Heart failure is the most common and potentially the most life-threatening complication of aortic valve stenosis.
Aortic valve stenosis causes a buildup of pressure inside the heart chamber that pumps blood to the body (the left ventricle). The ventricle compensates for the pressure by thickening and pumping harder to force blood through the narrowed valve.
Your heart can work hard for a long time to compensate for the narrowed aortic valve. In fact, your heart compensates so well that you may not feel any symptoms of stenosis for many years, even decades. But eventually the valve becomes too narrow and your heart can no longer keep up. The effort of pumping so hard under pressure year after year will wear out your heart muscle prematurely.
When the heart wears out, a person starts to have symptoms like chest pain or pressure, dizziness, or shortness of breath. Symptoms happen because the left ventricle can no longer compensate and the pressure begins to stretch (dilate) the heart muscle. Eventually the heart loses its ability to pump enough blood to meet the body's needs.
As your heart loses its ability to pump blood to your body, your heart also cannot supply enough oxygen-rich blood to its own muscle. Your heart muscle starts to suffer from lack of oxygen, and heart failure continues to progress.
If you have heart failure, you might also get atrial fibrillation, a type of irregular heartbeat. Because heart failure causes the heart to stretch out of shape, it changes the electrical system of the heart. And this change can lead to atrial fibrillation.
Endocarditis is an infection of the heart's valves or its inner lining (endocardium). It is most common in people who have a damaged, diseased, or artificial heart valve.
If you have a problem with your heart that affects normal blood flow through the heart, it is more likely that bacteria or fungi will attach to heart tissue. This puts you at a higher risk for endocarditis. If you have certain heart conditions, getting endocarditis is even more dangerous for you. These heart conditions include having an artificial heart valve, having a congenital heart defect, having had endocarditis in the past, and having a heart valve problem after a heart transplant.
Mitral valve problems
The aortic and mitral valves are very close together in the heart. Problems can happen in both valves at the same time. When this happens, the heart cannot pump blood as well as it can when there are no problems in the valves.
When aortic and mitral valve problems happen together, it might be hard for your doctor to know that both valves are affected. 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.
What happens if you have mitral regurgitation and aortic stenosis?
Mitral valve 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.
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.
Having both valve problems can cause problems like heart failure to happen sooner.
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 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, your heart cannot pump blood normally.
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. Because the mitral valve is narrow, the left atrium cannot pump a normal amount of blood into the left ventricle, making it even harder for the left ventricle to pump enough blood through the narrowed aortic valve.
Aortic valve regurgitation
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 big enough to require valve replacement, even though neither problem alone would have required surgery. Multiple valve problems are most serious when both valve problems are moderate to severe. But aortic stenosis can actually make other valve problems worse over time.
Sudden cardiac death occurs when the heart abruptly ceases to function from one or more existing problems. Aortic valve replacement surgery lowers the risk of sudden death from aortic stenosis. Sudden death almost never occurs in people who do not yet have symptoms of aortic valve stenosis.
In general, sudden death in people who have aortic valve stenosis is closely associated with heart failure. Also, sudden death can occur when severe stenosis and advancing heart failure cause an irregular heartbeat.