Download myocard*al and per*card*al d*seases

MYOCARDIAL and
PERICARDIAL DISEASES
The extremely heterogeneous heart muscle diseases associated with structural remodeling
and/or abnormalities of cardiac function (cardiomyopathy) are important causes of
morbidity and mortality in the pediatric population.
Dilated cardiomyopathy: The most common form of cardiomyopathy, is characterized
predominantly by left ventricular dilation and decreased left ventricular systolic function
.
Hypertrophic cardiomyopathy : Increased ventricular myocardial wall thickness, normal
or increased systolic function, and often, diastolic (relaxation) abnormalities .
Restrictive cardio- myopathy: Nearly normal ventricular chamber size and wall
thickness with preserved systolic function, but dramatically impaired diastolic function
leading to elevated filling pressures and atrial enlargement.
DILATED CARDIOMYOPATHY (DCM)
The most common form of cardiomyopathy in children,
•
Cause of significant morbidity and mortality as well as a common indication for
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cardiac transplantation.
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Unlike adult patients with DCM, ischemic etiologies are rare in children;
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anomalous origin of the left coronary artery from the pulmonary artery,
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premature coronary atherosclerosis (homozygous type II hypercholesterolemia)
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coronary inflammatory diseases( Kawasaki disease).
50% of cases are genetic (usually autosomal dominant; some autosomal
recessive or X-linked.
Annual incidence of DCM in children younger than 18 yr is 0.57 cases per 100,000 per year.
Incidence is higher in males, African-Americans, and in infants less than 1 yr old.
MOST COMMON ETIOLGY REMAINS IDIOPATHIC
Pathogenesis:
 The pathogenesis of ventricular dilatation and altered contractility varies
depending on the underlying etiology;SYSTOLIC DYSFUNCTION +
MYOCYTE INJURY common.
 Genetic abnormalities of several components of cardiac muscle (sarcomere
protein, cytoskeleton, proteins that bridge the contractile apparatus to the
cytoskeleton)
Autosomal dominant or X-linked inherited disorders
 Viral myocarditis ,viral induced inflammatory injury result in myocardial
damage ,ventricular enlargement and poor function.
 Anthracycline cardiotoxicity (doxorubicin) causes acute inflammatory
myocardial injury, more clasiccaly results in DCM.
Clinical Manifestations:
 Palpitations, syncope,sudden death.
 Nonspesific complaints: Irritability,lethargy, failure to thrive
,nausea,vomiting.
 Signs of heart failure: Respiratory symptoms ( tachypnea,
cough,dypnea on exertion).
 Hepatic enlargement, rales or wheezing.
 Auscultation: gallop rhythm,tachycardia, murmurs of mitral and
tricuspid (less commonly) insufficiency.
 Presence of hypoglycaemia, acidosis, hypotonia or signs of liver
dysfunction suggests an inborn errors of metabolism.
 Neurologic or skelatal muscle deficits are associated with
mitochondrial disorders or muscular dystrophies.
Labrotory Findings :
 ECG:
 atrial or ventricular hypertrophy ,
 nonspesfic T-wave abnormalities,
 atrial or ventricular arryhmias
 CHEST X RAY:
 cardiomegly
 pulmonary vascular prominence
 pleural effusions
 ECHO: diagnostic
 LV enlargement
 decreased ventricular contractility,
 RV enlargement and depressed function.
 ECHO DOPPLER:
 pulmonary hypertension
 mitral regurgitation
Additional testing should include: complete blood count, renal and liver function tests,
creatine phosphokinase, cardiac troponin I, lactate, plasma amino acids, urine organic acids,
and acylcarnitine profile.
•
Additional genetic and enzymatic testing may be useful .
•
Cardiac catheterization and endomyocardial biopsy are not routine but may be useful in
patients with acute DCM. Biopsy samples can be examined histologically for the
presence of mononuclear cell infiltrates, myocardial damage, storage abnormalities,
and for evidence of infection.
•
It is considered standard of care to screen 1st-degree family members utilizing
echocardiography and electrocardiogram (ECG) in idiopathic and familial cases of DCM.
Prognosis&Management

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DCM is the most common cause for cardiac transplantation in pediatric and adult studies.
The therapeutic approach careful assessment to uncover possible treatable etiologies,
screening of
family member, rigorous pharmacologic therapy.

Decongestive therapy may improve symptoms of heart failure, prolong survival, and occasionally results in
complete resolution of dysfunction.

Diuretics and ACE inhibitors.

Digitalis and angiotensin receptor blockers.

