Hello phq

While I do not have an Apple watch, I do have a Withings smart watch which records information about heart rate, exercise, etc. I wear my watch on my left wrist. I also have a biventricular pacemaker with a defibrillator (St. Jude, Abbott) which I received in 2022.
I have never had any problems with the watch vis a vis the pacemaker. I do not, however, wear it at night but not because it gets too close to my pacemaker. It is just kind of uncomfortable. I never give it a second thought because I have had absolutely no issues with it.
I drive an EV, walk through airport security, retail security, use an induction range - although I refrain from laying on the range top because that is tempting fate. 😉 I take electro acupuncture treatments (bum knees), have regular mammograms (probably not your issue), and again, with no issues whatsoever.
But I agree with jc76, for your added peace of mind, do check your manufacturer's website. As I recall, Medtronic has a very informative site.
Modern pacemakers are built for modern living, including most if not all, of the electromagnetic fields we encounter in day-to-day living. I have sort of forgotten I have mine because, outside of the scar, I don't really know it is there.
Best wishes for a speedy recovery. And welcome to the club. There are a lot of us out here.