iRhythm Technologies, which specializes in digital cardiac care, presented encouraging results from a study on its Zio continuous ambulatory monitoring system that showed it is more efficient in detecting arrhythmias than competitors' monitors.

Holter monitors, created originally by Norman Holter, are a commonly-used, battery-operated portable device that records the heart’s activity.

The Holter and iRhythm’s Zio devices were tested on 116 patients who had recently experienced cryptogenic strokes or transient ischemic attacks, according to a May 18 press release. The findings were revealed May 18 at the European Stroke Organisation Conference in Prague.

"This research adds to the growing body of scientific evidence establishing that Zio by iRhythm is an efficient first line diagnostic tool for cryptogenic stroke and TIA populations, reliably detecting arrhythmias in a single monitoring period to accelerate care," said Judy Lenane, the executive vice president of operations and chief clinical officer of iRhythm, in a statement.

In the study, patients underwent ECG monitoring within three days of having a cardiac event and were randomly selected by a computer to either wear a Zio monitor for up to 14 days, or wear a Holter monitor for 24 hours. They were being monitored for paroxysmal atrial fibrillation (PAF).

Results showed that PAF was detected in about 16 percent of patients wearing a Zio monitor compared to only 2 percent of those wearing the Holter monitor. Based on this, the researchers said in the study it is likely a considerable proportion of PAF cases are missed by Holter monitors, which is the device currently used in the United Kingdom and in the U.S.

"We know with PAF, detection is key to preventing subsequent cryptogenic stroke or transient ischemic attacks,” said James T.H. Teo, MD, the lead author on the study and a consultant neurologist at Kings College Hospital in London, in a statement. “However, since PAF is temporary, many events fall outside the 24-hour monitoring period of Holters. Extended continuous cardiac monitoring is a superior solution after initial stroke or TIA as Zio by iRhythm extends the monitoring window to up to 14 days, detecting PAF events that may have otherwise gone unnoticed and allowing us to more promptly treat and protect these vulnerable patients."