A lot vs. Alot: 9 Grammatical Pitfalls
aortic stenosis n.
Pathological narrowing of the orifice of the aortic valve.
narrowing of the passage between the left lower chamber (ventricle) of the heart and the aorta, the principal artery of the systemic circulation. The defect is most often in the valve at the mouth of the aorta but may be just above or below the valve (supravalvular and subvalvular aortic stenosis, respectively). Aortic stenosis in a person younger than 20 years of age is usually congenital in origin. If it appears during middle age, it is most often the result of rheumatic heart disease. Aortic stenosis in elderly persons may be the result of degeneration of the valve with age. Most patients are male.