Five years after his “widow maker” heart attack, my husband John experienced several irregular heartbeat (AFib) episodes. Two weeks ago, he underwent quadruple bypass surgery. We need to monitor he heart rate as well as the rhythm.

The Apple Watch Heart Rate App can monitor the bypass patient’s heart rate and heart rhythm in real-time continuous mode. While it’s actually simple to set up, Apple throws silly vocabulary at us that needlessly confuses things. Learn how to set up the Apple Watch with ease so that you can monitor and record the bypass patient’s heart rate and rhythm.

We use our Wellue monitor at home, but we want a watch monitor for therapy walks. Here is everything I learned about using the Apple watch to monitor heart rate and heart rhythm. While I wrote this for the bypass patient doing daily walks, it’s just as relevant to monitoring the resting heart as well. My husband has clogged arteries and AFib, and we will use the Apple Watch to monitor both.

You Need Both the Watch AND the iPhone to Proceed

Setup of the Apple Watch depends on a paired iPhone. Even if you are not hooking up cell phone functions to your new watch, you still need the iPhone for watch configuration. The iPhone can display more information on its screen than the watch can display on the watch screen.

There are two ways to do continuous heart rate monitoring with the Apple Watch. The “Docking” method described below depends on your having an iPhone to put the Heart Rate App in the Apple Watch “Dock.”

These Apple Watch Models Have Heart Rate Features

All Apple Watches starting with Series 1 have the Heart Rate notifications and resting measurement ability. Your watch must be new enough to accept Apple WatchOS 5.1.2 or greater to have the irregular heartbeat monitor. The irregular heart rate functionality is not available in all areas of the world. See Apple’s explanation here where it says “Irregular Rhythm Notification.”

How to Get the Apple Watch Heart Rate Monitor and App

The watch contains both the physical sensors and the software right off the shelf. You don’t need to buy anything extra to get the functionality. So long as you have the minimum hardware and software requirements mentioned in the previous section of this article, you’re good to go.

Background, Ad Hoc, Docked and Fitness App Measuring Modes

The Apple Watch has four times or modes when it scans the wearer’s heart information. The background and ad hoc measurements take discrete recordings and then stop measuring. The Fitness and Dock modes continuously scan and record until you stop the measurements.

The Apple Watch automatically checks heart functions in the background. This enables it to calculate resting heart rate and calories expended without opening the Fitness App.

It measures at various times throughout the day, and these times change based on the wearer’s energy expenditure. It does fewer measurements when the wearer is resting and more when the wearer is moving.

Swipe to the Heart Rate App to trigger an on-demand scan. Opening the app starts the reading. Wait several seconds to see the results. I call this the Ad Hoc mode.

To get continuous readings, use the Fitness App or Dock modes. To access these modes, you will need to add the Heart Rate App to the Fitness Face or to the Dock, respectively. I explain how to do these tasks below.

Access Background Heart Monitoring

You can run the Heart Rate Monitor in the background. The watch will measure on its own schedule, rather than one you define. This mode calculates resting heart rate and monitors for irregular heart rhythm. If you are having an Afib event during a measurement cycle, the watch will display an alarm. Learn more about background monitoring on Apple’s site.

Use the Heart Rate App for Ad Hoc Testing

If you want to force a measurement, open the Heart Rate App. Just opening the app starts a measurement cycle. The watch lights the vessels under the sensor to calculate heart rate and rhythm. You wait just several seconds to get an up-to-date readout.

Add the Heart Rate App to the Fitness Face for Continuous Monitoring

A watch “complicattion” is any function the watch does besides telling the time.  Watch people (horologists) know that, but I had to look it up. Up front, I had found the idea of “Adding the Heart Rate App as a complication to the Fitness App” to be a nonsensical statement.

That’s where I was when I began this journey. Now that I understand how continuous monitoring works, I will answer this for you as well.

So here’s what’s going on.

This app is a “complication” because it does something other than measure time. The Heart Rate App measures your heart’s rate and rhythm.

