Some smartwatches and wearable patches are now as accurate as medical-grade electrocardiograms (ecgs) in detecting common heart rhythm problems more than 90 percent of the time, offering a perhaps life-saving glimpse into your cardiovascular health.
Wearable Tech and Your Heart: What’s Reliable?
Table of Contents
Wearable devices are evolving, but not all heart-health tracking features are created equal.
- Wearable devices can detect irregular heart rhythms with increasing accuracy, especially those using ECG sensors.
- Activity tracking through wearables can motivate increased exercise,a cornerstone of heart disease prevention.
- While helpful, wearable sleep data shouldn’t replace a professional polysomnography (sleep study) if you suspect a sleep disorder.
- Blood pressure readings from wearables are frequently enough less reliable than customary cuff measurements.
- Heart rate variability (HRV) is a complex metric and shouldn’t be a source of undue worry.
Detecting Heart-Rhythm Issues
One of the most promising capabilities of wearable technology is its ability to identify irregularities in your pulse. These devices typically rely on a combination of sensors to monitor heart rhythms:
- Accelerometer sensors, which detect motion and acceleration
- Electrocardiograph (ECG) sensors, which record the heart’s electrical activity
- Photoplethysmograph (PPG) sensors, which use infrared light to measure blood flow
These sensors can detect atrial fibrillation (AFib), a common type of irregular heartbeat that increases the risk of stroke.If a wearable detects AFib, it can prompt you to consult a doctor for further evaluation.
Boosting Activity Levels
Beyond detecting heart problems, wearables can also encourage healthier habits. Studies have shown that individuals who use activity trackers tend to take more daily steps and dedicate more time to exercise than those who don’t.
Understanding Sleep Patterns
Numerous rings, bands, and similar devices track sleep duration and quality, typically using PPG sensors and accelerometers to monitor changes in heart rate, body temperature, and movement during sleep. While this information can help identify potential sleep disorders, wearable devices are not a replacement for polysomnography, a complete laboratory sleep study. If your device suggests sleep issues, discuss next steps with your doctor to determine if a diagnosis is warranted.
Monitoring Oxygen Levels
Wearables can also measure blood oxygen saturation, known as pulse oximetry.Low blood oxygen levels can be indicative of heart disease and other conditions.Dr. Akoum notes that this feature can also be helpful in detecting symptoms of obstructive sleep apnea. Untreated sleep apnea can elevate the risk of irregular heartbeats or high blood pressure, potentially leading to heart failure or stroke.
Detecting Variations in Heart Rate and Stress
Devices commonly use ECG or PPG to track heart rate variability (HRV), the time interval between heartbeats. A higher HRV is generally considered favorable, while a lower HRV may suggest stress, fatigue, or a heart issue. However, interpreting HRV is complex.
“I wouldn’t say heart rate variability is something that people should fixate on, which a lot of people tend to do, because a lot of things influence it,” says Paul Leis, DO, a cardiologist and an assistant professor of medicine at the Icahn School of Medicine at Mount Sinai in New York. “Even a simple illness can change heart rate variability readings, and that can spiral into unnecessary worry.”
Reading Blood Pressure
Some manufacturers claim their devices, such as watches, can track blood pressure, but these measurements aren’t always reliable. Traditional blood-pressure monitors use an inflatable cuff around the arm to measure arterial pressure.While some wearables include a wrist-worn cuff designed for periodic inflation, this method is generally considered less accurate than upper-arm measurements. Smartwatches that estimate blood pressure using PPG sensors also don’t match the accuracy of traditional cuffs.
