Hi Lynn, and welcome! As somebody who did not have any heart electrical issues at all before surgery, I didn't notice any difference in my physical abilities after getting the device. In fact it was four months before I even thought to research what did I need to know about pacemakers*, the valve replacement having been the 'main event'. I do, however, notice a significantly increased heart rate when I go over particularly rickety tracks at speed on the London Undergound**, or when I am hammering or something, as the 'rate response' gets confused with all the movement. But I only l notice this because if I focus I can hear the mechanical valve ticking away rapidly - I don't experience any physical impact.
I am probably lucky in that I am a gadget person: even an electrical test engineer, conducting a routine safety test on my house's electrics recently, commented about how many multiblock extension leads I have to run everything! This means that I am not worried about being dependent on an electronic device. At my first pacemaker check-up I asked the technician how I would know if the battery was running low (not that I expect it to get that far - the annual check-ups increase in frequency as you get closer to the expected need to replace it). He kindly set it into this mode and told me to walk down the corridor to see. My heart just felt heavy, as all the advanced functions had been turned off and it was just set in a basic mode to maintain the same rate all the time.
I have developed some A-Fib, which is annoying, and does now reduce my energy levels. This can be caused by the heart surgery, the pacemaker, and being overweight, so having all three there's not much I can moan about now. The Cardiologist and the Pacemaker guys don't seem that concerned, and after a long, stressful period of intense work I am hoping to lose some weight now and see if that helps.
Although I always carry my Pacemaker ID card when I fly, I have never had to show it, and just go through the security arch like everyone else. No ill effects on me, though I do occasionally trigger the sensors but whether that is the pacemaker or something else is not clear.
Finally, for me the scars of both the OHS and pacemaker surgery were a regular reminder of what I had been through, and so once the skin had sealed (6 weeks-ish afterwards) I rubbed Bio Oil into them on a daily basis for a good few months. The pacemaker scar is almost invisible, and the 8" chest incision not far behind.
*
Pacemaker Club is a useful site, if you haven't found it yet
** The northern end of the Piccadilly Line, a service that runs with trains that are over 40 years old in tunnels built 115 years ago, is the culprit - but quite fun too!
