Jatene procedure
Encyclopedia
The Jatene procedure, or arterial switch, is an open heart
surgical procedure used to correct dextro-transposition of the great arteries
(d-TGA); its development was pioneered by Canadian cardiac
surgeon William Mustard
and it was named for Brazil
ian cardiac surgeon Adib Jatene, who was the first to use it successfully. It was the first method of d-TGA repair to be attempted, but the last to be put into regular use because of technological
limitations at the time of its concept
ion. Use of the arterial switch is historically preceded by two atrial switch methods: the Senning
and Mustard procedure
s.
This surgery may be used in combination with other procedures for treatment of certain cases of double outlet right ventricle
(DORV) in which the great arteries
are dextro-transposed.
adjusts to the lower pulmonary pressure
and is therefore unable to support the systemic circulation
. In the event of sepsis
or delayed diagnosis
, a combination of pulmonary artery banding
(PAB) and shunt
construction may be used to increase the left ventricular mass sufficiently to make an arterial switch possible later in infancy
.
. Under preferable conditions, the intra-operative and post-operative success rate is 96% or more, with a comparable survival rate after 5 years. Approximately 10% of arterial switch recipients develop residual pulmonary stenosis
post-operatively, which can lead to right heart
failure if left untreated; treatment usually involves endovascular stenting and/or xenograft patching.
type is known, a family member with a compatible blood type
may donate
some or all of the blood needed for transfusion
during the use of a heart-lung machine
(HLM). The patient's mother
is normally unable to donate blood for the transfusion, as she will not be able to donate blood during pregnancy
(due to the needs of the fetus
) or for a few weeks after giving birth
(due to blood loss), and the process of collecting a sufficient amount of blood may take several weeks to a few months. However, in cases where the individual has been diagnosed but surgery must be delayed, maternal (or even autologous, in certain cases) blood donation may be possible, as long as the mother has a compatible blood type. In most cases, though, the patient receives a donation from a blood bank
. A blood transfusion is necessary for the arterial switch because the HLM needs its "circulation" filled with blood and an infant does not have enough blood on their own to do this (in most cases, an adult would not require blood transfusion).
The patient will require a number of imaging
procedures in order to determine the individual anatomy
of the great arteries and, most importantly, the coronary arteries. These may include angiography, magnetic resonance imaging
(MRI), and/or computed tomography
(CT scan). The coronary arteries are carefully mapped out in order to avoid unexpected intra-operative complications in transferring them from the native aorta to the neo-aorta.
on vomit while unconscious.
After the patient is anesthetized, they receive the following drugs
via intravenous drip, which continue as necessary throughout the procedure:
, and the patient is given heparin
to prevent the blood from clotting. A generous section of pericardium
is harvested, then disinfected and sterilized
with a weak solution of glutaraldehyde
; and the coronary and great artery anatomy are examined. The ductus arteriosus
and right pulmonary branch, up to and including the first branches in the hilum
of the right lung
, are separated from the surrounding supportive tissue
to allow mobility of the vessels
. Silk
marking sutures may be placed in the pulmonary trunk at this time, to indicate the commissure of the aorta to the neo-aorta; alternatively, this may be done later in the procedure.
The cardiopulmonary bypass is then initiated by inserting a cannula
into the ascending aorta
as distally from the aortic root as possible while still supplying all arterial
branches, another cannula is inserted into the right atrium
, and a vent is created for the left ventricle
via catheterization of the right superior pulmonary vein. The HLM is started at a low-flow
and the patient's body
is cooled to a rectal temperature
of 20 °
C
(68 °F
), which prevents the brain damage
otherwise associated with the temporary circulatory arrest
necessary during the procedure; the patient must be cooled for a minimum of 20 minutes prior to beginning the repair.
While the patient is cooling, the ductus arteriosus is ligated
at both the aortic and pulmonary ostia, then transected at its center; the left pulmonary branch, including the first branches in the hilum of the left lung, is separated from the supportive tissue; and the aorta is marked at the site it will be transected, which is just below the pulmonary bifurcation, proximal to where the pulmonary artery will be transected.
When the patient is fully cooled, the ascending aorta is clamped as close as possible below the HLM cannula, and cryocardioplegia is achieved by delivering cold blood to the heart via the ascending aorta (below the cross clamp). The aorta is then transected at the marked spot, and the pulmonary artery is transected a few millimetres below the bifurcation. The vessels are again examined, and the pulmonary root is inspected for left ventricular outflow tract obstruction (LVOTO). If a ventricular septal defect
(VSD) is present, it may be repaired, at this point via either the aortic
or pulmonary valve
; it may alternatively be repaired later in the procedure.
The great arteries are usually arranged using the Lecompte maneuver, with the aortic cross clamp positioned to hold the pulmonary artery anterior to the ascending aorta; though with some congenital arrangements of the great arteries, such as side-by-side, this is not possible and the arteries will be transplanted in the non-anatomic 'anterior aorta' arrangement. If the aortic commissure has not yet been marked, it may be done at this point, using the same method as would be used prior to bypass; however, there is a third opportunity for this still later in the procedure.
Coronary arteries are examined closely, and the ostia and proximal arterial course are identified, as are any infundibular branches, if they exist. The coronary ostia and a large "button" of surrounding aortic wall are then excised from the aorta, well into the sinus of Valsalva; and the proximal sections of the coronary arteries are separated from the surface of the heart, which prevents tension
or distortion
after anastomosis
to the neo-aorta. Infundibular branches are sometimes unable to be spared, but this is a very rare occurrence. If the aortic commissure has not previously been marked, the excised coronary arteries will be used to determine the implant
ation position of the aorta.
