hi, my cardiologist has told me to get a ECG sensor to record any SVT attack’s I may have, I’m in the UK so the choices appear to be a bit limited. I looked at the Alivecor Apple Watch Strap (I have a series 1 42mm), but discounted it as it doesn’t seem to be available in the UK and has a monthly subscription charge. Are their any other watch strap ECG readers available? If not is the Apple Watch S4 any good at recording SVT? Can you email the readings it collects and can it take several readings in an hour say? Is it reliable at recording?