In 2020 alone we will collect more high-dimensional health data than from the beginning of history to the present day combined. Given the improving sensors on the wrist generating high-dimensional data (heart beat, ecg, perspiration, blood oxygen, motion, vibration, body temperature, etc), and a sample size of 100M+ people, is it not possible that there is some previously unknown signal in there that could be detected by deep learning?

I'm not saying there is, I just wonder if heart attacks might cause some discernible but very complex pattern visible in high-dimensional data that we haven't discovered yet, or if there is just too much physical distance between the wrist and heart to drown out all signal.