Generally speaking there are two forms of Atrial Fibrillation, paroxysmal and persistent. Paroxysmal is intermittent; persistent is constant. (I have persistent AF.)
Because paroxysmal AF does not happen all the time, it makes sense to take heart rate measurements manually or (as imperfect as these machines may be) using a cuff, pulse oximeter or other monitoring equipment that provides single-digit (or in some cases single-response) answers indicating either that one’s heart rate is a certain number of beats per minute (bpm) or that one’s heart is in atrial fibrillation. I imagine a reason a paroxysmal AF person might taking a heart rate knowing it might return the answer “in afib” might be to notice what is happening at the time and try to change one’s behavior to ensure more afib occurrences don’t happen as often.
Because persistent afib is happening all the time, it makes no sense to manually check one’s pulse or use a machine like a cuff or pulse oximeter (except to check blood pressure and blood oxidation levels respectively). Single digit answers (bpm = x) are, by (the) definition (of arrhythmia) simply irrelevant to AF.
However, for people in Persistent AF, a trend plot allows you to understand when your heart is running faster or slower than you’d like. Why might you want to know if your heart is running too fast or too slow?
a)To change your lifestyle so that you can better control your heart.
b)To independently check if the drugs you are taking or your pacemaker is successfully controlling your heart rate swings. (In my case, drugs control the highs and a pacemaker controls the lower limit.
THE FITBIT provides heart rate trends. (It is the only affordable commercial device I know that does this. The AliveCor Kardia unit also provides a heart rate trend but, because it can at most only track five minutes of activity and during that time effectively ‘handcuffs’ your hands. (More about this unit in Part 5 please.)
Fitbit trends include:
a)BPM RESTING RATE: A for-the-day heart rate trend accessed you click on the bpm (heart) icon.
b)WORKOUT: A more specific heart rate trend relating to time you specify to be a “workout”. (This is very useful because you can specify certain heart rate ranges to be “custom” and get a report indicating the amount of time your heart operated in your custom range.)
Fitbit problems include:
a)The Fitbit is certainly not the final word on heart rate measurement. Many (my cardiologist included) contend that Fitbit heart rate measurements are not accurate.
b)WORKOUT: The Fitbit does not always respect time you specify to be a “workout”. It assumes any workout will involve a heart rate increase. If it thinks your “workout” heart rate is too slow, it will automatically consider it to be sleep time. There are work arounds to get around this erroneous and annoying behavior.
I can go further, but would like to hear your comments regarding the Fitbit and its use within an afib environment. Most specifically I’m interested in how you feel about the fitbit’s heart rate accuracy. (I personally believe that, because it is recording a trend that even if it only gets it right one heartbeat out of ten it still provides a fairly accurate heart rate trend measurement.)