Hi there. This may seem to be a stupid question but if you've been diagnosed as having asymptomatic AF, how can you NOT FEEL your heartbeat racing at what feels like hundreds of miles an hour and it's going to jump out of your chest? 🤔. Or is the simple answer that nothing appears to be any different at all for you? (Maybe I've just answered my own question!) Doesn't your heart race at all? How can it be diagnosed if no symptoms are being shown?
I've been diagnosed as having paroxysmal AF and it seems impossible to me that you can't feel your heart racing and having palpitations, as my symptoms seem to be quite severe.
Lily
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MrsSuzuki
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Now, that's an interesting question. Here is how I see it, after decades in the field of hydraulic power transmission.
When in NSR, the heart pumps the blood efficiently and, when resting, at say 60-70 bpm. When we start exerting ourselves, the body needs larger blood flow-rate, so the HR increases until the output equals the demand. If the exertion is small, it will stop at 120 bpm, but if it is very large, HR will stop at say 180 bpm. There is almost linear interdependence between the flow-rate and the HR. Actually, at high HR, the chambers have no time to fill with blood as it should be, so the flow-rate gets slowly smaller than directly proportional.
When in AF, there are two scenarios.
In the first one (symptomless), the heart is structurally such, that it easily starts working in the new regime, whereby the ventricles work without help of the atria (even with some disturbance from their side). Such heart pumps relatively efficiently in AF regime, so it gets to the demanded flow-rate at say 80-90 bpm (my case and the case of many others here), or at 120 bpm, or even 160 bpm. This relatively low HR makes it possible that the ventricles suck the blood sufficiently and provide sufficiently large blood flow-rate.
In the second scenario (with severe symptoms), the heart is not capable to work with large enough efficiency, so in the course to achieve the demanded flow-rate, the HR gets increased very much, causing still smaller EF, and, in an attempt to make the things better, the HR goes very high (often above 200 bpm), whereby the blood flow-rate (and the BP) goes down, the heart itself remains without enough oxygen, and people have unpleasant symptoms.
The numbers given are just for illustration and, of course, differ from patient to patient. If my English was a little better, my post might have been shorter, lol!
People do get used to their heart doing odd things when it is constant. When it is paroxysmal, the switch between NSR and AF is what is so noticeable and becomes most uncomfortable.
Many people in permanent AFare quite unaware that they have it at all and sadly many only find out when the stroke hits them.
I was very symptomatic when having episodes of paroxysmal AF and never thought I’d be able to operate at all if I had AF all the time. However, I have been in persistent AF since February and it’s been fine. For the majority of the time I don’t even know I’m in it unless I check my pulse. The only thing I can think is that, as the AF is happening continuously now, my body has adjusted to the decreased pumping efficiency of my heart. The only time I notice I’m a bit breathless is if I’m doing something that requires a continual sustained effort, such as walking uphill.
I'll just tell you how my AF kicked off. I woke as usual but didn't feel 'right' - planned to go to work but didn't as I felt even more unwell. Took blood pressure and it was normal at around 136/80 ish. As the morning went on I felt I was going down with flu. By mid afternoon, gradually feeling worse I clocked my BP again and it came in at 76/50 ..... my Apollo 13 moment ( the bit in the movie when Tom Hanks says - Houston, we have a problem ). I phoned my GP then and he said come and see him immediately - which I did and he sent me directly to A & E.
After arrival at A & E I was diagnosed with paroxysmal AF and my HR was clocked at 156 bpm ( might as well have been 156 mph ) - felt bloody awful by now. I was then kept in Cardiac Ward for another 5 days. At the end of my stay my Cardiac Consultant wrote to my GP referring me back to his care .......... in part of that write up to my GP the Consultant wrote specifically that I could be in paroxysmal AF and not have any symptoms !! In other words, asymptomatic. My point is that at 156 bpm/mph I didn't feel anything other than I was going down with flu. It was only in hospital that something definitive was picked up.
