Background: The multi-tasking approach may be promising for cognitive rehabilitation in cardiac surgery patients due to a significant effect on attentional and executive functions. This study aimed to compare the neuropsychological changes in patients who have undergone two variants of multi-tasking training and a control group in the early postoperative period of coronary artery bypass grafting (CABG). Methods: One hundred and ten CABG patients were divided into three groups: cognitive training (CT) I (a postural balance task with mental arithmetic, verbal fluency, and divergent tasks) (n = 30), CT II (a simple visual–motor reaction with mental arithmetic, verbal fluency, and divergent tasks) (n = 40), and control (n = 40). Results: Two or more cognitive indicators improved in 93.3% of CT I patients, in 72.5% of CT II patients, and in 62.5% of control patients; CT I patients differed from CT II and control (p = 0.04 and p = 0.008, respectively). The improving short-term memory and attention was found more frequently in the CT I group as compared to control (56.7% vs. 15%; p = 0.0005). The cognitive improvement of all domains (psychomotor and executive functions, attention, and short-term memory) was also revealed in CT I patients more frequently than CT II (46.7% vs. 20%; p = 0.02) and control (46.7% vs. 5%; p = 0.0005). Conclusions: The CT I multi-tasking training was more effective at improving the cognitive performance in cardiac surgery patients as compared to CT II training and standard post-surgery management. The findings of this study will be helpful for future studies involving multi-tasking training.

Aim. To evaluate the effectiveness of dual-task computerized cognitive training (CCT) in the prevention of postoperative cognitive dysfunction in patients after on-pump coronary artery bypass grafting (CABG).Material and methods. This cohort prospective study included 68 patients (median age, 64 years [54; 69]) admitted for elective on-pump CABG. In addition to the standard preoperative examination, all patients underwent advanced neuropsychological and neurophysiological examination. Starting from 3-4 days of the postoperative period, all patients underwent dual-task CCT.Results. After 8-10 days, early postoperative cognitive dysfunction was observed in 37 (54,4%) patients from CCT group, while in patients without training in 69,3% of cases (n=79). The best results of cognitive functioning were achieved in neurodynamics and short-term memory. In addition, in patients who completed the training course, a postoperative increase in the frontooccipital gradient of theta rhythm was observed.Conclusion. Neuropsychological and neurophysiological assessment have demonstrated the limited effectiveness of a short-term dual task CCT using in the prevention of early postoperative cognitive dysfunction in patients after on-pump CABG. The dual task method can be an additional preventive intervention in the development of a personalized approach to cognitive rehabilitation therapy in cardiac surgery patients.

Background: There is growing interest in finding methods to enhance cognitive function and comprehend the neurophysiological mechanisms that underlie these improvements. It is assumed that non-pharmacological interventions have better results in cognitive recovery. The aim of this study was to assess the effect of multi-task cognitive training (MTT) on electroencephalographic (EEG) changes and markers of the neurovascular unit in patients undergoing coronary artery bypass grafting (CABG). Methods: This prospective cohort study involved 62 CABG patients aged 45–75 years, 30 of whom underwent a 5–7-day MTT course. The groups of patients were comparable with respect to baseline clinical and anamnestic characteristics. An EEG study was performed before surgery and 11–12 days after CABG. Markers of the neurovascular unit (S100β, NSE, and BDNF) were examined at three time points: before surgery, within the first 24 h after surgery, and 11–12 days after CABG. Results: Patients without training demonstrated higher relative theta power changes compared to the MTT patients. The course of MTT was associated with low plasma S100β concentration but high BDNF levels at the end of the training course. Conclusions: The theta activity changes and the markers of the neurovascular unit (S100β, BDNF) indicated that the severity of brain damage in cardiac surgery patients after a short course of MTT was slightly reduced. Electrical brain activity indicators and vascular markers can be informative for monitoring the process of cognitive rehabilitation in cardiac surgery patients.

