Yesterday, I took a pre-op physical. I got "flagged" on the ECG because of an apparent "electrical blockage" pattern, I'm not an expert, just a patient!. My first clue was the tech asking me if I felt ok as I was getting up from the procedure. The second clue was the nurse entering the data saying that I would probably have to see a cardiologist prior to the operation. (I feel fine, no symptoms of anything). She showed me the ECG and instead of a sharp spike for the heartbeat, there each spike has a little dip in the center. This, she said, indicates an electrical blockage that often happens with older patients. Not life-threatening, but worth a closer look. We checked my health app on the iPhone and, sure enough, that pattern has been there for several months. This is an EASY pattern for even a novice (like me) to see IF we know about it. I don't expect the Apple Watch ECG app to do what happens in a cardiologist's office does, but this one is a no-brainer pattern that should have at least been brought to my attention. (Non-life threatening, but get it checked). This is the graph from my own watch. Notice the little dip in the top of the spike. Apple should be easily able to detect such a patter and give a notification. Again, I'm certainly not an expert, but this seems like something the watch was obviously catching (for months) and had I been notified, I could have had it checked before the pre-op exam. Now my surgery will be delayed as a cardiologist doesn't take walk-ins. The tech and the nurse were amazed that the watch has "seen" this unusual pattern. They watched me take an actual ECG on the watch and could see the dip on the face. Then I pulled up the historical ECG graphs in Apple Health and there it was for months. What the watch detected was AMAZING (Kudos Apple!!), that it remained silent on something so obvious, is DISCONCERTING. What else does it know that could save a life?