Flacainide

I have paroxysmal afib and am on propanolol 60mg. When I go into afib I take 100 flac. It stops usually after several hours. The thing is my HR stays steady in the normal range but my BP drops, sometimes the systolic going below 100 even after afib stopped. Is this to be expected

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alfrae13
I have paroxysmal afib and am on propranolol 60 mg. When I go into afib I take 100 flec. It stops usually after several hours. The thing is my HR stays steady in the normal range but my BP drops, sometimes the systolic going below 100 even after afib stopped. Is this to be expected

Per this review article, "During chronic oral therapy, flecainide has minimal effects on blood pressure..." About 1/3 way down the article. Chronic oral therapy may be different than using it on demand??? Or with the propranolol.

I've used flecainide on demand for over 17 1/2 years at a dose of 300 mg. This is without any other meds. I don't take my BP during an episode, so have no personal data on this. I do not experience any symptoms of low BP (like being light headed). My blood pressure is commonly < 110/60 and it is not unusual for my systolic to be less than 100 mmHg (again without symptoms). I have never taken BP meds.

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alfrae13
I have paroxysmal afib and am on propanolol 60mg. When I go into afib I take 100 flac. It stops usually after several hours. The thing is my HR stays steady in the normal range but my BP drops, sometimes the systolic going below 100 even after afib stopped. Is this to be expected

I wouldn't say it's normal exactly, but it's probably also nothing to be alarmed about.

When your BP drops like that, do you experience symptoms such as dizziness, lightheadedness, or feeling weak? If not, then don't worry about it. It's just a quirk of how your body reacts and isn't harmful or dangerous.

While in afib, my BP (usually 110 syst.) is lower (90-100). No meds. I'm used to, and it's short duration without dizziness. I've just to take care not standing up suddenly and making other fast movements like that.

Nothing to support this, but while in afib, with the lack of regular strong heart beats, it would seem that blood pressure would drop with the reduced blood flow while in afib. You can be lightheaded while in afib due to the reduced flow of blood and O2 to the brain and body.

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Ken
Nothing to support this, but while in afib, with the lack of regular strong heart beats, it would seem that blood pressure would drop with the reduced blood flow while in afib. You can be lightheaded while in afib due to the reduced flow of blood and O2 to the brain and body.

Here is a review article supporting what you are saying, Ken. [www.nature.com]

"Conclusion
Manual measurement should be used where possible for measuring blood pressure with atrial fibrillation. Limited data exist to suggest that some automated devices can accurately measure systolic, but not diastolic, blood pressure in the presence of atrial fibrillation. Further work is needed to evaluate the many commonly used devices lacking such data. Future comparisons should follow internationally recognised protocols to ensure validity and facilitate comparisons."

(Nothing to support this, but while in afib, with the lack of regular strong heart beats, it would seem that blood pressure would drop with the reduced blood flow while in afib. You can be lightheaded while in afib due to the reduced flow of blood and O2 to the brain and body.)

All I can say is this is not true in my case. My BP is not low, it is always high in the doctors office and at home my Systolic is usually anywhere around 120 to 150, depending when I take it. But it is never real low. George by manual measurements -- are you saying that they will be more accurate for people in AF if taken with an Automatic Blood Pressure Monitor, I have one by Omron, for me, will that be the most accurate?

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Elizabeth
George by manual measurements -- are you saying that they will be more accurate for people in AF if taken with an Automatic Blood Pressure Monitor, I have one by Omron, for me, will that be the most accurate?

No, my understanding is they are suggesting taking the BP with a stethoscope & listening. In the article, they mention certain machines that have been tested to be accurate, but in general, they suggest using a cuff with a stethoscope.

I very rarely take my BP during afib. It so happens that my very first afib was noticed because I was taking my BP with a stethoscope. My BP was fine, but I'd never heard my pulse sound like that before. I think I took it again sometime in 2021 and noticed again how unusual my pulse sounded in afib. I've always used a manual cuff with stethoscope and have never owned an electronic BP monitor.

As Ken and the article point out, when I look at a pulse wave using a fingertip plethysmograph pulse wave monitor you can see a large variation in the amplitude or height/strength of pulse waves. I think it could be difficult for a machine to figure this out.

Oh, ok, thanks George. I wonder how far off my BP readings are, when I take it with my home monitor machine..

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Elizabeth
Oh, ok, thanks George. I wonder how far off my BP readings are, when I take it with my home monitor machine..

It is a good question. If the monitor is not sensing the soft beats, it could be reading high. You can see how irregular the pulse wave is by feeling your radial pulse with your finger(s) on your wrist, neck or other pulse point. I know that mine did have a lot of variability and I seem to recall that there were many more "soft" beats than hard beats. For example, taking your wrist pulse then slowly reducing the pressure of your fingers on your artery, you could get a sense of the beats that are missed. If the time between "hard" beats is longer, then the likely hood of a too high pulse is greater, especially depending on how fast the machine inflates or deflates (depending on when it measures.

