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).
Any condition that damages the aortic valve can cause aortic valve regurgitation. Common causes of chronic valve problems include: 1  Being born with a bicuspid aortic valve or a damaged aortic valve. 2  Aging. 3  Enlargement of the aorta because of high blood pressure or hardening of the arteries. 4  Rheumatic fever.