Hi Miranda
I also have a bad RCA. It is "congenitally small and insignificant" as stated in one cath report.
My question is why were you originally prescribed beta blockers for your anomalous origin of your RCA? Do you have symptoms from your RCA origin?
I have taken BBs for 6.5 years. I have tachycardia (pathological rapid heart rate) and high BP. I took atenolol (an older generation BB) for 6 years and really suffered from fatigue, but was told and read that all BBs cause this. Well about 6 months ago, I got really sick and my cardiologist thought that I had developed drug induced Lupus from atenolol. (atenolol is on the list of drugs that can do this).
I changed to the BB most recommended for heart failure,
Coreg, (which I do have diastolic dysfunction, and possibly Diastolic Heart Failure).
Coreg is a newer generation of BB and it has less of the fatigue side effect, to me. It also is "good for" the arteries. It does however have a reputation for making people dizzy for the first month or so. You have to be very careful. I still stagger a bit, lol.
I understand why BBs cause fatigue, depression, weight gain and other side effects such as an increase in blood glucose (a bit). BBs also cause reduced blood circulation, especially in the extremities, and can cause exercise intolerance. These side effects are not experienced by everyone that take them, but many do.
It is because of what BBs were "built" to do.
They take a load off of the heart by decreasing the heart rate, and by decreasing the force of the contraction of the heart muscle (beat). This lowers heart rate and BP. I had a heart attack and stroke in 2003 and will have to take some type of BB for the rest of my life. I don't plan to run any races though, lol.
Did you know that doctors (non-cardiologist) prescribe BBs to people for stage fright? If you have ever done any public speaking, you may remember how the heart can start racing, which can cascade into an anxiety attack. BBs prevent the racing heart, and possibly an anxiety attack.
I think Bob had a great idea; can you try another drug?
Remember that almost everyone that takes a large enough dose of any beta blocker will have side effects. Some BBs "fit" better than others. They are not the most popular medicine, but people like myself know that we need them to survive. I was always too afraid to try another type because of an incident I had when I stopped atenolol abruptly. The following 9 days were he**, and the heart attack and stroke (simultaneous) happened about 6 weeks later. I only stopped them for 4 or 5 days but my BP and heart rate was unimaginable even after I started it back for awhile.
Remember to never abruptly stop a beta blocker that your body has become accustomed to. It can cause the sympathetic nervous system to go hay-wire. Your BP and heart rate can swing wildly and cause a heart attack and/or stroke. You must slowly wean off the BBs under the direction of a doctor. (broken record here

)
Happy New Year