Postoperative Cardiac Troponin I Thresholds Associated with One-Year Cardiac Mortality after Adult Cardiac Surgery: An Attempt to link Risk Stratification with Management Stratification in an Observational Study

Abstract Background Cardiac troponin (cTn) concentrations are routinely measured in some centers after cardiac surgery as part of risk stratification, but there are no data on how “increased cTn concentrations” could change patients’ management. Objectives To estimate relevant cTnI thresholds and identify potential interventions (additional monitoring/therapeutic interventions) that could be part of management changes of patients with cTnI > relevant thresholds. Design Retrospective single-center observational study. Setting Bichat-Claude Bernard Hospital, Paris, France, between January 1, 2009 and December 31, 2012. Patients Consecutive adult patients undergoing cardiac surgery. Main outcome measures cTnI was measured on the 20 th postoperative hour. Causes of death and possible interventions were determined by individual medical records analysis. cTnI thresholds for 1-year cardiac mortality with a specificity > 80% were calculated. Results We analyzed 3,228 procedures: 129 deaths occurred (4%) out of which 83 (2.6%) were cardiac deaths . Thresholds cTnI values were 4.2 µg/L for coronary artery bypass grafting (CABG) (95% CI, 3.9-4.5) and 10.7 µg/l for non-CABG (95% CI, 10.0-11.3). In multivariable analysis, the EuroSCORE II (OR 1.1; 95% CI, 1.06-1.13; P thresholds (OR 5.62; 95 % CI, 3.37-9.37; P cardiac deaths (64%) had a cTnI > thresholds and an intervention was deemed possible in 47 out of 53 (89%) of them (mostly patients with mild postoperative cardiac dysfunction). For non-cardiac deaths, 28% had a cTnI > thresholds and no interventions were deemed possible. Conclusions In an attempt to evolve from risk- to management stratification, our results identified a subgroup of patients with mild cardiac dysfunction and a cTnI > thresholds who could be the target for interventions in future validation studies concerning changes in patients ‘management. Trial registration ClinicalTrials.gov ID: NCT03393169