Totally anomalous pulmonary venous drainage – supracardiac type: ultrasound assessment of anatomically determined stenosis of the vertical vein collecting pulmonary venous return

The diagnosis of the congenital heart defects, among others totally anomalous pulmonary venous drainage, is based on echocardiography. While the visualization of intracardiac structures rarely causes significant difficulties, the vessels positioned outside the heart, e.g. the pulmonary veins, are often hidden behind tissues impermeable to ultrasounds, which may necessitate the use of other imaging methods, such as computer tomography, nuclear magnetic resonance or angiocardiography. The serious limitation of these techniques, especially in pediatric age, is the necessity to administer general anesthesia and contrast media. In order to obtain clear images, the appropriate concentration of a contrast agent in the vessels is necessary, which is not always possible in a patient with severe circulatory failure. Therefore, every effort should be made to obtain as much information necessary for treatment determination as possible from echocardiography, in spite of its limitations. A significant morphological factor of totally anomalous pulmonary venous drainage is the connection between the pulmonary and systemic veins, which in the supracardiac type is the vertical vein draining into the left brachiocephalic vein. The narrowing of this connection impedes the return of the blood from the lungs, which leads to the secondary edema and severe, abrupt cardiorespiratory insufficiency. Such a narrowing should be sought for in every case of totally anomalous pulmonary venous drainage since it constitutes an indication for an urgent surgery. On the basis of own experience and information obtained from the pertinent literature, the authors describe the rules and criteria of the diagnosis of this rare supracardiac form of the heart defect with the presence of the vertical vein which may undergo stenosis due to a phenomenon called the anatomical or bronchoarterial vise. It is formed when the vessel “pushes through” a narrow opening bordered by the left pulmonary artery from the inferior side as well as the left main bronchus and the arterial duct or ligament from the superior side. This article describes a technique of echocardiographic test enabling the precise visualization of the vessel's course and the differentiation from a more common variant of the defect – without external stenosis.