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).
Secondary regurgitation means another heart problem causes the valve to not close tightly. The anatomy of the valve is typically normal. The heart problem, such as heart failure, affects the heart muscle, and this causes regurgitation. Acute mitral valve regurgitation develops quickly and can be life