What causes this patient to faint after drinking?

An unusual case of syncope points to a sinister cause

Rachel is a 49-year-old mother of four who was previously well. She presents to her GP after an episode of syncope that occurred at her son's birthday, after consuming two glasses of wine.


Rachel felt fleetingly unwell, then experienced a brief episode of blurred vision before collapsing. A family member helped her to the ground and there was no seizure activity or injury.

Her sister-in-law noticed Rachel's lips were blue. She was unconscious for up to 15 minutes, while family members administered CPR, but she recovered before paramedics arrived and did not go to hospital.