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Pediatric Cardiac Anesthesia: An Overview
Sana Ullah, M.D., Ch.B.; Pediatric
Anesthesiologist; Arkansas Children's Hospital; Assistant
Professor of Anesthesiology; Pediatric and Congenital Cardiothoracic
Anesthesiology
There is probably no other surgical specialty where a successful
outcome depends so much on good teamwork than congenital
cardiac surgery. Around the time of surgery, the core of
this team consists of surgeons, anesthesiologists, perfusionists
and critical care physicians. The role of an anesthesiologist
is generally perceived as keeping the patient asleep and
pain-free while surgery is taking place. In pediatric heart
surgery, the anesthesiologist assumes an even more important
role in facilitating surgery, monitoring, and optimizing
vital organ function – particularly during the time
the patient is on the heart-lung machine. It is widely acknowledged
that in the current era it is possible to do a technically
excellent operation due to advances in diagnosis and microsurgery
technology. The focus has now shifted in trying to minimize
damage to vital organs other than the heart – primarily
the brain, kidneys and lungs. It can be very disheartening
to perform a technically excellent operation and then have
the patient develop severe brain, renal or lung dysfunction
post-operatively. Fortunately, this is a rare occurrence.
The anesthesiologist works in close co-operation with all
the other members of the surgical team to ensure the best
possible outcome for the patient.
In the Children’s Heart Center at Arkansas Children's
Hospital, there are four full-time pediatric cardiac anesthesiologists
who take care of patients with congenital heart disease whether
they are having cardiac or non-cardiac surgery. The anesthesiologist
will meet with the patient and parents usually the day before
surgery to conduct a detailed interview and physical examination.
One of the most interesting aspects of congenital heart disease
(CHD) is that the age of the
patients will vary from newborn babies to patients in their
twenties or thirties. Because of better outcomes, more patients
with CHD are surviving to adulthood and this has led to a
separate population of “adults with CHD” with
their own set of unique problems. CHD often occurs in combination
with abnormalities of other organ systems, and the preoperative
interview allows the anesthesiologist to detect these problems
and plan for them. A detailed anesthetic plan is then presented,
the main points of which are:
- Preoperative Fasting: Solid food and formula
milk are generally stopped six hours before surgery.
Breast milk can be given up to four hours and clear
liquids may be taken up to two hours before surgery.
The “nil by mouth” guidelines have
been liberalized over the past few years as this
is more comfortable for patients and minimizes
the chance of dehydration. Patients who are admitted
to the hospital on the day before surgery (these
are generally cyanotic patients) may have intravenous
fluids started the night before surgery to ensure
adequate hydration, because cyanosis generally
causes polycythemia (increased red blood cell production),
which increases the viscosity (sludginess) of the
blood. This can lead to decreased organ perfusion
and increases the risk of thrombosis.
- Premed: Patients who are going to have surgery
on cardiopulmonary bypass (the heart-lung machine)
are given a steroid called dexamethasone the night
before surgery. An additional dose is given at
anesthetic induction. This helps to reduce the general
inflammatory response to cardiac surgery. Patients are
also given a sedative premed thirty minutes before surgery
to reduce anxiety and facilitate anesthetic induction.
In many cases, parents also look like they might
benefit from some sedation! Children are very astute
at picking up emotional cues from their parents
and parental anxiety is easily transmitted to the patient
who is about to go to the operating room. Even
though this can be a very stressful time for the family,
it is important to have calm and relaxed parents
when the patient is being taken to the operating
room.
- Anesthetic Management: Patients without
an IV are anesthetized by breathing the anesthetic
gases from a mask placed over the mouth and nose.
This takes a few minutes, and once unconsciousness
is achieved an IV and other monitoring lines are
placed. A breathing tube is placed through the
nose or mouth depending on the age of the patient. An
arterial line and a central line is inserted, and
in most cases an echo probe is placed in the esophagus
to assess the repair after the patient is taken
off the heart-lung machine. Most surgeries last four
to six hours, but may be longer in the case of
re-operations. The patient is then transferred to the
Intensive Care Unit (ICU), and depending on various patient
factors may be taken off the respirator within
a few hours. Some patients may require a longer period
of artificial respiration. These are generally
smaller babies and more complex operations. All patients
are given a morphine infusion for pain control
and sedation. Blood products may be given for excessive
bleeding or abnormal clotting, but our aim is to
minimize exposure to all blood products. The ICU
is in many ways an extension of the OR and all
the body’s vital organs are closely monitored.
Physicians with specialized training in intensive
care generally take over the care once the patients
are transferred to the ICU. Parents are kept updated
regularly and are encouraged to be with their children
for as long as they wish.
- Cardiopulmonary Bypass (CPB): This is also
known as the heart-lung machine. Most cardiac surgeries
require the patient to be placed on CPB. This consists
of an artificial lung to add oxygen and remove
carbon dioxide, and a pump to move blood around the rest
of the body while the surgeon is operating on the
heart itself. CPB has been around for almost 50
years and although considered very safe can be the source
of some problems encountered during heart surgery.
These include fluid overload, a whole body inflammatory
response, injury to the nervous system and other
vital organs and bleeding. Many recent innovations
and advances have been designed to minimize the
complications of CPB. These include new techniques to
monitor brain oxygenation, specific drugs to minimize
the inflammatory response and reduce bleeding and techniques
to remove excess fluid from the body at the end of surgery
(known as “modified ultrafiltration” or
MUF). Some of these issues will be covered in future
issues of this newsletter.
Cardiac surgery can be a very stressful time for the patients
and their parents. The anesthesiologists at the Children’s
Heart Center are part of a whole team focused on achieving
the best possible outcomes for all patients who require their
services.
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Fetal Echocardiography
Renee Bornemeier, M.D.; Physician,
Pediatric Cardiology; Arkansas Children's Hospital; Associate
Professor of Pediatric Medicine; University of Arkansas
for Medical Sciences College of Medicine
As you might be able to tell from looking at this Web site
or our newsletter, our mission is to provide excellent care
to our patients with heart problems and their families. But
did you know that you don’t even have to be born to
be one of our heart patients? Each year many babies
are diagnosed prior to birth with cardiac defects by undergoing
a fetal echocardiogram.
What is a fetal echocardiogram?
