Cerebral arteriovenous malformations: features of the functioning of the blood circulation system after endovascular treatment with long-term monitoring

Abstract
Objective ‒ to determine the features of the functioning of the circulatory system in patients with arteriovenous malformations (AVM) of the brain after endovascular operations with long-term observation.Materials and methods. 479 patients with cerebral AVM were examined and treated, of which 377 (78.7 %) were men and 102 (21.3 %) were women. The average age of patients was (27.5±3.5) years. Patients aged 18‒30 years predominated (75.4 %). A dynamic observation of 347 patients after endovascular treatment after 3, 6, 12 and 24 months and more was carried out. Patients underwent cerebral angiography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, echocardiography, Doppler cardiography, electrocardiography, duplex scanning of cerebral vessels.Results. The study shows the effect of arteriovenous shunting on cerebral and systemic hemodynamics in general. Switching off AVM from the cerebral blood flow improved cerebral hemodynamics already in the early postoperative period, the changes were more significant after 3‒6 months of observation and in some cases reached values ​​in healthy individuals 2 years after the operation. In 52.8 % of patients with AVM, systemic circulation disorders occurred due to an increase in heart rate, minute and stroke blood volumes, left ventricular ejection fraction with an increase in mechanical load on the heart, which led to changes in systolic contraction and diastolic relaxation of the left ventricle of the heart with the development of heart failure. Switching off the AVM from the cerebral blood flow did not cause significant changes in heart functions in the early postoperative period; positive changes occurred over a long period. Dynamic observation showed a positive restructuring of the functioning of the circulatory system in patients after endovascular exclusion of the malformation.Conclusions. Arteriovenous malformations are hemodynamically active systems that lead to hemodynamic-perfusion changes, both at the local and at the general hemodynamic level. The exclusion of the malformation from the bloodstream contributes to the regression of disorders of cerebral and intracardiac blood flow caused by the anatomical and functional characteristics of the malformation itself and its clinical course.