As far as I know AF can be detected with a number of devices, none the least of which would be an ECG or an Echocardiogram .... even if the patient isn't feeling a thing. If you have this sort of scenario and you don't feel anything then it will be detected with the correct technology. These days if I feel strangely off colour I self monitor with my blood Pressure monitor and my Kardia 6L.
Thats why I am a strong advocate of taking your medication as prescribed, whatever is in your party bag of drugs for AF, if you are asymptomatic and have an AF event, and don't know it at all then you are playing Russian Roulette with, potentially, your life. You just cannot assume that because you feel nothing you are not having an AF event.
My AF is usually triggered by exercise if my HR exceeds 145 ish. I wear a Garmin watch and regularly check whilst running. I only realise I’m in AF when I check my watch and see my HR has shot up to 210+ (Last time it was 225). At that point I stop running and walk home. I suspect if I kept running and hadn’t realised, after maybe 10 mins I’d start to fatigue and clock it but other than that, I would not be aware.
Several times I’ve had spontaneous episodes (none exercise related) and only realised when something prompts me to check my pulse. I suspect in these circumstances, I’ve probably been in AF for several hours before I realise. It will however be around 105 so not that fast. I’m not normally however able to sense my pulse (occasionally when lying down I can feel it pulsing in my ear) whereas others maybe able to sense it normally and so notice when it’s racing.
Good descriptions here I think. My resting HR is about 85 BPM. Going up to peak at about 160 when exercising (according to the Fitbit anyway).In that regard due to possibly diminished ability to convert air into oxygen in my blood there is ultimately a limit to what I can do.
It's fairly obvious (in hindsight) due to its irregularity in my pulse and was originally picked up by my Dr when using his stethoscope for a different reason. Then properly confirmed later by ECG. I don't feel my heart is leaping out of my chest for which I am very grateful, but neither do I ever get into NSR, at all.
I was asymptomtic. I only knew I had AFib owing to my Garmin watch. I had 243BPM running and had could not tell until I looked at my watch . Yes I did stop until it dropped.
I’ve suffered with permanent AF and then paroxysmal AF after ablations and it’s MUCH easier to deal with permanent AF from my experience. Before diagnosis, I thought my racing heart was due to being a busy working mother - always rushing round with to-do lists in my head. I was (unbelievably) running 5 times a week although found it increasingly hard to run each time. When I was diagnosed, my aunt with paroxysmal AF would say she didn’t know how I dealt with it but I’d feel “fine” but I didn’t know anything else as it had crept up so slowly and become part of my life. Now when I have episodes of AF, I feel truly awful and can’t believe I had this all day, every day and could bear it more easily….
My AF was paroxysmal for about twenty years. The medication, Flecainide in my case, reduced the number and length of episodes to one or two short (10-20munutes) episodes each year.At an unknown time between two annual consultant appointments my heart went into asymptomatic persistent AF. That was about six years ago,
I can't feel my AF, unless I feel my pulse.
I used to get out of breath walking, (I am also asthmatic), but since I lost 2 stones in weight, I don't get out of breath any more.
The only medication I have because if AF is an anticoagulant, Warfarin being my choice.
When my AF was paroxysmal, I didn't know my heart wasn't working properly. I just felt unwell - like I was about to go down with a virus. I described it as feeling like I was running on empty - but I could still do everything I needed to do. It was only when I started suffering syncope (passing out) that I got diagnosed and pretty soon after that (days) my AF became pretty much persistent.
I guess it’s because we are all different - I had an episode last night, my first for nearly 2 years, and I knew immediately that my heart was out of rhythm - my chest feels like frogs are jumping all over the place - my Kardia readings confirmed that I was in AF
For the first time my HR did not go over 100 but the symptoms felt the same
I had just taken a quinine tablet for severe cramp but I’m guessing that might have been the trigger
I took my PIP meds (bisoprolol) and I converted back at 6.00am after a night of discomfort and panic
Again I knew immediately when I went back into NSR as the frogs stopped and the Kardia confirmed it
I have friends in permanent AF and they have no symptoms
I was diagnosed as having paroxysmal AF when in hospital for another procedure. For several years I had no symptoms at all. I guess it was a lucky find, which meant I could take anticoagulants as a precautionary measure.