A fetal echocardiogram is a highly specialized type
of prenatal ultrasound. It is performed to evaluate
the structure of the heart of the unborn child. This
type of study is usually performed between 20 to 25weeks
of gestation. Obstetricians and family practice physicians
are all trained to get the typical “four-chamber view” of
the heart. However, a fetal echocardiogram is much more comprehensive
than this. It evaluates the position of the abdominal organs
and the heart, as well as, the anatomy of the heart itself. The
traditional four-chamber view of the heart is usually the
best place to start. The heart rate, chamber sizes, cardiac
valves, cardiac septae, venous returns and the great arteries
can all be evaluated. Many additional views are also utilized
to look at the cardiac structures from multiple planes and
perspectives.
Who should receive a fetal echocardiogram?
Women with certain types of medical conditions carry
a higher risk for having a baby with a congenital cardiac
defect. These women may benefit from having a fetal
echocardiogram. Type 1 diabetes, autoimmune disorders,
exposure to certain drugs or medications during the stage
of organ development early in pregnancy, some maternal
viral infections acquired during pregnancy and certain
genetic conditions can all increase the likelihood of a
congenital cardiac defect. Parents with a congenital
cardiac defect or a close family relative with a cardiac
defect is also another indication for a fetal echocardiogram.
Fetal conditions may be identified that would warrant a
fetal echocardiogram. Mid-line defects, abnormal karotypes,
two vessel umbilical cords, fetal hydrops (fluid collections
within the baby), cardiac arrhythmias and concerns that the
heart appears abnormal are all very good indications for
a fetal cardiac evaluation.
What are the limitations of this test?
This type of testing is very useful and in most cases
can assess the cardiac anatomy accurately. However, there
are some forms of congenital cardiac defects that may not
be able to be identified until after a baby is born. The
flow of blood through a baby’s heart prior to birth
is different than the flow through the heart after birth. Changes
occur in all babies at the time of birth allowing for a
transition between intrauterine life and extrauterine life.
Coarctation of the aorta, total anomalous pulmonary
venous return, coronary anomalies and some types of
septal and valvar defects may be difficult or impossible
to identify prior to birth.
Also be aware, the evaluation of the anatomy is only
as good as the images. Some women do not make
as good high resolution ultrasound images as others;
and therefore, the anatomy may not be able to be as
clearly defined. Imaging later in gestation also
limits the imaging plane and quality of the images. As
gestation progresses and the fetus grows, the fetal
positions become less varied and the ribs begin to
calcify – all limiting the imaging of the fetal
heart.
What happens if my unborn baby is identified
as having a cardiac defect?
Within the University of Arkansas for Medical Sciences
(UAMS)/Arkansas Children’s Hospital (ACH) system,
families identified as having a baby with a cardiac
defect receive comprehensive care. There is a
joint clinic at Freeway Medical Center where the UAMS
high risk obstetricians, pediatric cardiologists, genetic
counselors and ultrasound technicians work together
to provide these families with a comprehensive care
and delivery plan. The families receive counseling
by the pediatric cardiologist. The cardiac diagnosis
is explained. A diagrammatic picture of the heart is
drawn to help the families understand the cardiac problem.
A discussion is also held with
the families regarding what to expect at the time of
delivery and transfer to Arkansas Children’s
Hospital. An overview of what might be expected
for the global picture of this type of defect is also
given to the families.
Deliveries that need to be at a tertiary care center
are usually arranged at UAMS. The UAMS neonatologists
manage the infants at both UAMS and ACH. The neonatologists
receive the baby at the time of delivery and stabilize
the baby. The ACH transport team is notified and the
infant is transferred to ACH where a complete evaluation
is performed. Once the mother has had time to
stabilize post-delivery, she can come to ACH to be
with the baby. The families will meet many people involved
in the care of their child – surgeons, other
cardiologists, intensivists, nurse practitioners, nurses,
support staff and technicians – to name a few.
While infants are in the ICU, parents have a waiting
room with chairs that convert to beds, locker and showers. This
enables the family to be close to their infant. Support
services are available to the families including financial
counseling, social work, child life and lactation support.
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Coarctation of
the Aorta: Still Easy to Miss
Paul Seib, M.D.; Medical Director
of Cardiac Catherization Lab; Arkansas Children's
Hospital; Associate Professor of Pediatrics; Section
of Pediatric Cardiology; University of Arkansas for
Medical Sciences College of Medicine
Synonyms: LV outflow tract obstruction,
aortic arch obstruction, interrupted aortic arch
Background: Congenital heart disease
occurs in eight of every 1,000 live births and coarctation
of the aorta accounts for five to eight percent of
all congenital heart defects. Coarctation of the aorta
may occur as an isolated defect or in association with
a variety of other lesions, most commonly bicuspid
aortic valve and ventricular septal defect. The association
with bicuspid aortic valve has been estimated to range
from 13 to 85 percent. Even in the present era, the
diagnosis of coarctation of the aorta is often delayed
until the patient develops congestive heart failure
or hypertension. This overview will focus on the presentation,
clinical features and therapeutic options associated
with coarctation of the aorta.
Mortality/Morbidity: Autopsy studies
suggest that unoperated coarctation of the aorta carries
a 90 percent mortality by age 50 with a mean age of
death of 35 years. Mortality is often determined by
patient age, patient size and the presence or absence
of associated major cardiovascular anomalies. Associated
problems that may contribute to death or morbidity
include hypertension, intracranial hemorrhage, aortic
rupture or dissection, endocarditis and congestive
heart failure.
Race: No definitive racial differences
in the occurrence of coarctation of the aorta have
been documented; though some authors have suggested
that coarctation of the aorta occurs less commonly
in Asian people.
Sex: There is a marked male predominance
of coarctation of the thoracic aorta in a 2:1 male
to female ratio. This is not true for abdominal coarctation
of the aorta where females predominant in this very
rare lesion. Approximately one abdominal coarctation
of the aorta occurs for every 1,000 coarctations of
the thoracic aorta.
Age: In general, patients with coarctation
of the aorta may present early in life with congestive
heart failure or later in life with hypertension. Studies
continue to document that coarctation of the aorta
is often missed in the first year of life and the median
age of referral to a pediatric cardiologist in one
study was 5 years of age. Among 2,192 patients
reported to the Pediatric Cardiac Care Consortium for
the years 1985 to 1993, 1,337 were infants, 824 were
children and 31 were adults.