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β-Adrenergic blockade with carvedilol or metoprolol is often used in patients with chronic heart failure.
In patients presenting with extreme degrees of heart failure or circulatory collapse intravenous inotropes
and diuretics, mechanic ventilatory support,mechanical circulatory support, extracorporeal membrane
oxygenation (ECMO), and ultimately cardiac transplantation.

In patients with DCM and atrial or ventricular arrhythmias, specifc antiarrhythmic therapy should be used.
HYPERTROPHIC CARDIOMYOPATHY (HCM)
• Potentially life-threatening form of cardiomyopathy.
• The causes of HCM are heterogeneous:
• Inborn errors of metabolism
• Neuromuscular disorders
• Syndromic conditions, and genetic abnormalities of the structural
components of the cardiomyocyte.
• Both the age of onset and associated features are helpful in identifying the
underlying etiology.
Pathogenesis:
 Presence of increased left ventricular wall thickness in the absence of structural heart disease or hypertension.
 Interventricular septum is disproportionately involved, leading to the previous designation of idiopathic
hypertrophic subaortic stenosis (current term of asymmetric septal hypertrophy.)
 Although the left ventricle is predominantly affected, the right ventricle may be involved, particularly in
infancy.
 Mitral valve can demonstrate systolic anterior motion and mitral insufficiency. Left ventricular outflow tract
obstruction occurs in 25% of patients, and may in part be secondary to the abnormal position of the mitral
valve as well as the obstructing subaortic hypertrophic cardiac muscle.
 The cardiac myofibrils and myofilaments demonstrate disarray and myocardial fibrosis.
 Systolic pump function is preserved or even hyperdynamic, though systolic dysfunction may occur late.
 Outflow tract obstruction with or without mitral insufficiency may be provoked by physiologic manipulations
(positional changes, and physical activity).
 Hypertrophic and fibrosed cardiac muscle demonstrates relaxation abnormalities (diminished
compliance) and left ventricular filling may be impaired (diastolic dysfunction).
Clinical Manfestations:
 Many patient are asymptomatic.%50 cases present with a heart murmur
or during screening when other family member has been diagnosed with
heart HCM.
 Palpitations, chest pain, easy fatiguability, dyspnea, dizziness and
syncope.
 Sudden death is well recognised but uncommon manifestation, often
occurs during physical exertion.
 Abnormal peripheral pulses (hyperdynamic or diminished),
 Systolic ejection murmur in the aortic region.
 Apical murmur of mitral insufficiency.
Labrotory Findings:
 ECG:
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Left ventricular hypertrophy (S wave in V1 + R wave in V5 or V6 ≥ 35 mm
R wave > 11 mm in aVL
ST segment and T-wave abnormalities,
 Intraventricular conduction delay
 CHEST X RAY:
 Normal or mildly increased heart size with a prominent left ventricle
 ECHO: diagnostic
 Concentric LV hypertrophy
 Asymmetric septal hypertrophy
ECHO DOPPLER:
 Diastolic dysfunction
 Additional diagnostic studies include metabolic testing, genetic testing for speci c syndromes,
or genetic testing for mutations in genes known to cause isolated HCM
Prognosis&Management:
 Children under 1 yr of age or with inborn errors of metabolism or
malformation syndromes or those with a mixed HCM/DCM have a
signifcantly poorer prognosis.
 Competitive sports and strenuous physical activity should be prohibited.
 β-adrenergic blocking agents (propranolol, atenolol) or calcium
channel blocking agents (verapamil) may be useful in diminishing
ventricular outflow tract obstruction, modifying ventricular hypertrophy,
and improving ventricular filling. Although signifi cant symptomatic
improvement occurs in some patients, the risk for development of
heart failure or sudden death has not been lessened.
 In patients with atrial or ventricular arrhythmias, specific antiarrhythmic
therapy should be used.
 First-degree relatives of patients identified as having HCM should be
screened with electrocardiography and echocardiography.
RESTRICTIVE CARDIOMYOPATHY
(RCM)
 Accounts for <5% of cardiomyopathy cases.
 Incidence increases with age, and is more common in
females.
 Infiltrative myocardial causes and storage disorders
frequently result in associated left ventricular hypertrophy
and may represent HCM with restrictive physiology.
 Nonininfiltrative causes include mutations in genes
encoding sarcomeric or cytoskeletal proteins.
 Majority are considered idiopathic.
Pathogenesis:
 Normal ventricular wall dimensions
 Normal myocardial wall thickness
 Preserved systolic function
 Dramatic atrial diletation as a result of the abnormal
myocardial compliance and high ventricular diastolic
pressure.
Clinical Manifestations:
 Abnormal vetricular filling (diastolic heart failure);
edema,hepatomegaly, ascites.
 Elevation of left-sided filling pressures; dypnea,
cough,pulmonary edema.
 With activity  chest pain ,shortness of
breath,syncope-near syncope or even sudden death.
 Pulmonary hypertension and pulmonary vascular
disease develop and may progress rapidly. Pronounced
pulmonary component of the second heart sound are
present.
 Heart murmurs are typically absent, but a gallop rhythm
may be prominent.
Labrotory Findings:
 ECG:
Prominent p waves with normal QRS voltages
Nonspesific ST and T-wave changes
RVH (in patients who develop PHT) (r wave tall in v1 v2)
 CHEST X RAY:
 Normal or prominent atrial shadow and pulmonary vascular redistribution
ECHO: diagnostic
 Normal sized ventricles with preserved systolic function
 Dramatic enlargement of atria
ECHO DOPPLER:
 Abnormal filling parameters
 Differential diagnosis from constrictive pericarditis is critical (can be treated surgically).
 MRI may be necessary to demonstrate the thickened or calcifed pericardium often present in
constrictive pericardial disease.
Prognosis and Management
 Pharmacologic treatment :limited use
 Prognosis :poor ,progressive clinical deterioration.
 When signs of heart failure exist, use of diuretics can
result in clinical improvement.
 Dramatic atrial enlargementpredisposed to atrial
tachyarrhythmias and thromboemboli.Antiarrhythmic
agents+ anticoagulation with platelet inhibitors or
Coumadin is indicated.
 Cardiac transplantation is the treatment of choice,and the
results are excellent in patients without pulmonary
hypertension, pulmonary vascular disease, or severe
congestive heart failure.
MYOCARDITIS
 Acute or chronic inflammation of the myocardium by
inflammatory cell infiltrates, myocyte necrosis, or myocyte
degeneration.
 May be caused by: INFECTIOUS,CONNECTIVE
TISSUE,GRANULAMATOUS, TOXIC ,IDIOPATHIC,IMMUNE
DISORDERS,HYPERSENSITIVITY REACTIONS.
 Patients may be asymptomatic, have nonspecific prodromal
symptoms, or present with overt congestive heart failure,
compromising arrhythmias, or sudden death.
 Viral infections are the most common etiology
Pathophisiology:
 Myocardial inflammation, injury or necrosis fibrosis.

