Doubt it, it's pretty basic technology. You can't really pull anything meaningful out of the type of sensors they use. They're much closer to Garmin type HRM quality than hospital grade ECGs with 5 (?) electrodes.
Even then, when I had my screening[1] thanks to Cardiac Risk in the Young[2] I had a proper ECG and an ultrasound (echocardiogram) to check valve operation and flow. That's not something you can do on a pitch. When the cardiologist discussed the results with me (all good thankfully) I had one concern about a very high HR I sometimes see playing 5-a-side (over 205bpm, usual HR
max is ~190bpm). He offered to fit a Holter monitor for 24h or longer to get a better picture but we decided it wasn't really worth it.
Players like Fabrice Mouamba had all of these types of scans multiple times a year and he still suffered his problems. The scanning that is done does rule quite a few players out each year (mostly for HCM) but it's far from perfect. A simple HRM like the ones the players wear now isn't going to catch anything missed by those scans.
1.
https://www.c-r-y.org.uk/screening/ 2. Oh to be under 35 again.