History: The history in patients
with coarctation is variable but may be related to
those patients who present early, often with congestive
heart failure and those who present later, most often
with hypertension.
Early presentation: Young patients may present in
the first three weeks of life with poor feeding, rapid
breathing, lethargy and progress to overt congestive
heart failure and shock. These patients may have appeared
well prior to hospital discharge with their deterioration
coincident with closure of the patent ductus arteriosus.
Development of symptoms is often accelerated by the
presence of associated major cardiac anomalies such
as ventricular septal defect. Such patients historically
have carried the highest risk of operation. Symptoms
may be subtle at first and patients may make repeated
trips to the physician before finally presenting in
critical condition.
Late presentation: Patients often present after the
first month of life with hypertension or a murmur. Such
patients have often not developed overt congestive
heart failure because of the presence of arterial vessels
that bypass the obstruction. Such patients may often
be diagnosed after hypertension is noted as an incidental
finding during evaluation of other problems such as
trauma or a more routine illness. Other presenting
symptoms may include headaches, chest pain, fatigue
or even life-threatening intracranial hemorrhage. True
lower extremity pain with exercise is rare. Many patients
are asymptomatic except for their incidentally noticed
hypertension.
Physical: As with the history, the
physical examination may be conveniently divided into
those patients presenting early with heart failure
and those who present later with hypertension.
Early presentation: Infants may present with tachycardia,
rapid and increased work of breathing, and even may
present moribund with shock. Keys to the diagnosis
include blood pressure discrepancies between the upper
and lower extremities as well as reduced or absent
lower extremity pulses to palpation. In the case
of aberrant origin of the right subclavian artery from
the aorta distal to the obstruction, such differences
may not be present though there will be reduced lower
extremity pulses compared to the carotid pulses.
Differential cyanosis (pink upper extremities with
cyanotic lower extremities) may occur when lower body
blood flow is provided by right to left flow across
a patent ductus arteriosus. This may be documented
by pre- and post-ductal pulse oximetry measurements
as well as by inspection. Reversed differential cyanosis
(upper body cyanosis with normal lower body saturation)
may occur with transposition of the great arteries,
patent ductus arteriosus and pulmonary hypertension
resulting in right to left ductal shunting.
In the case of the low cardiac output and ventricular
dysfunction, pulses may be diffusely diminished and
blood pressure gradients may seem minimal.
The murmur associated with coarctation of the aorta
may be non-specific but is usually a systolic murmur
in the left infraclavicular area as well as under the
left scapula. Additional murmurs due to the presence
of associated abnormalities, such as a ventricular
septal defect or aortic valve stenosis, may also be
detected. An ejection click may signify the presence
of a bicuspid aortic valve. A gallop rhythm may signify
ventricular dysfunction.
Late presentation: Older infants and children may
be referred for evaluation of hypertension or a murmur. Hypertension
in a fussy infant may be attributed to agitation and
thus it is important to compare four extremity blood
pressures. Occasionally, the left arm pressure may
be lower than the right arm pressure if the origin
of the left subclavian artery is involved in the coarctation. Careful
simultaneous palpation of upper and lower extremity
pulses may help confirm suspected coarctation.
A murmur in the left infraclavicular area as well
as under the left scapula may be systolic but may also
sound continuous in the presence of multiple collateral
vessels or occasionally in severe coarctation. An
ejection click may be present when there is an associated
bicuspid aortic valve as well as a murmur of aortic
stenosis or insufficiency. Similarly, a murmur
of mitral stenosis or LV outflow tract obstruction
may also occur. A gallop rhythm may occur in the presence
of a hypertrophic, non-compliant left ventricle.
Other abnormalities on physical exam may include abnormalities
of the blood vessels in the retina and a prominent
suprasternal notch pulsation. A thrill may be present
in the suprasternal notch or on the precordium in the
presence of significant aortic valve stenosis. In
the rare case of abdominal coarctation, an abdominal
bruit may be noted.
Causes: A number of theories have
been proposed to explain the occurrence of coarctation
of the aorta. These include postnatal ductal
constriction as well as a theory that alterations in
intrauterine blood flow result in altered flow through
the aortic arch and result in the substrate for coarctation. The
coarctation becomes manifest when the ductus closes.
Like most forms of congenital heart disease, multifactorial
influences seem to affect the occurrence and severity
of coarctation. These include genetic abnormalities
such as XO Turner Syndrome in which 15 to 20 percent
of the patients have coarctation of the aorta. There
are reported familial patterns of inheritance of coarctation
and other left heart obstructive lesions. An
increase in seasonal occurrence of coarctation of the
aorta has been noted in September and November.
Differential Diagnosis:
- Other LV outflow tract obstructive lesions – aortic
stenosis, subaortic stenosis, supravalve aortic stenosis,
Shone’s complex
- Mitral stenosis – mitral regurgitation
- Interrupted aortic arch
- Truncus arteriosus with interrupted aortic arch
- Hypoplastic left heart syndrome
- Aortic arch hypoplasia with complex congenital
heart disease
- Sepsis
- Metabolic disease
- Myocarditis
- Dilated cardiomyopathy
Laboratory Studies:
- Pre- and post-ductal pulse oximetry
- Neonatal patients presenting in shock
- Septic work-up to include blood, urine, and CSF
cultures
- Electrolytes, BUN, creatinine, and glucose
- Arterial blood gas and serum lactate
-
Older patient with hypertension
- Urinalysis, electrolytes, BUN, creatinine,
glucose
- Early onset – may reveal heart enlargement,
pulmonary edema and other signs of congestive
heart failure
- Late onset – cardiomegaly, arch indentation
in the area of coarctation, rib notching
-
Echocardiography – delineates
intracardiac anatomy and allows for the assessment
of associated significant intracardiac anomalies,
also the suprasternal notch view allows evaluation
of the aortic arch to assess the transverse aortic
arch, the isthmus and the severity of coarctation.
Doppler echocardiography allows measurement of
the gradient at the area of coarctation.
-
CT scan and MRI – useful
in the older patient with more limited echocardiographic
views or the post-operative patient for assessment
of residual arch obstruction or arch hypoplasia.
