[Characteristics of postoperative cerebral dysfunction depending on the type and position of the implanted prosthetic heart valve]. / Osobennosti posleoperatsionnoi mozgovoi disfunktsii v zavisimosti ot tipa i pozitsii implantiruemogo proteza klapana serdtsa.

AIM: To study the prevalence and structure of postoperative cerebral dysfunction depending on the type and position of the implanted prosthetic heart valve in patients who underwent surgery for the acquired heart valve disease. MATERIAL AND METHODS: The study included 115 patients (70 men and 45 women; 64 [56; 72] years old), who underwent elective replacement or repair surgery for the acquired heart valve disease. RESULTS AND CONCLUSION: The postoperative cerebral dysfunction was diagnosed in 40.9% patients, including replacement in the aortic position (45.5%), in the mitral position (55%), in several positions (20%). Replacement surgery was accompanied by three clinical types of postoperative cerebral dysfunction and repair surgery - by deferred cognitive impairment only. Postoperative cerebral dysfunction after the replacement in the mitral position was more common (odds ratio 4.47, 95% confidence interval 1.21-18.35, p=0.041), including its acute clinical types - perioperative stroke and symptomatic delirium of the early postoperative period (p=0.029), compared to that after the repair heart valve surgery. After the replacement in the aortic position, acute clinical types of postoperative cerebral dysfunction were more common (p=0.036). After the replacement with biological prosthesis, symptomatic delirium of the early postoperative period was more common (p=0.047). The occurrence of the deferred cognitive impairment didn't depend on the type and position of the implanted prosthetic heart valve.

[Perioperative stroke in heart valve surgery: pathogenesis, clinical findings, diagnosis, prevention, treatment]. / Perioperatsionnyi mozgovoi insul't v khirurgii klapanov serdtsa: patogenez, klinika, diagnostika, lechenie i profilaktika.

AIM: To study risk factors, characteristics of clinical symptoms and diagnosis, and possibilities of prevention of perioperative stroke and other clinical types of cerebral dysfunction in main types of heart valve surgery. MATERIAL AND METHODS: The study included 83 patients, aged 63 (54; 70) years, undergoing heart valve surgery with cardiopulmonary bypass. RESULTS: Postoperative cerebral dysfunction was diagnosed in 37.3% of cases, including perioperative stroke in 3.6% of cases. In cases of aortic stenosis, the frequency of perioperative stroke was 9.5%. The cardioembolic subtype of perioperative ischemic stroke in cardiac valve surgery was most likely. The risk factors of the symptomatic delirium of the early postoperative period are: age over 75 years, preoperative frontal dysfunction, duration of artificial respiratory care more than 20 hours after the surgery. CONCLUSION: The results suggest the efficacy of preventive use of cytoflavin for reducing the frequency and severity of perioperative stroke and symptomatic delirium of the early postoperative period in heart valve surgery with cardiopulmonary bypass.

[Modern strategies of protection of hypoxic-ischemic brain damage]. / Sovremennye strategii zashchity pri gipoksicheski-ishemicheskom povrezhdenii golovnogo mozga.

Nowadays, there are two complementary approaches to treatment of patients with ischemic stroke: reperfusion and neuroprotection. The main purpose of neuroprotection is to intervene ischemic cascade at every stage of the pathological process and thus avoid the death of nerve cells and expand the therapeutic window for reperfusion therapy. The use of drugs with neurotrophic, antioxidant and neuroregenerative effects is pathogenically explained at all stages of post stroke rehabilitation. Ethylmethylhydroxypyridine succinate (mexidol) is a derivative of succinic acid with antihypoxic, membrane protective, nootropic, anticonvulsant and sedative action. The majority of researchers confirmed the positive effect of mexidol expressed as the marked regression of neurological deficit and wider opportunities for further early rehabilitation. The results of the randomized double blind multicenter placebo-controlled, parallel-group trial of the efficacy and safety of prolonged sequential therapy with mexidol in the acute and early recovery stages of hemispheric ischemic stroke (EPICA) were published in 2017. The results of the study showed the best positive dynamics of neurological function recovery in case of timely treatment with mexidol with the following two month therapy. The safety of the long-term use of mexidol was confirmed.

[Characteristics of the regulation of neurotrophic mechanisms in ischemic stroke].

AIM: To explore the endogenous and pharmacological activation of neurotrophic mechanisms in a model of brain ischemic lesion in rats. MATERIAL AND METHODS: The study was performed on 170 male albino rats (195-205 g). The model of ischemic stroke was accomplished by the electrocoagulation of the proximal segment of the left middle cerebral artery and simultaneous permanent ligation of the left common carotid artery. RESULTS AND CONCLUSION: The evaluation of NSE, NO, VEGF, NGF levels in the brain cytoplasmic lysate and plasma showed the delayed activation of neurotrophic mechanisms in astrocytes accompanied by a decrease in delayed alteration of neurons. The use of cytoflavin in the treatment of stroke was accompanied by the earlier and more intense activation of neurotrophic mechanisms in astrocytes, delayed activation of neurotrophic mechanisms in endothelial cells, which promoted neuroprotection in acute ischemic stroke.

Central and cerebral hemodynamics and metabolism of the healthy man during head-down tilting.

Experiments on six healthy test volunteers, who underwent simultaneous catheterization of different cardiovascular compartments, were carried out to study the effect of head-down tilting at an angle of -20 degrees on the central and cerebral hemodynamics and metabolism. By the third hour of exposure, the test subjects showed a decrease in the systolic arterial pressure and increases in the systolic pressure of the right ventricle, heart rate, cardiac output, and oxygen intake. They also displayed a trend for an increase in the content of adenosine triphosphate, a decrease in the content of pyruvic acid, and essentially no changes in the concentration of lactic acid and activity of lactate dehydrogenase in the arterial blood and in the blood flowing out from the brain. The oxygen arteriovenous difference for the systemic and cerebral circulation decreased by 24% and 13%, respectively. The above circulatory and metabolic changes seem to reflect processes of adaptation of the human body to functioning under conditions of cephalad fluid shifts.