RHEUMATIC HEART DISEASE HA MWAKYOMA, MD

Introduction Rheumatic heart disease is the most serious manifestation of acute rheumatic fever and is the end result of carditis, which affects 30% to 45% of patients with acute rheumatic fever.

Introduction—cont-- Damage to the cardiac valves may be chronic and progressive and can lead to congestive heart failure and death Pockets of resurgence of rheumatic fever have occurred all over the world in recent years

Epidemiology Acute rheumatic fever is a disease of the young, occurring most commonly in preadolescent children It is much rarer in children younger than 5 years and adults older than 35 years

Epidemiology—cont-- Recurrent episodes occur through adolescence and into early adulthood, and it is thought that the cumulative effect of recurrent episodes of acute rheumatic fever leads to the development of rheumatic heart disease Both acute rheumatic fever and rheumatic heart disease are more common in females

Pathogenesis Incompletely understood; Although streptococci have not been found in the heart tissues of patients with acute rheumatic fever, there is strong circumstantial evidence that acute rheumatic fever is the result of an exaggerrated immune response to pharyngeal infection with group A streptococcus.

Pathogenesis-cont-- Outbreaks of acute rheumatic fever closely follow epidemics of streptococcal pharyngitis or scarlet fever, and adequate treatment of documented pharyngeal streptococcal infection clearly decreases the incidence of subsequent rheumatic fever.

Pathogenesis-cont-- Appropriate prophylaxis with antibiotics can prevent recurrence in patients with prior episodes of acute rheumatic fever

Pathogenesis—cont-- Most patients with acute rheumatic fever also have elevated titers to one or more of the three antistreptococcal antibodies (streptolysin O, hyaluronidase, and streptokinase). Group A streptococcal infection of the pharynx is a necessary element for the subsequent development of acute rheumatic fever

Valvular Heart Diseases Heart -Pathology Valvular Heart Diseases Rheumatic Heart Disease (RHD) Rheumatic Fever (RF) Acute, immune-mediated multi-system disease occurring a few weeks after an episode of group A streptococcal pharyngitis MC in children 5-15 yrs old RF  RHD (deforming fibrotic valvular disease) After first attack -  susceptibility to reactivation of RF with subsequent pharyngitis

Rheumatic Heart Diseases Heart -Pathology Rheumatic Heart Diseases Etiopathogenesis Hypersensitivity ( immunological) reaction to “M” protein of Group A streptococci RF develops weeks after Streptococcal pharyngitis Antibodies against “M” protein cross react with Cardiolipins of Heart Rheumatic disease GBM of Kidney  Post – streptococcal Glomerulonephritis (PIGN/PSGN/ Acute nephritic syndrome)

Morphology Acute (RF) Aschoff bodies (Myxoid degerantion with surrounding inflammation), Pancarditis, Anitschkow cells (macrophages with caterpillar like nucleus) Chronic (RHD) fibrosis of valve cusps, fusion of commisures,

Rheumatic Heart Diseases Heart -Pathology Rheumatic Heart Diseases

Clinical Features Onset of acute rheumatic fever is typically characterized by an acute febrile illness 2 to 4 weeks after an episode of pharyngitis. Diagnosis is primarily clinical and is based on a constellation of signs and symptoms, which were initially established as the Jones criteria in 1944:

Jones Criteria (1992 Revision) for Diagnosis of Acute Rheumatic Fever Major manifestations Carditis Polyarthritis Chorea Erythema marginatum Subcutaneous nodules

Jones Criteria (1992 Revision) for Diagnosis of Acute Rheumatic Fever– cont-- Minor manifestations Fever Arthralgias Previous rheumatic fever or rheumatic heart disease Increased C- reactive protein concentrations or ESR Prolonged PR interval on ECG Evidence of antecedent group A streptococcal infection Positive throat culture or rapid antigen test positive for group A streptococcus Increased or increasing streptococcal antibody titer

The Jones Criteria for Rheumatic Fever, Updated 1992 Major Criteria Minor Criteria   Carditis Clinical Migratory polyarthritis Fever Sydenham's chorea Arthralgia Subcutaneous nodules Laboratory Erythema marginatum Elevated acute phase reactants Prolonged PR interval plus Supporting evidence of a recent group A streptococcal infection (e.g., positive throat culture or rapid antigen detection test; and/ or elevated or increasing streptococcal antibody test)

Jones Criteria (1992 Revision) for Diagnosis of Acute Rheumatic Fever A firm diagnosis requires 2 major manifestations or 1 major and 2 minor manifestations and 2 ) Evidence of a recent streptococcal infection. However, when chorea or carditis is clearly present, evidence of an antecedent group A streptococcal infection is not necessary.

