RESUMO
BACKGROUND AND OBJECTIVES: Diagnosis of acute myocardial injury with biomarkers is difficult in patients with advanced renal failure. Circulating microRNAs are promising new biomarkers of myocardial injury. It is unknown whether levels of microRNAs are affected in patients undergoing hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: High-sensitivity cardiac troponin T (hsTnT) and cardiac-enriched miR-499 were measured in 41 patients with ESRD undergoing hemodialysis and 41 controls. RESULTS: Levels of hsTnT and miR-499 were highly elevated in patients with ESRD compared with controls (>80-fold increase; P<0.001). Among patients with ESRD, 98% had positive hsTnT levels and 46% had positive miR-499 levels. Levels of troponins were not affected by hemodialysis. However, miR-499 levels were decreased after hemodialysis (6.5-fold decrease; P=0.002). CONCLUSIONS: Both miR-499 and troponins are elevated in patients with advanced renal failure. However, whereas levels of troponins are unaffected by hemodialysis, this is not the case for miR-499. Therefore, these observations mitigate the potential of miR-499 as a marker of myocardial injury in patients with ESRD.