Other Tests:
- Electrocardiograms
- Early onset in the neonate or infant may reveal
right ventricular hypertrophy rather than left
ventricular hypertrophy. May also reveal evidence
of ischemia.
- Late onset usually reveals left ventricular hypertrophy
and may show signs of left ventricular ischemia
or strain.
Procedures:
- Allows evaluation of the severity of coarctation
and arch anatomy including hypoplasia of the
transverse arch or isthmus.
- Helps to confirm the diagnosis when the echocardiogram
is not completely clear.
- Allows evaluation of intracardiac anatomy
and the contribution of associated lesions
to the overall hemodynamic disturbance.
- May allow intervention in the form of balloon
aortoplasty in native or recurrent coarctation.
Histological Findings: Coarctation
of the aorta results from marked ridge-like thickening
of the media of the aortic wall opposite the insertion
of the patent ductus arteriosus or ligamentum arteriosum.
The intima in this area may initially be thin but may
thicken over time. This ridge or shelf becomes obstructive
when the patent ductus involutes and when ductal tissue
in the wall of the aorta involutes.
- Supportive care
- Treatment of congestive heart failure with diuretics
and inotropic drugs
- Infusion of prostaglandin E1 (.05 to .15 mcg/kg/min)
to open the ductus arteriosus
- Ventilatory assistance in cases of markedly increased
work of breathing
- Foley catheter insertion to follow renal perfusion
and urine output
- Arterial blood gases to follow acidosis
- Umbilical artery catheter may be placed in the
neonate to assess the response to prostaglandin
infusion with regard to improving lower body blood
flow
- Stabilization makes the patient a better candidate
for surgical intervention
-
Late presentation
- Treatment of hypertension
- Evaluation of associated abnormalities such as
aortic stenosis, subaortic stenosis or mitral valve
disease
- Evaluate adequacy of collaterals in order to
assess the safety of operative intervention
- Preoperative evaluation of intracranial vessels
to exclude aneurysms.
Surgical Care: Surgical correction
of coarctation of the aorta may be performed in isolation
or as part of the repair of associated complex anomalies.
For isolated repair, three techniques have evolved
over time including end-to-end anastomosis, patch aortoplasty
and left subclavian flap aortoplasty. These techniques
may occasionally be combined or modified to fit the
individual patient’s complex anatomy. For
instance, a reverse left subclavian flap aortoplasty
may be utilized in which the left subclavian artery
is turned as a patch back towards the left carotid
artery to enlarge an area of transverse arch hypoplasia. In
addition, a so-called “extended” end-to-end
repair may be utilized in which the segment of descending
aorta is beveled and brought up to the underside of
the transverse arch to enlarge areas of transverse
arch hypoplasia. The exact technique employed
varies depending on patient’s age at presentation,
size, associated abnormalities and arch anatomy.
Early presentation coarctation: The neonate or infant
who presents in extremis with congestive heart failure
requires urgent resuscitation. In infants less
than two weeks of age in whom the patent ductus arteriosus
may have only recently closed, a trial of prostaglandin
E1 infusion is indicated to try to reopen the patent
ductus. Restoring lower body perfusion by opening
the ductus allows improvement in urine output, clearing
of metabolic acidosis and makes the patient a more
stable and better candidate for eventual surgical repair.
The availability of prostaglandin E1 has greatly lowered
the risk of morbidity and mortality associated with
coarctation repair in the neonatal period.
After a period of stabilization and assessment of
associated malformations if present, the patient may
undergo elective operation for repair of coarctation. In
a review of 1,337 patients undergoing repair of coarctation
in infancy: subclavian flap aortoplasty was performed
in 763 (57 percent); resection in end-to-end anastomosis
was used in 406 patients (30 percent); and patch aortoplasty
in 133 (9.9 percent). Twenty additional patients underwent
placement of an interposition graft or bypass graft. Mortality
risk in this series was highest in neonates operated
on during the first week of life while there were only
eight deaths among 279 infants operated on between
three months and one year of age. Operative mortality
was also higher for smaller infants, particularly those
less than three kg, and when there were associated
cardiac anomalies. The presence of a ventricular
septal defect either with or without minor associated
anomalies increased the risk of death from 0.9 percent
when no anomalies were present to 6.8 percent when
a VSD was present. Complex associated anomalies
such as single ventricle or transposition of the great
arteries greatly increased mortality to 16.6 percent.
Similarly, neonates who required an operative procedure
prior to coarctation repair had an operative mortality
of 45 percent. Urgent operation may need to be undertaken
if the patent ductus cannot be opened and the patient
continues to have evidence of poor urine output and
acidosis.
In the presence of a hemodynamically significant VSD,
placement of a pulmonary artery band at the time of
left thoracotomy for coarctation repair may be considered. In
the case of severe transverse arch hypoplasia resulting
in significant residual obstruction following coarctation
repair, an ascending to descending aortic conduit may
be placed. This is generally a less favorable
approach as it may obligate the patient to subsequent
surgeries for conduit replacement. In some centers,
associated defects may be addressed at the time of
coarctation repair by proceeding with median sternotomy
and VSD closure after completion of the coarctation
repair.
Late presentation coarctation: Repair of coarctation
in the asymptomatic child or adolescent is usually
undertaken on an elective basis after assessment of
associated anomalies and appropriate pre-operative
evaluation. Timing of intervention in the otherwise
asymptomatic patient has been debated over the years.
Rationale for delaying surgery until 3 to 5 years of
age has been based on the size of the aorta in childhood
relative to the anticipated adult size. Since significant
obstruction occurs when the diameter of the aorta is
reduced by 50 percent or more, delaying surgery until
3 to 5 years of age allows the aorta to be greater
than half the anticipated adult size at the time of
operation; thus, theoretically reducing the risk of
significant residual obstruction in the event that
the surgical repair site does not grow over time. Improvements
in operative technique have led most cardiologists
to recommend surgery at the time of diagnosis, especially
if the patient is hypertensive. In patients with only
mild obstructive, especially those diagnosed in the
first year of life, surgery may be safely delayed and
the patient followed for worsening obstruction or the
development of hypertension prior to recommending surgery.
Pseudocoarctation of the aorta refers to abnormal
tortuousity of the aorta that does not result in significant
obstruction, does not result in hypertension and is
also noted for the lack of development of collateral
vessels. This abnormality does not require surgical
intervention.
