Peculiarities of Histological Structure of Pulmonary Veins in Patients with Total Anomalous Pulmonary Venous Drainage as Morphological Substrates Relating to Formation of Postoperative Pulmonary Venous Obstruction.

The histological and immunohistochemical methods were employed to examine the peculiarities of histological structure of pulmonary veins and left atrium of the heart in norm and in various types of total anomalous drainage of pulmonary veins. In contrast to normal pulmonary vein covered with external multiple muscle layers (myocardial sleeve), such sleeve is absent in veins that have no connection with the left atrium irrespective of the type of the defect. In patients with total anomalous pulmonary venous drainage, the structure of left atrium was heterogeneous featuring either the presence or absence of inner angiomural lining in this atrium. The structural peculiarities are important for insight into etiology of the development of postoperative pulmonary venous obstruction in patients with total anomalous pulmonary venous drainage.