Atrial Fibrillation, Running, and Beta Blockers Part Two


The last article I wrote about beta blockers was written last Summer when I was more or less just starting the beta blocker. I had noticed a decrease in performance and exercise tolerance and when I went to the cardiologist and had an echocardiogram it was determined that my rate was going up and my ejection fraction was going down – that means my heart was pumping less efficiently and was pushing out as much blood with each beat. I was put on a low dose of carvedilol (6.25 mg twice daily) and it was thought that this would allow my ejection fraction (EF) to come back up.

When I started my EF was 55%, but when I had the echocardiogram mentioned above it was down to 45%. As noted in my last beta blocker article I suffered on runs and bike rides but felt it was worth it as I anticipated improvement.

When I returned for the follow-up echocardiogram I was extremely disappointed to learn that my EF had actually gone down to 37%. Not good.

At that point I the dosage of my beta blocker (carvedilol) was titrated up from the minimum dosage to the maximum dosage (50mg twice daily).

As you might imagine between the atrial fibrillation, the decrease in EF, and the high dose of beta blocker – running became extremely difficult. All three of these things decrease my cardiac output and, of course, that translates to poor performance. I now found I had slowed to a ludicrous pace, and honestly, running was starting to become a chore.

Running was starting to become unenjoyable; but I continued anyway.

I felt like every run was my first run after not exercising for several years, and I was walking up the most minor hills.

Last week I returned to the Heart Clinic and had yet another echocardiogram. To be honest I haven’t been feeling any better and runs still seem difficult so I decided not to even look at the screen or ask the tech about my EF as I assumed it was still poor. I’d just wait until the follow-up appointment with the cardiologist. But the tech, who knows me by now, just came out and told me – “Well, it looks like your ejection fraction is improving – it’s up to 47%.”

Well, that is good news. At least this suffering through the beta blockers is leading to some benefit.

That was just the preliminary reading, my new cardiologist (my previous cardiologist retired from clinic but still works at our hospital) interpreted the echo and said it was more like 50%!!! That’s nearly back to normal range (52-70%).

One interesting thing the cardiologist told me: she said that one would expect that people who are more athletic would have higher ejection fractions than non-athletes but in reality the opposite is often the case. I told her that my heart is so big that if my ejection fraction was too high there would be too much blood – ha ha.

hot lava

There’s something I don’t understand about echocardiograms and atrial fibrillation – as anybody who is in a fib knows some beats are better than others. It’s easy to feel that – some are short and weak and others are longer and more powerful. How, when looking at the heart with the echo machine, can you tell what kind of beat you are having?

So there is some good news. Runs are still difficult and I don’t see myself ever being completely off of the beta blocker – but hopefully a different dose in the future when my ejection fraction reaches whatever the goal value ends up being.

In my next article on running and beta blockers I will discuss “Beta Blocker Blues” and the way this unpleasant medication makes me feel fatigued and, often, quite depressed. But for now I’ll embrace the joy of knowing my ejection fraction is significantly improving and will likely get even better.