Cardiac enlargement+ diminished systolic function as a direct result of the
myocardial damage. Typical signs of congestive heart failure occur and may
progress rapidly to shock, atrial or ventricular arrhythmias, and sudden
death.
 Viral myocarditis may also become a chronic process with persistence of viral
nucleic acid in the myocardium, and the perpetuation of chronic inflammation
secondary to altered host immune response including activated T
lymphocytes (cytotoxic and natural killer cells) and antibody-dependent cell
mediated damage.
 Some viral proteins share antigenic epitopes with
host cells, resulting in autoimmune damage to the
antigenically related myocyte.
 Cytokines (TNF-α and IL-1) are inhibitors of myocyte
response to adrenergic stimuli, result in diminished
cardiac function. Final result of viral-associated
inflammation can be DCM.
Clinical Manifestations
 Previous viral respiratory tract infection or diarhhea
present.
 Signs and syptoms change according to age.
 Neonates: Fever,fatigue,pallor, inability to feed, sudden
death
 Congestive heart failure signs in physical examination.
 Older children: Previous viral respiratory tract infection or
diarhhea (10-14 days ago)
 Fever,pallor, decreased appetite, dypnea,chest
pain,vomiting,abdominal pain ,syncope, cardiac arrest.
 Physical examination: tachycardia (when resting and without
fever),CHF signs,arrythmias.
Diagnosis:
 ECG: sinus tachycardia, low voltage QRS, low voltage T
wave or inverse T wave.
 Wide Q,ST segment changes mimicking MI.
 Tachy-brady arrythmias (VT,SVT, AF,AV block)
 Telecardiography: Normal or enlarged heart
 Pulmonary congestion,pleural effusions,interstitial
infiltrates.
 Echo: Diminished ventricular systolic funtion
 Cardiac chamber enlargement
 Mitral insufficiency
 Pericardial effusion
 Cardiac MRI :presence and extent of edema,
gadolinium-enhanced hyperemic capillary leak, myocyte
necrosis, left ventricular dysfunction, pericardial effusion
.
 Endomyocardial biopsy inflammatory cell infiltrates or
myocyte damage + molecular viral analysis using PCR
techniques.
 Nonspecific tests (serum findings of myocardial
damage):, creatine phosphokinase isoenzymes CK-MB,
cardiac troponin I ,AST levels.
 Acute phase reactants: CRP, sedimentation
Differential Diagnosis:
 Newborns:
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Sepsis
Hypoxia
Hypoglycemia
Hypocalcemia
Congenital heart diseases
Idiopathic DCM
Coronary anomalies
 Other children:
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Idiopathic DCM
Coronary anomalies
Chronic tachycardia
Pericarditis
Treatment:
 Primary therapy for acute myocarditis is supportive.
 Bed rest, activity restrictions
 Respiratory distress: O2 treatment.
 Anticongestive treatment: Acutely, inotropic agents (milrinone), should be
entertained but used with caution because of their proarrhythmic potential.
 Diuretics (Furosemide), ACE inhibitors (captopril), ARBs are of use in
patients with compensated congestive heart failure
 Digoxin : controlled+half dose ( damaged myocardial cells).
 If in extremis, mechanical ventilatory support+ mechanical circulatory
support (ECMO) may be needed to stabilize the patient’s hemodynamic
status and serve as a bridge to recovery or cardiac transplantation.
 Signifcant atrial or ventricular arrhythmiasspecific antiarrhythmic agents
(amiodarone) .
 Immunomodulation controversial.
 Intravenous immune globulin may have a role in the
treatment of acute or fulminant myocarditis (effective in
Kawasaki)
 Corticosteroids have been reported to improve cardiac function,
but the data are not convincing in children. (first 7 days may
increase viral replication).
 Relapse has been noted in patients receiving
immunosuppression who have been weaned from support.
 Ribavirin: May inhibit Coxackievirus replication when used
acutely. (same effect with α,βIFN).
Prognosis:
 Newborns poor, 75% mortality .
 Thee prognosis is better for children and adolescents,
although patients who have persistent evidence of DCM
often progress to need for cardiac transplantation.
 Recovery of ventricular function has been reported in
10-50% of patients, however.
DISEASES OF
PERICARDIUM
 The heart is enveloped in a bilayer membrane, the
pericardium, which normally contains a small amount of
serous fluid.
 The pericardium is not vital to normal function of the
heart, and primary diseases of the pericardium are
uncommon. However, the pericardium may be a
affected by a variety of conditions, manifestation of a
systemic illness and can result in serious, even lifethreatening, cardiac compromise.
ETIOLOGY OF PERICARDIAL DISEASE
 CONGENITAL
 Absence (partial, complete)
Cysts
Mulibrey nanism (TRIM 37 gene mutation) Camptodactyly-arthropathy-coxa
vara-pericarditis syndrome (PRG4
 INFECTIOUS
 Viral (coxsackievirus B, Epstein-Barr virus, influenza, adenovirus, parvovirus,
HIV, mumps)
 Bacterial (Haemophilus influenzae, streptococcus, pneumococcus,
staphylococcus, meningococcus, mycoplasma, tularemia, listeria, leptospirosis,
tuberculosis, Q-fever, salmonella)
 Immune complex (meningococcus, H. influenzae) Fungal (actinomycosis,
histoplasmosis)
Parasitic (toxoplasmosis, echinococcosis)
 NONINFECTIOUS
 Idiopathic
Systemic inflammatory diseases (acute rheumatic fever, juvenile
idiopathic arthritis, systemic lupus erythematosus, mixed
connective tissue disorders, systemic sclerosis, Kawasaki disease,
Churg-Strauss syndrome, Behçet syndrome, sarcoidosis, familial
Mediterranean fever and other recurrent fever syndromes,
pancreatitis, granulomatosis with polyangiitis)
 Metabolic (uremia, hypothyroidism, Gaucher disease, very-longchain acyl-CoA dehydrogenase deficiency)
 Traumatic (surgical, catheter, blunt) Lymphomas, leukemia,
radiation therapy, Primary pericardial tumors
Pathogenesis:
 When the amount of fluid in the nondistensible pericardial space becomes
excessive, pressure in the pericardium increases ,resulting in impaired filling.
 Small to moderate amounts of pericardial effusion can be well tolerated and
clinically silent, once the noncompliant pericardium has been distended
maximally, any further fluid accumulation causes abrupt impairment of cardiac
filling and is termed cardiac tamponade.
 When untreated, tamponade can lead to shock and death.
 With the development of pericardial tamponade, several compensatory
mechanisms are triggered:
 systemic and pulmonary venous constriction to improve diastolic filling,
 an increase in SVR to raise falling blood pressure, and
 tachycardia to improve cardiac output.

