Dx Dialogues: How does aortic stenosis impact valve function?

Aortic stenosis is a progressive disease; there is no medication to slow the progression. It's a mechanical problem that requires a mechanical solution.

Transcript

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Aortic stenosis is a progressive disease. There is no medication to slow the progression. And it is a mechanical problem that

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requires a mechanical solution. [MELLOW MUSIC] Hi, I am Kendra Grubb.

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I am the surgical director of the Structural Heart and Valve Center at Emory University. I am an adult cardiac surgeon, which

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means that by the combination of those two titles, I do traditional open heart surgery as well as the newer

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technologies using catheters and wires in order to implant new valves in the heart without opening the breastbone.

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Aortic stenosis is tightening of the main outflow valve of the heart. Aortic valve is the gatekeeper to the left ventricle.

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Every time the ventricle pumps, the valve is supposed to open widely and allow blood to flow to the coronary arteries and the carotids

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and then the rest of the body. Well, with aortic stenosis, that valve starts to degenerate and calcify and the opening becomes narrow.

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Over time, the ventricle suffers myocardial damage from the extra pressure caused by the gradient

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across the valve. Of course, aortic stenosis is a progressive disease. There is no medication to slow the progression.

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And it is a mechanical problem that requires a mechanical solution. Aortic stenosis is actually calcification

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of the valve leaflets and the valvular apparatus. So the valve sits in the aorta and is supposed to open widely

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about 2 and 1/2 centimeters approximately every time the heart beats. And over time, as those leaflets start to thicken and calcify,

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the valve opening narrows. And as that progressive narrowing occurs,

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there's a back pressure into the ventricle. And so the heart starts to have changes which

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we consider myocardial damage. At first, the heart thickens. Just like if you were to go to the gym and lift weights,

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your muscles would thicken, the heart is a muscle just like any other muscle. But there's a limit to how much the heart can hypertrophy

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and when it can no longer accommodate the pressure that is needed to open the stuck valve.

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Then the heart starts to dilate. Over time, we'll see problems with the mitral valve, another left-sided valve, and eventually, you

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can have myocardial damage that extends to the right side and includes right ventricular failure, pulmonary hypertension,

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and eventually tricuspid regurgitation, all from this backflow through the system. [AUDIO LOGO]