++
The complaint of chest pain in children is common. With the public
media highlighting cardiac disease in the adult population and publishing tragic
stories of young athletes dying suddenly on the field, it is not
surprising that parents assume that any chest discomfort may involve
the heart. Most chest pain is benign. In multiple studies in various
settings, cardiovascular disorders have accounted for fewer than
5% of pediatric patients presenting with chest pain.6-10 Chest
pain in children is most common in early adolescence; younger patients
with chest pain tend to have a higher incidence of organic disease.
In one study, patients under 12 were twice as likely as older children
to have a cardiorespiratory cause for their complaint whereas older
adolescents were 2.5 times more likely than younger children to
have a psychogenic reason for the complaint.7 There is
an increased incidence of chest pain in overweight children.9
++
There are many structures that can cause pain in the thorax.
The musculoskeletal system is often implicated as the origin of
pain. However, the respiratory system, cardiovascular system, gastrointestinal
system, nervous system, and integument may be the culprit.
+++
Noncardiac Causes
of Chest Pain
++
Table 486-1 lists some common noncardiac causes
of pediatric chest pain.
++
++
Patients presenting with idiopathic chest pain typically have
a history of episodes of pain over the previous weeks to months.
The pain is usually sharp, but brief. It may or may not increase
with deep inspiration. There are usually no other symptoms associated
with the episodes. The patients’ activities are usually
not interrupted. The physical examination is normal, and the pain
cannot be reproduced on the examination. Episodes can be recurrent,
but do not become chronic.7
++
Psychogenic chest pain often initially presents after an identifiable stressful
event.11 The pain is usually nebulous and associated with
other symptoms such as abdominal pain and headaches. Symptoms of
anxiety may accompany the complaint,8 and in one report,
parental anxiety was out of proportion to that of the patient.6 The typical age
of onset is adolescence, and females tend to outnumber males.
++
Costochondritis is pain and tenderness at the costochondral junction
of the rib and the sternum. There is often a history of strain associated
with illness and coughing or activity just prior to the onset of
complaint. The pain is usually sharp in nature and can radiate.
Activity tends to increase pain, as does deep breathing. Typically,
the pain is unilateral and in the midsternal junctions. It is reproducible
with palpation. Like other overuse injuries, recurrence is common.
++
The precordial catch is also known as Texidor twinge, reported
in 1955 and recently reviewed.12,13 It is a very specific
condition consisting of a severe sharp, stabbing, or needlelike
pain at a very localized point on the chest. Episodes are brief,
exacerbated by a deep breath, and occur during rest, but not during
sleep. Resolution of an episode is rapid and complete. The cause
of the pain is unknown, although the pleurae have been suggested
as the source.
++
The distal 3 ribs are in fibrous continuity, but do not attach
to the sternum directly. In slipping rib syndrome, one of these
ribs slips over the other, creating pain. This is thought to occur
as a result of trauma. The patient complains of a popping sound
and pain, both of which can be reproduced by hooking the rib manually
and pulling forward.14
++
Because the parietal pleura is richly innervated, pain arises
when it is inflamed, irritated or injured. Acute severe chest pain
accompanies spontaneous pneumothorax. The pain is sudden in onset
and, depending on the amount of air in the pleural cavity and degree
of lung collapse, is accompanied by dyspnea. Tension pneumothorax
develops when air enters the pleural cavity during inspiration,
but cannot exit from the site of lung rupture during expiration.
The high pressure in the pleura and mediastinum may interfere with
venous return to the heart, and it is life-threatening because cardiac
output is impaired; removal of air is required immediately to relieve intrapleural
pressure. Acute chest pain, characteristically occurring during
inspiration, may be the result of pleuritis, result from viral infection, or
be associated with bacterial pneumonia with pleural involvement;
these individuals usually have fever and varying degrees of dyspnea.
++
Chronic chest pain may arise from pleural irritation resulting
from chronic infection, such as tuberculosis. Pleuritis is also
present in rheumatologic disorders, occurring in about 50% of
patients with systemic lupus erythematosus. Chest pain is a frequent
complaint in patients with asthma. Exercise-induced asthma is an
important cause of chest pain in children. It is associated with
the bronchospasm and manifests as a feeling of tightness of the
chest, with acute substernal pain. It may present during exertion
but often develops a few minutes after cessation of exercise and
gradually improves within about 30 minutes. The association of the
pain with activity or exercise often raises concern about a cardiac cause.15 Danduran
and colleagues found that in patients evaluated in a cardiology
clinic for chest pain, 26% had evidence of reactive airway disease
with abnormal resting pulmonary function tests.9 However,
two thirds of those patients had never been diagnosed with reactive
airway disease.
