Systemic lupus erythematosus (SLE) is a multisystem disorder with numerous potential adverse effects on the cardiovascular system. These complications likely develop in most patients with SLE at some time during the course of their disease, in part due to the decreased mortality associated with SLE as a result of modem medical management. Conduction disturbances have been reported in the literature to occur primarily from the progression of SLE and secondarily from pharmacotherapy used to treat SLE and may first be evident on the electrocardiogram in the emergency department (ED) setting. Electrocardiogram abnormalities such as borderline first-degree heart block may be clues to more significant cardiac disease brought upon by years of chronic inflammation, myocarditis, vasculitis, and fibrosis that are often the result of longstanding autoimmune disease. It is essential that patients with autoimmune disease be screened carefully in the ED setting for underlying myocardial disease, particularly given the increased potential for atherosclerosis, ischemia, arrhythmias, and myocardial conduction defects in these patients.