CT observations of a patient presenting an imminent cardiac arrest on the the examination table

Clinical History

A man was admitted at the emergency department for a polytraumatism. He was haemodynamically unstable. Fast measures of intensive care were undertaken, then he was admitted for bodyscanner.
On the examining table he presented a cardiogenic shock; and died within the hour after the examination despite measures of resuscitation.

Imaging Findings

A contrast-fluid level was seen in the thoracic aorta, the vena cava inferior, the right brachiocephalic vein, the right subclavian vein, and some pulmonary vein branches.
At the same examination, we observed an opacification of the vena cava inferior, the vena cava superior, the hepatic veins, both renal veins, and venous branches of the right renal vein, the left lumbar vein, the epidural veins and their plexus, the azygos vein, the pulmonary vein branches, the cervical veins as well as the portal vein and the spleno-mesaraic trunk.
The aorta is of small calibre.

Discussion

CT examination had a primary position in the exploration of polytraumatized patients [1].
In case of trauma, imaging is generally realized after an initial monitoring and a stabilization of the patient by adequate measures of resuscitation [1].
So, to realize an imaging for a person presenting an imminent cardiac arrest is a situation that we can at least refer to as unusual.
The scannographic anomalies of stasis of contrast agent in the dependent parts of the body, observed in post-mortem, were already described in some cases of the English literature.
Our case presents the particularity of being still alive at the time the CT examination was realised; this situation was approached only in some rare English publications. [2, 3]
The retrograde reflux of the contrast agent from the venous system of the upper member towards the vena cava inferior (VCI) and its stasis at the level of the dependent parts with realization of a contrast-blood level indicate the development of a cardiac shock. [3]
The passive hepatic congestion with a diffusely mottled pattern of hepatic enhancement were described in case of right heart failure. [4, 5]
However, an accumulation of the contrast agent in the dependent parts of the venous system implies a bad heart function with incapacity to propel the blood against the gravity. [3]
When the heart stops pumping, the systemic arterial and venous pressures fall significantly, with loss of the arteriovenous pressure gradient. From there, the distribution of the contrast agent depends on the pressure with which it was injected and also of its density. [6]
A product denser than blood tends to accumulate in the dependent regions of the venous system when the heart stops working.
It was also postulated that the positive pressure during the mechanical ventilation can force the precipitation of the contrast agent at the level of the vena cava inferior from the right heart [7].
The opacification of the portal vein and the superior mesenteric vein was already described [7], the most likely mechanism is a retrograde filling after filling of sinusoids and opacification of the dependent parenchyma [8].
The accumulation of the contrast agent at the level of the splenic vein was never described previously, in the absence of contrast at the level of the coeliac artery, the most likely mechanism is a retrograde filling via the portal vein [9].
Yet, The splenic vein is opacified in our patient.

Differential Diagnosis List

Final Diagnosis

Imminent cardiac arrest

URL:	https://www.eurorad.org/case/11493
DOI:	10.1594/EURORAD/CASE.11493
ISSN:	1563-4086