Paper II
Question
Describe the autopsy findings in lungs and heart in a 40-year-old male with longstanding rheumatic heart disease with mitral stenosis
Answer
Heart findings
Gross
- Mitral valve leaflets show thickening, fibrosis, and fusion of the commissures, producing a characteristic “fish-mouth” or “buttonhole” deformity of the stenotic mitral valve
- Chordae tendineae are thickened, fused, and shortened
- Left atrial dilatation and hypertrophy (due to increased pressure load from the stenotic valve) — may show a left atrial appendage thrombus (predisposing to systemic embolism, particularly with associated atrial fibrillation)
- Right ventricular hypertrophy (secondary to pulmonary hypertension resulting from chronically elevated left atrial pressure transmitted backward)
Microscopic
- Fibrosis and neovascularization of the valve leaflets, with loss of normal valve architecture
- Aschoff bodies may be seen in cases with ongoing rheumatic activity (though typically absent in longstanding “burnt-out” chronic disease) — foci of fibrinoid necrosis surrounded by lymphocytes, plasma cells, and Anitschkow cells (activated macrophages with caterpillar-shaped nuclei)
Lung findings
Gross
- Chronic passive venous congestion — heavy, firm, brown-indurated lungs (“brown induration”) due to longstanding elevated pulmonary venous pressure
- Pulmonary oedema may be present in acute decompensation
Microscopic
- Thickened, fibrotic alveolar septa
- Congested alveolar capillaries
- Haemosiderin-laden alveolar macrophages (“heart failure cells”) — from phagocytosis of red cells that have extravasated into alveoli due to chronic capillary congestion
- Chronic changes may progress to secondary pulmonary hypertension with medial hypertrophy of pulmonary arterioles