Patients with end-stage renal disease commonly develop acute coronary syndromes (ACS). Little is known about the natural history of ACS in patients receiving dialysis. We evaluated the presentation, management, and outcomes of patients with ACS who were receiving dialysis before presentation for an ACS and were enrolled in the Global Registry of Acute Coronary Events (GRACE) at 123 hospitals in 14 countries from 1999 to 2007. Of 55,189 patients, 579 were required dialysis at presentation. Non-ST-segment elevation myocardial infarction was the most common ACS presentation in patients receiving dialysis, occurring in 50% (290 of 579) of patients versus 33% (17,955 of 54,610) of those not receiving dialysis. Patients receiving dialysis had greater in-hospital mortality rates (12% vs 4.8%; p