Acquired Heart Diseases Dr. khalil Ibrahim

Acquired Heart Diseases Acute rheumatic fever; cardiomyopathies; cardiovascular infections, including myocarditis and infective endocarditis; and non cngenital valvular heart disease are the most common acquired heart diseases among the pediatric age group patients.

Rheumatic Fever

DEFINITION Rheumatic fever is a delayed autoimmune reaction in genetically predisposed individuals to group A, β-hemolytic, streptococcal pharyngitis. It is a self-limited disease that may involve joints, skin, brain, serous surfaces, and the heart Despite the dramatic nature of the acute episode, ARF leaves no lasting damage to the brain, joints or skin.

Epidemiology The incidence of acute rheumatic fever is 3 to 61 per 100,000 school children. ARF is predominantly a disease of children aged 5-14 years and generally does not affect children less than 3 years old or adults. Acute rheumatic fever is most common during winter and spring, a seasonal variation similar to that of streptococcal pharyngitis.

CLINICAL MANIFESTATIONS Acute rheumatic fever is diagnosed using the revised Jones criteria, which consist of clinical and laboratory findings . The presence of either two major criteria or one major and two minor criteria, along with evidence of an antecedent streptococcal infection, confirm a diagnosis of acute rheumatic fever. The infection often precedes the presentation of rheumatic fever by 2 to 6 weeks.

Supporting evidence of a preceding streptococcal infection 1. Elevated or rising antistreptolysin-O or other streptococcal antibody, or 2. Rapid antigen test for group A streptococci, or 3. A positive throat culture, or 4.Recent scarlet fever.

Laboratory Findings High ESR . Anemia, leucocytosis . Elevated C-reactive protein . ASO titre >200 Todd units Anti-DNAse B test . Throat culture-GABH streptococci .

7. ECG- prolonged PRinterval, 2nd or 3rd degree blocks , ST depression or Tinversion. 8. 2D Echo cardiography - valve edema ,mitral regurgitation, LA & LV dilatation, pericardial effusion, decreased contractility.

Management 1-Benzathine penicillin G, 0.6 to 1.2 million units intramuscularly, is given to eradicate streptococci. This serves as the first dose of penicillin prophylaxis as well . In patients allergic to penicillin, erythromycin, 40 mg/kg per day in two to four doses for 10 days, may be substituted for penicillin.

2-Bed rest of varying duration is recommended 2-Bed rest of varying duration is recommended. The duration depends on the type and severity of the manifestations and may range from a week (for isolated arthritis) to several weeks for severe carditis . Bed rest is followed by a period of indoor ambulation of varying duration before the child is allowed to return to school.

3-Therapy with anti-inflammatory agents should be started as soon as acute rheumatic fever has been diagnosed as follows. Prednisone, 2 mg/kg/24 hours in 4 divided doses. Aspirin, 100 mg/kg/d in4-6 divided doses.

4-Treatment of CHF includes the following a. Complete bed rest with O2 4-Treatment of CHF includes the following a. Complete bed rest with O2. b. Prednisone for severe carditis of recent onset c. Digoxin, used with caution, beginning with half the usual recommended dose, because certain patients with rheumatic carditis are supersensitive to digitalis. d. Furosemide,1 mg/kg every 6 to 12 hour.

5-Management of Sydenham's chorea Reduce physical and emotional stress. For severe cases, any of the following drugs may be used: phenobarbital , haloperidol ,valproic acid, chlorpromazine (Thorazine), diazepam (Valium), or steroids.

Prevention (prophylaxis) A patient who has had acute rheumatic fever is susceptible to recurrent rheumatic fever for the rest of his life.

Recommended Duration of Prophylaxis for Rheumatic Fever Rheumatic fever with carditis and residual heart disease (persistent valvular disease) Rheumatic fever with carditis but without residual heart disease (no valvular disease) Rheumatic fever without carditis Category At least 10 yr since last episode and at least until age 40 yr; sometimes lifelong prophylaxis At least for 10 yr or well into adulthood, whichever is longer At least for 5 yr or until age 21 yr, whichever is longer Durartion

Cardiomyopathies Primary myocardial disease, or cardiomyopathy, is a disease of the heart muscle itself, not associated with congenital, valvular, or coronary heart disease or systemic disorders. Cardiomyopathy has been classified into three types based on anatomic and functional features: hypertrophic, dilated (or congestive), and restrictive

Features of different types Restrictive Dilated Hypertrophic Feature Myocardial fibrosis, hypertrophy, or infiltration (amyloid, hemochromatosis) Pluricausal (e.g., toxic, metabolic, infectious, alcohol, doxorubicin) Inherited (AD in about 50%) Sporadic (new mutation ±) Etiology Diastolic dysfunction (with normal systolic function) (abnormally stiff LV with impaired ventricular filling) Systolic contractile dysfunction (↓ cardiac output, ↓ stroke volume, ↑ LVEDP) Diastolic dysfunction (rigid ventricular walls impede ventricular filling) Hemodynamic dysfunction

Restrictive Dilated Hypertrophic Feature Exercise intolerance, weakness and dyspnea, or chest pain. signs and symptoms of inadequate cardiac output and CHF. Infants, frequently present with signs of CHF. Older children may be asymptomatic, with sudden death as the initial presentation. Dyspnea, fatigue, chest pain, syncope or near-syncope, and palpitations may be present. Symptoms

Restrictive Dilated Hypertrophic Feature Jugular venous distention, gallop rhythm, and a systolic murmur of AV valve regurgitation may be present. Features of CHF. Rales may be audible on pulmonary auscultation. Heart sounds may be muffled, and S3 is often present. Concurrent infectious illness may result in circulatory collapse and shock in children with dilated cardiomyopathies. A murmur is heard in more than 50% of children. On examination

Restrictive Dilated Hypertrophic Feature Biatrial enlargement Biventricular dilatation and EF% Thickened LV (and occasionally RV) wall Echocardiography Atrial hypertrophy. It may show atrial fibrillation and paroxysms of supraventricular tachycardia. Sinus tachycardia, LVH, and ST-T changes are the most common findings. (LVH), ST-T changes, and abnormally deep Q waves (owing to septal hypertrophy) Electrocardiography cardiomegaly, pulmonary venous congestion, and occasional pleural effusion. Generalized cardiomegaly is usually present, with or without signs of pulmonary venous hypertension or pulmonary edema. Mild left ventricular enlargement with a globular-shaped heart. Chest x ray

Restrictive Dilated Hypertrophic Feature -Diuretics -Anticoagulants (±) -Corticosteroids (±) -Permanent pacemaker for advanced heart block (±) -Cardiac transplantation (±) -Vasodilator therapy -Digitalis plus diuretics -β-Adrenoceptor blockers (±) Antiarrhythmics (±) Cardiac transplantation (±) -β-Adrenoreceptor blockers -Calcium antagonists -(Digitalis/catechols ,Diuretics and nitrates are contraindicated). Treatment