Pericardial effusions may be serous/transudative, exudative/purulent,
fibrinous, or hemorrhagic.
Clinical Manifestations:
 Chest pain (sharp/stabbing, positional, radiating, worse with
inspiration, and relieved by sitting upright or prone).
 Cough, fever, dyspnea, abdominal pain, and vomiting are
nonspecific symptoms associated with pericarditis.
 Distant heart sounds, tachycardia, narrow pulse pressure,
jugular venous distention, and a pericardial friction rub
provide clues to the diagnosis of acute pericarditis.
 Cardiac tamponade is recognized by the excessive fall of
systolic blood pressure (>10 mm Hg) with inspiration.
Diagnosis:
 ECG:, low voltage QRS, low voltage T wave
 Tachycardia and abnornormalities of the ST segments
(elevation mimicing acute MI, PR segments(depression),
and T waves(inversion).
 Telecardiography: Normal without effusion or enlarged
heart
 Echo: identify size an location of pericardial fluid.
Compression and collapse of the right atrium and/RV
Abnormal diastolic filling during tamponade.
Differential Diagnosis:
 Chest pain similar to that present in pericarditis can
occur with lung diseases, especially pleuritis, and with
gastroesophageal reflux.
 Pain related to myocardial ischemia is usually more
severe, more prolonged, and occurs with exercise,
allowing distinction from pericarditis-induced pain.
Infectious pericarditis