The Fitness App is also a “complication.” Rather than tell the time, it tracks your activities such as walking and running.

Everything besides MINUTES and SECONDS is a “complication.” When you see the word “complication,” you can substitute “app,” “program” or “function” to translate Apple to Human.

The Apple Watch “face” is the display. You can use the word’s “face” and “display” interchangeably.

You have the choice of displaying an app’s data on the watch face or allowing the app to run out of sight. When you assign the app to the watch’s display, Apple calls this “setting the face.”

For example, when you run the Fitness App AND set the Fitness App to display on the screen, you are using the Fitness Face.

Now that we have the vocabulary, it’s actually very easy to explain how to add continuous monitoring through the Fitness App.

To use the Fitness App to display continuous heart rate monitoring, you will:

1. Star the Fitness App
2. Set the watch to display the Fitness App
3. Add the Heart Rate App to the watch display

In Apple Speak, you are

4. Starting the Fitness App
5. Setting the Display to the Fitness Face
6. Adding the Heart Rate App complication to the Fitness Face

You can actually add the Heart Rate App to any “face” that accepts “complications.” It just makes the most sense to add the Heart Rate info to the Fitness info.

Although I think they’re worse than useless, you might have more luck with the Apple instructions for changing the watch face. I had much better luck understanding PC Magazine’s explanation.

Add the Heart Rate App to the Dock for Continuous Monitoring

The second mode continuous monitoring is to add the Heart Rate App (complication) to the Apple Watch Dock. The Dock is a shortcut screen you access either swiping up from the bottom or by turning the digital crown. It displays up to ten app shortcut screens. You must have the iPhone to set up your Dock shortcuts. You will use the Apple Watch App on the iPhone to add the Heart Rate App to the Watch Dock.

See Apple’s Dock info here.

Measuring Cool Down Heart Activity on the Apple Watch

John’s surgeon instructed him to measure his heart rate:

1. resting before the walk
2. while walking
3. at the end of the walk

The surgeon did not ask for measurements once John rested after the walk. However, I’m very interested in this number. John’s heart rate is very high, and I’d like to know that it’s going toward normal after exercise.

We take the third measurement as we are finishing the walk. To get a resting heart rate after the walk, we turn off the app. The Watch continues to record for three more minutes. We can then go back to that three-minute period to see how far the rate dropped once resting, and how long it took to get there.

The Heart Rate BPM Alarm Works with One Flaw

The bypass therapy instructions say to force a rest if the heart rate rises more than 20 BPM during the walk. So we have a variable heart rate range every day. Whatever the resting starting rate is, the range is that number to that number plus 20 BPM.

On Day 14, our walking target is 16 minutes. John started at 83 BPM, so our target range was 83 BPM to 103 BPM. We set the alarm range of 83 BPM on the low end, and 103 BPM on the high end. This works great for ten minutes, and then we run into the logic flaw.

Apple says that its watch stops measuring for alarm BPM after 10 minutes. If the BPM range has not violated the lower or upper targets, the watch goes into “inactivity” mode.

This is despite the fact that John’s heart rate during those ten minutes ranges from 83 BPM to 102 BPM. It didn’t set off an alarm, but it’s hardly the BPM you see during inactivity. To use the BPM alarm for the entire walk, we need to reset the alarm at the ten-minute mark.

If your heart rate remains above or below a chosen beats per minute (BPM) while you appear to have been inactive for a period of 10 minutes, your Apple Watch can notify you. (Apple)

Graphing the Heart Rate Changes As We Walk

We will use the Fitness App “Outdoor Walk” activity to record John’s progress.

The Fitness App adds the ability to graph the heart rate changes as we walk. This allows us to analyze when the heart rate steadied and when it spiked. The watch keeps an historical record of each walk.

We can compare today’s heart rate at the 10-minute mark to last week’s heart rate at the same 10-minute mark. We can also analyze present data to see where John might be over exerting himself. If his heart rate goes 20 BPM over the resting rate, we can pinpoint at what minute mark in the walk this happened. The next day, we can check if things are dangerous or getting better at that minute mark.