An electrocardiogram (ECG) is a test used to check the heart's rhythm and electrical activity. ECG machines found in clinics and hospitals typically have about 10 to 12 leads-sensors that attach to the skin. These sensors allow the machine to accurately record the electrical signals produced by the heart.
There are also various wearable ECG devices that come in different forms and can track heart activity on the go. This makes them ideal for users who want to monitor their heart health without disrupting their daily routines.
Beyond being more convenient, these devices can also detect trends that a one-time ECG test might miss. However, because of their portability, they usually have only 1 or 2 leads, which may not be as accurate as a hospital-grade ECG.
In this article, we'll explore the different types of wearable ECG devices, their pros and cons, important factors to consider when purchasing one, and tips for getting more accurate readings.
Types of Consumer Wearable ECG Devices
There are a few main types of consumer wearable ECG devices in the market. Each of them work similarly to allow users to check their heart rhythm while on the go.
Smartwatches and fitness trackers
- What are they?
Smartwatches and fitness trackers may come with an ECG function that can track the user's heart rate. This can detect signs of arrhythmia (irregular heart rhythm) which is a cause of stroke.
- How do they work?
An ECG can be taken with a smartwatch if there is a complete electrical circuit around the user's body. While wearing the watch, the user has to launch the phone app and place a finger on a specific part of the watch to complete the circuit.
Within a few minutes, the watch will be able to measure the user's heart activity and deduce if it is normal.
ECG patches
- What are they?
ECG patches are small, extremely portable devices that are attached to the body. They are used to receive and transmit electrical signals of the user's heart activity.
- How do they work?
A wearable ECG patch is equipped with an electrocardiography sensor and accelerometer to detect and record physiological data. Similar to smartwatches, ECG patches can be synced with a device such as a phone or tablet to display the results.
Chest straps
- What are they?
A chest strap ECG has a portable sensor attached to a strap. This can be worn under the user's shirt to track the heart rate even while exercising.
- How do they work?
Electrode sensors are usually embedded in the chest strap such as when a user wears it, it can detect the heart's electrical activity. The strap may be made of fabric, plastic or rubber.
The data collected can also be synced to a device like a phone or tablet.
Clothing and shoe-embedded sensors
- What are they?
These refer to clothing or shoes that have been embedded with sensors to track the user's heart activity. The sensors can come in the form of a strap or patches embedded within the clothing.
- How do they work?
The fabric electrodes included in clothing and shoes act as sensors to record electrical signals from the heart. Results can be easily monitored via a synced device.
These apparel can be easily incorporated in a user's daily activities since it does not require any additional wearables.
Pros of Wearable ECG Devices
Lightweight and portable
As compared to ECG machines, wearable devices are lightweight and portable. This means that patients need not schedule an appointment with their doctor in order to get a quick analysis of their heart activity. It can be done almost anywhere and any time with wearables.
Able to identify potential problems early
Taking an ECG test at the clinic may not provide a full picture of a patient's health condition. Having a wearable device allows one to record heart activity more conveniently and for a longer period of time. This enables doctors to identify any trends that may indicate problems. Early detection is also made possible.
Shareability of data
On top of being able to track heart activity anytime, patients can also sync the collected data with their doctor. From there, they can track their heart health easily together with their caregivers.
In Asia Pacific, companies have begun to digitize healthcare in the area of telemedicine. Elisabeth Staudinger from Siemens Healthineers shares that digital healthcare is benefitting over one billion people in the region today. The shareability of data from wearable ECGs can contribute to achieving an improved, 24/7 healthcare system.
Cons of Wearable ECG Devices
Limited data
Wearables can only provide basic information on the go, such as heart rhythm and rate. Some may also be able to measure blood pressure.
While wearable ECGs may detect heart rhythm abnormalities, they cannot detect other cardiovascular conditions such as heart attack, high cholesterol and stroke. This limited data only serves as a gauge of the patient's overall heart health as it does not provide the full picture.
For a comprehensive analysis, patients will need to head to a clinic with a hospital-grade ECG machine.
May not be accurate
Wearable ECG devices typically come with 1 or 2 leads (contact points on the body). On the other hand, hospital-grade ECGs have 12 leads which makes them more sensitive.
This means that wearables can pick up electrical signals from the heart, but not as accurately as a hospital-grade ECG.
Furthermore, the accuracy of wearables can also be affected if the user does not use it as instructed or has sweat or moisture on their skin where it comes into contact with the device.