MP2034 - Congenital pulmonary stenosis

The specimen is the child‘s heart. View from the left side and note the pulmonary artery has been opened to display the upper surface of the pulmonary valve. This abnormal valve consists of a thickened conical diaphragm, with an opening 2 mm in diameter at the apex. The opened pulmonary artery has a large post-stenotic dilatation. There is right-sided cardiac enlargement due to marked dilatation of the right atrium and right auricle (opened), and right ventricular hypertrophy (the wall has been cut in two places [one penetrating, one one not] to expose the hypertrophied myocardium).