Aim of the study was to analyze the event-related synchronization/desynchronization of brain electrical activity during visual selection task in patients underwent on-pump coronary artery bypass grafting (CABG) with and without postoperative cognitive dysfunction (POCD). Material and methods. The study included 32 men who underwent on-pump CABG, mean age 57.2 ± 6.08 years. All patients carried out extended neuropsychological testing, a multi-channel computer electroencephalography (EEG) 3-5 days before CABG and on the 7-10th day after the surgery. The POCD was determined according to the criterion: 20 % decrease in the cognitive indicator compared to that at baseline on 20 % of the tests included in the neuropsychological battery. Monopolar EEGs were recorded in 62 sites of 10-20 system with NEUVO encephalograph (Compumedics, USA) during cognitive task performing in patients wi h and without POCD. Statistical processing was performed using the STATISTICA 10.0. Results. It was found that the POCD patients had less pronounced theta desynchronization in the left frontal-central regions during the stage of 200-400 ms at the 7-10 days after CABG in comparison to patients without cognitive decline. Moreover, in the left parietal leads POCD patients had decreased theta desynchronization during the stage of 200-400 ms even before the surgery. At the 7-10 days after CABG, only the patients without POCD had a decrease of event-related theta activity in the left parietal leads compared with baseline. During the stage of 600-800 ms, the POCD patients had a lower degree of theta-desynchronization of both frontal-central and parietal regions of right hemisphere compared to patients without cognitive decline. Conclusion. The cognitive decline in patients after CABG determined according to neuropsychological testing is accompanied by pathological changes in the event-related theta activity. An analysis of event-related synchronization/desynchronization can be used both as predictor of postoperative cognitive impairment and as objective marker of POCD.

Aim. To assess the effects of cognitive rehabilitation with dual-task training that involves a cognitive task combined with postural and walking control, as well as electroencephalogram indices in patients in the early postoperative period after direct myocardial revascularization.Methods. The study enrolled 48 patients scheduled for coronary artery bypass graft surgery. Subjects in this prospective, randomized study were randomized using envelopes to a postoperative cognitive training group (n = 23) and non-training group (n = 25). The cognitive training was carried out daily, starting 3-4 days after the procedure and until the discharge order. Dual tasks training (a cognitive task combined with postural and walking control) lasted 15-20 minutes. All patients were submitted to an extended neurophysiological assessment (psychometric tests and electroencephalogram study) and stabilography 3-5 days before and 8-11 days after coronary artery bypass grafting.Results. The patients who underwent cognitive training experienced postoperative cognitive dysfunction (POCD) in 39% cases in the early postoperative period after intervention, while the non-training group - in 64%. The relative risk of developing POCD in the non-training group was 2.77 (95% CI: 0.86-8.91, Z = 1.704, p = 0.08). The patients in cognitive training exhibited better cognitive state compared to the preoperative state (Z = 2.58; p = 0.01) in the absence of statistically significant differences in the non-training group. Moreover, type-1 theta power values increased in the non-training group in comparison to the preoperative values, while the cognitive training group did not have a statistically significant difference in theta power.Conclusion. Positive effects of dual task rehabilitation on the neurophysiological parameters of patients undergoing direct myocardial revascularization were demonstrated. Positive effects include lower frequency of POCD, improved cognitive state and less pronounced cortical dysfunction. The dual task training had proved a suitable training method for this category of patients. Additional studies are required to test the possibility of increasing the duration and intensity of dual task training for stronger recovery effect and improved cognitive and walking performance of patients in the postoperative period after direct myocardial revascularization.

The paper analyzes modern literature on methods of cognitive functions recovery as dual tasks, implying simultaneous execution of motor and cognitive tasks. There is ambiguity of currently obtained data on the effectiveness of dual tasks in cognitive rehabilitation of elderly people, people with traumatic and neurodegenerative brain damage. It is assumed that the success of dual tasks is associated with the severity of transfer and interference effects. Opportunities and prospects of using dual tasks in cognitive rehabilitation of patients after cardiac surgery are outlined.