pulmonary valve stenosis

In cases of subaortic stenosis, the aortic valve is mostly normal and tricuspid. In some cases, the leaflets are slightly thickened, or there may be mild aortic regurgitation. A few patients may also have bicuspid aortic valve stenosis. The left ventricular myocardium shows severe concentric hypertrophy, and subendocardial insufficient blood supply may lead to myocardial fibrosis. Sometimes the degree of hypertrophy of the interventricular septum is more pronounced than that of the posterior wall of the left ventricle, which can easily be confused with hypertrophic obstructive cardiomyopathy. Approximately one-third of cases of subaortic fibrotic stenosis are accompanied by other congenital cardiovascular malformations, commonly including ventricular septal defect, interruption of the aortic arch, patent ductus arteriosus, tetralogy of Fallot, atrial septal defect, pulmonary valve stenosis, or right ventricular outflow tract stenosis.