2. DEFINITION:
Myocarditis is defined as:
Acute or chronic inflammation of the
myocardium.
characterized by:
1. Inflammatory cells infiltrates in myocardium.
2. Myocyte degeneration or necrosis.
6. Continue:
Virus act on myocardium in three phases.
1) Virus Replication Or Acute Phase
2) Autoimmune Injury Phase
3) Dilated Cardiomyopathy Phase Or Chronic
Phase
7. Sign And Symptoms
Manifestations of myocarditis range from asymptomatic or
nonspecific generalized illness to acute cardiogenic shock and
sudden death.
Infants and young children more often have a fulminant
presentation with:
Fever.
Respiratory distress.
Tachycardia, hypotension, gallop rhythm, and cardiac
murmur.
Associated findings may include a rash or evidence of end
organ involvement such as hepatitis or aseptic meningitis.
8. Continue:
Patients with acute or chronic myocarditis may also
present with :
Palpitations, easy fatigability, or syncope.
Chest discomfort.
Cardiac findings include, gallop rhythm, and an apical
systolic murmur of mitral insufficiency.
In patients with associated pericardial disease, a rub
may be noted.
Hepatic enlargement, peripheral edema, and
pulmonary findings such as wheezes or rales may be
present in patients with decompensated congestive
heart failure
9. Diagnosis
1)-ELECTROCARDIOGRAPHIC CHANGES.
Nonspecific and may include sinus tachycardia, atrial
or ventricular arrhythmias, heart block.
2)-CHEST X.RAY:
Reveal cardiomegaly, pulmonary vascular prominence,
pulmonary edema, or pleural effusions.
3)-ECHOCARDIOGRAPHY:
Often shows diminished ventricular systolic function,
cardiac chamber enlargement, mitral insufficiency, and
occasionally, evidence of pericardial effusion.
10. Continue:
4)-Endomyocardial biopsy:
May be useful in identifying inflammatory cell
infiltrates or myocyte damage.
5)-OTHER SUPPORTIVE BUT NONSPECIFIC
TESTS INCLUDE:
Wbc’s often elevated.
ESR increased.
Troponins elevated in 1/3rd cases.
CK-MB may be elevated.
AST may be elevated.
11. Treatment
• Primary therapy for acute myocarditis is supportive
• Management is done according to clinical signs and
symptoms.
Conventional heart failure therapy is currently the
only accepted therapy for myocarditis including:
1. ACE inhibitors.
2. Angiotensin receptor blocking agents.
3. Diuretics.
4. β-blockers.
5. In patients manifesting with significant atrial or
ventricular arrhythmias, specific antiarrhythmic
agents (for example, amiodarone) should be given.
12. ROLE OF IMMUNOMODULATION
THERAPY.
Immunomodulation of patients with myocarditis is
controversial.
Intravenous immune globulin may have a role in
the treatment of acute or fulminant myocarditis.
Corticosteroids have been reported to improve
cardiac function, but the data are not convincing
in children.
Relapse has been noted in patients receiving
immunosuppression.
There are no studies to recommend specific
antiviral therapies for myocarditis.
13. Prognosis
The prognosis of symptomatic myocarditis:
in newborns is poor and 75% mortality has been
reported.
The prognosis is better for children and adolescents.
Recovery of ventricular function has been reported
in 10-50% of patients.