Troponin T clearance via continuous renal replacement therapies in the ICU

Purpose The aim of this study was to compare the removal of cardiac troponin T via continuous venovenous haemofiltration (CVVH), continuous venovenous haemodialysis (CVVHD) and continuous venovenous haemodiafiltration (CVVHDF) as a function of circulating blood troponin T levels in critically ill patients. Methods This was a single-centre, prospective observational study conducted at Tallaght University Hospital (Dublin, Ireland). Adult patients admitted to ICU and commenced on continuous renal replacement therapy (CRRT) were included. All patients required a troponin T level > 50 ng/L. All patients were required to have commenced CRRT > 4 h prior to first sample. The aim was to take three serum samples per patient every 24 h, over a total of 72 h, with simultaneous sampling of the waste effluent for troponin T. Our primary outcome measure was estimated troponin T clearance according to CRRT modality. Results We found no significant difference in estimated troponin T clearance according to CRRT modality (overall median troponin T clearance of 2.6 ml/kg/h). As a secondary outcome, it was noted that the percentage of troponin T clearance was statistically significantly higher for CVVH compared to CVVHD and CVVHDF (16% vs. 15% vs. 10%, respectively; p = 0.002). Conclusions No significant difference in estimated troponin T clearance was found according to CRRT modality. Our results show that clearance of troponin T on CRRT is generally small across all modalities and that ongoing treatment with CRRT is unlikely to substantially impact interpretation and tracking of troponin T results in patients with concern for acute coronary syndrome.