This 49 year old woman collapsed at home. She was noted to be in acute pulmonary oedema on admission to the emergency department, but despite treatment, she died 2 hours after admission.
The specimen is the superior half of the heart. The left atrium and the mitral valve are displayed. The left atrium is markedly dilated. The mitral valve cusps are deformed, opaque and stenotic. The residual mitral valve opening is reduced in area and has a "fish mouth" appearance. It is difficult to assess the left ventricle from this specimen but there may be a degree of left ventricular hypertrophy.
Heart: Mitral stenosis; ? mitral incompetence.
What is the pathogenesis of acute pulmonary oedema in mitral stenosis? Is the oedema fluid in the alveolar spaces a transudate or an exudate? What is the likely pathogenesis of the mitral stenosis in this patient?