A 26-year-old black woman, without risk factors for coronary artery disease, was admitted in the cardiology department of our institution for acute chest pain. Three months before admission, she had an episode of abdominal pain along with fever, thrombocytopenia (platelet count 23 000/mm 3 ), and hemolytic anemia (hemoglobin 5.1 g/dL).Thrombotic thrombocytopenic purpura was diagnosed with ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity of Ͻ5% and presence of anti-ADAMTS-13 antibody activity. 1 Severe thrombocytopenia (Ͻ50 000/mm 3 ) persisted despite intensive treatment with high-dose steroids, rituximab (anti-CD20 an- The online-only Data Supplement, which contains a movie, is available with this article at http://circ.ahajournals.org/cgi/content/full/ 118/7/e116/DC1.