site logo

Aortic Stenosis

Categories: Uncategorized
Sources: Disturbances Of The Heart

Aortic narrowing or stenosis is a frequent occurrence in the aged

and in arteriosclerosis when the aorta is involved. It is not a

frequent single lesion in the young. If it occurs in children or

young adults, it is likely to be combined with aortic regurgitation,

meaning that the valve hay been seriously injured by an

endocarditis.



The first effect of this narrowing is to cause hypertrophy of the
/> left ventricle, and as long as this ventricle is able to force the

blood through the narrowed opening at the aortic valve, the general

circulation is perfect. Nature again steps in to cause such a heart

to heat deliberately, allowing time for the contracting ventricle to

force the blood through the narrowed orifice. The blood pressure may

be sufficient, or even increased if arteriosclerosis is present,

although the rise of the sphygmograph tracing is not so high as

normal. If the pressure in the aorta is sufficient from the amount

of blood forced into it, the coronary arteries receive enough blood

to keep up the nutrition of the heart muscle. Sooner or later,

however, the left ventricle will become weakened, especially when

there is arteriosclerosis or other hypertension, and chronic

endocarditis and fatty degeneration result. If the left ventricle

becomes sufficiently weakened or dilated, the same damming back of

the blood through the lungs and right heart occurs, and more or less

serious signs of broken compensation develop. The main danger,

however, with a heart with this lesion, occurring coincidently with

arteriosclerosis, is a progressive chronic myocarditis.



More

;