Arteriovenous forms of congenital vascular malformations of extremities: aspects of pathogenesis

Abstract

The aim — to improve the results of treatment of patients with arterio‑venous forms (AVF) of congenital vascular malformation (CVM) of extremities based on the study of etiopathogenetic aspects of pathology. Materials and methods. Work is based on data of complex clinical research and surgical treatment of 155 patients with the arteriovenous forms of congenital vascular malformation of extremities. There were 65 (42 %) men, 90 (58 %) women, average age — 25.1 ± 10.4 years. The children’s age group (up to 18 years old) is formed of 53 (34 %) persons. The analysis of clinical material is viewed depending on the clinical‑anatomical forms of CVM, which were subdivided into 11 groups on the basis of «working» classification scheme «VASC +T»: I—VII — macrofistulous forms (trunkular, extratrunkular, combined), VIII — IX — micrоfistulous forms, X—XI — mixed or combined forms (with predominance of venous component and presence of single microfistulas). Distribution by prevalence: diffuse forms — groups I — IV, VIII, X; localized forms — groups V—VII, IX, XI. Assessment of chronic arterial and venous insufficiency for each patient was carried out. Results and discussion. Diffuse macrofistulous AVF of CVM are hemodynamically more severe, causing the hypertrophy of soft tissues and more expressed clinical displays of chronic arterial (26 (17 %)) and cardiac (25 (16 %)) insufficiency. Diffuse microfistulous CVM (group VIII) and mixed forms with existence of microfistulas (group X) are characterized by more severe manifestations of chronic venous hypertension (88 (56.8 %)) and vascular‑bone syndrome (56 (36 %)). The most severe manifestations of systemic hemodynamic disorders were revealed in diffuse macrofistulous forms, although, according to most parameters, disturbances in diffuse macro‑ and microfistulous AVF of CVM are comparable and of the same type. Pathomorphological (66 (45.8 %)) and immunohistochemical studies (10.7 %) revealed the presence of proliferative activity of angiomatous tissues and degenerative changes in the walls of the angiodysplastic vessels both due to developmental defects and pathological disorders of hemodynamics. The source of progression of AVF of CVM is vessels of the microvasculature (capillaries) and microfustulas, proceeding from the level of VEGF and Ki‑67. Conclusions. The study of hemodynamic and pathomorphological aspects of the pathogenesis of AVF of СVM is necessary for planning of an individual differentiated approach in diagnosis and treatment, depending on the clinical and anatomical form of the disease.