ENDOVASCULAR FEATURES OF CARDIAC MYXOMA BLOOD SUPPLY
Introduction: the main methods for diagnosing cardiac neoplasms, allowing to determine the localization, size, involvement of heart structures, to suggest the nature of the pathological process and to plan treatment tactics, are: echocardiography (EchoCG), contrast multispiral computed coronary angiography (MSCT CAG), magnetic resonance imaging (MRI) and positron emission computed tomography (PET CT). At the same time, any additional information about the pathological process can improve the quality of diagnosis and treatment. So, for example, selective coronary angiography (CAG), which in this case can be performed to clarify the coronary anatomy and exclude concomitant coronary atherosclerosis, in hands of attentive and experienced specialist of endovascular diagnostic and treatment methods can make a significant contribution to understanding the nature of blood supply of heart neoplasm, thereby bringing closer the formulation of the correct diagnosis and, ultimately, improving results of surgical treatment. Aim: was to study the nature of blood supply of heart myxoma based on results of a detailed analysis of data of selective coronary angiography in patients with this pathology. Material and methods: since 2005, 20 patients underwent surgery to remove heart myxoma. The average age of patients was 56,6 + 8,0 (43-74) years. According to data of ultrasound examination, sizes of myxomas ranged from 10 to 46 mm in width and from 15 to 71 mm in length (average size ˗ 25,6 × 39,1 mm). In 2/3 of all cases (15 out of 20,75%), the fibrous part of the inter-atrial septum (fossa oval region) was the base of myxomas. In 8 of 20 (40%) cases, tumor prolapse into the left ventricle through structures of the mitral valve was noted in varying degrees. In order to exclude coronary pathology, CAG was performed in 14 cases, in the rest - MSCT CAG. Results: of 14 patients with myxoma who underwent selective coronary angiography, 12 (85,7%) patients had distinct angiographic signs of vascularization. In all 12 cases, the sinus branch participated in the blood supply of myxoma, begins from the right coronary artery (RCA) in 10 cases: in 7 case it begins from proximal segment of the RCA and, in 3 cases, from the posterior-lateral branch (PLB) of the RCA. In one case, the source of blood supply of neoplasm was the sinus branch extending from PLB of dominant (left type) circumflex artery of the left coronary artery (PLB CxA LCA). In one case, the blood supply to the neoplasm involved branches both from the RCA and CxA, mainly from the left atrial branch of CxA. Moreover, in all 12 cases, sinus branch formed two branches: branch of sinus node itself and left atrial branch. It was the left atrial branch that was the source of blood supply of myxoma. Analysis of angiograms in patients with myxoma of LA showed that left atrial branch in terminal section formed a pathological vascularization in the LA projection, accumulating contrast-agent in the capillary phase (MBG 3-4). In addition to newly formed vascularization, lacunae of irregular shape were distinguished, the size of which varied from 2 to 8 mm along the long axis. In 8 cases, hypervascular areas with areas of lacunar accumulation of contrast-agent showed signs of paradoxical mobility and accelerated onset of venous phase. In two cases, there were distinct angiographic signs of arteriovenous shunt. In 2 cases (when the size of the myxoma did not exceed 15-20 mm according to EchoCG and CT), angiographic signs allowing to determine the presence of LA myxoma were not so convincing: there was no lacunar accumulation of contrast-agent; small (up to 10 mm) hypervascular areas were noticed, the capillary network of which stood out against the general background of uniform contrasting impregnation and corresponded to MBG grade 1-2. Conclusion: according to our data, angiographic signs of vascularization of myxomas are detected in most cases with this pathology (85,7%). The source of blood supply, in the overwhelming majority of cases, is branch of coronary artery, which normally supplies the structure of the heart, on which the basement of the pathological neoplasm is located. The aforementioned angiographic signs characteristic of myxomas deserve the attention of specialists in the field of endovascular diagnosis and treatment and should be described in details in protocols of invasive coronary angiography.