Anyone on Carvedilol for A-Fib?

I've been on beta-blockers for the last couple of years for a-fib, first bisoprolol, then switched to metoprolol (100 mg/day).  I am otherwise healthy (age 52).  I've gained over 20 lbs over the last year - but particularly since the medication change last fall (which I need like a hole in the head).  Eating healthy and working out does nothing - as a matter of fact, I feel like I'm still gaining.  I started doing some looking online for any kind of helpful information and have found several articles saying that studies show that Carvedilol doesn't cause the weight gain that Metoprolol can.  I'm not even sure that this particular drug is appropriate for me, but I'm wondering about anyone's experiences with weight gain and Carvedilol vs Metoprolol, and also anyone who is being treated with Carvedilol for paroxysmal afib.  I have an appointment with my cardiologist in 2 days and I'd really like to discuss this with him.  ...Thanks for any help!