Clinical course majority of these infections is mild and spontaneously resolving.

Enteroviruses, influenza, adenovirus, respiratory syncytial virus, and parvovirus.

Course is usually benign, symptomatic treatment with nonsteroidal antiinfl ammatory
agents is often suffcient.

Large effusions and tamponade may require pericardiocentesis.

In up to 30%, there may be recurrences of pericarditis. Treatment and/or prevention of
recurrences with colchicine improve symptoms -, avoid recurrences Patients with
idiopathic recurrent pericarditis may also respond to treatment with anakinra.

Chronic or relapsing, surgical pericardiectomy or creation of a pericardial window may be
necessary.

Echocardiography differentiates pericarditis from myocarditis, the latter diminished
myocardial contractility or valvular dysfunction. Pericarditis and myocarditis may occur
together in some cases of viral infection.
 Purulant pericarditis (bacterial) much less common.
More aggressive progression.
 Tuberculous pericarditis is rare, causes constructive
pericarditis.
Noninfectious Pericarditis
 Systemic inflammatory diseases (autoimmune, rheumatologic, and
connective tissue disorders) may involve the pericardium and result in
serous pericardial effusions.
 Pericardial inflammation may be a component of the type II
hypersensitivity reaction seen in patients with acute rheumatic fever. It is
associated with rheumatic valvulitis and responds quickly to
antiinflammatory agents including steroids.
 Tamponade is very uncommon.
 Postpericardiotomy syndrome occurs in patients having undergone
cardiac surgery and is characterized by fever, lethargy, anorexia,
irritability, and chest/abdominal discomfort beginning 7-14 days
postoperatively. Postpericardiotomy syndrome is effectively treated with
aspirin, nonsteroidal antiinflammatory agents.
CONSTRICTIVE
PERICARDITIS
 Rarely, chronic pericardial inflammation can result in
fibrosis, calcication, and thickening of the pericardium.
 Pericardial scarring may lead to impaired cardiac
distensibility and filling .
 Constrictive pericarditis can occur following :
 recurrent or chronic pericarditis,
 cardiac surgery, or radiation to the mediastinum
Clinical Manifestations
 Clinical manifestations of systemic venous hypertension
predominate
 Jugular venous distention,
 peripheral edema,
 Hepatomegaly, ascites
 Tachycardia,
 Hypotension,
 Pulsus paradoxus.
 Pericardial knock, rub, and distant heart sounds might be
present on auscultation.
 Abnormalities of liver function tests, hypoalbuminemia,
hypoproteinemia, and lymphopenia may be present.
 X-rays of the chest demonstrate calcifications of the
pericardium.
 Constrictive pericarditis may be difficult to distinguish
clinically from restrictive cardiomyopathy as both conditions
result in impaired myocardial filling.
 Echocardiography may be helpful in distinguishing
constrictive pericardial disease from restrictive
cardiomyopathy, but magnetic resonance imaging and
computed tomographic imaging are more sensitive in
detecting abnormalities of the pericardium.
 Although acute pericardial constriction is reported to respond
to antiinflammatory agents, the more typical chronic
constrictive pericarditis will respond only to surgical
pericardiectomy with extensive resection of the pericardium.