The aorta is then transplanted onto the pulmonary root, using either absorbable or permanent continuous suture. The aortic clamp is temporarily removed while small sections of the neo-aorta are cut away to accommodate the coronary ostia, and a continuous absorbable suture is then used to anastomose each coronary "button" into the prepared space. In most cases, the coronary implantation sites will be at left and right anterior positions at the base of the neo-aorta; however, if the circumflex coronary artery branches from the right coronary artery
, the circumflex coronary artery will be distorted if the pair are not implanted higher than normal on the neo-aorta, and in some cases they may need to be implanted above the aortic commissure, on the native aorta itself. The circumflex coronary artery may originate from the same coronary sinus as, rather than directly from, the right coronary artery, in which case they may still be excised on the same "button" and transplanted similarly to if they had a shared ostium, unless one or both have intramural communication with another coronary vessel. Sometimes, one or more coronary ostia are located very close to the valvular
opening and a small portion of the native aortic valve must be removed when the coronary artery is excised, which causes a generally mild, and usually well-tolerated
, neo-pulmonary valve regurgitation
.
The HLM is turned off and the aortic and atrial cannula are removed, then an incision is made in the right atrium, through which the congenital or palliative atrial septal defect
(ASD) is repaired; where a Rashkind balloon atrial septostomy
was used, the ASD should be able to be closed with sutures, but cases involving large congenital ASDs or Blalock-Hanlon atrial septectomy, a pericardial, xenograft, or Dacron patch may be necessary. If there is a VSD which has not yet been repaired, this is performed via the atrial incision and tricuspid valve
, using sutures for a small defect or a patch for a large defect.
When the septal defects have been repaired and the atrial incision is closed, the previously removed cannula are replaced and the HLM is restarted. The left ventricle is then vented and the cross clamp removed from the aorta, enabling full-flow to be re-established and rewarming to begin; at this point the patient will receive an additional dose of Regatine to keep blood pressure
under control. The previously harvested pericardium is then used to patch the coronary explantation sites, and to extend - and widen, if necessary - the neo-pulmonary root, which allows the pulmonary artery to be anastamosed without residual tension; the pulmonary artery is then transplanted to the neo-pulmonary root.
s, temporary pacemaker
leads, and ventilated before weaning from the HLM is begun; and administration of post-operative drugs is initiated, these include:
The rib cage
is relaxed and the external surgical wound
is bandaged, but the sternum and chest incision are left open to provide extra room in the pleural cavity
, allowing the heart room to swell and preventing pressure caused by pleural effusion
.
can then be gradually introduced via nasogastric tube (NG tube); the primary goal after a successful arterial switch, and before hospital
discharge, is for the infant
to gain back the weight they have lost and continue to gain weight at a normal or near-normal rate.
pathologist Matthew Baillie
first described TGA in 1797, presumably as a posthumous diagnosis. Early mortality rates
at this time are estimated to have been as high as 90%; the survivors would have been those with one or more concomitant intracardiac shunts
(ASD, patent ductus arteriosus
(PDA), patent foramen ovale (PFO), and/or VSD), and are unlikely to have survived past adolescence
.
In 1950, American
surgeons Alfred Blalock
and C. Rollins Hanlon introduced the Blalock-Hanlon atrial septectomy, which was then routinely used to palliate patients. This would have effectively reduced early mortality rates, particularly in cases with no concomitant shunts, but is unlikely to have reduced late mortality rates.
Mustard first conceived of, and attempted, the anatomical repair (arterial switch) for d-TGA in the early 1950s. His few attempts were unsuccessful due to technical difficulties posed by the translocation of the coronary arteries, and the idea was abandoned.
Swedish cardiac surgeon Åke Senning
described the first corrective surgery for d-TGA (the Senning procedure) in 1959, which involved using the atrial septum to create an intratrial baffle
that redirected bloodflow
at the atrial
level; Senning yielded a high success rate using this procedure, significantly lowering both early and late mortality rates.
Due to the technical complexity of the Senning procedure, others could not duplicate his success rate; in response, Mustard developed a simpler alternative method (the Mustard procedure) in 1964, which involved constructing a baffle from autologous pericardium
or synthetic
material, such as Dacron. This procedure yielded early and late mortality rates comparable to the Senning procedure; however, a late morbidity rate was eventually discovered in relation to the use of synthetic graft material, which does not grow with the recipient and eventually causes obstruction.
In 1966, American surgeons William Rashkind and William Miller transformed the palliation of d-TGA patients with the innovative Rashkind balloon atrial septostomy, which, unlike the thoracotomy
required by a septectomy, is performed through the minimally invasive surgical technique of cardiac catheterization
.
Although the atrial switch procedures dramatically reduced both early and late mortality rates, these statistics remained high, partly due to the wait time required between birth
and surgery (pre-operative mortality: 5-10%; early mortality: 0-15%; late mortality: 20-25%). A concomitant VSD raises the early mortality rate for atrial switch to 10-60%, even in cases where the VSD is repaired. The late morbidity rate is also very high in atrial switch recipients, with 13-100% developing post-operative complications related to intra-operative damage caused to the sinus node and/or the inherent unsuitability of the heart chamber
s for role reversal.
