A controlled Valsalva Maneuver causes neither Diffusion-Positive Hippocampal Lesions nor Clinical Symptoms after Transient Global Amnesia.

Valsalva maneuver (VM) precedes frequently transient global amnesia (TGA) and up to 84% of the patients with TGA present hippocampal diffusion-weighted imaging-positive (DWI+) lesions on brain magnetic resonance imaging (MRI). We studied 20 patients with TGA and hippocampal DWI+ lesions. Median age (range) of the patients was 67 (57-80) years and 55% were women. TGA had been preceded by a VM-associated activity in 14 patients (70%), and brain MRI had been performed at a median (range) of 47.5 (42-79) h after TGA. These patients underwent a second MRI after a controlled-induced VM at least 3 months after TGA. This MRI was performed at a median (range) of 46.8 (41-138) h after the controlled-induced VM. None of the patients who reproduced TGA symptoms presented new DWI+ lesions on the second MRI. In patients with a previous episode of TGA, VM cannot elicit TGA in isolation and the interplay of other simultaneous factors is needed.