Aortic valve stenosis and other valve problems
Rheumatic fever and sclerosis (hardening and narrowing) can cause aortic valve stenosis to occur along with other valve problems, particularly those that affect the mitral valve, which regulates blood flow between the left atrium and the left ventricle.
When aortic valve stenosis causes heart failure, blood can back up into the right side of the heart and can cause problems with the pulmonic and tricuspid valves, although these are quite rare. Most commonly, problems with the aortic valve occur along with mitral valve regurgitation (a leaky mitral valve). Because the aortic and mitral valves flank the left ventricle and are involved in regulating blood flow to the rest of the body, one valve would affect the functioning of the other.
Multivalvular involvement is caused most frequently by rheumatic fever, and a variety of syndromes can be produced by different combinations of valvular abnormalities. Different conditions may affect each valve, such as an infection on the aortic valve and mitral valve regurgitation.
One valve problem can "mask" another. When blood arrives from your lungs, it enters your left atrium, passes through the mitral valve into your left ventricle, and then gets pumped out through your aortic valve. Because the blood passes through the mitral valve first, the problem with your mitral valve will typically be more prominent than aortic stenosis, essentially because it is "upstream." In fact, the problem with your mitral valve may actually "mask" your aortic stenosis, making it difficult for your doctor to detect.
What happens if you have mitral regurgitation and aortic stenosis?
Mitral regurgitation and aortic stenosis together form a potentially dangerous combination, although it is relatively rare for the two conditions to occur at the same time. When they do occur together, it is typically as a complication of rheumatic fever.
Mitral regurgitation refers to the leaking of blood from the left ventricle back through the mitral valve because of improper or incomplete closure of the valve. If the mitral valve is leaking, when the left ventricle contracts it will force blood backward into the left atrium, making it even harder for the ventricle to pump enough blood forward through the narrowed aortic valve. This speeds up the development of serious complications by accelerating:
- Overfilling of the left atrium, which stretches out (dilates) the heart muscle and causes an irregular heartbeat (atrial fibrillation).
- Backup of blood behind the left ventricle, leading to pulmonary hypertension, pulmonary edema, and right-sided heart failure.
- Deterioration of the left ventricle's ability to pump enough blood out to the body, leading to heart failure.
In addition, atrial fibrillation can prevent the left atrium from providing a "boost" of blood that helps supply the left ventricle with enough blood to pump.
Severe aortic stenosis can cause mitral regurgitation or make it worse. As the left ventricle begins to tire from the effort of pumping blood through the narrowed aortic valve, eventually the pressure overload in the ventricle begins to stretch out the heart muscle. This stretches the base of the mitral valve, preventing the valve from closing properly and causing regurgitation.
What happens if you have mitral stenosis and aortic stenosis?
Mitral valve stenosis and aortic valve stenosis almost always occur together as a complication of rheumatic fever. Mitral stenosis is a narrowing of the mitral valve, which restricts the flow of blood from your left atrium into your left ventricle. If you have mitral stenosis along with aortic stenosis, the two conditions can have a significant effect on the health of your left ventricle.
Essentially, your mitral stenosis restricts the flow of blood into your left ventricle and your aortic stenosis restricts the flow of blood out of your ventricle, causing the ventricle itself to become small and stiff, with thickened walls (hypertrophy). Because the mitral valve is narrow, the left atrium cannot pump a sufficient "boost" of blood into the left ventricle, making it even harder for the left ventricle to pump enough blood through the narrowed aortic valve.
What happens if you have aortic regurgitation and aortic stenosis?
Aortic regurgitation occurs when the aortic valve does not close properly and blood leaks back into the left ventricle. When aortic stenosis and regurgitation occur together, the effect of one of the two problems is usually more pronounced. If aortic stenosis is the dominant problem, it is similar to having aortic stenosis alone. If aortic regurgitation is the dominant problem, then it is like having aortic regurgitation alone.
The one exception is that if both problems are severe enough to affect the left ventricle, the effect may be significant enough to require valve replacement, even though neither problem alone would have required surgery. It is important to note that multiple valve problems are most serious when both valve problems are moderate to severe. However, aortic stenosis can actually make other valve problems worse over time.
| Author: | Douglas Dana Robin Parks, MS | Last Updated: January 22, 2008 |
| Medical Review: | E. Gregory Thompson, MD - Internal Medicine George Philippides, MD - Cardiology Andrew Swan, MD, CCFP, FCFP - Family Medicine | |
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