In early October 2024, after a strenuous run, I had an AFIB episode for 20 hours. I went back to normal sinus rhythm on my own. I had a visit with my cardiologist within a day. My options at that appointment were another ablation or going on an antiarrhythmic drug; I chose the latter.
He prescribed 50mg of Flecainide “just in case.” I took that as a pill in a pocket to take if I went into AFIB.
I filled the prescription. At the same time, I reduced my Metoprolol dose to 12.5mg twice a day.
I stayed in normal sinus rhythm until late January when I had another AFIB episode for 20 hours. At that time, I took five 50mg doses of Flecainide, 12 hours apart, increasing my Metoprolol back to 25mg. I saw no cause for the issue and came out within a day. On the second day, I skipped the Metoprolol as my blood pressure was too low to take it safely.
The third morning, I took regular doses and went out for a run. I almost collapsed within my first 60 strides and had to hold on to the median sign while crossing Chatham Heights Road. I reverted to walking with a few little jogs. I could not get my heart rate above 100. Since I was back in normal sinus rhythm, I stopped the Flecainide and reduced my Metoprolol to 12.5mg.
Twenty days later, I had a previously scheduled follow-up with my cardiologist. My two options were an ablation, “we might have missed a spot,” or taking 50mg of Flecainide and 12.5mg of Metoprolol twice a day. If the drug option did not work or impacted my running, we could revisit the ablation option.
I did not start the new routine until after finishing the Dahlgren Trail half-marathon the following day.
One of the advantages of running the same courses daily over multiple years is that I have a lot of comparison data. I’m two weeks into the experiment.
Before the change, my average heart rate on my usual 3.5-mile loop was 125, with a maximum between 135 and 157. My half-marathon average rate was 122, with a 166 maximum. My sleeping heart rate was around 60.
Metoprolol is a beta blocker and does reduce heart rates. Flecainide is not supposed to have an impact on heart rate.
After the change, I’m finishing in the same time frame on the 3.5-mile loop. I feel the same effort. However, when I take walking breaks, my breathing is more labored. My sleeping heart rate has dropped to 55 to 59 bpm. My running average heart rate is 113 and usually peaks at 125; for some reason, today, my average was 115 but maxed at 140.
Here are a couple of charts to reflect the changes. Day 0 is the date I started taking Flecainide. The minus days are before the change, and positive day numbers are after.
My running pace is about the same regardless of the run’s distance. However, my perceived effort feels more difficult in the positive day range.
I take my blood pressure in the morning within 30 minutes of waking up and again before dinner. I follow this procedure to ensure I can take the Metoprolol. Along with reporting blood pressure, a calculated pulse is also reported. I wear my Garmin at night, recording my heart rate while sleeping. You can see post drug change, all three are dropping.
My Gramin reports an average and maximum heart rate while running. I use a chest strap to get a more accurate reading. These numbers are down, too.
Since my ablation last April, it takes me the first half mile to warm up before running more than a quarter mile without stopping. During the warmup, I run 30 paces and then walk. I’ve only had one repeat of the almost collapse issue. I’m cautious about running across some of the major roads.
So I wonder, does anyone else have experience running with this drug combination?