Cardiac Troponin Elevation Predicts Mortality in Patients Undergoing Orthotopic Liver Transplantation

Introduction. While patients undergoing orthotopic liver transplantation (OLT) have high cardiovascular event rates, preoperative risk stratification may not necessarily predict those susceptible patients. Troponin T (TnT) may help predict patients at risk for cardiovascular complications. Methods. Consecutive patients undergoing OLT at Mayo Clinic in Florida between 1998 and 2010 who had TnT obtained within 10 days following surgery were included. Three groups were compared based on TnT level: (1) normal (TnT ？ng/mL), (2) intermediate (TnT 0.02–0.11？ng/mL), and (3) elevated (TnT ？ng/mL). Overall and cardiovascular mortality was assessed. Results. Of the 78 patients included, there was no difference in age, gender, severity of liver disease, and echocardiographic findings. Patients in the normal and intermediate TnT groups had a lower overall mortality rate (14.3% and 0%, resp.) when compared with those with elevated TnT (50%; ). Patients in the elevated TnT group had a cardiovascular mortality rate of 37.5% compared with 1.4% in the other groups combined ( ). The elevated TnT group had a much higher mortality rate when compared with those in the intermediate group ( ). Conclusion. TnT may accurately help risk stratify patients in the early postoperative setting to better predict cardiovascular complications. 1. Introduction Despite a standardized and comprehensive preoperative cardiovascular evaluation, the peri- and postoperative cardiovascular event rate is high in patients with end-stage liver disease undergoing orthotopic liver transplantation (OLT) [1–3]. In fact, cardiovascular mortality remains the third leading cause of death following OLT and is responsible for 12%–16% of all deaths [3]. Conventional stress testing and risk-factor assessment may be inadequate to fully detect the burden of coronary artery disease in this population [1–6]. Due to the excessive postoperative cardiovascular event rate, an additional tool beyond careful clinical evaluation and noninvasive cardiovascular imaging to aid risk assessment may be of value. Cardiac troponin is a contractile protein located within the myocyte which may be detected by sensitive assays in the setting of myocardial necrosis [7]. Several studies have suggested that troponin is valuable in patients with both acute and chronic liver failure prior to transplantation. Such studies have shown that an elevated troponin preoperatively is indicative of worse peri- and postoperative outcomes, yet none have studied the relevance of troponin elevation post-transplantation [1–6]. Mechanisms of troponin