Regarding the correlation between the NSE levels and neurological complications following cardiac surgery, while NSE was reported to be a useful biomarker for brain damage [9, 10], Ishida et al. [11] stated that, in mediastinal surgery, since a significant amount of NSE is present in circulation, this mixes with the cardiotomy suction blood, which makes the use of NSE levels unreliable for measuring brain complications. The gene discussed is ENO2; the disease is complication.