Background: This study aims to determine the relationship between troponin levels and 30- and 90-day mortality rates in patients who applied to emergency service with paroxysmal supraventricular tachycardia. Materials and methods: The data of our study were obtained from the retrospective screening of the files of 321 patients who applied to the emergency department between 1 January 2015 and 31 December 2016 with International Classification of Diseases diagnosis with I47.1 (supraventricular tachycardia). Unstable patients, patients under 18 years, and patients with comorbidities that could increase troponin levels did not participate in the study. A total of 159 patients diagnosed with paroxysmal supraventricular tachycardia were included in the study. These patients’ files were examined, and their examination and anamnesis information at the time of admission to hospital, demographic characteristics, and applied treatments were analyzed. The 30- and 90-day mortality rates of the patients were examined. Results: The study was carried out with 159 patients. Troponin was positive in 25 (15.7%) cases, while it was negative in 134 (84.3%) cases. There was no significant difference between the two groups in terms of 30- and 90-day mortality rates. Coronary artery disease was found to be higher in patients with positive troponin than patients with negative troponin. Conclusion: No significant difference was found between patients with positive troponin values compared to patients with negative troponin values in terms of 30- and 90-day mortality rates. We believe that prospective observational studies or large-scale retrospective studies will better elucidate this issue.