Serum butyrylcholinesterase predicts survival after extracorporeal membrane oxygenation after cardiovascular surgery

INTRODUCTION Risk stratification in patients undergoing extracorporeal membrane oxygenation (ECMO) support after cardiovascular surgery remains challenging, because data on specific outcome predictors are limited. Serum butyrylcholinesterase demonstrated a strong inverse association with all-cause and cardiovascular mortality in non-critically ill patients. We therefore evaluated the predictive value of preoperative serum butyrylcholinesterase levels in patients undergoing venoarterial ECMO support after cardiovascular surgery. METHODS We prospectively included 191 patients undergoing venoarterial ECMO therapy after cardiovascular surgery at a university-affiliated tertiary care center in our registry. RESULTS All-cause and cardiovascular mortality were defined as primary study end points. During a median follow-up time of 51 months (IQR, 34 to 71) corresponding to 4,197 overall months of follow-up, 65% of patients died. Cox proportional hazard regression analysis revealed a significant and independent inverse association between higher butyrylcholinesterase levels and all-cause mortality with an adjusted hazard ratio (HR) of 0.44 (95% CI, 0.25 to 0.78; P = 0.005), as well as cardiovascular mortality, with an adjusted HR of 0.38 (95% CI, 0.21 to 0.70; P = 0.002), comparing the third with the first tertile. Survival rates were higher in patients within the third tertile of butyrylcholinesterase compared with patients within the first tertile at 30 days (68% versus 44%) as well as at 6 years (47% versus 21%). CONCLUSIONS The current study revealed serum butyrylcholinesterase as a strong and independent inverse predictor of all-cause and cardiovascular mortality in patients undergoing venoarterial ECMO therapy after cardiovascular surgery. These findings advance the limited knowledge on risk stratification in patients undergoing ECMO support and represent a valuable addition for a comprehensive decision making before ECMO implantation.