5th May 2025

A 70-year-old gentleman presents on the acute medical ward with a fall and sudden loss of consciousness.

A 70-year-old gentleman presents on the acute medical ward with a fall and sudden loss of consciousness. The history from the ambulance crew was of sudden loss of consciousness with some jerking movements. His oxygen saturations were normal on ambulance assessment with a heart rate of 110 beats per minute. A venous blood gas in the emergency department revealed a normal serum lactate. A 12-lead ECG shows atrial fibrillation with a ventricular rate of 55 beats per minute. His oxygen saturations are 91% on room air; he is an ex-smoker with known chronic type 2 respiratory failure. You note a past medical history of hypertension, type 2 diabetes and ischaemic heart disease with PCI to the left anterior descending and circumflex coronary arteries. You hear no murmurs on cardiac examination. Which factor in the history makes a cardiac cause the most likely culprit of his underlying arrhythmia?

Select the SINGLE most appropriate option from the list below. Select ONE option only.