BACKGROUND: Several case reports and series have described myocardial infarctions (MIs) in patients hospitalized for thrombotic thrombocytopenic purpura (TTP). The exact magnitude and outcome of this complication are unknown. METHODS: Electronic medical records for patients admitted to Wake Forest University Baptist Medical Center were examined from 1996 to 2005. Those patients having a diagnosis of TTP during the hospitalization period were included in the analysis. Only patients' initial episodes of TTP were analyzed. Baseline cardiac and TTP risk factors were documented. Outcomes analyzed included MIs, arrhythmias, development of congestive heart failure and death. RESULTS: Eighty-five patients diagnosed with TTP were identified with 13 (15.3%) having MIs, as defined by an elevation of cardiac enzymes. Median troponin I value was 5.9 ng/mL (range 3.7-8.8 ng/mL). Twelve patients had non-ST segment elevation MIs and one had ST segment elevation. Two of 13 patients who had echocardiographic analysis had documented wall motion abnormalities. There was no difference between non-MI and MI patients in cardiac risk factors, prior cardiac events, history of thromboembolic disease or heart failure. There was no in-hospital mortality difference. CONCLUSION: MI is an important complication of TTP, identified in 15.3% of patients in our study. Routine cardiovascular evaluation with cardiac enzymes, electrocardiography, and telemetry is warranted in acute TTP patients. Appropriate intervention is yet to be determined.