These statistics, combined with advances in microvascular surgery, created a renewed interest in Mustard's original concept of an arterial switch procedure. The first successful arterial switch was performed on a forty-two day old d-TGA + VSD infant by Jatene in 1975. Egypt
ian cardiac surgeon Magdi Yacoub
was subsequently successful in treating TGA with intact septum when preceded by pulmonary artery banding and systemic-to-pulmonary shunt palliation. Austria
n surgeon B. Eber was the first to recount a small series of successful arterial switch procedures, and the first large successful series was reported by Guatemala
n surgeon Aldo R. Casteneda.
By 1985, the arterial switch had become the procedure of choice, and remains the standard modern procedure for d-TGA repair. Atrial switches are still occasionally used as a standby when coronary artery patterns contraindicate coronary anastomoses, in cases of delayed diagnosis where pulmonary artery banding is not possible, and when a d-TGA + VSD patient also has left ventricular outflow tract obstruction.
The world's smallest infant to survive an arterial switch was Jerrick De Leon, born 13 weeks premature. At the time of the operation on February 6, 2005, he weighed just over 1.5 pounds (700 grams).
Open Heart Surgery
Open Heart Surgery was released on August 8, 2000 by rock band Virginwool. The band signed to Breaking/Atlantic Records after initially beginning signed to Universal Records. The album was produced and mixed by Brad Wood....
surgical procedure used to correct dextro-transposition of the great arteries
Dextro-Transposition of the great arteries
dextro-Transposition of the great arteries , sometimes also referred to as complete transposition of the great arteries, is a birth defect in the large arteries of the heart...
(d-TGA); its development was pioneered by Canadian cardiac
Cardiology
Cardiology is a medical specialty dealing with disorders of the heart . The field includes diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology...
surgeon William Mustard
William Mustard
William Thornton Mustard, was a Canadian physician and cardiac surgeon. In 1949, he was one of the first to perform open-heart surgery using a mechanical heart pump and biological lung on a dog at the Banting Institute...
and it was named for Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
ian cardiac surgeon Adib Jatene, who was the first to use it successfully. It was the first method of d-TGA repair to be attempted, but the last to be put into regular use because of technological
Technology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...
limitations at the time of its concept
Concept
The word concept is used in ordinary language as well as in almost all academic disciplines. Particularly in philosophy, psychology and cognitive sciences the term is much used and much discussed. WordNet defines concept: "conception, construct ". However, the meaning of the term concept is much...
ion. Use of the arterial switch is historically preceded by two atrial switch methods: the Senning
Senning procedure
Senning procedure is a surgical technique named after its inventor, the Swedish cardiac surgeon Åke Senning , also known for implanting the first permanent cardiac pacemaker in 1958.- Brief History :...
and Mustard procedure
Mustard procedure
The Mustard procedure was developed in 1963 by Dr. William Mustard at the Hospital for Sick Children in Toronto, Canada.Dr. Mustard, with support from the Heart and Stroke Foundation of Canada, developed the first operation to correct a congenital heart defect that produced “blue babies”. The...
s.
This surgery may be used in combination with other procedures for treatment of certain cases of double outlet right ventricle
Double outlet right ventricle
Double outlet right ventricle is a form of congenital heart disease where both of the great arteries connect to the right ventricle...
(DORV) in which the great arteries
Great arteries
Great arteries is a term used to refer collectively to the primary arteries of the heart, which include:* Pulmonary artery: the vessel that carries oxygen-depleted blood from the right ventricle to the lungs....
are dextro-transposed.
Timing
The Jatene procedure is ideally performed during the second week of life, before the left ventricleLeft ventricle
The left ventricle is one of four chambers in the human heart. It receives oxygenated blood from the left atrium via the mitral valve, and pumps it into the aorta via the aortic valve.-Shape:...
adjusts to the lower pulmonary pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
and is therefore unable to support the systemic circulation
Systemic circulation
Systemic circulation is the part of the cardiovascular system which carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart. This physiologic theory of circulation was first described by William Harvey...
. In the event of sepsis
Sepsis
Sepsis is a potentially deadly medical condition that is characterized by a whole-body inflammatory state and the presence of a known or suspected infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues...
or delayed diagnosis
Diagnosis
Diagnosis is the identification of the nature and cause of anything. Diagnosis is used in many different disciplines with variations in the use of logics, analytics, and experience to determine the cause and effect relationships...
, a combination of pulmonary artery banding
Pulmonary artery banding
Pulmonary Artery Banding , is a palliative surgical procedure used in the treatment of congenital heart defects. The technique is used in the treatment of infants with pulmonary overcirculation until more definitive repairs can be made.-History:...
(PAB) and shunt
Shunt (medical)
In medicine, a shunt is a hole or a small passage which moves, or allows movement of fluid from one part of the body to another. The term may describe either congenital or acquired shunts; and acquired shunts may be either biological or mechanical.* Cardiac shunts may be described as...
construction may be used to increase the left ventricular mass sufficiently to make an arterial switch possible later in infancy
Infant
A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...
.
Prognosis
The success of this procedure is largely dependent on the facilities available, the skill and experience of the surgeon, and the general health of the patientPatient
A patient is any recipient of healthcare services. The patient is most often ill or injured and in need of treatment by a physician, advanced practice registered nurse, veterinarian, or other health care provider....
