A fib, low hr, not showing up on fitbit

16 years ago, I had aortic valve replacement, a maze procedure and they sewed shut my atrial appendage. I was afib free until recently.

I have had a Fitbit Sense 2 for about 6 months. It has never had an arrhythmia alert. Last week, the cardiologist said the ekg showed I was in afib. I’ve been tired and draggy, but no afib symptoms like I had before the maze procedure 16 years ago. My resting hr ranges from high 50’s to mid 60’s. I’m on metoprolol, furosemide and lisinopril for BP. I’m 6’2” and 175.

The cardiologist sent me to an ep. His ekg also showed afib. He’s scheduled me for an ablation.

Has anyone had a similar experience? Any educated ideas as to what’s going on?

Thanks.

I have never used the Fitbit so cannot comment on its accuracy. Others may be able to help you with that. I do know that I was in asymptomatic, slow rate aFib that lasted several months. BPM in upper 60’s to low 70’s. This was easily picked up by my Kardia. Maybe the EKG just happened to catch things at an opportune moment. Sorry I’m not knowledgeable to offer more.

Welcome to the forum. Yes, there's a ton of experience here. Decades worth among many, many people. And what's going on is apparently you have afib. Sorry. The big question is whether it's persistent (never stops) or paroxysmal (comes and goes). Since you've only had two EKGs done I doubt if they know the answer to that question, and it's a very important question. You should be put on a Holter monitor first to answer that.

When is this ablation scheduled for? I ask because I think slowing down and evaluating your options would be a very good idea.

The absolute single most important thing that matters when it comes to an ablation is the experience level of the person doing that ablation. How many afib ablations has this EP done? Do you know? If not, you need to ask. The answer you want to hear is thousands, not dozens or even hundreds. How many ablations are performed per year at the center where it will be done? The answer you want to hear is hundreds. I can't stress enough how much this matters. I put little value on credentials such as schooling, awards, research, and achievements. Afib ablations are the most difficult, complex ablations of all, and you don't want to be the guy someone is learning on. Also, is it a teaching hospital? If so, is your EP willing to guarantee it will be only them with their hands on the ablation catheters and not a trainee? If it's a teaching hospital, it's likely it won't be the EP you know actually doing the procedure.

But let's get back to that question about paroxysmal vs. persistent afib. I'm guessing yours is persistent, but obviously I can't know and apparently neither can your doctors. You should know that if it's persistent, an ablation from the average EP only has about a 50/50 chance of fixing it, at best. I wouldn't advise an ablation from an average EP in any circumstance, but absolutely not if you're in persistent afib. It's beyond the average EP's abilities. Don't let anyone rush you into a procedure. Hang around here a while and we'll help you figure it out.

You will have to get into the manual for your particular model of FitBit. It will be available to download or to read at that website under 'Support' usually. In my fairly recent model of the Galaxy watch, it will detect AF, but it won't alert the wearer. There is no provision for that. Instead, the wearer must direct the applet to measure HR and to record an ECG. That record will then be transferred upon demand through your phone or other bluetooth connected app that manages the FitBit.

Also, a wearable would need to read your pulse continuously in order to provide you meaningful information from minute-to-minute over the course of your ever-dwindling battery charge. In my Galaxy's case, I CAN set it to continuous, but it will run down the batter in a few hours doing so. Instead, I tell it to record a 60 second ECG. Otherwise, the default is to record my HR every ten minutes, and then only when I am still...inactive.

Using the same health applet on the watch, I can tell the watch I am on a run or a walk, or some kind of activity, and it will enter into exercise mode and record my HR continuously over the duration of the event. Again, for that long, it will run the battery down more quickly than it would the 10 minute periodic.

All this to say that, unless there is provision in the engineering and software to continuously monitor your HR (meaning one helluva battery!!), your FitBit is probably only doing what it is designed to do. The manual will tell you that.

Fitbit does not analyze your EKG in real time. From their product info:

Fitbit doesn’t analyze your data in real time. If you receive a notification, it means we saw signs of an irregular rhythm that may be AFib in the last 24 hours (with regular device syncing).

Also you have to have the irregular rhythm notification turned on. Lastly, Fitbit does the analysis when you are sleeping or are still.

Thank y’all. I’ve been down the afib road before and I think I was on this or a similar forum back then.. Previously, I had paroxysmal afib and I could tell when it started and when it ended. That goes back more than 20 years ago and my maze procedure was in 2007. Whatever I have now is different. I don’t feel a thing but I’m tired and run down feeling.

I’ve had multiple ekgs in the last 6 months and the last 2 are the only ones that caught any afib. Last fall, I had a weird blood pressure spike and was in the hospital for 3 days. They never exactly told me what caused the bp issue but they found some potential pulmonary issues (a nodule on my lung and pulmonary effusion). The nodule appeared benign and I was told to follow up after 3 months. I did. After another 2 months of pulmonary tests of every sort, the nodule had gone away and was probably an infection of some sort. Even a PET scan was clear. The pulmonologist said I don’t have pulmonary issues and drained a very small amount of remaining fluid in my pleural area.

