Erythema multiforme (EM) is a skin reaction that comes from an infection or another trigger. EM is a type of allergic reaction. In most cases, it occurs in response to an infection. In rare cases, it is caused by certain medicines or body-wide (systemic) illness. Infections that may lead to EM include:
1 Heart attack. A heart attack can damage the area of the heart muscle that supports the mitral valve, affecting the function of the valve. If the damage is extensive enough, a heart attack can cause sudden and severe mitral valve regurgitation.  Abnormality of the heart muscle (cardiomyopathy).
Definition. Aortic valve regurgitation â or aortic regurgitation â is a condition that occurs when your heart's aortic valve doesn't close tightly. Aortic valve regurgitation allows some of the blood that was just pumped out of your heart's main pumping chamber (left ventricle) to leak back into it.efinition. Aortic valve regurgitation â or aortic regurgitation â is a condition that occurs when your heart's aortic valve doesn't close tightly. Aortic valve regurgitation allows some of the blood that was just pumped out of your heart's main pumping chamber (left ventricle) to leak back into it.