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.