. Under preferable conditions, the intra-operative and post-operative success rate is 96% or more, with a comparable survival rate after 5 years. Approximately 10% of arterial switch recipients develop residual pulmonary stenosis
Stenosis
A stenosis is an abnormal narrowing in a blood vessel or other tubular organ or structure.It is also sometimes called a stricture ....
post-operatively, which can lead to right heart
Right heart
Right heart is a term used to refer collectively to the right atrium and right ventricle of the heart; occasionally, this term is intended to reference the right atrium, right ventricle, and the pulmonary trunk collectively....
failure if left untreated; treatment usually involves endovascular stenting and/or xenograft patching.
Overview
- General anaesthesiaGeneral anaesthesiaGeneral anaesthesia is a state of unconsciousness and loss of protective reflexes resulting from the administration of one or more general anaesthetic agents...
and cardiopulmonary bypass are used. - The aortaAortaThe aorta is the largest artery in the body, originating from the left ventricle of the heart and extending down to the abdomen, where it branches off into two smaller arteries...
and pulmonary arteryPulmonary arteryThe pulmonary arteries carry deoxygenated blood from the heart to the lungs. They are the only arteries that carry deoxygenated blood....
are detached from their native rootRootIn vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s and reattached to the opposite root; thus, the pulmonary root becomes the neo-aorta, and the aortic root becomes the neo-pulmonary artery. - The coronary arteries are transplantOrgan transplantOrgan transplantation is the moving of an organ from one body to another or from a donor site on the patient's own body, for the purpose of replacing the recipient's damaged or absent organ. The emerging field of regenerative medicine is allowing scientists and engineers to create organs to be...
ed from the aorta/neo-pulmonary artery to the pulmonary artery/neo-aorta. - Length of procedure, from initiation of anaesthesia to post-operative cease thereof, is approximately 6–8 hours.
Preparatory
If the procedure is anticipated far enough in advance (with prenatal diagnosis, for example), and the individual's bloodBlood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
type is known, a family member with a compatible blood type
Blood type
A blood type is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells . These antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system...
may donate
Blood donation
A blood donation occurs when a person voluntarily has blood drawn and used for transfusions or made into medications by a process called fractionation....
some or all of the blood needed for transfusion
Blood transfusion
Blood transfusion is the process of receiving blood products into one's circulation intravenously. Transfusions are used in a variety of medical conditions to replace lost components of the blood...
during the use of a heart-lung machine
Heart-lung machine
Cardiopulmonary bypass is a technique that temporarily takes over the function of the heart and lungs during surgery, maintaining the circulation of blood and the oxygen content of the body. The CPB pump itself is often referred to as a heart–lung machine or "the pump"...
(HLM). The patient's mother
Mother
A mother, mum, mom, momma, or mama is a woman who has raised a child, given birth to a child, and/or supplied the ovum that grew into a child. Because of the complexity and differences of a mother's social, cultural, and religious definitions and roles, it is challenging to specify a universally...
is normally unable to donate blood for the transfusion, as she will not be able to donate blood during pregnancy
Pregnancy
Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
(due to the needs of the fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
) or for a few weeks after giving birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
(due to blood loss), and the process of collecting a sufficient amount of blood may take several weeks to a few months. However, in cases where the individual has been diagnosed but surgery must be delayed, maternal (or even autologous, in certain cases) blood donation may be possible, as long as the mother has a compatible blood type. In most cases, though, the patient receives a donation from a blood bank
Blood bank
A blood bank is a cache or bank of blood or blood components, gathered as a result of blood donation, stored and preserved for later use in blood transfusion. The term "blood bank" typically refers to a division of a hospital laboratory where the storage of blood product occurs and where proper...
. A blood transfusion is necessary for the arterial switch because the HLM needs its "circulation" filled with blood and an infant does not have enough blood on their own to do this (in most cases, an adult would not require blood transfusion).
The patient will require a number of imaging
Medical imaging
Medical imaging is the technique and process used to create images of the human body for clinical purposes or medical science...
procedures in order to determine the individual anatomy
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
of the great arteries and, most importantly, the coronary arteries. These may include angiography, magnetic resonance imaging
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(MRI), and/or computed tomography
Computed tomography
X-ray computed tomography or Computer tomography , is a medical imaging method employing tomography created by computer processing...
(CT scan). The coronary arteries are carefully mapped out in order to avoid unexpected intra-operative complications in transferring them from the native aorta to the neo-aorta.
Pre-operative
As with any procedure requiring general anaesthesia, arterial switch recipients will need to fast for several hours prior to the surgery to avoid the risk of chokingAsphyxia
Asphyxia or asphyxiation is a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally. An example of asphyxia is choking. Asphyxia causes generalized hypoxia, which primarily affects the tissues and organs...
on vomit while unconscious.
After the patient is anesthetized, they receive the following drugs
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...
via intravenous drip, which continue as necessary throughout the procedure:
- AprotininAprotininThe drug aprotinin , is the bovine version of the small protein basic pancreatic trypsin inhibitor, or BPTI, which inhibits trypsin and related proteolytic enzymes. Under the trade name Trasylol, aprotinin was used as a medication administered by injection to reduce bleeding during complex surgery,...