Surgical technique: Surgical repair of coarctation
of the aorta is accomplished in children and adolescents
with generally good results and very low mortality.
Of 824 patients undergoing coarctation repair in childhood,
431 (52 percent) underwent end-to-end anastomosis while
patch aortoplasty was performed in 214 patients (26
percent) and only 109 patients (13 percent) underwent
subclavian flap aortoplasty. There were only six deaths
out of 824 patients for a total mortality of 0.73 percent.
There has been a trend towards less frequent use of
patch aortoplasty because of concerns regarding the
development of aortic aneurysm at the site of repair.
Recurrent coarctation: In the current era, recurrent
coarctation of the aorta is usually treated by balloon
aortoplasty. Re-operation is occasionally undertaken,
especially in the presence of residual obstruction
in the transverse arch in the setting of unusual arch
anatomy. Balloon aortoplasty for recurrent coarctation
has been shown to be highly effective in relieving
residual obstruction both acutely and in the intermediate
term. More recently, endovascular stents have been
placed for treatment of recurrent coarctation in older
children and adults with good success, though long-term
follow-up is lacking.
Balloon aortoplasty of native coarctation: Initial
experience with balloon aortoplasty for native coarctation
was significantly less successful than surgical intervention.
This led some cardiologists to reserve balloon aortoplasty
exclusively for recurrent coarctation. With improvements
in balloon technology allowing the use of smaller balloons
with less risk of trauma to the femoral vessels, some
centers preferentially perform balloon dilation of
native coarctation of the aorta as initial therapy.
Surgery is reserved for those patients who have a poor
response to balloon dilation or who have recurrent
coarctation after initial balloon dilation. Long-term
results with this technique are lacking and surgical
intervention remains the gold standard by which the
approach of initial balloon dilation must be judged.
Consultations Regarding Non-Cardiac Problems:
In the infant presenting early with congestive heart
failure, management in the ICU for stabilization may
be required prior to operative intervention. Premature
infants may require the assistance of a neonatologist
in the management of associated diseases related to
prematurity such as hyaline membrane disease. Genetics
consultation may be indicated if Turner Syndrome or
other genetic conditions are suspected. Acute
renal failure may occur pre- or post-operatively and
require the assistance of a nephrologist, who may also
assist with management of hypertension.
Older patients may be initially referred to other
consultants prior to the diagnosis of coarctation. For
instance, referral to a hypertension clinic may lead
to the diagnosis of coarctation of the aorta by the
nephrologist. Patients being evaluated for suspected
genetic syndromes may be referred to the cardiologist
for evaluation because of previously undiagnosed coarctation.
Complications of coarctation of the aorta, such as
intracranial hemorrhage or endocarditis may require
the consultation of a neurosurgeon or infectious disease
specialist respectively.
Diet: Persistent hypertension has
been shown to increase the incidence of coronary artery
disease. Patients who have undergone repair of
coarctation of the aorta must be followed for hypertension
and a healthy diet low in fat should be recommended.
Cholesterol should be measured and even pharmacologic
intervention should be undertaken as indicated with
a goal of total cholesterol less than 200 grams per
deciliter. Patients with persistent hypertension may
require varying degrees of salt restriction. Dietary
counseling and avoidance of obesity and smoking are
particularly important.
Activity: Patients with coarctation
who have not yet undergone surgical repair and are
hypertensive should have limitation of heavy isometric
exercises to a degree commensurate with their degree
of hypertension. In general, it is felt that
the duration of hypertension after coarctation repair
is related in part to the duration of hypertension
prior to diagnosis and repair of coarctation of the
aorta. Patients who undergo repair of coarctation
in infancy most often remain normotensive in the absence
of significant residual arch obstruction and require
no specific restrictions or limitations to activity. It
should be remembered that with growth, recurrent coarctation
may occur and that some patients may be normotensive
at rest but have significant upper extremity hypertension
provokable with exercise. Such patients, especially
those who wish to participate in competitive athletics,
should undergo exercise stress testing prior to clearance
for participation in competitive athletics.
Patients who undergo repair later in life and who
have had a significant period of pre-operative hypertension
are at particular risk to have sustained post-operative
hypertension that may be permanent. Such patients
should be restricted from heavy isometric exercise
and other activities restricted commensurate with their
degree of hypertension and blood pressure control.
Exercise testing to assess blood pressure response
to exercise is particularly useful in this group of
patients as a means of delineating reasonable exercise
restrictions.
Medical Treatment: Congestive heart
failure: The occasional infant may present with significant
ventricular dysfunction, which very often improves
or resolves after repair of coarctation and relief
of obstruction. Occasionally, the patient will have
sustained significant injury to the left ventricle
resulting in a chronic cardiomyopathy. Such patients
are best treated with standard management, which might
include digitalis, diuretics and afterload reduction.
A careful evaluation should also be made to exclude
residual arch obstruction or heart failure due to other
associated anomalies such as aortic valve stenosis
or insufficiency, subaortic stenosis, mitral stenosis
or regurgitation or coronary anomalies.
Hypertension: Antihypertensive therapy is very commonly
needed both in the immediate post-op period and on
a chronic basis. Some centers place patients on antihypertensive
therapy pre-operatively, usually with beta-blockers,
in the hope of reducing the severity of post-operative
hypertension after repair of coarctation.
Acute post-operative hypertension may be treated with
standard therapy such as afterload reducing agents,
beta-blockers, or angiotensin converting enzyme inhibitors.
Sodium nitroprusside may be used, but is frequently
inadequate in the early post-operative period to control
hypertension, even at high doses. The goal of antihypertensive
therapy should be to keep the systolic blood pressure
less than the 95th percentile for age if possible.
Beta-blocker therapy is best instituted with an Esmolol
infusion in the early post-operative period with the
infusion titrated to effect. Patients who have
a satisfactory response may be converted to oral beta-blocker
therapy with other drugs such as Atenolol if hypertension
persists. Angiotensin converting enzyme inhibitors
may be used for chronic therapy either alone or in
combination with diuretics and/or beta-blockers.
Early Post-Operative Recovery: Post-operative
recovery should focus on control of blood pressure,
slow advancement of the diet, manipulation of antihypertensive
medications, progressive ambulation and a focus on
pulmonary therapy to improve left lung atelectasis,
which is so common after left thoracotomy.
