Holter Monitor vs. Wearable Device

cardiogram Wearables

Both Holter monitors and wearable devices have been found beneficial in detecting arrhythmias and heart rate abnormalities. But which device would be most beneficial overall? First, let’s look at the differences between the two:

Holter Monitors

Holter monitors are compact, portable devices that take a continuous recording of your heart’s rhythm.(5) They are equipped with electrode stickers that stick to your chest and are attached to lead wires that plug into the device. The device is worn anywhere from 24-48 hours (sometimes longer, depending on the frequency of symptoms). While the Holter monitor is worn, it captures every heartbeat the patient has, essentially giving you a 24/48-hour recording of your heart’s rhythm.

Wearing a Holter monitor is like being hooked up to a continuous ECG monitor. (Normally, ECGs only record a 10-second strip.) Wearing a Holter monitor is beneficial if you think you have a heart rhythm abnormality that can’t be caught on a wearable. Sometimes, arrhythmias are asymptomatic, so a Holter monitor would be beneficial in catching an abnormal rhythm you are not aware of. It is also easier to catch arrhythmias that are few and far between on a Holter monitor because of its precise and continuous recording. If your physician suspects that you have an arrhythmia due to symptoms such as unexplained fainting, or if you have a heart condition that increases your chance of having an arrhythmia, you would likely benefit from wearing a Holter monitor.

Pros: Offer precise heart rate monitoring, great for clinical use to detect heart rhythm conditions

Cons: Uncomfortable, less convenient, must be accessed through a physician

Wearables (better known as smartwatches) are devices worn around the wrist that are like tiny computers. Wearables have many features, like being able to make phone calls, send texts, and check the weather. Although wearables have many features, in this article, we’ll focus on those that are health-related. Wearables offer many benefits for tracking your health, including step counting, heart rate monitoring, measuring body temperature, and ECG recording. Let’s take a more in-depth look at some of these features:

Heart rate monitoring

Almost all wearables are now equipped with heart rate tracking. They show your resting, average, and peak heart rates throughout the day. Keeping track of heart rates is important for people who have certain medical conditions or who are trying to get diagnosed with those conditions. It is also important for people who are checking to see if their medications or a new health or fitness routine is working. Certain apps such as Cardiogram will give you a detailed heart rate graph that you can use to track your heart rate and bring to your physician.
Blood pressure monitoring

Certain smartwatches are now equipped with blood pressure monitoring, like the Samsung Galaxy Watch 4.2 This is beneficial to someone who needs to keep track of their blood pressure for reasons such as testing the efficacy of a medication, or for someone who suspects they have hypertension.

SpO2 (blood oxygen level) monitoring
Blood oxygen level monitoring is important for many reasons. Once in the bloodstream, oxygen offers many benefits such as replacing worn-out cells, providing energy, and supporting our immune system. Having low blood oxygen levels can mean there is an issue with your circulation or lungs. A normal blood oxygen level reading is between 95%-100%, with exceptions for certain medical conditions such as COPD.3
Step counting
Monitoring your steps during the day gives you a good idea of your overall activity levels. Although we have all heard that 10,000 steps a day is the gold standard, benefits plateau around 5,000 steps a day.4
ECG recording
Some wearable devices, such as the Apple Watch and Fitbit, have built-in ECG recording capabilities. This is not a continuous recording, but rather a quick, 30-second single-lead ECG. This is beneficial if you are having symptoms, so you can take a recording at that moment to show your doctor. They can then check to see if there was anything off with your heart’s rhythm.

Pros: Easily accessible, comfortable wearability, cost-effective, offer powerful heart rate self-monitoring with the option to share with a doctor.

Cons: Not able to use for a full diagnosis.

Wearable or Holter Monitor: Which Should I Choose?

While Holter monitors are highly accurate and physicians rely on them for diagnosis, there are drawbacks. Holter monitors can only be worn for a certain amount of time (normally 24-48 hours), unlike wearable devices which can be worn daily. They can also be very costly, ranging from $300 USD-$2,200USD per test, even with insurance coverage.6 The device may also need to be worn multiple times to catch an arrhythmia, causing the bill to add up that much more. The monitors can also be uncomfortable, with many patients complaining about skin irritation due to the adhesive on the electrodes. The monitor and wires can also be cumbersome, possibly getting in the way of daily activities.

On the other hand, wearables are convenient, cost-effective, and accurate. This journal7 outlines 18 studies conducted to detect atrial fibrillation, bradyarrhythmias, tachyarrhythmias, and premature contractions in 424,371 subjects using smartwatches with photoplethysmography (PPG) technology. Smartwatches were able to correctly identify arrhythmias 85% of the time, and identify patients without an arrhythmia 100% of the time.7

Another study had participants wear a Holter monitor and Garmin smartwatch simultaneously for 24 hours to screen for atrial fibrillation. Overall, smartwatches were able to detect atrial fibrillation with 89.7% accuracy.8  Atrial fibrillation (AF) beats on the wearable PPG device were determined to be AF or non-AF beats using a certain formula. Then, these labeled beats were compared to the simultaneously-worn Holter ECG for accuracy.

 Additionally, smartwatches with PPG technology can cost anywhere from $40USD-$1,700USD, a drastically favorable price difference compared to a Holter monitor. Wearables generally only have to be purchased once and can last for several years, if not longer with proper care.

Wearables: A Great Choice for Continuous Monitoring
While physicians can rely on Holter monitors for a diagnosis, they may not always be the best option for every patient. They are costly, uncomfortable, and can only record for a short amount of time. On the other hand, wearables are convenient, comfortable, and cost-effective, offering continuous daily monitoring and reliable accuracy. And with apps like Cardiogram, they also have the power to offer minute-to-minute heart rate monitoring and the ability to easily share that data with your doctor, which can help to detect heart rhythm conditions and get you a diagnosis that much sooner.


Cardiogram app shown on phone and smart watch


Cardiogram app shown on phone and smart watch