, to prevent excessive bleedingBleedingBleeding, technically known as hemorrhaging or haemorrhaging is the loss of blood or blood escape from the circulatory system... - MethylprednisoloneMethylprednisoloneMethylprednisolone is a synthetic glucocorticoid or corticosteroid drug. It is marketed in the USA and Canada under the brand names Medrol and Solu-Medrol. It is also available as a generic drug....
, to reduce swellingEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
and inflammationInflammationInflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process... - PhentolaminePhentolaminePhentolamine is a reversible nonselective alpha-adrenergic antagonist. -Mechanism:Its primary action is vasodilation due to α1 blockade....
, to prevent hypertensionHypertensionHypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and... - Prophylactic antibiotics, to prevent infectionInfectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
Intra-operative
The heart is accessed via median sternotomyMedian sternotomy
Median sternotomy is a type of surgical procedure in which a vertical inline incision is made along the sternum, after which the sternum itself is divided, or "cracked"...
, and the patient is given heparin
Heparin
Heparin , also known as unfractionated heparin, a highly sulfated glycosaminoglycan, is widely used as an injectable anticoagulant, and has the highest negative charge density of any known biological molecule...
to prevent the blood from clotting. A generous section of pericardium
Pericardium
The pericardium is a double-walled sac that contains the heart and the roots of the great vessels.-Layers:...
is harvested, then disinfected and sterilized
Sterilization (microbiology)
Sterilization is a term referring to any process that eliminates or kills all forms of microbial life, including transmissible agents present on a surface, contained in a fluid, in medication, or in a compound such as biological culture media...
with a weak solution of glutaraldehyde
Glutaraldehyde
Glutaraldehyde is an organic compound with the formula CH22. A pungent colorless oily liquid, glutaraldehyde is used to disinfect medical and dental equipment...
; and the coronary and great artery anatomy are examined. The ductus arteriosus
Ductus arteriosus
In the developing fetus, the ductus arteriosus , also called the ductus Botalli, is a shunt connecting the pulmonary artery to the aortic arch. It allows most of the blood from the right ventricle to bypass the fetus's fluid-filled lungs. Upon closure at birth, it becomes the ligamentum arteriosum...
and right pulmonary branch, up to and including the first branches in the hilum
Hilum of lung
Above and behind the cardiac impression is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These include the pulmonary artery, superiormost on the left lung, the superior and inferior pulmonary veins, lymphatic vessels and...
of the right lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
, are separated from the surrounding supportive tissue
Biological tissue
Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
to allow mobility of the vessels
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
. Silk
Silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...
marking sutures may be placed in the pulmonary trunk at this time, to indicate the commissure of the aorta to the neo-aorta; alternatively, this may be done later in the procedure.
The cardiopulmonary bypass is then initiated by inserting a cannula
Cannula
A cannula or canula is a tube that can be inserted into the body, often for the delivery or removal of fluid or for the gathering of data...
into the ascending aorta
Ascending aorta
The ascending aorta is a portion of the aorta commencing at the upper part of the base of the left ventricle, on a level with the lower border of the third costal cartilage behind the left half of the sternum; it passes obliquely upward, forward, and to the right, in the direction of the heart’s...
as distally from the aortic root as possible while still supplying all arterial
Artery
Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries....
branches, another cannula is inserted into the right atrium
Right atrium
The right atrium is one of four chambers in the hearts of mammals and archosaurs...
, and a vent is created for the left ventricle
Left ventricle
The left ventricle is one of four chambers in the human heart. It receives oxygenated blood from the left atrium via the mitral valve, and pumps it into the aorta via the aortic valve.-Shape:...
via catheterization of the right superior pulmonary vein. The HLM is started at a low-flow
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
and the patient's body
Body
With regard to living things, a body is the physical body of an individual. "Body" often is used in connection with appearance, health issues and death...
is cooled to a rectal temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
of 20 °
Degree (temperature)
The term degree is used in several scales of temperature. The symbol ° is usually used, followed by the initial letter of the unit, for example “°C” for degree Celsius...
C
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
(68 °F
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...
), which prevents the brain damage
Brain damage
"Brain damage" or "brain injury" is the destruction or degeneration of brain cells. Brain injuries occur due to a wide range of internal and external factors...
otherwise associated with the temporary circulatory arrest
Cardiac arrest
Cardiac arrest, is the cessation of normal circulation of the blood due to failure of the heart to contract effectively...
necessary during the procedure; the patient must be cooled for a minimum of 20 minutes prior to beginning the repair.
While the patient is cooling, the ductus arteriosus is ligated
Ligature (medicine)
In surgery or medical procedure, a ligature consists of a piece of thread tied around an anatomical structure, usually a blood vessel or another hollow structure to shut it off. With a blood vessel the surgeon will clamp the vessel perpendicular to the axis of the artery or vein with a hemostat,...
at both the aortic and pulmonary ostia, then transected at its center; the left pulmonary branch, including the first branches in the hilum of the left lung, is separated from the supportive tissue; and the aorta is marked at the site it will be transected, which is just below the pulmonary bifurcation, proximal to where the pulmonary artery will be transected.
When the patient is fully cooled, the ascending aorta is clamped as close as possible below the HLM cannula, and cryocardioplegia is achieved by delivering cold blood to the heart via the ascending aorta (below the cross clamp). The aorta is then transected at the marked spot, and the pulmonary artery is transected a few millimetres below the bifurcation. The vessels are again examined, and the pulmonary root is inspected for left ventricular outflow tract obstruction (LVOTO). If a ventricular septal defect
Ventricular septal defect
A ventricular septal defect is a defect in the ventricular septum, the wall dividing the left and right ventricles of the heart.The ventricular septum consists of an inferior muscular and superior membranous portion and is extensively innervated with conducting cardiomyocytes.The membranous...