BP readings taken manually by someone trained to do so correctly are always more accurate than machines, and that's especially true during arrhythmias. A human can hear the irregular pulse and judge it more or less correctly, but it completely confuses machines. A machine might get your systolic pressure approximately correct during afib because all it has to do is identify the first beats it can hear, but it will probably be very wrong about your diastolic because that requires detecting when the last beats were audible, and the long gaps during afib can fool it.

This is a lot like all the consumer-grade sports heart rate monitors out there. I haven't found one yet that can correctly count a heart rate during afib, or even during periods of a lot of ectopics. I've seen some pretty amusing numbers from my Polar chest strap monitor.

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Carey
I've seen some pretty amusing numbers from my Polar chest strap monitor.

Curious if your Polar device records beat to beat? What gets displayed on the watch or a phone app getting data from the strap is always averaged. However the recorded data are excellent. Not in afib, they also will pick up PAC's or PVC's. Years ago (maybe 2005) I figured out how to tell the difference. I hooked up a DIY recording ECG I'd constructed along with a Polar strap and beat to beat recording watch, then compared the signature for PAC's & PVC's in the recorded data. I learned the strap doesn't "see" the malformed PVC beat ECG signature, so will report them as a half speed beat (compared to the surrounding beats) - also means RR time was twice as many milliseconds. I've found very few devices or apps that will record the RR data. The app I use is built for exercise physiology research, so not many consumers use it. However it gets its data from a Polar H10 or H7 strap.

With all the years of looking at the averaged data on the app or watch during afib, I can tell when I go from afib to flutter or convert to NSR.

I have no idea how it records beats. I never cared enough to ask that question. I just know that it does so highly inaccurately during afib and periods of lots of ectopics. But not flutter, presumably because flutter is a regular rhythm.

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Carey
I have no idea how it records beats. I never cared enough to ask that question. I just know that it does so highly inaccurately during afib and periods of lots of ectopics. But not flutter, presumably because flutter is a regular rhythm.

Ah, now I understand why you aren't a fan. Unless you specifically look for a device or app that will record beat to beat, they all average. I've looked for these devices for 17+ years. The original Polar that would do this was the s810 followed by the s810i, their most expensive, of course. The replacement was not nearly as easy to use. I migrated to an iPhone app (with a Polar H10 strap), Heart Rate Variability Logger around 2014. I still use the obsolete Polar software to view the data as it has superb ability to window the data quickly.

I also have an SpO2 ring that records heart rate every 4 seconds. While fine for most purposes, it is much less useful for heart rhythm issues. About the only way to tell afib is the average heart rate increases in me, but that could be for lots of other reasons.

In this post I was capturing data with both the ring and with the app when afib initiated and during the conversion. In the post the first two images are from the ring data every 4 seconds (SpO2 on the top of the graphs and HR on the bottom). The last 3 graphs are beat to beat heart rate from the Polar data. A vast difference. The afib episode was terminated with an exhaled breath hold and only lasted about 3 1/2 minutes. In the first Polar graphs, the upward spikes on the chart before the afib are PAC's. If you look at the afib section of the Polar graphs, you can easily see the characteristic beat to beat variability of afib.

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GeorgeN
Ah, now I understand why you aren't a fan. Unless you specifically look for a device or app that will record beat to beat, they all average.

Actually, I forgot that I replaced my Polar chest strap several years ago with a Viiiiva 4, and it does record beat to beat. But with afib, it also produced inaccurate results.

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GeorgeN

I've used flecainide on demand for over 17 1/2 years at a dose of 300 mg.

George weights more than 154 pounds so 300mg flecainide within a 24 Hour period is the maximum dose. If you weigh less than 154 pounds then 200mg within a 24 hour period is the maximum. I had a flecainide overdose and almost died in the icu so I keep posting flecainide dosage warning for those who don’t know. It’s not a drug one experiments with.

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susan.d


I've used flecainide on demand for over 17 1/2 years at a dose of 300 mg.

George weights more than 154 pounds so 300mg flecainide within a 24 Hour period is the maximum dose. If you weigh less than 154 pounds then 200mg within a 24 hour period is the maximum. I had a flecainide overdose and almost died in the icu so I keep posting flecainide dosage warning for those who don’t know. It’s not a drug one experiments with.

I remember that you had a Flecainide overdose and nearly died, but I don’t remember what exactly happened? I ask because a couple of months ago I had complete heart block from Flecainide and I wonder if this is what happened to you. Luckily I had a pacemaker in place, but I certainly agree—Flecainide is a tricky drug. I had been taking it for years but had recently had my dose increases to 150 mg twice daily which was obviously too much for my 135 lbs.

Daisy-
[www.afibbers.org]
[www.afibbers.org]

Every drug has side effects and that shouldn’t deter anyone from being scared to take a drug. Just be careful and don’t experiment and get the blessings from both your EP and pharmacist who knows what other drugs and supplements you are taking that could cause a CYP3A (cyp450 family) inhibitor interaction.

I recommend a flecainide serum blood test. It helps determine what strength you need by how much flecainide is metabolized in your liver (enzymes) and possible kidneys that could result in causing flecainide to remain longer (inhibitors) in your system. Labcorp does this test.



Edited 1 time(s). Last edit at 05/04/2022 03:25PM by susan.d.