generated title -->]</ref> to six hours depending on preservation and starting condition. The failing heart is removed by transecting the great vessels and a portion of the [[left atrium]]. The patient's [[pulmonary vein]]s 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 patient's remaining left atrium and the great vessels are [[surgical suture|suture]]d in place. The new heart is restarted<!--how?-->, the patient is weaned from cardiopulmonary bypass and the chest cavity is closed.

The orthotopic procedure was developed by Shumway and Lower at Stanford-Lane Hospital in [[San Francisco]] in 1958.<ref name="mcrae2007" />

====Heterotopic procedure====
In the '''heterotopic procedure''', the patient's own heart is not removed. 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 patient's original heart a chance to recover, and if the donor's heart fails (e.g., through [[transplant rejection|rejection]]), it can later be removed, leaving the patient's original heart. Heterotopic procedures are used only in cases where the donor heart is not strong enough to function by itself (because either the patient's body is considerably larger than the donor's, the donor's heart is itself weak, or the patient suffers from [[pulmonary hypertension]]).

===='Living organ' transplant====
In February 2006, at the [[Bad Oeynhausen]] Clinic for [[Thorax]] and Cardiovascular Surgery, [[Germany]], surgeons successfully transplanted a 'beating heart' into a patient.<ref>{{cite news | title=Bad Oeynhausen Clinic for Thorax- and Cardiovascular Surgery Announces First Successful Beating Human Heart Transplant | url=http://www.transmedics.com/wt/page/pr_1140714229 | date=23 February 2006 | publisher=TransMedics | accessdate = 2007-05-14}}</ref> Rather than cooling the heart, the living organ procedure keeps it at [[body temperature]] and connects it to a special machine called an [[Organ care system|Organ Care System]] that allows it to continue pumping warm, oxygenated blood. This technique can maintain the heart in a suitable condition for much longer than the traditional method.<!-- how much longer? -->

====Non-beating heart transplant====
The first successful non-beating heart transplant was achieved in Australia in 2014, performed by cardiothoracic surgeon [[Kumud Dhital]]. The transplant was made possible by the development of preservation technology able to preserve a heart, resuscitate it and to assess the function of the heart. The first patient to have this surgery was 57-year-old Michelle Gribilas.<ref>{{cite web|url=http://www.theguardian.com/science/2014/oct/24/dead-hearts-transplanted-into-living-patients|title= ‘Dead’ hearts transplanted into living patients in world first}}</ref> Papworth Hospital in England (where the first non-beating heart transplant in Europe was carried out) stated that the technique could increase the number of hearts available for transplant by at least 25%.<ref>{{cite web|url=http://www.bbc.co.uk/news/health-32056350|title=Europe's first non-beating heart transplant|website=BBC News|accessdate=16 April 2015}}</ref>

===Post-operative===
[[File:Пересаженное сердце в грудной клетке реципиента.JPG|thumb|right|Transplanted heart in the thorax of recipient]]
The patient is taken to the [[Intensive care unit|ICU]] to recover where they are started on immunosuppressants. When they are stable, they may move to a special recovery unit for [[Physical medicine and rehabilitation|rehabilitation]]. The duration of in-hospital, post-transplant care depends on the patient's general health, how well the heart is working, and the patient's ability to look after the new heart. Doctors typically prefer that patients leave the hospital 1–2 weeks after surgery, because of the risk of infection and presuming no complications. After release, the patient returns for regular check-ups and rehabilitation. They may also require emotional support. The frequency of hospital visits decreases as the patient adjusts to the transplant. The patient remains on [[immunosuppressant]] medication to avoid the possibility of [[transplant rejection|rejection]]. Since the [[vagus nerve]] is severed during the operation, the new heart beats at around 100 beats per minute unless [[nerve regrowth]] occurs.

The patient is regularly monitored to detect rejection. This surveillance can be performed via frequent [[biopsy]] or a gene expression blood test known as [[AlloMap Molecular Expression Testing]]. Typically, biopsy is performed immediately post-transplant and then AlloMap replaces it once the patient is stable. The transition from biopsy to AlloMap can occur as soon as 55 days after the transplant.


