Contrast-fluid level in the inferior vena cava (IVC niveau sign) in patients with acute type A aortic dissection: computed tomography findings during acute cardiac tamponade

Abstract

The presence of the IVC niveau sign suggests acute cardiac tamponade in patients with acute type A aortic dissection.

Dependent layering of venous refluxed contrast: A sign of critically low cardiac output

“…The most important of these is a pooling and dependent layering of contrast within the IVC and its tributaries creating a blood-contrast level. This finding is referred to as the IVC level sign [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] .…”

“…Whereas the specific gravity of whole blood at body temperature is approximately 1.062 [22] , that of commonly utilized iodinated contrast medium preparations ranges between 1.280 and 1.406 [23] . Hence, in a hypostatic state , iodinated contrast material will layer dependently in relation to whole blood [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] . In a patient in cardiogenic shock, a contrast bolus passively refluxes into the IVC and systemic venous circulation.…”

“…Consequently, with first pass circulation and recirculation significantly hindered or absent, the bolus is never redistributed within the intravascular and extracellular spaces. Remaining concentrated, hypostatic contrast material layers dependently in relation to unopacified whole blood in the intravascular space, creating a characteristic blood-contrast level in the IVC [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] . When visualized on contrast-enhanced CT, this finding is called the “IVC level,” niveau or “dependent pooling sign” [8] , [11] , [12] , [14] .…”

“…Remaining concentrated, hypostatic contrast material layers dependently in relation to unopacified whole blood in the intravascular space, creating a characteristic blood-contrast level in the IVC [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] . When visualized on contrast-enhanced CT, this finding is called the “IVC level,” niveau or “dependent pooling sign” [8] , [11] , [12] , [14] . The sign has been observed in shock due to cardiac arrest [8] , [9] , cardiac tamponade [8] , [12] , [14] and myocardial infarction [11] .…”

“…When visualized on contrast-enhanced CT, this finding is called the “IVC level,” niveau or “dependent pooling sign” [8] , [11] , [12] , [14] . The sign has been observed in shock due to cardiac arrest [8] , [9] , cardiac tamponade [8] , [12] , [14] and myocardial infarction [11] . Here, we present cases of cardiac tamponade and arrest.…”