+++
Cardiac Causes
of Chest Pain
++
Ischemic chest pain is associated with congenital coronary anomalies,
vasospasm, or left-sided outflow obstruction. Ischemia can be also
worsened by drugs such as bronchodilators used for asthma, because
they also increase heart rate, myocardial oxygen demands, and decrease
aortic diastolic pressure; thus, it may not be appropriate to ascribe
all feelings of chest discomfort or pain to bronchoconstriction
in patients being treated for reactive airways disease, especially those
receiving high doses of medication. Patients with tachycardia also
frequently complain of pain during an episode. Aortic dissection,
often associated with connective tissue disorders, causes acute,
chest pain in the upper chest and neck for the ascending aorta and
in the back for the descending aorta. Inflammation of the pericardium
often is also associated with anterior chest pain.
+++
Coronary Artery
Anomalies
++
Congenital coronary artery anomalies are relatively rare, but
may be fatal. Those involving anomalous origin of a coronary artery
from the pulmonary artery usually present early in life when pulmonary
vascular resistance falls, decreases coronary perfusion pressure,
and causes myocardial ischemia (so-called myocardial steal). Infants
present with fussiness and diaphoresis associated with feeding,
but older patients may have exertional chest pain, syncope, or simply
a continuous murmur. If a coronary artery arises anomalously from
the wrong (ie, ectopic) sinus of Valsalva, it may cause myocardial
ischemia or even sudden death.9 Thus, a careful history
is important, and a thorough cardiovascular evaluation is necessary
when chest pain occurs during or immediately after exercise. The
electrocardiogram and cardiac biomarkers such as troponin may be
normal between episodes. Although congenital coronary anomalies
can be detected by echocardiography, this requires a meticulous
examination by sonographers familiar with coronary anomalies.
++
Vasospasm has been the working diagnosis in several reports where
adolescents presented electrocardiograph and enzyme changes consistent with
myocardial infarction.6 The patients typically have crushing
and unrelenting chest pain with cardiac gallops and murmurs of mitral
regurgitation. Often there are no predisposing factors for coronary
artery disease. On catheterization, the coronaries are patent. It
is essential to evaluate for sympathomimetic drug abuse, especially
cocaine, which can cause myocardial ischemia from coronary vasospasm
and increased myocardial oxygen demand.16
++
Kawasaki disease (see Chapter 488) is a
diffuse vasculitis involving the coronary arteries. It may result in
giant aneurysm formation with subsequent risk of thrombosis or rupture.17 Therefore,
a history of Kawasaki disease or a prolonged febrile illness with
skin rash should raise suspicion of a possible cardiac origin in
patients presenting with chest pain.
+++
Left Ventricular
Outflow Obstruction
++
In left ventricular outflow obstruction, there may be insufficient
coronary blood flow as a result of a fixed obstruction at the level
of the aortic valve or supravalvular area. With hypertrophic cardiomyopathy
there is a mixture of a fixed component and a dynamic component
in the subaortic area. The dynamic component worsens with decreased
LV filling and increased contractility. Findings on physical examination
include a hyperdynamic apical impulse, a harsh systolic ejection
murmur (often with radiation to the suprasternal notch), and in
some an apical murmur of mitral regurgitation.
++
(See Chapter 485.) Some patients report
chest pain during episodes of tachycardia. The cause of the pain
is unclear and it may be a younger child’s way of describing
palpitations or dyspnea. Episodes generally start and stop suddenly.
They may be related to activity or occur at rest. Other symptoms
such as dizziness or shortness of breath may accompany the episode.
If the patient has returned to normal rhythm, the physical examination
will likely be normal. The diagnosis is most often established by
ambulatory electrocardiographic monitoring.
++
Aortic dissection in pediatric patients is usually related to
trauma or connective tissue disease. Patients with connective tissue
disease such as Marfan, Ehlers-Danlos, and Turner syndromes and
with a bicuspid aortic valve are at increased risk due to abnormal
connective tissue in the media of large arteries. As the aorta enlarges,
wall tension increases and may result in dissection or rupture.
Patients describe severe, tearing chest pain, often in combination
with respiratory distress, diminished peripheral pulses, and shock. Thus,
any chest pain in patients with the above conditions must be taken
very seriously and regarded as a potential medical emergency.
