Mixoma of the heart is an intracavitary primary tumor of the heart, distinguished by benign course and endocardial origin. In connection with the fact that the myxoma of the heart has a characteristic rounded shape and is attached to the inner wall by means of a long "leg", with echocardioscopy, it has the appearance of a mobile neoplasm with distinct smooth contours.
Patients with a myxoma of the left atrium predominate in the general oncological pathology of cardiac patients, which is at least 75%. The defeat of the right atrium and interatrial septum is observed much less often and is most often represented by multiple neoplasms in all cavities of the heart.
Causes of myxoma heart
The main risk category for this oncological pathology is the elderly, but a small percentage of cases is represented by the hereditary form of myxoma, which can occur in any age, and does not depend on gender.
Hereditary form of myxoma of the heart differs polymorphism of clinical and pathomorphological manifestations, therefore, the patient can have widespread myxomatous nodes not only in the heart cavities but also in other structures (subcutaneous fatty tissue, mammary gland, structures of the endocrine system). Family type of myxoma heart is characterized by malignant course and a tendency to repeat recurrence.
Since this new growth occurs very rarely in the general structure of oncopathology, the etiopathogenesis of this pathology has not been sufficiently studied, but it is well known that proliferation and myxomatous degeneration develops from the endothelium. Recently, a scientific study of the consequences of cardiac surgery allows us to conclude that the development of myxoma of the heart is to some extent facilitated by intracavitary surgical intervention on the heart in the anamnesis (percutaneous balloon dilatation of the mitral valve, plastic septal defects).
Symptoms and Signs of Myxoma Heart
Mixoma of the heart is characterized by the polymorphism of clinical manifestations, but each of the individual symptoms observed in the patient can be attributed to one of the three pathognomonic syndromes: general clinical syndrome, symptom complex of intracavitary blood flow disorders and embolic syndrome. It should be taken into account that myxoma of the heart belongs to the category of rapidly progressing oncopathologies, which are characterized by rapid growth and a significant increase in the tumor substrate.
The most common and at the same time nonspecific syndrome is general clinical, the symptoms of which are observed in 90% of patients with myxoma heart. The patient complains of progressive weakness, inability to perform the usual physical activity, decreased appetite, sluggish fever and aching pain in various groups of joints. A more detailed examination of the patient with the above symptoms reveals the following clinico-laboratory signs of the disease: hemolytic type of anemia, inflammatory changes in the blood test, dysproteinemia with an elevated level of immunoglobulins.
The embolic syndrome develops when a part of the tumor substrate is torn off or thrombotic layering in the atrial cavity is formed, followed by their spreading with circulating blood flow to this or that part of the circulatory system. In a situation where the embolus blocks blood flow in the cerebral arteries, the patient develops acute transient ischemic attacks, consisting in a short-term loss of consciousness, the appearance of focal and general cerebral neurologic symptoms. Tumor embolus can obstruct the bloodstream in any blood vessel, even the smallest caliber, for example, the artery of the retina, which leads to irreversible effects in the form of loss of visual function. To develop embolic complications in the pulmonary artery basin, the main source is myxoma of the right atrium.
Symptomocomplex caused by impaired intracavitary blood flow in myxoma of the heart occurs in a situation where the tumor substrate completely obturates the atrioventricular orifice and the mouth of the pulmonary trunk. The consequence of these pathological changes is the emergence of persistent signs of increased intravascular pressure in the pulmonary vascular system, accompanied by severe hemodynamic and respiratory disorders in the form of increasing dyspnea, a dry cough with sputum separation containing an admixture of blood, a pronounced peripheral edematous syndrome, and cardiac rhythm disturbances. The pathognomonic sign of the myxoma of the heart in this situation is a significant improvement in the patient's condition in the horizontal position of the trunk, when the clinical manifestations can disappear and again manifest themselves when the trunk position changes to a vertical position.
Typical manifestations of the myxoma of the right heart are the appearance of generalized edema and accumulation of exudate in the abdominal cavity, small pelvis and between pleural sheets, hepatosplenomegaly and cyanosis of the skin with a predominant lesion of the distal parts of the trunk. Unfortunately, all these signs appear at the late stage of the disease, when the parameters of the tumor substrate reach high values. In view of the similarity of the clinical manifestations of myxoma of the right atrium with signs of mitral stenosis , the patient should be examined for the presence of a valvular heart disease lesion. Mixoma, localized in the cavity of the ventricles of the heart, is rarely manifested by general clinical symptoms and is mostly accompanied by signs of cardiohemodynamic disorders.
An objective examination of the patient using the auscultation technique, unfortunately, does not allow to establish a correct diagnosis, even if there are characteristic features (splitting of the first tone, systolic murmur at the apex of the heart, noise of mitral regurgitation). All of the above signs can be observed in other heart diseases, for example, valvular defects, so they can not be considered specific signs of myxoma heart.
The standard electrocardiographic examination of the patient does not allow to establish reliably the fact of presence of myxomatous changes in this or that part of the heart, and when performing fluoroscopic examination of the chest cavity organs only a slight change in the configuration of the heart is identified as "mitralization". Only in a situation of prolonged course of the disease, accompanied by the formation of many calcifications, it is possible to determine the indirect radiographic signs of the myxoma of the heart.
The most informative and accessible method of visualization of myxoma of the heart is echocardioscopy with transthoracic access, which allows to determine the localization, size, form of tumor growth, its correlation with other heart structures. The distinctive characteristics of the myxoma is its massive vascularization, which is easy to recognize with the use of duplex scanning of the heart.
Treatment of Myxoma Heart
Treatment of any localization of the myxoma of the heart is solely in the operative removal of it, and a radical operation with myxome implies a complete excision of the intracavitary tumor substrate. It is preferable to perform operative removal of the myxomatous node immediately after its detection, since the risk of long-term complications in this pathology is quite large. If delayed in terms of the application of operative treatment of myxoma within two years, the patient can develop a lethal outcome of the disease, which is caused by embolism of large cerebral and coronary arteries.
For myxoma excision, cardiosurgeons prefer to use the medial longitudinal sternotomy access, which allows to sufficiently visualize the affected area. Removal of myxomatous tumor should be maximum, capturing not only the tumor substrate itself, but also nearby tissues. After removal of the neoplasm, a wide wound defect is formed in the region of the interatrial septum, to eliminate which the plastic is used by the excised part of the pericardium. The appearance of signs of recurrence of the disease in a remote postoperative period indicates a violation of the technique for removing the myxoma, as a result of which part of the tumor substrate was not excised. When examining a remote myxoma, it can have both a soft-tissue and a dense structure with a smooth surface of various sizes and shapes.
Removal of myxomatous tumor should be carried out as carefully as possible, since during the operation the risk of embolism from the tumor substrate increases. To this end, the operative manual eliminates the stage of finger revision, and before carrying out the plastic defect resort to a thorough washing of the cavity of the affected atrium in order to visualize the possible remnants of the tumor. In a situation where the myxoma of the heart is accompanied by damage to the valvular apparatus of the heart, cardiac surgeons prefer to simultaneously remove the myxomatous tumor and perform prosthetics of the affected valve.