Subarachnoid hemorrhage after transient global amnesia caused by cerebral venous congestion: case report

BACKGROUND: Transient global amnesia is reported to be caused by cerebral venous congestion. Internal jugular venous flow reversal in particular with the Valsalva maneuver leads to cerebral venous congestion. In addition, Valsalva maneuver can also induce subarachnoid hemorrhage. Transient global amnesia and subarachnoid hemorrhage might have common a pathophysiology in cerebral venous congestion. CASE PRESENTATION: We report here the case of a 57-year-old woman who twice experienced convexal subarachnoid hemorrhage just after straining at stool following an episode of transient global amnesia. Digital subtraction angiography showed left temporal congestion. Left jugular vein ultrasonography revealed reflux with the Valsalva maneuver only in acute phase, indicating transient cerebral venous congestion. CONCLUSIONS: Subarachnoid hemorrhage followed by transient global amnesia indicates a common factor between them. Transient venous congestion is discussed in order to explain this rare phenomenon. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12883-018-1042-3) contains supplementary material, which is available to authorized users.