+++
Pericarditis
and Myocarditis
++
(See Chapters 489, 491.) Inflammation of
the pericardium and adjacent myocardium typically causes anterior
chest pain. Pericarditis is often associated with a viral illness,
trauma, or uremia. The pain may be relieved by sitting upright and
leaning forward. The patient is usually febrile, uncomfortable,
and even toxic appearing. There may be a friction rub unless there
is a large effusion. With a large effusion or diffuse myocarditis,
the cardiac sounds are distant or muffled. Respiratory distress,
hepatic enlargement, and pulsus paradoxus indicate cardiac tamponade.
The diagnosis is usually made by echocardiography. Pericardiocentesis
may be life-saving in cardiac tamponade.
+++
Diagnosis and
Treatment
++
Most pediatric chest pain is benign and the etiology can often
be determined with a complete history and physical examination.
Repeated studies have found little utility in extensive testing
in the absence of an abnormality on the basic evaluation. In rare
but potentially life-threatening conditions, there are almost always
abnormalities on initial history and physical examination that point
toward the diagnosis. The challenge for the physician is to provide
reassurance to anxious patients and parents that most pediatric
chest pain is benign and self-limited, while at the same time keeping
an open mind to rare but life-threatening disorders. If needed,
any treatment is directed at the specific cause.
++
Syncope is the temporary, often brief, loss of consciousness
and postural tone caused by an abrupt decrease in cerebral blood
flow. Typically, there is a prodromal component, including dizziness, nausea,
diaphoresis, weakness, and loss of vision beginning in the periphery;
a rushing sound in the ears is common. The patient usually recovers without
intervention and without neurologic sequelae. Fortunately, most
syncope is benign, but 1% to 2% of patients have
significant underlying pathology.18-20 Syncope can occur
at any age, but the typical age of onset is adolescence.18,21
++
A simple faint, called neurocardiogenic syncope, is initiated
by pooling of the venous blood in the lower extremities by prolonged
standing or by abrupt assumption of an upright posture. This causes
a sudden loss of preload and stroke volume. A sympathetic response
is initiated, leading to tachycardia, vasoconstriction, and an increase in
contractility. C-fiber mechanoreceptor activation causes afferent
impulses to the medulla that, in turn, initiates a withdrawal of
sympathetic activity and an activation of the parasympathetic system.
This combination leads to venous and arterial vasodilatation, further
lowering preload and blood pressure. The parasympathetic activity,
carried by the vagus nerve to the heart, causes bradycardia, which
can be severe. The result of these reactions is the loss of adequate
cerebral blood flow, causing the loss of consciousness and postural
tone. Occasionally, myoclonic movements can occur, but tonic-clonic
seizures are rare. Once supine, venous return is restored, blood
pressure and heart rate normalize, and consciousness returns. Within
a few minutes, the patient feels well enough to stand and resume some
activity. If the patient tries to stand too soon, a recurrent loss
of consciousness is possible. Feeling tired is common, but true
postictal symptoms are absent. In addition to gravity-dependent
pooling of blood, injury, the fear of injury, pain, the sight of
blood, anger, or disgust are known initiators of syncope. Hair combing
is an unusual inciting event, and head turning, swallowing, micturition,
or defecation are uncommon triggers in children but have been described in
adults.
++
In children with syncope, the diagnosis is usually benign neurocardiogenic
syncope.18,19 However, the differential diagnosis
is large and there are many diseases, some life-threatening, that may
present as a syncopal episode (Table 486-2).
++
++
A syncopal event often produces considerable anxiety for the
patient, family, and perhaps the evaluating physician. Certainly,
some patients with syncope live in an environment with significant
psychological difficulties.22 This often leads
to extensive evaluations that yield no pathology.23,24 A
careful, complete history and physical along, with an electrocardiogram,
is generally all that is needed to determine the diagnosis. The
evaluation should be targeted at screening for more ominous etiologies
such as abnormal cardiac function, dysrhythmia, neurologic disease,
or psychiatric conditions. Specific information about the event from witnesses should
be sought in addition to the patient’s account. Clues from
the patient’s history that may indicate a more serious
cause of syncope are listed in Table 486-3.
Syncope with exercise warrants a thorough cardiovascular evaluation.
++
++
The physical examination should confirm normal vital signs as
well as evaluate orthostatic changes in heart rate and blood pressure. Body
habitus should be assessed. The mental status should be age appropriate.
Minor defensive injuries such as abrasions on the hands and arms
may be present, but there is usually no serious injury. The cardiac
examination should confirm the absence of increased precordial activity
that may indicate valvular obstruction or hypertrophic cardiomyopathy,
as well as the absence of gallops, murmurs, and abnormal peripheral
pulses. The neurologic exam should focus on discovering focal deficits.
