Good morning everyone. Continue the week with a real case. You are the doctor on call. It is 3am. A 58 year old man on the ward is reviewed by nursing staff for palpitations and mild breathlessness. He has a background of hypertension. His observations, heart rate 142, blood pressure 108 over 70, oxygen saturation 96 percent on air. His ECG shows an irregular rhythm, no clear P waves visible, narrow QRS complexes, ventricular rate around 140. Three questions. Answer below before scrolling through anyone else's replies. 1) what is the most likely diagnosis. 2) what is the single most important thing you need to check before deciding on rate control versus rhythm control. 3) does his blood pressure change your immediate management, and if so how. I will reveal the full answer and teaching points on Friday. Tag a colleague who would enjoy working through this with you.