Mediastinal malposition of a catheter enhanced by an unusual stenosis of the left brachiocephalic vein due to a former long-term haemodialysis catheter

The catheterization of a central vein is a routine invasive procedure in medicine. Nevertheless, it has potential severe (sometimes fatal)
complications which are prevented by anticipation of risk factors and a careful and a posteriori-controlled placement with the use of chest
radiograph or when necessary computed tomography (CT) scan. We are reporting the case of a mediastinal malposition of a hemodialysis
catheter with perforation of the left proximal brachiocephalic vein caused by a downstream venous obstruction. That obstruction was revealed
on the chest CT scan by an opacity along the left innominate vein suggesting the calcification of either a catheter cast or a thrombus due to a
former long-term subclavian hemodialysis catheter removed a few days earlier. These conditions may be falsely diagnosed as catheter fragment
retention which would lead to an unnecessary and dangerous invasive procedure of extraction. Our goal is to highlight those rare complications
as well as to discuss their prevention.