Peri-operative troponin monitoring using a prototype high-sensitivity cardiac troponin I (hs-cTnI) assay: comparisons with hs-cTnT and contemporary cTnI assays.

Background Non-cardiac surgery is associated with major vascular complications and higher incidences of elevated plasma troponin (cTn) concentration. Goal-directed therapy (GDT) is a stroke volume (SV)-guided approach to intravenous (IV) fluid therapy that improves tissue perfusion, oxygenation and reduces post-operative complications. In patients undergoing major gastro-intestinal surgery, we compared high sensitive and contemporary troponin assays and correlated results with patient outcome. Methods Patients (n=135) were randomized to receive IV fluid, guided by either the central venous pressure (CVP group, n=45) or SV ( dopexamine inotrope, n=45 per group). Serum was obtained pre- and post-operatively (0, 8 and 24h) for troponin analysis by a prototype hs-cTnI assay (Abbott Laboratories), hs-cTnT (Roche Diagnostics) and contemporary cTnI (Beckman Coulter) assays. Results All troponin measurements were increased (P0.05) post-operatively but there was no difference (P>0.05) amongst treatments. Post-operative increases were reported more frequently (P0.05) and earlier with hs-cTnI. Temporal increases (P0.05) were reported in patients with and without complications for hs-cTnI/T assays but only in the complications group for cTnI measurements. Elevations 99th centile occurred most often (P0.05) for hs-cTnT measurements but with similar frequency for both outcome groups (all assays). Only the hs-cTnI assay showed an increased relative risk of mortality (P0.05) for elevations 99th centile Conclusions Our study may suggest a possible preference for the hs-cTnI assay in the peri-operative setting; however, our findings should be verified for larger cohort studies where emerging reference range data is incorporated for improving risk prediction with hs-cTn assays.