The heart pumps blood in one direction. To ensure that blood enters and leaves the heart in the correct direction, with no backflow, the heart has a set of leaflets, or valves — flaps that continually open and close. Heart valve disease results when a valve loses its ability to regulate blood flow properly.
Heart Valves: An Overview
The heart has four one-way valves:
- The tricuspid valve allows blood to pass from the right atrium to the right ventricle. The valve prevents blood from flowing back into the right atrium as the heart pumps.
- The pulmonary valve allows blood to pass into the pulmonary arteries; it prevents blood from flowing back into the right ventricle.
- The mitral valve allows oxygenated blood to flow from the lungs into the left ventricle. The valve prevents blood from flowing back into the left atrium.
- The aortic valve allows blood to pass from the left ventricle to the aorta, which transports blood to the rest of the body. This valve also prevents backflow of blood into the left ventricle.
On the right side of the heart:
On the left side of the heart:
Heart valve disease occurs when a valve doesn't work properly, by not opening or closing completely. This results in blood not moving through the heart's chambers as it should. To compensate, the heart muscle has to work harder to ensure that the appropriate amount of blood is circulated throughout the body. Heart valve disease can affect any of the heart's four valves.
Common Valve Disorders
The vast majority of valve repair and replacement procedures performed every year in the U.S. involve the mitral and aortic valves. These valves are located on left side of the heart, the side tasked with pumping oxygen-rich blood to the rest of the body. The left side therefore works much harder than the right side.
Generally speaking, valve disorders fall into these categories:
- Stenosis, or narrowing of the valve: Because the valve cannot open as widely as it should, it restricts blood flow. Narrowing is typically caused when valve leaflets thicken, stiffen or fuse together. It can be the result of scarring related to rheumatic fever, which is associated with strep throat or scarlet fever. Rheumatic fever is less common in the U.S., but is prevalent in developing nations. Stenosis also may be present at birth (congenital). Older adults may develop degenerative calcification (calcium buildup) of the aortic valves.
- Prolapse: Tissue buildup that thickens and enlarges valve flaps and strings that anchor the leaflets to the heart muscle. In effect, the valves cannot close tightly; they flop or bulge instead. Mitral valve prolapse is the most common heart valve disease. It occurs when mitral valve's two leaflets flop backward into the left atrium.
- Regurgitation: This occurs when blood leaks backward and is typically caused by prolapse.
It's possible for a patient to have both valvular stenosis and prolapse, in one or more valves, at the same time.
Causes of Heart Valve Disease
A patient can be born with heart valve disease or acquire it later in life.
- Heart valve disease that develops before birth is considered congenital. Congenital heart valve disease usually involves pulmonary or aortic valves that don't form properly. These valves may not have enough tissue flaps, may be the wrong size or shape, or may lack an opening through which blood can flow properly.
- Acquired heart valve disease develops over time, throughout one's life, due to wear and tear. This valve disease usually affects the aortic or mitral valve.
Symptoms of Heart Valve Disease
Many people have heart valve defects or disease but do not experience symptoms. The condition can remain the same throughout one's life, without causing problems. However, for many individuals, heart valve disease can gradually worsen until symptoms develop.
Symptoms of valve disease include chest pain or tightness, feeling faint, shortness of breath, fatigue, heart palpitations (fluttering heartbeat), irregular heartbeat (arrhythmia), and heart murmur.
As aortic and mitral valve stenosis develop, the muscles of the left ventricle must pump harder to compensate for inadequate blood flow. Muscle tissue becomes stiffer, resulting in chest pain. Blood may back up in the lungs as well, causing shortness of breath and fatigue.
The Importance of Treatment
While medicines cannot cure heart valve disease, they can help manage many related symptoms and problems. But if heart valve disease goes untreated, it can lead to heart failure, stroke, blood clots or cardiac arrest. Learn about heart valve repair and replacement at HonorHealth.