Had one put in a couple of months ago. Went to hospital for Atrial Fibrillation attacks that were getting too frequently and for too long. After tests all day, went to bathroom that night and passed out when heart rate dropped to below 30, adn then the damned thing stopped beating for 24 seconds.
They decided it might be a prudent idea to insert a pacemaker! I agreed. 
The procedure was surprisingly simple, under local with some tranquilizer, felt nothing but a sort of pressure on my chest from the surgeon’s hands. They just cut open a slit on the chest below the collarbone, and slip it in, but then have to snake a couple (in my case) wire leads down into the heart and sort of screw them into the inside of the heart.
All together it only took about an hour. In my case, it was just to control the minimum heart rate. To make it do the maximum too, it may be more complicated, but doubt it, as they can program the thing, once inserted, to do almost anything by just placing a gizmo on the chest and then using a laptop.
It was a bit sore to the touch for about a month. For the first few weeks you are not allowed to raise your arms above your shoulder, or obviously, do any strenuous lifting. Refrain from boxing or wrestling alligators. 
Now when I do upperbody dumbbell weight work, it gets a little sore, but nothing to worry about. They will provide printed info on what to avoid, but much different than it used to be. The titanium case shields it much better, but still best to keep away from running microwave ovens just in case. They put it on the opposite side from the hand you use most, so cellphones should always be used on the opposite side of the pacemaker too, which takes a while to remember.
My device was a Medtronic, and they gave me a little booklet that gives a vast amount of info. You can Google “pacemakers” and find a wealth of info.
All in all, there are a lot worse things they can do to you, I have no problem with it at all now.
If you have any specific questions, you can email me (address in my profile), but much better to write down all questions and then ask the cardiologist.
Good luck to your bro.