Rheumatic Heart Disease

Rheumatic Heart Disease

Alfrin Antony Lecturer Department of pathology +919738286092

Definition:- Rheumatic heart disease is a chronic condition characterized by scaring and fibrosis of valves and layers of the heart secondary to rheumatic fever

Pathogenesis:Autoimmune mechanism has been proposed Attack of group ‘A’ beta hemolytic streptococci ↓ Pharyngitis ↓ Antibodies directed against the M proteins of certain strains of streptococci cross-react with tissue glycoprotein in the heart, joints and other tissues. ↓ (Heart) Edema of connective tissues and increased acid mucopolysaccharide in the ground substance. ↓ Accumulation of ground substance. ↓ Separation of collagen fibers. ↓ Collagen fibers become fragmented and disintegrated. ↓ Proliferation of cells (lymphocytes, plasma cells, a few neutrophils, cardiac histocytes (anitschkow cells) at the margin of the lesion ↓ Aschoff nodules (12 to 16 weeks) ↓ Anitschkow cells nodule becomes spindle shaped with diminished cytoplasm. ↓ AFTER YEARS Aschoff body becomes less cellular and collagenous tissue is increased ↓ Fibro collagenous scar ↓ Formation of chronic sequelae (endocardium , myocardium, pericardium)

Rheumatic pancardiditis 1. Rheumatic endocarditis (a).Rheumatic valvulitis (b).Rheumatic mural endocarditis 2. Rheumatic myocarditis 3. Rheumatic pericarditis 1(a).Rheumatic Valvulitis Grossly Acute 1.Thickening and loss of translucency of the valve leaflets 2.Gray brown, watery vegetations Chronic 1.Permanent deformity of on one or more valves (mitral or aortic) 2.”Fish mouth” or “button hole” 3.Thickening, shortening and fusion of chordae tendinae 1(b).Rheumatic mural endocarditis Grossly MacCallum’s patch:Lesions of endocardial surface in the posterior wall of the left atrium just above posterior leaflet of the mitral valve

2. Rheumatic Myocarditis Grossly Acute Left ventricular myocardium soft and flabby

Microscopically Acute 1.Edema 2.Cellular infiltration 3.Vegetations of fibrin Chronic 1.Thicken by fibrous tissue with hyalinization (Calcification rarely) 2.Thickened blood vessels with narrowed lumina

Microscopically MacCallum’s patch:a. Edema b. Fibrinoid changes in collagen c. Cellular infiltrate of lymphocytes d. Plasma cells e. Macrophages f. Anitschkow cells*

Microscopically

Acute Aschoff nodules are scattered (inter venticular septum, left ventricle and left atrium) Intermediate stage Intermediate stage Interstitial tissue of the myocardium shows In Aschoff:- Granuloma with central small foci of necrosis fibrinoid necrosis and surrounded by palisade of anitschkow cells Late stage Late stage Foci of aschoff bodies are visible Aschoffs bodies are replaced by small fibrous scars

3. Rheumatic Pericarditis Grossly chronic a). Deposition of fibrous exudates (Loss of normal shiny pericardial surface) b). Accumulation of fibrous exudates in the pericardial sac (“Bread and butter” appearance) c). Chronic adhesive pericarditis

Microscopically chronic a). Fibrosis aschoff bodies on the surfaces b). Infiltrated sub serosal connective tissue

c). Adhesions between visceral and parietal surfaces Extracardiac Lesions  Polyarthritis  Subcutaneous nodules  Erythema marginatum  Rheumatic arteritis  Chorea minor  Rheumatic pneumonitis pleuritis ANTOBODIES AGAINST Beta-Haemolytic streptococci group A  Anti-streptolysin O (ASO)  Anti-streptokinase  Anti-streptohyaluronidase  Anti DNA ase B

Diagnosing criteria Diagnosed by Jones Criteria: Either two of the major manifestations or one major and two minor manifestations. JONES CRITERIA MAJOR CRITERIA 1.Carditis 2.Poly arthritis 3.Chorea:- a neurologic disorder with involuntary purposeless rapid movements. 4.Erythema Marginatum

MINOR CRITEIA 1.Fever 2.Arthralgia 3.Previous History of RF 4.Increased a. E.S.R

5.Subcutaneous Nodules

b. C-Reactive Protein c. Leucocytosis 5.Prolonged PR interval

Complications • Severe mitral stenosis progresses to left atrial hypertrophy and dilatation, • Mural thrombosis, • Pulmonary congestion, • Pulmonary vascular sclerosis and then right ventricular hypertrophy. • The left ventricle is normal is isolated pure mitral stenosis. Other complications of chronic RHD include • heart failure, • Arrhythmias particularly AF in case of M.S, • Thrombo embolic complications and infective endocarditis. • The long term prognosis is highly variable • Rx- Surgical replacement of diseased valves with prosthetic device *anitschkow cell: are the cardiac histocytes present in small numbers in the normal heart. The nuclei are vesicular and contain prominent central chromatin mass which in longitudinal section appears “serrated” or “caterpillar” like and in cross section it look like an “owl’s eye” **Aschoff bodies: are spheroidal or fusiform distinct microscopic structures occurring in the intestitium of the heart in RHD.(it contains almost four anitschkow cells )