Effect of Carotid Stenosis Severity on Patterns of Brain Activity in Patients after Cardiac Surgery

Abstract

Background: The negative effects of high-grade carotid stenosis on the brain are widely known. However, there are still insufficient data on the brain state in patients with small carotid stenosis and after isolated or combined coronary and carotid surgery. This EEG-based study aimed to analyze the effect of carotid stenosis severity on associated brain activity changes and the neurophysiological test results in patients undergoing coronary artery bypass grafting (CABG) with or without carotid endarterectomy (CEA). Methods: One hundred and forty cardiac surgery patients underwent a clinical and neuropsychological examination and a multichannel EEG before surgery and 7–10 days after surgery. Results: The patients with CA stenoses of less than 50% demonstrated higher values of theta2- and alpha-rhythm power compared to the patients without CA stenoses both before and after CABG. In addition, the patients who underwent right-sided CABG+CEA had generalized EEG “slowdown” compared with isolated CABG and left-sided CABG+CEA patients. Conclusions: The on-pump cardiac surgery accompanied by specific re-arrangements of frequency–spatial patterns of electrical brain activity are dependent on the degree of carotid stenoses. The information obtained can be used to optimize the process of preoperative and postoperative management, as well as the search for neuroprotection and safe surgical strategies for this category of patients.

Postoperative Cognitive Dysfunction and Virtual Reality for Cognitive Rehabilitation in Cardiac Surgery Patients: A Short Review

“…Our preliminary research has revealed the positive effects of multitasking training on cognitive functions in cardiac surgery patients. Compared to a more manageable task, the training with a complex motor task resulted in better figurative memory, psychomotor speed, and attention indicators [20]. This study used a short course (5-7 training sessions) for multitasking training.…”

“…It is diagnosed based on neuropsychological testing data in the postoperative period [21]. Various neuropsychological tests are utilized to diagnose postoperative cognitive decline in current studies, thereby making direct comparisons of their results challenging [7,8,20]. The best possible results are obtained by an extended neuropsychological examination using specialized neuropsychological tests assessing memory, attention, psychomotor, and executive functions [8,20].…”

“…Various neuropsychological tests are utilized to diagnose postoperative cognitive decline in current studies, thereby making direct comparisons of their results challenging [7,8,20]. The best possible results are obtained by an extended neuropsychological examination using specialized neuropsychological tests assessing memory, attention, psychomotor, and executive functions [8,20]. To enable cross-study comparisons, postoperative cognitive decline should be defined by established criteria, such as a 20% reduction in cognitive scores compared to baseline on 20% of neuropsychological tests or a decline of 1-2 standard deviations in a specific domain, with the standard deviation calculated as the cross-sectional standard deviation of the baseline scores [8,20,22].…”

“…Applying the multitasking approach with the simultaneous execution of motor and cognitive tasks requires considerable control by the attention and executive functions [45]. Preliminary data has shown that multitasking training can provide effective cognitive and motor recovery in patients with ischemic brain damage and optimize cognitive and physical functions [19,20]. The positive impact of training on cognitive functions shortly after CABG is significant in promoting medical adherence and optimizing rehabilitation procedures overall.…”

“…Multimodal training in virtual reality (VR) could be a possible approach [18]. Preliminary data show that training interventions using a multimodal approach can provide effective cognitive recovery in cardiac surgery patients, optimize cognitive and physical functions, and improve quality of life [19,20].…”