It's a common question on the forum. It's important to note that in a good percentage of those with AF there is no raise in pulse rate.
It seems clear that persistent AF gradually models the heart to the point (in layman's terms) at which it accepts the chaos, stops objecting and quietens right down. In fact many people don't even go through that process because they are never symptomatic. I have two friends with long-standing permanent AF and both say they wouldn't know if they hadn't been diagnosed. They take their medication and other than that are unaffected.
I have Paroxysmal AFib and when I get an episode, I know immediately, as my heart goes very fast, over 160 bpm, it doesn’t beat properly and my blood pressure rises. I’ve been told by Doctors, to go into A&E if it occurs, as they like to keep an eye on me. I usually get put on drips and given medication I’m awaiting a catheter ablation, due on 20th September, but have just heard all the Doctors are going out on strike that day, so I’m expecting to get a letter, saying it’s cancelled.
Hi, interesting question cos using this site shows people get horrible palpitations, beats, breathlessness etc. I was diagnosed about 10 yrs ago but may have had AFib longer. I only discovered something was wrong at the gym when the heart monitors were showing a HR of 200 as I was warming up. Didn't feel anything just thought the machines were playing up, but after trying 3 machines all with same result I realised something must be happening. Anyway ended up going to A&E where HR was 140, but still no palpitations etc. So whenever I go into AF I just feel tired and cannot feel or count my pulse at my wrist cos its too fast, I tell my GP who organises an ECG which confirms it.
Hi Lily, I'm asymptomatic and my heart rate doesn't change when I'm in AF. Normally, it's 55-60 bpm and stays at that level. Since I have no symptoms, I don't know when I'm in AF. The only way to tell is with an EKG and that's how I was diagnosed. It was purely by chance that it was picked up. Hope that helps.
it’s definitely not a stupid question at all…many of us who are in persistent/permanent AF have a normal resting heart rate mine is 65-70 and have no awareness whatsoever of AF and our diagnosis was only discovered when attending hospital for other reasons..I count myself lucky to have been made aware of my AF and being on medication that will hopefully reduce the odds of a possible stroke.
I have been told I have afib, but I don't feel anything. I check my pulse with an oximeter several time a day and it's usually in the 50s and 60s. Sometimes in the 40s. Just sitting here, right now it's 58 with O2 at 97.
When I exercise (stationary bike and 13 lb. dumbbells') it gets into the 70s.
I think "asymptomatic" is when the atrium, during fibrillation, does not interfere too much with the rate of the ventricles so that even if the rhythm is irregular, the heart rate and output remain reasonably normal. I can't imagine a rate of, say, 150-180 ever being asymptomatic.
My elderly friend has asymptomatic AF and his rate stays within the normal range. He says that he's never aware of his AF except sometimes when walking up a slope or stairs. Lucky him!
Lily, I'm with you on that one!!! I feel mine and it's awful for around 30 hours! Having said that my brother had a stroke in January through undiagnosed afib he didn't know he had!
Very odd as I could always feel when my heart was going crazy - it would wake me up if it occurred during the night but if the heart rate is not very fast I guess you might not feel it. We had a visit from a sales person once and I let him have a go with my Kardia and it turned out he was in AF with a heart rate of 78 I think. He had driven some distance and drove off afterwards! His doctor had told him to take a daily Asprin. I take Flecainide regularly now so hardly ever have episodes but like all drugs it comes with side effects! Of course, we are all different so perhaps he really isn’t aware of it like the guy we met!
Firstly, all the best to you. I have virtually asymptomatic Afib...Sounds strange, but the time I notice anything is if I have had a drink of wine ( not all wine ), but again I now keep to the odd glass and then its minor. I do notice palpitations if I am on my left side in bed, but this is common with many Afib patients. I can go on my left side, but always after a time on my right!!
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