Anyone who has been suspected of having a heart arrhythmia is likely familiar with a Holter monitor. This is sort of a portable ECG that records your heart waves over a period of time. You wear it as you go about your normal daily activities, in hopes that it will catch and record an episode when your heart is out of rhythm. These devices typically record two days’ worth of data, at which point the patient returns to the doctor’s office to return the device so that the results can be analyzed.

Results from a new study raise doubts about whether the traditional Holter monitors are sufficient for the task. The study was presented at a meeting of the American Heart Association (AHA), and explores the benefits of monitoring patients over a longer period of time. The study examined the results from nearly 400 patients who wore a Zio heart monitor from iRhythm Technologies. This is a smart patch that patients wear on their chests for up to two weeks.

The study found that more than half of the patients in the study had a significant arrhythmia. However, more than half of those did not show any irregular heartbeats within the first 48 hours. This means that they likely would not be diagnosed correctly based on data from a Holter monitor. The extended monitoring period resulted in more accurate diagnosis, aided by iRhythm’s Cloud-based analytics. The wireless Zio device is much less intrusive than a typical Holter monitor, making it more convenient for patients.

This is a clear example of how sophisticated wearable technology can result in better outcomes for patients, and by avoiding false negative results, could conceivably avoid more expensive treatment that could come from missing an arrhythmia. The study points the way toward future research into the use of wearable Health Tech devices to improve patient monitoring.