The incidence of cognitive decline occurs in 53% of patients after cardiac surgery. Causes of POCD can be various: age, duration of cardiac bypass, medicaments and many others. The aim of this study is to determine factors causing postoperative cognitive dysfunction (POCD) and to identify which of them are most important

Prospective case-control study included patients undergoing cardiac at Clinic of Cardiac, Vascular and Thoracic Surgery, Lithuanian University of Health Sciences. Inclusion criteria is: 1) cardiac output > 35%; 2) no agents affecting central nervous system; 3) no neuropathology; 5) no multiple organ dysfunction. Patients will have to perform mini mental state examination (MMSE), Trial making, addenbrooke tests before and 7 days after surgery. Brain biomarkers glial fibrillary acid protein (GFAP) and neurofilaments will be taken after induction, 24 and 48 hours after surgery. Transcranial Doppler will be performed to evaluate a.cerebri media blood flow speed during surgery.

After these test, the investigators are going to examine data about patient and operation, recognize factors causing POCD and identify the most important of them.

Inclusion Criteria:

• Coronary artery bypass grafting or/and heart valve surgery;
• Patients age>18years
• Cardiac output >35%

Exclusion Criteria:

• Patient disagreement;
• Diseases causing cognitive dysfunction;
• Multi organic deficiency;
• Agents affecting central nervous system

Study include patients undergoing cardiac at Clinic of Cardiac, Vascular and Thoracic Surgery, Lithuanian University of Health Sciences