Transient Global Amnesia Triggered by Migraine in a French Tertiary-Care Center: An 11-Year Retrospective Analysis.

Objective: The etiology of transient global amnesia (TGA) remains unclear, and flow disturbances in the mesial temporal lobes secondary to venous congestion have been proposed as a potential cause. The occurrence of TGA during a migraine attack is a rare condition.

Methods: This 11-year retrospective study in one French center describes patients' characteristics, type of migraine, investigations, treatment with vasoconstrictor during the TGA/migraine attack, and outcome in patients who had TGA during a migraine attack.

Results: Among 8821 new patients, 6 cases of TGA occurring during a migraine attack were identified. For a majority of patients, TGA occurs after the beginning of the attack. TGA always occurs during a severe migraine attack, with vomiting or vomiting efforts. Vomiting or vomiting efforts always precede a TGA episode.

Conclusions: TGA occurring during a migraine attack is rare. Since a Valsalva maneuver, such as forceful vomiting, is frequently described at the origin of the attack, blocking venous return through the superior venous cava may allow brief retrograde transmission of high venous pressure from the arms to the cerebral venous system, resulting in venous ischemia to the diencephalon or mesial temporal lobes and causing TGA.