Rheumatic Heart Diseases Heart -Pathology Rheumatic Heart Diseases Types Feature Rheumatic Fever (RF) Rheumatic Heart Disease (RHD Onset Acute Chronic Age Children ( 5 – 15 yrs) Adults Pathology Carditis, arthritis, chorea Valvular disease ( MS, MR) Aschoff bodies Pathognomonic Not seen Diagnosis John’s criteria Not applicable

Clinical Features Although the clinical usefulness of the Jones criteria has been recently reaffirmed, the main features have been modified or updated several times in order to increase the specificity of the criteria. The World Health Association (WHO) has more recently developed criteria that favor sensitivity over specificity; they may be the preferred guidelines in countries with populations at high risk for acute rheumatic fever

World Health Association for Diagnosis of Acute Rheumatic Fever First episode- same as the Jones criteria Recurrent episode in a patient without established RHD- same as for first episode Recurrent episode in a patient with established RHD- requires 2 minor Jones criteria manifestations and evidence of an antecedent gropu A streptococcus infection

Clinical Features Beyond fever, arthritis is typically the earliest manifestation of acute rheumatic fever. In untreated patients, the arthritis is classically described as “migrating” from joint to joint in quick succession. The knees and ankles are often the first affected. The duration of joint inflammation is short (≤ 1 week), and the synovial fluid is generally sterile when examined.

Chorea, also known as Sydenham chorea or St. Vitus dance, Clinical Features Chorea, also known as Sydenham chorea or St. Vitus dance, is a neurologic movement disorder characterized by abrupt, purposeless involuntary movements of the muscles of the face, neck, trunk, and limbs. Muscular weakness (hypotonia) and behavioral disturbances such as obsessive- compulsive behaviors are considered to be additional findings of chorea. .

Chorea-- Clinical Features—cont-- The course of the syndrome is variable. Symptoms tend to develop subtly, progressively worsen over 1 to 2 months, and spontaneously resolve gradually after 3 to 6 months. Residual waxing and waning of symptoms may occur for a year or more, and 20% of patients have recurrences within 2 years

Clinical Features Two classic skin lesions with well-described identifying characteristics occur in acute rheumatic fever: Subcutaneous nodules ranging from several millimeters to 2 cm occur for approximately 2 weeks over bony surfaces or near tendons. The nodules are described as firm and painless, and the overlying skin is not inflamed. They are typically smaller and shorter lived than nodules of rheumatoid arthritis.

Subcutaneous nodule

Clinical Features—cont-- Erythema marginatum is a classic skin rash that occurs early in the course of acute rheumatic fever. The rash is evanescent, pink to red and nonpruritic. It typically occurs on the trunk or proximal limbs.

Erythema marginatum The rash appears as a ring that extends centrifugally, while the skin in the center of the ring returns to normal. The rash can persist or recur after other symptoms of acute rheumatic fever have passed. Interestingly, erythema marginatum and the subcutaneous nodules usually occur only in patients with carditis.

Erytherma marginatum

Erytherma marginatum

Carditis and Rheumatic Heart Disease The term carditis refers to diffuse inflammation of the pericardium, epicardium, myocardium, and endocardium. Valvular involvement, with leaflet thickening, occurs as a rule; in addition, the valves frequently display small rows of vegetations called verrucae along their appointing surfaces.

Carditis and Rheumatic Heart Disease Symptoms include tachycardia and mild or moderate chest discomfort that is commonly pleuritic in nature.

Rheumatic Heart Diseases Heart -Pathology Rheumatic Heart Diseases Commissural fusion

Vagetations

RHD:-(thickened mitral valve, thickened chordae tendineae, hypertrophied left ventricular myocardium).

Carditis and Rheumatic Heart Disease The cardiac physical examination often reveals the presence of pericardial friction rub and typically, new or changing murmurs. In young patients, mitral valve regurgitation is the predominant cardiac lesion A new apical systolic murmur is characteristic Aortic regurgitation is less common but can develop

The pulmonary and tricuspid valves are rarely involved Mitral stenosis becomes progressively more common in early to mid adulthood. Heart block of all degrees is seen on ECGs The most common radiologic finding is cardiomegaly.

Carditis and Rheumatic Heart Disease Myocarditis is characterized by infiltration of mononuclear cells, vasculitis, and degenerative changes of the insterstitial connective tissue. The pathognomonic lesion is the Aschoff body in the proliferative stage, which is present in 30% to 40% of biopsy samples from patients with acute rheumatic fever.

Carditis and Rheumatic Heart Disease The use of echocardiography has contributed much toward understanding the pathogenesis of valvular regurgitation in rheumatic carditis. At least initially, the regurgitation appears to result from geometric changes and stresses affecting the left ventricle rather than from the rheumatic process directly involving the valve leaflets.

Carditis and Rheumatic Heart Disease Acute rheumatic fever is also the predominant cause of mitral stenosis; approx. 25% of patients with rheumatic heart disease have pure mitral stenosis. Mitral stenosis is characterized by progressive thickening, fibrosis and calcification of the leaflets and chordae tendineae. The leaflets show fibrous obliteration and the mitral valve orifice becomes funnel- shaped, like a fish- mouth. This feature and the classic hockey-stick appearance of the anterior mitral leaflet in diastole are well seen on echocardiograms

Rheumatic Heart Diseases Heart -Pathology Rheumatic Heart Diseases ? cells pathognomonic