Systemic Lupus Erythematosus(SLE) is a multisystem autoimmune disease with variable presentations. A proposed mechanism for the etiology of SLE involves the development of autoantibodies that result from a defect in apoptosis. The specific defect involves the “find-me” (adenosine triphosphate [ATP]/uridine triphosphate [UTP]) or “eat-me” (phosphatidylserine) signals activated upon release of red cell nuclei. In the absence of apoptosis, the nuclei break down, causing inflammation and contributing to the development of autoimmunity. Many signs and symptoms of SLE are caused by either circulating immune complexes or direct effects of antibodies on cells. A genetic predisposition for SLE exists, and the concordance rate in monozygotic twins is between 25% and 70%. If a mother has SLE, her daughter’s risk of developing the disease is 1:40, and her son’s risk is 1:250. The course of SLE consists of intermittent remissions punctuated by disease flares, and organ damage often progresses over time. Pericarditis is the most frequent cardiac manifestation; it can be documented by ECG, auscultation of a friction rub, or evidence of pericardial effusion. It usually responds to anti-inflammatory therapy and infrequently leads to tamponade. More serious cardiac manifestations are myocarditis and fibrinous endocarditis of Libman-Sacks. The endocardial involvement can lead to valvular insufficiencies, most commonly of the mitral or aortic valves, or embolic events. It has not been proven that glucocorticoid or other immunosuppressive therapies improve lupus myocarditis or endocarditis. Still, it is usual practice to administer a trial of high-dose steroids and appropriate supportive treatment for heart failure, arrhythmia, or embolic events. As discussed above, patients with SLE are at increased risk for myocardial infarction, usually due to accelerated atherosclerosis, which probably results from immune attack, chronic inflammation, and chronic oxidative damage to arteries.