The pulmonologist sent me back to the cardiologist and that’s when they saw the afib.

Cardiologist sent me to an ep who doesn’t do anything else. He’s very experienced. He too saw afib on his ekg.

I still don’t feel it. My Fitbit Sense 2 has an ekg function and it always comes back normal. But.

I wonder if a Karelia device would be more accurate than my Fitbit? And I wonder if anyone else has ever experienced something like this.

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67walkon
I still don’t feel it. My Fitbit Sense 2 has an ekg function and it always comes back normal. But.

I wonder if a Karelia device would be more accurate than my Fitbit?

From Fitbit: [help.fitbit.com]

"Fitbit smartwatches and trackers have optical sensors that can detect the pulse of blood that goes to your wrist with every heartbeat. The Fitbit Irregular Rhythm Notifications feature collects heart rhythm and motion data to check for signs of AFib. When you turn on the feature, your heart rhythm data are collected in the background while you are still or sleeping, and analyzed for AFib when your data sync with the Fitbit app. After your consumer wrist-worn product collects enough analyzable pulse rate data, we look at your beat-to-beat measurements to check for irregularities. Beat-to-beat measurements indicate how quickly one heart beat comes after the other . It’s typically measured in milliseconds (ms) and converted into beats per minute (bpm). Normally, these measurements are relatively predictable and smooth. Big increases or decreases (over 10 bpm) in a short period of time may be considered irregular."

My interpretation is the Fitbit is looking at beat to beat variability to detect afib. It is possible that your BP meds tamp down the variability such that it doesn't trigger the Fitbit algorithm. I don't know if this would fool the Kardia algorithm. "In the study, the Kardia algorithm correctly interpreted AFib versus normal sinus rhythm with 93 percent sensitivity and 84 percent specificity. " Source

With a Kardia, you'd at least get a Lead I or II (depending on where you place the device leads) ECG. With this you could visually see if the "p" wave is absent, an indicator of afib.

Thank you!

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67walkon
I wonder if a Karelia device would be more accurate than my Fitbit? And I wonder if anyone

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else has ever experienced something like this.

I have both and the Kardia is much more accurate. Fitbit misses a lot.

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Carey
Welcome to the forum. Yes, there's a ton of experience here. Decades worth among many, many people. And what's going on is apparently you have afib. Sorry. The big question is whether it's persistent (never stops) or paroxysmal (comes and goes). Since you've only had two EKGs done I doubt if they know the answer to that question, and it's a very important question. You should be put on a Holter monitor first to answer that.

When is this ablation scheduled for? I ask because I think slowing down and evaluating your options would be a very good idea.

The absolute single most important thing that matters when it comes to an ablation is the experience level of the person doing that ablation. How many afib ablations has this EP done? Do you know? If not, you need to ask. The answer you want to hear is thousands, not dozens or even hundreds. How many ablations are performed per year at the center where it will be done? The answer you want to hear is hundreds. I can't stress enough how much this matters. I put little value on credentials such as schooling, awards, research, and achievements. Afib ablations are the most difficult, complex ablations of all, and you don't want to be the guy someone is learning on. Also, is it a teaching hospital? If so, is your EP willing to guarantee it will be only them with their hands on the ablation catheters and not a trainee? If it's a teaching hospital, it's likely it won't be the EP you know actually doing the procedure.

But let's get back to that question about paroxysmal vs. persistent afib. I'm guessing yours is persistent, but obviously I can't know and apparently neither can your doctors. You should know that if it's persistent, an ablation from the average EP only has about a 50/50 chance of fixing it, at best. I wouldn't advise an ablation from an average EP in any circumstance, but absolutely not if you're in persistent afib. It's beyond the average EP's abilities. Don't let anyone rush you into a procedure. Hang around here a while and we'll help you figure it out.

.

Fitbit/Kardia issues aside this is good advice.

IMHO if you don’t feel your Afib why rushing into an ablation? Have you tried Flecainide or other drugs? Flecainide for some can buy you time (years for some) until the pulse ablations will be mainstream and the technology of choice.

Check out the best most experienced EP you can get. Plus your hr is not in tachycardia but mild. My only regret (everyone is different) was rushing into an ablation when my hr during Afib was about 67-80 -when I was nervous before an ECV in the beginning. I ended up after the ablation with flutter, pvcs and svt- not uncommon for some because scar tissue from the burns can cause it. Many here have had their share of flutter tachycardia. It’s when that happens and you get tachycardia you wish you had your old low hr.

But everyone is different. I’m sure some readers will post their suggestions. I suggest don’t rush into it. Ask the EP how many ablations he has done plus the questions Carey suggested and investigate drugs to buy some time.

Best of luck with your decision.