++
An electrocardiogram is recommended for any child presenting with
syncope. In addition to confirming normal cardiac rhythm and age-appropriate heart rate, it
is important to manually confirm a normal QT interval (see Chapter 493). The QRS complexes should be inspected
for evidence of preexcitation (delta waves with shortened PR intervals
and broad QRS complexes) suggestive of Wolff-Parkinson-White syndrome
(see Chapter 485). Abnormal ST segments may
indicate ischemia, pericarditis, or a channelopathy such as Brugada syndrome.
Abnormally high QRS voltage could indicate chamber hypertrophy or
enlargement. Conversely, low voltage may indicate myocarditis.
++
Other testing may be indicated based upon the history, examination,
or electrocardiogram, but often serious pathology can be excluded
by this evaluation. Without concerning findings on history or physical
examination, echocardiography has not been shown to increase the
diagnosis of a serious disorder.25 Tilt table testing has
been used for diagnosis in patients with syncope but has poor reproducibility,
sensitivity, and specificity. The American College of Cardiology
and the Heart Rhythm Society no longer recommend tilt-testing for
patients with presentations typical for neurocardiogenic syncope.26
+++
Treatment of
Neurocardiogenic Syncope
++
For atypical presentations, worrisome family histories, or abnormalities
on physical examination or electrocardiography, referral for specialized
evaluation is warranted. However, once more serious disease is excluded
and if a diagnosis of neurocardiogenic syncope is established, therapy
is designed to minimize episodes. Foremost is the education of the
patient and family about the mechanism and avoidance of known triggers.
The maintenance of circulating volume status through hydration is
paramount.27 An active adolescent may need up to
4 L of fluid a day, depending on activities. Caffeine, because of
its sympathomimetic and diuretic effects, should be avoided. If
simple measures do not suffice, salt (250–1000 mg) can
be added to the diet. Fludrocortisone has been beneficial in some
patients,28 as have beta-blockers and α-agonists.29,30 If
syncope involves severe bradycardia, pacemaker therapy has been
employed with success.31
++
Systemic hypertension is often thought of as a disease of adults,
but in fact often has its antecedents in childhood or adolescence.
Management includes 3 discrete steps: detection by proper measurement
of blood pressure; correction of any structural, renal, or endocrine
causes. Among cardiac causes, coarctation of the aorta should be
considered. Despite the fact that this anomaly can be diagnosed
readily without the need for laboratory testing or imaging, coarctation
often goes undetected until adolescence or even adulthood.1 In
most patients with coarctation, but not all, femoral pulses are
diminished or totally absent. Whereas in normal subjects the supine systolic
blood pressure in the legs is higher than that in the arms, pressures
are reversed in the presence of coarctation. Arm pressures more
than 10 mm Hg higher than leg pressures should raise suspicion for
coarctation of the aorta.44 It is important to
use systolic, not mean or diastolic pressures, for
the diagnosis and follow-up of patients with coarctation. Normal blood
pressure standards, diagnostic workup, and pharmacologic therapy
of hypertension are discussed in Chapter 479.
+++
Pulmonary Hypertension
++
Pulmonary hypertension in children, as in adults, is extremely
serious (see Chapter 492).33-35 It
occurs in several situations in children and adolescents: Most common
is pulmonary hypertension associated with structural congenital
cardiac abnormalities, especially those with increased pulmonary
blood flow. Pulmonary hypertension is also seen in pediatric patients
with respiratory diseases, especially chronic lung disease of the
premature and late stages of cystic fibrosis. Although less common
in children than adults, pulmonary hypertension is also seen in
systemic disorders, including the hemoglobinopathies, thromboembolic
disease, and portal hypertension, and collagen vascular diseases,
such as scleroderma and systemic lupus erythematosus. Pulmonary
hypertension without an obvious underlying cardiac abnormality systemic
disease is referred to as idiopathic pulmonary hypertension.
++
Pulmonary hypertension is defined as a mean pulmonary artery
pressure of greater than 25 mmHg or greater than 30 mm Hg with exercise.
Although this definition is useful for clinical trials, its limitations
are that it often requires cardiac catheterization for an accurate
diagnosis and that it may be too high for infants and young children
in whom these values represent a much higher percentage of their
systemic arterial pressure than in adults.