(VSD) is present, it may be repaired, at this point via either the aortic
Aortic valve
The aortic valve is one of the valves of the heart. It is normally tricuspid , although in 1% of the population it is found to be congenitally bicuspid . It lies between the left ventricle and the aorta....
or pulmonary valve
Pulmonary valve
The pulmonary valve is the semilunar valve of the heart that lies between the right ventricle and the pulmonary artery and has three cusps. Similar to the aortic valve, the pulmonary valve opens in ventricular systole, when the pressure in the right ventricle rises above the pressure in the...
; it may alternatively be repaired later in the procedure.
The great arteries are usually arranged using the Lecompte maneuver, with the aortic cross clamp positioned to hold the pulmonary artery anterior to the ascending aorta; though with some congenital arrangements of the great arteries, such as side-by-side, this is not possible and the arteries will be transplanted in the non-anatomic 'anterior aorta' arrangement. If the aortic commissure has not yet been marked, it may be done at this point, using the same method as would be used prior to bypass; however, there is a third opportunity for this still later in the procedure.
Coronary arteries are examined closely, and the ostia and proximal arterial course are identified, as are any infundibular branches, if they exist. The coronary ostia and a large "button" of surrounding aortic wall are then excised from the aorta, well into the sinus of Valsalva; and the proximal sections of the coronary arteries are separated from the surface of the heart, which prevents tension
Tension (mechanics)
In physics, tension is the magnitude of the pulling force exerted by a string, cable, chain, or similar object on another object. It is the opposite of compression. As tension is the magnitude of a force, it is measured in newtons and is always measured parallel to the string on which it applies...
or distortion
Distortion
A distortion is the alteration of the original shape of an object, image, sound, waveform or other form of information or representation. Distortion is usually unwanted, and often many methods are employed to minimize it in practice...
after anastomosis
Anastomosis
An anastomosis is the reconnection of two streams that previously branched out, such as blood vessels or leaf veins. The term is used in medicine, biology, mycology and geology....
to the neo-aorta. Infundibular branches are sometimes unable to be spared, but this is a very rare occurrence. If the aortic commissure has not previously been marked, the excised coronary arteries will be used to determine the implant
Implant
Implant can refer to:*Implant , or specifically:**Brain implant**Breast implant**Buttock implant**Cochlear implant**Contraceptive implant**Dental implant**Mini dental implant**Extraocular implant**Fetal tissue implant...
ation position of the aorta.
The aorta is then transplanted onto the pulmonary root, using either absorbable or permanent continuous suture. The aortic clamp is temporarily removed while small sections of the neo-aorta are cut away to accommodate the coronary ostia, and a continuous absorbable suture is then used to anastomose each coronary "button" into the prepared space. In most cases, the coronary implantation sites will be at left and right anterior positions at the base of the neo-aorta; however, if the circumflex coronary artery branches from the right coronary artery
Right coronary artery
The right coronary artery originates above the right cusp of the aortic valve. It travels down the right atrioventricular groove, towards the crux of the heart.At the origin of the RCA is the conus artery....
, the circumflex coronary artery will be distorted if the pair are not implanted higher than normal on the neo-aorta, and in some cases they may need to be implanted above the aortic commissure, on the native aorta itself. The circumflex coronary artery may originate from the same coronary sinus as, rather than directly from, the right coronary artery, in which case they may still be excised on the same "button" and transplanted similarly to if they had a shared ostium, unless one or both have intramural communication with another coronary vessel. Sometimes, one or more coronary ostia are located very close to the valvular
Heart valve
A heart valve normally allows blood flow in only one direction through the heart. The four valves commonly represented in a mammalian heart determine the pathway of blood flow through the heart...
opening and a small portion of the native aortic valve must be removed when the coronary artery is excised, which causes a generally mild, and usually well-tolerated
Physiological tolerance
Physiological tolerance or drug tolerance is commonly encountered in pharmacology, when a subject's reaction to a drug is reduced at a later time even though the dose or concentration at the effect site is the same. This means that larger doses are required to achieve the same effect...
, neo-pulmonary valve regurgitation
Aortic insufficiency
Aortic insufficiency , also known as aortic regurgitation , is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle....
.
The HLM is turned off and the aortic and atrial cannula are removed, then an incision is made in the right atrium, through which the congenital or palliative atrial septal defect
Atrial septal defect
Atrial septal defect is a form of congenital heart defect that enables blood flow between the left and right atria via the interatrial septum. The interatrial septum is the tissue that divides the right and left atria...
(ASD) is repaired; where a Rashkind balloon atrial septostomy
Rashkind balloon atrial septostomy
The Rashkind balloon atrial septostomy is a medical procedure, performed during cardiac catheterization , in which a balloon catheter is used to enlarge a foramen ovale, patent foramen ovale , or atrial septal defect in order to increase oxygen saturation in patients with cyanotic congenital heart...
was used, the ASD should be able to be closed with sutures, but cases involving large congenital ASDs or Blalock-Hanlon atrial septectomy, a pericardial, xenograft, or Dacron patch may be necessary. If there is a VSD which has not yet been repaired, this is performed via the atrial incision and tricuspid valve
Tricuspid valve
The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, between the right atrium and the right ventricle. The normal tricuspid valve usually has three leaflets and three papillary muscles. They are connected to the papillary muscles by the chordae...