==Complications==
==Complications==

Revision as of 01:51, 17 November 2016

Heart transplantation
Diagram illustrating the placement of a donor heart in an orthotopic procedure. Notice how the back of the patient's left atrium and great vessels are left in place.
SpecialtyCardiology
ICD-9-CM37.51
MeSHD016027
MedlinePlus003003

A heart transplant, or a cardiac transplant, is a surgical transplant procedure performed on patients with end-stage heart failure or severe coronary artery disease when other medical or surgical treatments have failed. As of 2016, the most common procedure is to take a functioning heart (with or without transplantation of a lung or lungs; a cadaveric donor cardiectomy) from a recently deceased organ donor (the cadaveric allograft), and implant it into the patient. The patient's own heart is either removed (the cardiectomy for the recipient) and replaced with the donor heart (orthotopic procedure) or, less commonly, the recipient's diseased heart is left in place to support the donor heart (heterotopic procedure). Approximately 3500 heart transplants are performed every year in the world, more than half of which occur in the US.[1] Post-operation survival periods average 15 years.[2] Heart transplantation is not considered to be a cure for heart disease, but a life-saving treatment intended to improve the quality of life for recipients.[3]

History

One of the first mentions about the possibility of a heart transplantation was by American medical researcher Simon Flexner, who declared in a reading of his paper on “Tendencies in Pathology” in the University of Chicago in 1907 that it would be possible in the then-future for diseased human organs substitution for healthy ones by surgery — including arteries, stomach, kidneys and heart.[4]

Norman Shumway is widely regarded as the father of heart transplantation although the world's first adult human heart transplant was performed by a South African cardiac surgeon, Christiaan Barnard, utilizing the techniques developed and perfected by Shumway and Richard Lower.[5] Barnard performed the first transplant on Louis Washkansky on December 3, 1967, at the Groote Schuur Hospital in Cape Town, South Africa.[5][6] Adrian Kantrowitz performed the world's first pediatric heart transplant on December 6, 1967, at Maimonides Hospital in Brooklyn, New York, barely three days after Christiaan Barnard's pioneering operation (which used Shumway and Lower's procedure).[5] Norman Shumway performed the first adult heart transplant in the United States on January 6, 1968, at the Stanford University Hospital.[5]

Worldwide, about 3,500 heart transplants are performed annually. The vast majority of these are performed in the United States (2,000–2,300 annually).[1] Cedars-Sinai Medical Center in Los Angeles, California, currently is the largest heart transplant center in the world, having performed 132 adult transplants in 2015[7] alone. About 800,000 people have NYHA Class IV heart failure symptoms indicating advanced heart failure.[8] The great disparity between the number of patients needing transplants and the number of procedures being performed spurred research into the transplantation of non-human hearts into humans after 1993. Xenografts from other species and man-made artificial hearts are two less successful alternatives to allografts.[2]

Most published surgical methods of HT necessarily divide the Vagus nerve and thus amputate parasympathetic control of the myocardium.[citation needed]

Contraindications

Some patients are less suitable for a heart transplant, especially if they suffer from other circulatory conditions related to their heart condition. The following conditions in a patient increase the chances of complications;

Absolute contraindications:

Relative contraindications:

  • Insulin-dependent diabetes with severe organ dysfunction
  • Recent thromboembolism such as stroke
  • Severe obesity
  • Age over 65 years (some variation between centers) - older patients are usually evaluated on an individual basis.
  • Active substance abuse, such as alcohol, recreational drugs or tobacco smoking (which increases the chance of lung disease)

[9]

Patients who are in need of a heart transplant but do not qualify, may be candidates for an artificial heart [1] or a left ventricular assist device i.e. LVAD.

Complications

Post-operative complications include infection, sepsis, organ rejection, as well as the side-effects of the immunosuppressive medication. Since the transplanted heart originates from another organism, the recipient's immune system typically attempts to reject it. The risk of rejection never fully goes away, and the patient will be on immunosuppressive drugs for the rest of his or her life, but these may cause unwanted side effects, such as increased likelihood of infections or development of certain cancers. Recipients can acquire kidney disease from a heart transplant due to side effects of immunosuppressant medications. Many recent advances in reducing complications due to tissue rejection stem from mouse heart transplant procedures.[10] Surgery death rate is 5-10% in 2011.[11]

Prognosis

The prognosis for heart transplant patients following the orthotopic procedure has increased over the past 20 years, and as of June 5, 2009, the survival rates were:[12]

  • 1 year: 88.0% (males), 86.2% (females)
  • 3 years: 79.3% (males), 77.2% (females)
  • 5 years: 73.2% (males), 69.0% (females)

In a study spanning 1999 to 2007, 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, compared to men receiving male hearts, "men receiving female hearts had a 15% increase in the risk of adjusted cumulative mortality" over five years. No significant differences were noted with females receiving hearts from male or female donors.[13]

Famous recipients

Other notable recipients

At the time of his death on August 10, 2009, Tony Huesman was the world's longest living heart transplant recipient, having survived for 30 years, 11 months and 10 days, before dying of cancer.[16] Huesman received a heart in 1978 at the age of 20 after viral pneumonia severely weakened his heart.[17] The operation was performed at Stanford University under Dr. Norman Shumway.[18]

