Mitral valve stenosis is usually caused by rheumatic fever. In this condition, the two leaflets of the mitral valve gradually fuse together, making it difficult for the blood traveling into the left atrium from the lungs to pass through the mitral valve and into the left ventricle. As this condition becomes more severe, shortness of breath devel ops because blood backs up Into the lungs. Fatigue is also a common symptom. Also, some babies are born with an abnormally narrowed mitral valve
In some cases, the patient may cough up blood. (However, there are many other causes of coughing up blood [hemoptysis].) Depending on the degree of mitral valve stenosis, some form of intervention may be necessary. This might involve using a balloon catheter to dilate the stenotic mitral valve and could also mean heart surgery.
Mitral valve incompetence, which is also referred to as mitral valve regurgitation or insufficiency, occurs when the two leaflets of the mitral valve no longer meet each other when the valve is closed. Because the leaflets do not meet, some of the blood that should be ejected into the aorta is squeezed through the faulty mitral
valve backwards into the left atrium as the left ventricle contracts. The resulting higher pressure in the left atrium sends blood backwards into the lungs.
This condition can cause shortness of breath and fatigue. The heart also has to work harder because some of the blood that's being pumped is going backwards. As a result, the left ventricle will dilate and begin to fail, adding to the shortness of breath. Patients also have swollen ankles. If this problem becomes severe, heart surgery will most likely be required.
Another condition is called myxoid degeneration, in which some of the tissues in the heart are weakened, and the valve is prone to incompetence. This condition can affect varying parts of the mitral valve. For example, the chordae, which attach the valve to the underlying muscles, can rupture (Fig. 10.4). Likewise, the papillary muscles can rupture. Papillary muscle rupture is usually related to a heart attack. This condition requires emergency heart surgery.
As with the aortic valve, the mitral valve may deform so that it obstructs the flow of blood into the left ventricle and prevents it from closing normally because the two mitral leaflets no longer touch each other. In this condition, the valve is narrowed and incompetent, sending some of the blood back through the deformed valve. Depending on the severity of this problem, heart surgery may be required.
Was this article helpful?