Fetal left brachiocephalic vein in normal and abnormal conditions

Abstract

Objectives To establish values of fetal left brachiocephalic vein (LBCV) dimensions during normal pregnancy and determine whether routine assessment of the LBCV may help in identifying fetuses with congenital abnormalities of this vessel. Methods

Ultrasonographic features of the persistence of superior left vena cava and pathological cardiac associations in fetus. Case series.

“…rSVC -right superior vena cava, DA -ductus arteriosus, Desc Ao -descending aorta, asterix -persistent left superior vena cava with abnormal arrangement in the absence of the superior right vena cava [6][7][8]. For the diagnosis of the PLSVC is useful to demonstrate the absence of the brachiocephalic vein [1] and a "putter" appearance of the supernumerary vessel with trajectory behind the heart in connection with the coronary sinus. The Color Doppler examinaton is useful for the follow-up of the vessels confluence.…”

“…Persistent left superior vena cava (PLSVC) is the proximal segment of anterior left cardinal vein, which results from the lack of atrophy that normally follows the formation of left brachiocephalic vein [1]. PLS-VC is the most frequent encountered anomaly of the thoracic systemic venous return (0.3%-0.5% in the general population) [2,3].…”

The gap between the aorta and the superior vena cava: A sonographic sign of persistent left superior vena cava and associated abnormalities

“…While the presence and the course of the left brachiocephalic vein could not be retrospectively assessed in all cases and controls, we hypothesize that the findings can be explained by the fact that in the case of a bilateral SVC, the left brachiocephalic vein is missing in up to 65% of the cases and that the two vessels share the venous drainage of the upper part of the body to the right atrium . Moreover, if the venous drainage from the left to right brachiocephalic vein is missing, the traction on the right SVC toward the left side might be less pronounced.…”

“…A failure of involution of the left anterior cardinal vein results in a persistent left SVC, in which case the venous drainage of the upper body occurs through both left and right SVC . The left brachiocephalic vein that usually crosses horizontally in the upper mediastinum anteriorly to the three branches of the aortic arch and finally empties into the right brachiocephalic vein is often missing . Therefore, it is plausible that the traction of the left brachiocephalic vein on the right SVC toward the midline of the mediastinum is absent.…”

Correlation Between the Thymic‐Thoracic Ratio and Cardiac Axis in Healthy Fetuses

“…The anteroposterior diameter, transverse diameter, and perimeter are among the most commonly used measurements . The fetal thymus can be identified by using several landmarks, including the 3‐vessel edge in the 3‐vessel view, internal mammary arteries, and brachiocephalic veins . Three‐dimensional US and 4‐dimensional spatiotemporal image correlation have been used to calculate the volume of the fetal thymus .…”