The particularity of this anatomy resulted, in our case, in the left brachiocephalic vein stenosis by a temporal right subclavian hemodialysis catheter.
Caption: FIGURE 2: Vascular access angiography: stenosis of the left brachiocephalic vein close to the superior vena cava.
The hemiazygos system (HV and AHV), together with the left superior intercostal vein, drains the lower eight left posterior intercostal and upper four left posterior intercostal veins (LPIVs) into the azygos and left brachiocephalic veins
, respectively (Dahran & Soames, 2015).
The left brachiocephalic vein receives lymph from the thoracic duct [Figure 2].
Sometimes, the accessory hemiazygos vein may drain either directly or after forming a common trunk with the left superior intercostals vein into the left brachiocephalic vein. [sup] The frequency of accidental azygos vein cannulation during a central venous access through IJV is 0.7-1.2%.
The thoracic duct drains into the distal portion of the left brachiocephalic vein. If the needle punctures the thoracic duct directly at the orifice of the duct into the left brachiocephalic vein, the guidewire is advanced through the needle directly into the thoracic duct and then followed the course of the duct downward on a level with the cisterna chili.
Our case presents a left-sided upper PAPVR through a "curved" vein that drains to left brachiocephalic vein. Another finding is an independent lingular vein that joins the left atrium.
To our knowledge, this is the first case that described a left-sided upper PAPVR through a "curved" vein, which goes first inferiorly and then medially to the left pulmonary artery to join the left brachiocephalic vein, because the cases of left-sided upper PAPVR reported in the literature typically present a "vertical" vein located laterally to the left pulmonary artery.
Contrast enhancement chest CT, performed in the portal venous phase as our usual staging protocol, reveals that the left upper pulmonary vein presents an anomalous route: it first runs under the left pulmonary artery, then goes up medially to it, runs via the aortopulmonary window, and finally joins the left brachiocephalic vein, describing on the whole a curved line with superior concavity (Figures 1 and 3).
LBV= Left brachiocephalic vein
; SVC= Superior vena cava; Ao= Aorta; Az= Azygos vein; AHA= Accessory hemiazygos vein; HAz= Hemiazygos vein and IAz= Interazygos vein.
Right and left superior intercostal veins have been traced to their points of termination into the right and left brachiocephalic veins
, correspondingly the hemiazygos and the accessory hemiazygos are traced on the left side of the bodies of the thoracic vertebrae behind the descending thoracic aorta.
The most important vessels found in this region are the internal and external jugular veins, axillary vein, costocervical, deep cervical, vertebral, left brachiocephalic veins
and the cranial vena cava, in addition to the left common carotid, axillary, costocervical trunk, dorsal scapular, deep cervical and superficial cervical arteries (POPESKO, 1997).