Outpatient Care: Early outpatient
follow-up care should focus on wound healing, resolution
of lung atelectasis and adjustment of antihypertensive
medications. Many patients may be weaned off
antihypertensive therapy over months or years following
repair of coarctation. Other patients may require some
form of on-going antihypertensive therapy. A post-operative
assessment of blood pressure response to exercise should
be employed prior to complete discontinuation of antihypertensive
therapy. A search for late complications of coarctation
repair including recurrent coarctation and aneurysm
formation is also indicated.
Prevention: While the occurrence
of coarctation of the aorta cannot be prevented per
se, early detection can be accomplished by fetal echocardiography.
The diagnosis of coarctation of the aorta can be difficult
by fetal echocardiography but might be considered when
there is unexplained enlargement of the fetal right
ventricle, difficulty in identifying the true aortic
arch, identifying an unusual aortic arch contour or
when associated anomalies are identified that might
be associated with coarctation of the aorta such as
other forms of left heart obstruction. A fetal echocardiogram
is indicated in every woman who has delivered a previous
child with congenital heart disease, especially left
heart obstructive lesions.
Postnatally, early detection of coarctation of the
aorta is important to avoid prolonged hypertension
or other complications. Careful evaluation of the lower
extremity pulses in the newborn nursery and at subsequent
well child check-ups is imperative.
Complications: Coarctation of the
aorta is a life-long disease with complications that
may not be evident until many years following initial
apparent successful repair.
Recurrent coarctation: Recurrence of coarctation is
associated with smaller patient size and younger age
at operation, and in the presence of associated transverse
arch or isthmic hypoplasia. Ductal tissue in
the wall of the aorta may involute and contribute to
recurrent coarctation as does scarring at the repair
site. Some surgeons feel that utilizing interrupted
sutures in the anterior portion of the anastomotic
suture line improves aortic growth and reduces the
risk of re-coarctation. Sometimes the surgical
repair site is unobstructed but obstruction develops
at the transverse arch or isthmus related to failure
of these areas to grow proportionally to the rest of
the arch. Such obstruction may not be detected for
many years after initial repair.
Some patients who have undergone initial repair with
a left subclavian flap aortoplasty may have a tortuousity
to the repair site which does not result in obstruction
until they go through the period of rapid growth in
adolescence.
Aortic aneurysm: Aneurysm of the aorta can occur in
unrepaired coarctation of the aorta and has been described
in patients with Turner Syndrome and coarctation of
the aorta. In addition, endocarditis can result
in aortic arch aneurysm (mycotic aneurysm) usually
distal to the site of obstruction. Patch repair of
coarctation of the aorta has appeared to result in
an increased incidence of aortic aneurysm, particularly
if the shelf of coarctation tissue is excised. The
aneurysm usually occurs opposite the site of the patch
and can be entirely asymptomatic. Hoarseness,
due to stretch of the recurrent laryngeal nerve associated
with aortic aneurysm, has been described. Chest X-ray
may detect the aortic arch aneurysm but magnetic resonance
imaging is more useful in delineating the size and
extent of the aneurysm.
Persistent hypertension: Hypertension may persist
even after successful repair of coarctation of the
aorta and is, in general, related to the duration and
severity of pre-operative hypertension. This
is probably related to alterations in the renin angiotensin
system and baroreceptors. As with other forms of uncontrolled
hypertension, patients may be at risk for premature
coronary artery disease, ventricular dysfunction and
rupture of cerebral aneurysms.
Cerebral aneurysm: Berry aneurysms of the circle of
Willis or other vessels are thought to occur in as
many as 10 percent of patients with coarctation of
the aorta and may be multiple. Aneurysm size
tends to increase with age as does the likelihood of
rupture. Uncontrolled hypertension promotes growth
of the aneurysms and increases the risk of rupture.
Most patients are asymptomatic until rupture occurs,
though some aneurysms may leak prior to rupture resulting
in warning symptoms of headache, photophobia, weakness
or other symptoms. Rupture of a cerebral aneurysm
is associated with high mortality and should prompt
repair of both the aneurysm and the coarctation.
Paralysis: Though rare, paralysis can occur due to
spinal cord ischemia resulting from compromised blood
supply to the anterior spinal artery. This risk is
increased when there are reduced arterial collaterals,
with prolonged aortic cross-clamp time, with intraoperative
sacrifice of intercostal arteries, as well as other
factors. Paralysis is uncommon in the presence
of a well developed collateral supply and this emphasizes
the importance of assessing collateral arterial flow
prior to surgical intervention. Methods to prevent
cord ischemia include hypothermia, utilization of cardiopulmonary
bypass or the insertion of a bypass graft with partial
aortic clamping.
Cardiomyopathy: Cardiomyopathy is most often present
in the infant who presents with critical coarctation,
especially if there are additional levels of left heart
obstruction such as aortic stenosis or subaortic stenosis.
Some patients may have changes of endocardial fibroelastosis
that result in a chronic dilated cardiomyopathy requiring
medical management or in rare cases cardiac transplantation. Hypertrophic
cardiomyopathic changes may also occur, which may predispose
the patient to subendocardial ischemia, arrhythmias
or congestive heart failure related to diastolic dysfunction.
Chylothorax: An extensive dissection may result in
disruption of the thoracic duct leading to chylothorax
which is recognized when feedings are instituted post-operatively.
Persistent chylous pleural effusions may necessitate
chronic chest tube drainage. Some patients respond
to therapy with fat restriction or total parental nutrition.
Refractory cases may require pleurodesis or thoracic
duct ligation.
Post-coartectomy syndrome: Restoring pulsatile blood
flow to the mesenteric arteries may result in a mesenteric
arteritis in which the arteries become distended and
may rupture. Reflex arteriolar vasoconstriction occurs
as part of autoregulation of blood flow and can result
in ischemia. Clinical manifestations may range from
mild abdominal discomfort to acute abdomen with severe
abdominal distention, vomiting, ileus and progression
to intestinal wall hemorrhage or perforation. The development
of this syndrome is thought to be related to early
refeeding after coarctation repair. Thus, feedings
are normally delayed for 48 hours after surgery and
nasogastric tube decompression is continued during
that time until feedings are slowly begun and advanced
as tolerated. Severe cases may require exploratory
laparotomy for treatment of bowel necrosis or perforation.
