A real-world study found that the Reveal LINQ insertable cardiac monitor had an atrial fibrillation detection rate of 16.3 percent, which was a 32 percent relative increase compared with the rate found in a previous randomized, controlled clinical trial.

Medtronic, which manufactures the Reveal LINQ, announced the results on April 20. The findings were presented at the American Academy of Neurology’s annual meeting in Vancouver, Canada.

The Reveal LINQ received 510(k) clearance from the FDA in 2014. That same year, the CRYSTAL AF study found that atrial fibrillation was detected in 12.4 percent of patients who received the Reveal LINQ at one year compared with 2.0 percent of patients in the control group.

The CRYSTAL AF study included patients who were at least 40 years old, had received a diagnosis of stroke or transient ischemic attack within the previous 90 days and had no evidence of atrial fibrillation during at least 24 hours of ECG monitoring. The results of the randomized study were published in the New England Journal of Medicine on June 26, 2014.

In the real-world study, Medtronic evaluated 1,247 U.S. patients who had cryptogenic strokes and received a Reveal LINQ. After a year, the Reveal LINQ had detected 1,737 atrial fibrillation episodes in 192 patients.

Medtronic said that 72 percent of patients diagnosed with atrial fibrillation in the real-world study would have been undiagnosed if the cardiac monitoring was limited to 30 days. Current guidelines recommend monitoring atrial fibrillation for 30 days within six months of patients having a cryptogenic stroke.

The Reveal LINQ, which is one-third the size of a AAA battery, is inserted in the upper left side of the chest and communicates with a patient bedside monitor that uploads data to Medtronic’s CareLink network. The system detects and records abnormal heart rhythms for up to three years, according to Medtronic.