, using sutures for a small defect or a patch for a large defect.
When the septal defects have been repaired and the atrial incision is closed, the previously removed cannula are replaced and the HLM is restarted. The left ventricle is then vented and the cross clamp removed from the aorta, enabling full-flow to be re-established and rewarming to begin; at this point the patient will receive an additional dose of Regatine to keep blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
under control. The previously harvested pericardium is then used to patch the coronary explantation sites, and to extend - and widen, if necessary - the neo-pulmonary root, which allows the pulmonary artery to be anastamosed without residual tension; the pulmonary artery is then transplanted to the neo-pulmonary root.
Final stages
The patient is fitted with chest tubeChest tube
A chest tube is a flexible plastic tube that is inserted through the side of the chest into the pleural space. It is used to remove air or fluid , or pus from the intrathoracic space...
s, temporary pacemaker
Artificial pacemaker
A pacemaker is a medical device that uses electrical impulses, delivered by electrodes contacting the heart muscles, to regulate the beating of the heart...
leads, and ventilated before weaning from the HLM is begun; and administration of post-operative drugs is initiated, these include:
- muscle relaxantMuscle relaxantA muscle relaxant is a drug which affects skeletal muscle function and decreases the muscle tone. It may be used to alleviate symptoms such as muscle spasms, pain, and hyperreflexia. The term "muscle relaxant" is used to refer to two major therapeutic groups: neuromuscular blockers and spasmolytics...
, to induce temporary paralysisParalysisParalysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed... - opioidOpioidAn opioid is a psychoactive chemical that works by binding to opioid receptors, which are found principally in the central and peripheral nervous system and the gastrointestinal tract...
analgesicAnalgesicAn analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
, to manage pain, cause sedationSedationSedation is the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure...
and induce serenity - inotropeInotropeAn inotrope is an agent that alters the force or energy of muscular contractions. Negatively inotropic agents weaken the force of muscular contractions...
, to assist the heart in contractingMuscle contractionMuscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten, or remain the same...
adequately
The rib cage
Rib cage
The rib cage is an arrangement of bones in the thorax of animals. It is formed by the vertebral column, ribs and sternum and encloses the heart and lungs....
is relaxed and the external surgical wound
Wound
A wound is a type of injury in which skin is torn, cut or punctured , or where blunt force trauma causes a contusion . In pathology, it specifically refers to a sharp injury which damages the dermis of the skin.-Open:...
is bandaged, but the sternum and chest incision are left open to provide extra room in the pleural cavity
Pleural cavity
In human anatomy, the pleural cavity is the potential space between the two pleura of the lungs. The pleura is a serous membrane which folds back onto itself to form a two-layered, membrane structure. The thin space between the two pleural layers is known as the pleural cavity; it normally...
, allowing the heart room to swell and preventing pressure caused by pleural effusion
Pleural effusion
Pleural effusion is excess fluid that accumulates between the two pleural layers, the fluid-filled space that surrounds the lungs. Excessive amounts of such fluid can impair breathing by limiting the expansion of the lungs during ventilation.-Pathophysiology:...
.
Post-operative
The sternum and chest can usually be closed within a few days; however, the chest tubes, pacemaker, ventilator, and drugs may still be required after this time. The patient will continue to fast for up to a few days, and breastmilk or infant formulaInfant formula
Infant formula is a manufactured food designed and marketed for feeding to babies and infants under 12 months of age, usually prepared for bottle-feeding or cup-feeding from powder or liquid . The U.S...
can then be gradually introduced via nasogastric tube (NG tube); the primary goal after a successful arterial switch, and before hospital
Hospital
A hospital is a health care institution providing patient treatment by specialized staff and equipment. Hospitals often, but not always, provide for inpatient care or longer-term patient stays....
discharge, is for the infant
Infant
A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...
to gain back the weight they have lost and continue to gain weight at a normal or near-normal rate.
History
ScottishScotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
pathologist Matthew Baillie
Matthew Baillie
Matthew Baillie was a Scottish physician and pathologist.-Life:...
first described TGA in 1797, presumably as a posthumous diagnosis. Early mortality rates
Mortality rate
Mortality rate is a measure of the number of deaths in a population, scaled to the size of that population, per unit time...
at this time are estimated to have been as high as 90%; the survivors would have been those with one or more concomitant intracardiac shunts
Shunt (medical)
In medicine, a shunt is a hole or a small passage which moves, or allows movement of fluid from one part of the body to another. The term may describe either congenital or acquired shunts; and acquired shunts may be either biological or mechanical.* Cardiac shunts may be described as...
(ASD, patent ductus arteriosus
Patent ductus arteriosus
Patent ductus arteriosus is a congenital disorder in the heart wherein a neonate's ductus arteriosus fails to close after birth. Early symptoms are uncommon, but in the first year of life include increased work of breathing and poor weight gain...
(PDA), patent foramen ovale (PFO), and/or VSD), and are unlikely to have survived past adolescence
Adolescence
Adolescence is a transitional stage of physical and mental human development generally occurring between puberty and legal adulthood , but largely characterized as beginning and ending with the teenage stage...
