Serum Cardiac Troponin I Concentrations in Dogs with Systemic Inflammatory Response Syndrome

Background: Myocardial injury can be detected by cardiac troponin I ( cTnI) concentration, which appears to be a predictor of short- term death in critically ill patients. It is unknown if the best prognostic indicator of short- term survival is cTnI measurement at admission or at later time points. Hypothesis/ Objectives: Measuring cTnI with a high- sensitivity ( HS) test at different time points after admission may be a better short- term prognostic indicator than a single cTnI measurement at admission in dogs with systemic inflammatory response syndrome ( SIRS). Animals: Prospective, observational clinical study of 60 dogs with SIRS. Methods: Cardiac troponin I concentration was measured in 133 serum samples, collected at days 1, 2, 3, and 5. Additionally, the acute patient physiologic and laboratory evaluation ( APPLE) fast score was evaluated at admission. Prognostic capabilities of cTnI measurement and APPLE fast score for 28- day mortality were assessed by receiver operating characteristic curve analysis. Results: Forty- one dogs with SIRS that survived 28 days had significantly lower serum cTnI concentrations at admission ( median, 0.09 ng/ mL; P =.004) and at the peak time point ( median, 0.23 ng/ mL; P =.01) compared to 19 nonsurvivors ( median at admission, 0.63 ng/ mL; median at peak, 1.22 ng/ mL). Area under the curve to predict survival, using cTnI was similar at admission ( 0.732) and at peak ( 0.708), and was 0.754 for the APPLE fast score. Conclusions and Clinical Importance: Increased cTnI concentration in dogs with SIRS is associated with poor outcome. Daily follow- up measurement of cTnI concentration provides no additional prognostic information for short- term mortality.