Prognosis: Coarctation of the aorta
is a life-long disease with a prognosis that is guarded. Relief
of obstruction, control of hypertension, follow-up
for recurrent obstruction and follow-up of associated
anomalies is imperative. SBE prophylaxis should be
continued indefinitely even in the absence of associated
abnormalities.
Patients without residual obstruction who are normotensive
both at rest and with exercise should lead normally
active lives without restriction. Most such patients
should be able to obtain health insurance and life
insurance. Patients with persistent hypertension, untreated
residual obstruction or other complications have a
variable prognosis related to the severity of these
problems.
Education: Patients, in addition
to their families, should be educated that coarctation
of the aorta requires life-long follow-up to detect
recurrent coarctation or late complications. They should
be educated about a healthy lifestyle to include the
avoidance of smoking and obesity, the value of aerobic
exercise, the appropriate control of blood pressure
and reduction of other factors that influence cardiovascular
disease.
Special concerns: After successful
repair of coarctation of the aorta, pregnancy should
be well tolerated. Prenatal care should include
careful monitoring of blood pressure as hypervolemia
of pregnancy may contribute to worsening hypertension,
especially in patients with some degree of residual
obstruction or pre-existing hypertension. The presence
of other associated lesions such as aortic valve disease
may further complicate obstetrical management. There
are anecdotal cases of aortic rupture during pregnancy.
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A
Child Life Specialist: More than Bubbles,
Blocks and Barbies
Mandy Staggs, CCLS; Child Life
and Education Department; Arkansas Children's Hospital
Throughout the five years I have been a Certified
Child Life Specialist in the Heart Center at Arkansas
Children's Hospital (ACH), I cannot begin to count
the number of times I have been asked the question, “What
is a Child Life Specialist?” The answer
to this question can take many forms based on the time
I have to explain, but to put it simply, “a Child
Life Specialist is a part of the team that helps a
child and family cope with being in the hospital, thereby
reducing anxiety associated with the hospital stay.”
Helping a child or family cope with being in the hospital
begins when a new patient comes into the hospital.
Explaining the unfamiliar and allowing the patient/family
to explore the hospital environment is key to promote
positive coping to the hospitalization. This
is achieved through explanations of surgical procedures
and medical equipment in language the patient/family
can understand. This allows for questions and misconceptions
to be addressed. Also, medical play can be introduced
to the patient. An example of medical play is a play
session in which real medical equipment can be used
to perform procedures on dolls. Medical play can be
used to explain procedures as well as the medical equipment
present after surgery. This can assist with reducing
anxiety and allow the patient to gain understanding
of the hospital experience.
Playrooms are another tool that can assist in coping
with a hospital stay. There are many playrooms located
throughout ACH, including specialized playrooms on
units. The Heart Center has its own playroom specifically
for the cardiac patients. There are many toys, activities,
books, movies and video games available to accommodate
all ages from newborns to teens.
Another tool that assists with coping is the TAILS
(Therapeutic Animal Interventions Lift Spirits) program.
TAILS is animal-assisted therapy, in which certified
therapy dogs visit patients in their rooms, providing
a therapeutic interaction to help reduce pain or anxiety
associated with diagnosis or hospitalization.
There is also scrapbooking time each week for families
to make memories to take home. The family provides
the scrapbook, but the pages and other supplies are
supplied for the families who wish to participate.
There is also the Hospital School Program where teachers
can assist with any schooling needs. This helps the
patients stay caught up with any school work that may
be missed because of the hospitalization.
All of the various aspects of the Child Life role
will be available during a hospitalization in the Heart
Center. Beginning in pre-op clinic, I will provide
teaching for surgery by explaining the various medical
equipment the patient and family will encounter, and
provide a tour of the unit. I am available to assist
with distraction for medical procedures such as IV
starts, blood draws, vital signs, etc. In addition,
toys, activities, emotional support, sibling support
and play opportunities will be provided. I will
continue to follow the patient and family throughout
the hospital stay in order to promote a positive hospital
experience.
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Congenital
Heart Defects Awareness Day
Alysanne Crimes; Mom to ACH patient,
Brendan, 13, complete congenital heart block/pacemaker,
repaired ASD, and Lauren, 18
Congenital Heart Defects (CHD) Awareness Day began
in November 1999. Jeanne Imperati, a member of The
Congenital Heart Information Network (TCHIN), encouraged
members of the online support groups, visitors to the
site and interested health professionals to write to
their state governors, requesting that February 14,
2000 be proclaimed as A Day for Hearts: Congenital
Heart Defect Awareness Day™. Within several weeks
of her initial announcement, Mrs. Imperati and members
of our online community received proclamations from
forty-four states! I am proud to say that Arkansas
was one of these states and proclamations have been
approved every year since. In 2006, Congenital
Heart Defects Awareness Day was expanded to a full
week and renamed Congenital Heart Defects Awareness
Week. It was celebrated from February 7-14, 2006.
The purpose of CHD Awareness Week is stated best in
the proclamation: to encourage all citizens to increase
awareness, education and services for CHDs, which each
year affect thousands of babies. Raising public awareness
about CHD will help lift the barrier of ignorance,
helping both the families and individuals who currently
are affected by CHD, and those whose lives may be affected
in the future. TCHIN members have always been concerned
about the number of children who go undiagnosed at
birth and the lack of newborn screening. Members
are also concerned that even though CHD is the most
frequently occurring birth defect and leading cause
of birth defect deaths worldwide, a disproportionately
small amount of funding is available for CHD research
and support.
The first CHD Awareness Day in Arkansas was in 2000
and it was organized on extremely short notice. The
Governor's Office notified me that our proclamation
had been approved. The ceremony would be held in two
days and a list of attendees was needed the following
day. I scrambled to assemble a group together
and participants at our first ceremony included four “heart
kids” and their families. We were especially
proud that KATV, Channel 7, here in Little Rock agreed
to do a short piece. Donny McGuire, our adult
CHD patient was interviewed along with Sawyer Evans
and mother, Kerri, and also Kim Wilkins, mother of
Brittany Wilkins. They discussed what it is like
living with CHD and Kim Wilkins emphasized the importance
of organ donation.
