Dr. John Day, Cardiologist

How Do You Know If You Are in Atrial Fibrillation?

Sometimes it is hard to know what your heart is doing.  Fortunately, with a few simple tricks, you can tell with 99% accuracy if your heart is out of rhythm.  In this article, I’ll teach you how to know if you are in atrial fibrillation.

Kim’s Experience

Kim was never quite sure when she was in atrial fibrillation.  She didn’t get the palpitations that her sister and neighbor got when they had an atrial fibrillation attack.

All she knew was that sometimes she just felt tired.  That was it.  No palpitations, no shortness of breath, no chest pain, and no dizziness.  Just fatigue.

“How come I can’t feel my atrial fibrillation,” Kim asked.

“Many people can’t feel their hearts beating irregularly,” I said.

“Then how do you know if you are in atrial fibrillation?” she asked.

“Check your pulse,” I said.

“I think I can feel my pulse,” she said.

“Good.  If your pulse is regular and is beating about once a second, then you are likely in sinus rhythm.  If the pulse is irregular and fast then you are probably in atrial fibrillation,” I said.

How do you know if it is atrial fibrillation or just your heart skipping beats? She asked.

“If it is an occasional missed beat, and all the other beats are perfectly timed, then it is probably just a premature beat,” I said.

How Do You Check Your Pulse?

Checking your pulse to see if you are in atrial fibrillation is simple.  Indeed, most of my patients can learn to tell within 10 seconds.  All you have to do is find your pulse.

How you check your pulse doesn’t matter.  It can be on your wrist, neck, the temple of your head, or just about anywhere else you can feel your pulse.

If you feel your pulse about once per second, and it is regular, then you are probably in sinus rhythm. Atrial fibrillation typically has a fast and chaotic pulse.  The heart rate is often faster than 100 beats per minute at rest, and every heartbeat is irregular.

What Should Your Heart Rate Be?

Most people have a resting heart rate of 50 to 90 beats per minute.  If your heart goes into atrial fibrillation, it will likely be at least 10 to 20 beats per minute faster.

Of course, there are no hard and fast rules.  Sometimes the heart rate slows with atrial fibrillation.  It is for this reason that you can’t rely on the heart rate alone to tell if you are in atrial fibrillation.  You also have to check your pulse to know if the heartbeat is regular or not.

If you want to learn more about what your heart rate should be, here is an excellent article I have written on this topic:

What Should Your Resting Heart Rate Be?

How Often Should You Check Your Pulse

For my patients with atrial fibrillation, I recommend that they check their pulse twice daily.  The reason for a twice daily check is to minimize their risk of stroke.  Knowing your rhythm is especially important for those people not taking a blood thinner.

The reason for the twice-daily check is because studies show that the risk of a stroke starts going up somewhere around 24 hours of uninterrupted atrial fibrillation.  If you are checking your pulse twice daily, then you will be able to detect atrial fibrillation before this 24 hour time point.

What Should You Do if You Can’t Feel Your Pulse?

As many of my older patients struggle to feel their pulse, there are other ways to tell if you are in atrial fibrillation.  Here are some different ways to check your pulse if you can’t feel it on your wrist or neck.

1.  Have Your Spouse Put Their Ear to Your Chest

If your spouse puts their ear on your chest, it is almost like using a stethoscope.  When your heart is in rhythm, they should hear a regular heartbeat at about once per second.  If, however, you are in atrial fibrillation then they should hear faster and irregular heartbeats.

2. Buy a Stethoscope

Stethoscopes are cheap.  For example, Amazon’s choice for stethoscopes will only set you back $25.48 at the time of this writing.  As with #1 above, if you are in atrial fibrillation the “lub dubs” should be fast and irregular.

3. Buy a Blood Pressure Monitor that Detects an Irregular Pulse

Every home needs a blood pressure monitor.  As high blood pressure is one of the leading causes of heart disease, knowing your numbers could save your life.

When shopping for a blood pressure monitor, look for one that will also detect an irregular pulse.  Usually, these monitors will have a heart icon on the screen.  Whether or not the heart icon is lit up or not will tell you if your pulse is regular or irregular.  The only challenge with these devices is that the blood pressure machine can’t know the difference between atrial fibrillation and skipped heartbeats.

4. Buy a Pulse Oximeter

Pulse oximeters are also cheap.  The best selling model on Amazon was only $18.95 on my last check.  While most people buy a pulse oximeter to see what their oxygen saturation is, it can also be used to monitor for atrial fibrillation.

As with a blood pressure machine, you can’t just focus in on the actual pulse number.  You need to carefully look at the flashing or blinking lights on the pulse oximeter.  Every time the pulse oximeter detects a heartbeat, it will flash or blink.  If you are in atrial fibrillation, the flashing or blinking will be fast and irregular.

5. Turn Your Smartphone into an EKG Machine

For $99 you can turn your smartphone into an EKG machine with the Alivecor system.  Hundreds of my patients have used this device with excellent results.

With the Alivecor system, you put your thumbs on the small Bluetooth electrodes.  The electrodes then transmit the data to your phone.  With the app, you can see your actual EKG.  While the app can give you a reasonably accurate EKG interpretation, you’ll want to show it to your doctor for confirmation.

Practical Tips

It really doesn’t matter how you check your pulse.  The key is to be consistent.  With a little training, most of my patients can tell if they are in atrial fibrillation with 99% accuracy.