I'm going to sound like a skeptical jerk here, but 490,000 heartbeats is how many patients? From what I recall these public ECG datasets are like 20 patients who underwent longitudinal ECGs. 500k heart beats is like 5 person-days of ECG recordings. Ninja Edit: N=~30 patients. For something like ECGs which are readily available, they really should have tried to get more patients. A single clinic anywhere does than 30…
Well you're on the right site for it!
At least you didn't claim that you could come up with something better by tinkering on a rainy Sunday afternoon.