Case: 62 year old man attends emergency department with shortness of breath and recurrent episodes of syncope. He is known to have chronic obstructive pulmonary disease (COPD) and has smoked heavily for 40 years. All we know about his medications so far is that he takes something for his blood pressure and has inhalers for his COPD. He does not normally require O2 at home. He is currently pyrexial. His blood pressure is 110/70, he is normally hypertensive. He is tachycardic with an irregular pulse. Arterial blood gas shows a mixed respiratory and metabolic acidosis. His saturations are 85% on 15L of O2. You do an ECG which shows the following: I have provided a case to go with this ECG for completeness. What does this ECG show? (Please click on the image to see it in full size).