The default ECG lead that you can record with an apple watch (ECG supported apple watch) is lead 1, this video explains how to record lead 2, lead 3 and other chest leads using your apple watch. It can be helpful if you are a doctor who owns an apple watch from series 4 on wards in diagnosing MI (myocardial infarction)/ heart attack. Apple watch ECG ECG apple watch Apple watch ECG vs real ECG 0:00 Apple watch to detect MI or heart attack 0:52 Lead II - apple watch ECG 1:00 Lead III - apple watch ECG 1:13 Chest lead - apple watch ECG #applewatch #ecg #lead