C5 and myocardial infarction: Eculizumab is a monoclonal antibody that binds to C5 and inhibits its breakdown to C5a and C5b and therefore prevents subsequent formation of the membrane attack complex (MAC).28,29 The feared complications of hemodialysis in complement-related aHUS can also be prevented by placing the patient on eculizumab during the treatment sessions.30 Since myocardial infarction and heart failure are life-threatening complications, early clinical suspicion leading to prompt diagnosis and initiation of therapy are of utmost importance to improve survival and long-term prognosis.