As of February 2016, the record holder for longest living heart recipient was Englishman John McCafferty. He received his heart on 20 October 1982.[16] He died aged 73 on 9 February 2016, 33 years after his operation. The operation was performed at Harefield Hospital in Middlesex under Sir Magdi Yacoub.[19]

Former Vice President of the United States Dick Cheney received a heart transplant on March 24, 2012[20] Because he was 71 years old at the time of the surgery, it sparked discussions about the upper age of transplant patients.[21]

See also

References

  1. ^ a b c Cook JA, Shah KB, Quader MA, et al. The total artificial heart. Journal of Thoracic Disease. 2015;7(12):2172-2180. doi:10.3978/j.issn.2072-1439.2015.10.70.
  2. ^ a b Till Lehmann (director) (2007). The Heart-Makers: The Future of Transplant Medicine (documentary film). Germany: LOOKS film and television.
  3. ^ Burch M.; Aurora P. (2004). "Current status of paediatric heart, lung, and heart-lung transplantation". Archives of Disease in Childhood. 89 (4): 386–389. doi:10.1136/adc.2002.017186. PMC 1719883. PMID 15033856.
  4. ^ MAY TRANSPLANT THE HUMAN HEART (.PDF), The New York Times, January 2, 1908.
  5. ^ a b c d McRae, D. (2007). Every Second Counts. Berkley.
  6. ^ "Memories of the Heart". Doylestown, Pennsylvania: Daily Intelligencer. November 29, 1987. p. A–18. {{cite news}}: Italic or bold markup not allowed in: |publisher= (help)
  7. ^ "SRTR -- Scientific Registry of Transplant Recipients". www.srtr.org. Retrieved 2016-10-24.
  8. ^ Reiner Körfer (interviewee) (2007). The Heart-Makers: The Future of Transplant Medicine (documentary film). Germany: LOOKS film and television.
  9. ^ Mehra MR, Canter CE, Hannan MM, Semigran MJ, Uber PA, et al. The 2016 International Society for Heart Lung Transplantation listing criteria for heart transplantation: A 10-year update. J Heart Lung Transplant. 2016 Jan. 35 (1):1-23.
  10. ^ Bishay R (2011). "The 'Mighty Mouse' Model in Experimental Cardiac Transplantation". Hypothesis. 9 (1): e5. doi:10.5779/hypothesis.v9i1.205.
  11. ^ Jung SH, Kim JJ, Choo SJ, Yun TJ, Chung CH, Lee JW (2011). "Long-term mortality in adult orthotopic heart transplant recipients". J. Korean Med. Sci. 26: 599–603. doi:10.3346/jkms.2011.26.5.599. PMC 3082109. PMID 21532848.
  12. ^ Heart Disease and Stroke Statistics--2012 Update The American Heart Association. Retrieved 27 November 2012.
  13. ^ Weiss, E. S.; Allen, J. G.; Patel, N. D.; Russell, S. D.; Baumgartner, W. A.; Shah, A. S.; Conte, J. V. (2009). "The Impact of Donor-Recipient Sex Matching on Survival After Orthotopic Heart Transplantation: Analysis of 18 000 Transplants in the Modern Era". Circulation: Heart Failure. 2 (5): 401–408. doi:10.1161/CIRCHEARTFAILURE.108.844183.
  14. ^ "A los 64 años, falleció Sandro". Infobae (in Spanish). 5 January 2010. {{cite news}}: Check |archiveurl= value (help)
  15. ^ Keeler, Scott (September 13, 2016). "Furman Hall of Famer Wyche in recovery after transplant". The Greenville News.
  16. ^ a b Prynne, Miranda (24 December 2013). "Brit sets new record for longest surviving heart transplant patient". The Daily Telegraph. United Kingdom. Retrieved 19 September 2014.
  17. ^ http://www.columbusdispatch.com/live/content/local_news/stories/2009/08/10/aheart.html?sid=101
  18. ^ Heart Transplant Patient OK After 28 Yrs (14 September 2006) CBS News. Retrieved 29 December 2006.
  19. ^ "Guinness World Record heart transplant patient dies". BBC News. BBC. Retrieved 11 February 2016.
  20. ^ "Cheney undergoes heart transplant surgery". Fox News. 24 March 2012.
  21. ^ OLIVIA KATRANDJIAN (March 25, 2012). "Is Dick Cheney Too Old for a Heart Transplant? -". ABC News. Retrieved 5 May 2015.
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