Paroxysmal supraventricular tachycardia (PSVT), a common dysrhythmia seen in the emergency department (ED), is usually managed without difficulty and with a favorable prognosis. Serum cardiac troponin I (cTnI) testing provides important risk stratification information in certain patients; its use in PSVT patients, however, has not been explored. A retrospective review of consecutive adult ED PSVT patients seen for 21 months was performed. Fifty-four PSVT patients were identified on the basis of International Classification of Disease, Ninth Edition codes and the ED patient log at a university hospital. Three patients were excluded for incorrect rhythm, leaving 51 who were included in data analysis. Thirty-eight patients had at least one serum cTnI value measured. Of those, 11 had a positive result, defined as serum cTnI of more than 0.02 ng/dL. Thirty-day outcomes for these patients were evaluated and showed one ED return, no PSVT recurrences, and no deaths at our regional hospital. In this sample, serum cTnI testing did not identify PSVT patients at risk for poor outcome. Further consideration of the use of this testing modality in the PSVT patient population is recommended. © 2011 Elsevier Inc. All rights reserved.