The following year saw participation from the Cardiology
Department of Arkansas Children's Hospital. Connie
Jones, RNP, Dr. Chris Erickson, and Kathy Ainley, RNP
attended, along with Dr. Mary Aitken from general pediatrics. The
American Heart Association was also represented. We
were also pleased to welcome more families and children
affected by congenital heart disease.
By far, our best-attended event was in 2002, the same
year Dr. Drummond-Webb became the chief of cardiovascular
surgery at ACH. I sent out the invitation to
hospital employees and Dr. Drummond-Webb, I understand,
cleared the surgery schedule so that his operating
room staff could attend. We had the largest
group ever, including even more family members.
CHD Awareness Week was proclaimed this year on February
15 in the Governor's Reception Room at the State Capitol. I
was most pleased that ACH chief of cardiothoracic surgery,
Dr. Jaquiss was able to attend, along with Deeann Martin,
RNP, Dr. Michael Schmitz, anesthesiology and Mark Charette,
principal sales and clinical consultant from Medtronic.
The “heart kids” included Brendan Crymes,
Xavier Taylor and Lindsey Taylor and their families.
I wish to express my gratitude to the cardiology staff
at ACH for their support and encouragement over the
years for this project. For more information
on TCHIN or Congenital Heart Defects Awareness Week,
visit the Web site at www.tchin.org. It
is a great resource for parents as well as health care
professionals.
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Spotlight on Rosie
Webb
Pediatric and Congenital Cardiothoracic Surgery
What is your role at ACH and how long have
you worked here?
I am an instrument tech. My role is to count, check,
assemble and sterilize instruments to make sure everything
is ready and sterile for the cases. I have worked at
ACH for two and half months.
Why is your job rewarding?
Being part of the team, helping the children, praying
for their recovery and the staff in the cardiovascular
operating room (CVOR) unit make my job rewarding.
Also, knowing my co-workers feel I am an important
part of the team.
How did you become interested in pediatric
cardiology or cardiovascular surgery?
I worked at the Heart Hospital in cardiovascular surgery
when I came to ACH for my interview. I say that it
was not just a job. It is about relationships – a
loving, caring, helpful team. It is important to have
co-workers like everyone in the CVOR; this makes it
a joyous place to work.
What do you want people to know about the Heart
Center at Arkansas Children's Hospital?
That this is the best place to work. The people are
so wonderful, not just in the CVOR, but also the cardiovascular
intensive care unit and everyone that makes up the
team. When you have a wonderful team you have a wonderful
place to work. I have worked with instruments for 30
years, and this place is the greatest
What do you enjoy most about working with
children?
I have always been concerned about children, and have
prayed for their safety. I got my answer. I am here
and I enjoy being here. I love children, and will do
anything to help them. My heart goes out to them.
What has been your most memorable moment working
in the Heart Center at Arkansas Children's Hospital?
The first impression… the way everyone received
me and appreciated me as part of the team. I couldn’t
believe the way they welcomed me as a part of the team.
I know the welcome was a true welcome, and I am glad
I came.
What is your greatest professional achievement?
To be the best interior decorator I can be!
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Spotlight on
Becky Looney
Heart Station
What is your role at ACH and how long have
you worked here?
I’m a registered diagnostic cardiac sonographer,
or more simply, an echo tech. The first time,
I worked here for 16 years (1980-1996). The second
time, five years (2000-present)
Why is your job rewarding?
I receive a great deal of satisfaction knowing that
I have a small part in the care of children with
heart disease as well as assisting their families.
This position has never been a “job” to
me; it’s been more of a calling. I’ve
learned so many things and am so fortunate to have
this opportunity. It’s always been about how
I can use the skill God has given me in assisting
the physicians in delivering better care to the patients
and showing compassion to our families.
How did you become interested in pediatric
cardiology or cardiovascular surgery? As
a college student, I worked part time at UAMS in
the Department of Pediatrics as a secretary. I helped
with Cardiology Clinic appointments, copied charts
as the Pediatric Cardiology Clinic moved from UAMS
to ACH and then I began to transcribe clinic dictations.
I learned about the clinical histories of many of
the patients. I had a true desire to learn and do
more for these patients and their families. Dr.
J. B. Norton gave me the opportunity to do just that.
I was trained in EKG, stress testing, holter application
and echocardiography by Drs. Norton, Dungan, Readinger
and Kiel in a small room across the hall from the
cafeteria that was affectionately named “The
Heart Station”. I’m thankful they
took a chance with me.
What do you want people to know about the Heart
Center at Arkansas Children's Hospital? The
Heart Center is a team effort to care for sick children
and their families. It takes all of us,
working diligently, as “experts” in
our fields to provide a positive outcome for our
patients and their families. When the outcome is
positive, we rejoice with the family. When the outcome
is heart breaking, we grieve with the family. We
work as team but our work never stops at the bedside.
What do you enjoy most about working with
children?
I love their smiles, laughs, hugs and most of all,
when they come back as young adults and say “thank
you for what you did for me and for helping my family
through a hard time.” I think God smiles
when that happens and what better reward can you receive?
What has been your most memorable moment working
in the Heart Center at Arkansas Children's Hospital?
There are so many that it’s impossible to name
just one. I’ve had the opportunity to work with
and for some of the most intelligent, caring and devoted
people who have kept their focus on the patients. Thank
you for teaching me and tolerating my questions. Please
be patient, I still have so much to learn.
What is your greatest professional achievement?
Obtaining my credentials, Becky Looney, RDCS.
Staff Testimonial about Becky Looney
“I wanted to thank you for featuring Becky Looney in the Heart Center
newsletter. As so many of us know, she has been the backbone of the non-diagnostic
testing in cardiology since 1981!! She started the Heart Station and was the
only Heart Station employee when it began with Dr. Norton's help in 1981. Then
a few years later, she got the help of another tech and then in 1986, I came
along as the Heart Station secretary. We have been together ever
since. Without her, the non-diagnostic testing would not be where
it is today. Her care and love of the patients and there families is endless
as we can all attest. She keeps scrapbooks and scrapbooks full
of cards, graduation announcement, wedding announcements and yes, even birth
announcements from the patients she has seen throughout the years. This
itself should speak volumes about the care, love and hope that she has given
the kids with congenital heart disease throughout the years.”
--Lori Heil, registered diagnostic cardiac sonographer
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