Interrupted inferior vena cava (IVC) is a rare congenital abnormality often combined with cardiovascular and visceral malformations. We report the case of a 63-year-old male who presented in complete heart block with periodic absence of an escape rhythm requiring emergency temporary pacing. The trans-femoral approach was aborted upon discovery of an interrupted IVC; requiring conversion to a trans-jugular approach. In this rare condition the IVC terminates below the hepatic vein and lower limb venous drainage is completed via the azygos and hemiazygos veins into the superior vena cava. The hepatic veins drain directly into the right atrium. It is usually an incidental finding but may be problematic in certain circumstances, such as right heart catheterization procedures, electrophysiological procedures, abdominal, or thoracic surgery. It is usually diagnosed through computed tomography (Figure) or magnetic resonance imaging where the dilated azygos vein can appear as a paravertebral line, widening of the mediastinum, sometimes seen on chest radiography.
In our patient, successful temporary pacing was merely delayed by having to change routes, but failure to recognize the aberrant anatomy (and failure to perform venography at that point) might have lead to injury to the vein. Our case demonstrates that congenital malformations need to be recognized early in the emergency setting to avoid complications.
The full-length version of this report can be viewed at: http://www.escardio.org/communities/EHRA/publications/ep-case-reports/Documents/inferior-vena-cava.pdf