+++
Pulmonary Hypertension Associated
with Congenital Heart Disease
++
Pulmonary hypertension is present in many congenital cardiac
abnormalities, especially those with increased pulmonary blood flow, large
communications between the ventricles or great arteries, and those
with obstruction to pulmonary venous return. Usually, the elevated
pulmonary artery pressure decreases if the underlying condition
is repaired or palliated within the first 1 or 2 years of life.
++
It is important to distinguish pulmonary hypertension from pulmonary
vascular obstructive disease. The former is simply elevation of pulmonary
artery pressure due to increased flow and pulmonary arteriolar vasoconstriction.
Pulmonary vascular obstructive disease is a late consequence of
uncorrected cardiac abnormalities and is characterized by irreversible
anatomic changes of the pulmonary arterial bed, including intimal sclerosis,
occlusion of small vessels, abnormal extension of vascular smooth
muscle into peripheral vessels, and reduction in the number of small
arteries.36 Reversal of a previous left-to-right shunt
(ie, Eisenmenger syndrome) is an ominous but late phenomenon. Pulmonary
vascular obstructive disease is uncommon in the first year of life,
and its incidence has decreased with earlier repair of many cardiac
defects. It tends to develop earlier in patients with hypoxemia
(transposition of the great arteries, truncus arteriosus), respiratory
disease, and Down syndrome.
++
Pulmonary vascular disease in adolescents and adults with congenital
heart disease is a multisystem disorder. Those affected typically
have decreased exercise capacity, chronic cyanosis, erythrocytosis,
and abnormal hemostasis.37 Patients are at risk for both
endocarditis and systemic infections, especially brain abscess.
Survival is longer than in idiopathic pulmonary hypertension, with
many patients living into the third or fourth decade.37,38
+++
Idiopathic Pulmonary Hypertension
++
Idiopathic pulmonary hypertension is typically a disease of young
adults, especially women, but it may occur in the second and even first
decade of life.39,40 Symptoms are nonspecific and include
fatigue, dyspnea, chest pain, and exercise intolerance. Syncope is
a late and ominous occurrence. Physical findings may be subtle and
include a right ventricular lift at the left sternal border and
accentuation of the pulmonary component of the second heart sound. Late
findings include murmurs of tricuspid or pulmonary insufficiency,
hepatomegaly, jugular venous distention, and peripheral edema. Survival
more than 5 years after diagnosis is rare.
++
Idiopathic pulmonary hypertension is a diagnosis of exclusion.
Patients with suspected or confirmed pulmonary hypertension should
undergo a comprehensive evaluation to attempt to establish a treatable
cause. This includes tests of pulmonary, coagulation, hepatic, and
thyroid function as well as assessment for connective tissue disease.35
+++
Treatment of
Pulmonary Hypertension
++
When treating pulmonary hypertension (see Chapter 492), the underlying disease state should be treated whenever
possible. For example, infants and children with enlarged tonsils
and upper airway obstruction may develop pulmonary hypertension
due to alveolar hypoxia. It is generally cured by a tonsillectomy
and adenoidectomy. Likewise, removal of a retropharyngeal or retrolaryngeal
mass relieves the hypoxia caused by these lesions. During sleep,
the rate and depth of respiration normally decrease, so that an elevation
in pulmonary vascular resistance associated with hypoxia increases
further during sleeping hours; thus, the delivery of positive airway
pressure via a mask may be helpful at night.
++
Hypoxic pulmonary vasoconstriction can be reversed by raising
alveolar oxygen tension or giving a pulmonary vasodilator. Because pulmonary
arterial hypertension causes muscular hypertrophy of the pulmonary
arterial wall, making it thicker and the lumen narrower, relief
of hypoxic vasoconstriction may not return pulmonary vascular resistance
to normal at once, but the hypertrophied smooth muscle of the media returns
to normal over several weeks. Although medial muscular hypertrophy
is reversed by repairing the cardiac defect, the intimal proliferative
changes of hyalinization and fibrosis are not reversible. However,
new alveoli and lung vessels still develop for a few years after
birth and mitigate the effect of these changes.
++
In older children with primary pulmonary hypertension, chronic
intravenous prostacyclin (PGI2) infusions may provide long-term reductions
in pulmonary vascular resistance and beneficial effects on symptoms,
as may sildenafil and bosentan. However, mortality remains high,
and therapy is often used as a bridge to transplantation. Reactive
pulmonary hypertension, particularly associated with correction
of congenital heart defects following cardiopulmonary bypass, may
respond acutely to vasodilators such as inhaled nitric oxide or
prostacyclin in addition to oxygen.