.
In 1950, American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
surgeons Alfred Blalock
Alfred Blalock
Alfred Blalock was a 20th-century American surgeon most noted for his research on the medical condition of shock and the development of the Blalock-Taussig Shunt, surgical relief of the cyanosis from Tetralogy of Fallot—known commonly as the blue baby syndrome—with Vivien Thomas and pediatric...
and C. Rollins Hanlon introduced the Blalock-Hanlon atrial septectomy, which was then routinely used to palliate patients. This would have effectively reduced early mortality rates, particularly in cases with no concomitant shunts, but is unlikely to have reduced late mortality rates.
Mustard first conceived of, and attempted, the anatomical repair (arterial switch) for d-TGA in the early 1950s. His few attempts were unsuccessful due to technical difficulties posed by the translocation of the coronary arteries, and the idea was abandoned.
Swedish cardiac surgeon Åke Senning
Åke Senning
Åke Senning was a pioneering Swedish cardiac surgeon, who implanted the first human implantable cardiac pacemaker in 1958, invented the Senning operation, and contributed to many other advances....
described the first corrective surgery for d-TGA (the Senning procedure) in 1959, which involved using the atrial septum to create an intratrial baffle
Baffle
Baffle or baffles may refer to:* Baffle , a flow-directing vane or panel in some vessels such as shell and tube heat exchangers, chemical reactors, or static mixers...
that redirected bloodflow
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
at the atrial
Atrium (anatomy)
In anatomy, the atrium , sometimes called auricle , refers to a chamber or space. For example, the term is used for a portion of the lateral ventricle in the brain and the blood collection chamber of the heart...
level; Senning yielded a high success rate using this procedure, significantly lowering both early and late mortality rates.
Due to the technical complexity of the Senning procedure, others could not duplicate his success rate; in response, Mustard developed a simpler alternative method (the Mustard procedure) in 1964, which involved constructing a baffle from autologous pericardium
Pericardium
The pericardium is a double-walled sac that contains the heart and the roots of the great vessels.-Layers:...
or synthetic
Synthetic fiber
Synthetic fibers are the result of extensive research by scientists to improve on naturally occurring animal and plant fibers. In general, synthetic fibers are created by forcing, usually through extrusion, fiber forming materials through holes into the air, forming a thread...
material, such as Dacron. This procedure yielded early and late mortality rates comparable to the Senning procedure; however, a late morbidity rate was eventually discovered in relation to the use of synthetic graft material, which does not grow with the recipient and eventually causes obstruction.
In 1966, American surgeons William Rashkind and William Miller transformed the palliation of d-TGA patients with the innovative Rashkind balloon atrial septostomy, which, unlike the thoracotomy
Thoracotomy
Thoracotomy is an incision into the pleural space of the chest. It is performed by a surgeon, and, rarely, by emergency physicians, to gain access to the thoracic organs, most commonly the heart, the lungs, the esophagus or thoracic aorta, or for access to the anterior spine such as is necessary...
required by a septectomy, is performed through the minimally invasive surgical technique of cardiac catheterization
Cardiac catheterization
Cardiac catheterization is the insertion of a catheter into a chamber or vessel of the heart. This is done for both investigational and interventional purposes...
.
Although the atrial switch procedures dramatically reduced both early and late mortality rates, these statistics remained high, partly due to the wait time required between birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
and surgery (pre-operative mortality: 5-10%; early mortality: 0-15%; late mortality: 20-25%). A concomitant VSD raises the early mortality rate for atrial switch to 10-60%, even in cases where the VSD is repaired. The late morbidity rate is also very high in atrial switch recipients, with 13-100% developing post-operative complications related to intra-operative damage caused to the sinus node and/or the inherent unsuitability of the heart chamber
Heart chamber
aHeart chamber is a general term used to refer to any chambers of the mammalian heart. The heart consists of four chambers: the right and left atrium and the right and left ventricle. The top chambers are connected to the bottom chambers by valves and are separated by the coronary sulcus...
s for role reversal.
These statistics, combined with advances in microvascular surgery, created a renewed interest in Mustard's original concept of an arterial switch procedure. The first successful arterial switch was performed on a forty-two day old d-TGA + VSD infant by Jatene in 1975. Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
ian cardiac surgeon Magdi Yacoub
Magdi Yacoub
Sir Magdi Habib Yacoub, FRS , is Professor of Cardiothoracic Surgery at Imperial College London.Yacoub's major achievements may be summarised:1. Established Heart Transplantation in UK and became leading transplant surgeon in the world....
was subsequently successful in treating TGA with intact septum when preceded by pulmonary artery banding and systemic-to-pulmonary shunt palliation. Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
n surgeon B. Eber was the first to recount a small series of successful arterial switch procedures, and the first large successful series was reported by Guatemala
Guatemala
Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...
n surgeon Aldo R. Casteneda.
By 1985, the arterial switch had become the procedure of choice, and remains the standard modern procedure for d-TGA repair. Atrial switches are still occasionally used as a standby when coronary artery patterns contraindicate coronary anastomoses, in cases of delayed diagnosis where pulmonary artery banding is not possible, and when a d-TGA + VSD patient also has left ventricular outflow tract obstruction.
The world's smallest infant to survive an arterial switch was Jerrick De Leon, born 13 weeks premature. At the time of the operation on February 6, 2005, he weighed just over 1.5 pounds (700 grams).