Getting to the root of a rapid cognitive decline

A patient presents after fainting. What's causing his illness?

Zhen is a 75-year-old Chinese gentleman who is generally very well.


He is squeezed in urgently after a syncopal episode an hour previously, on the background of two days of general malaise, lethargy and fever.

He has ongoing pre-syncopal symptoms.


On assessment his BP is 117/63, HR 63 and irregular, temperature 37.9°C. He has a haematoma overlying the bridge of his nose.

He has no other cardiovascular or neurological findings of note. ECG shows new slow atrial fibrillation.