Selective 4 vessels angiography in brain death: a retrospective study

In Canada, ancillary tests, such as selective four vessels angiography (S4VA), are sometimes necessary for brain death (BD) diagnosis when the clinical exam cannot be completed or confounding factors are present. Recent Canadian guidelines assert that brain death is supported by the absence of arterial blood flow at the surface of the brain and that venous return should not be considered. However, neuropathologic and angiographic studies have suggested that arteries might still be patent in BD patients. Current clinical practices in BD diagnosis following S4VA need to be better understood.

We conducted a retrospective study of all S4VA performed for the determination of BD in a level 1 NeuroTrauma centre from 2003 to 2007. The objective of the study was to describe the prevalence of intracranial arterial, capillary (parenchymogram) and venous opacification in our study population. All tests were reviewed independently by two neuroradiologists. Disagreements were resolved by consensus.

Thirty two patients were declared BD following S4VA during the study period. Nine of these patients (28%) presented some proximal opacification of intracranial arteries (95% CI 15-45%). As opposed, none had a cerebral capillary and deep venous drainage opacification (95% CI 0-10%).

The absence of cerebral deep venous drainage or parenchymogram might represent a better objective marker of cerebral circulatory arrest for brain death diagnosis when the use of S4VA is required. These findings open the path for further research in enhancing our interpretation of angiographic studies for brain death diagnosis.