iRhythm says Zio improved atrial fibrillation detection in study
iRhythm Technologies announced primary results of the mHealth Screening to Prevent Strokes study that evaluated detection of silent atrial fibrillation in high-risk individuals using Zio by iRhythm. Electrocardiogram recording and analysis were carried out using the FDA-cleared Zio by iRhythm ambulatory monitoring patch. After four months, the new incidence of AF was 5.1% among patients who were immediately monitored with the Zio Service compared with 0.6% in patients who were assigned to a delayed monitoring group and had not yet worn the Zio monitor. At one year, primary results showed that AF was newly diagnosed in 6.3% of patients who were actively monitored by the Zio service versus 2.3% in the observational control group receiving routine care. In addition, 4.0% of patients in the Zio monitored group were found to have potentially actionable arrhythmias other than AF including ventricular tachycardia, pause, AV block, and symptomatic supraventricular tachycardia. iRhythm added, "Monitoring with Zio led to significant change in clinical treatment of the actively monitored group including initiation of anticoagulation therapies (5.4%), antiarrhythmic medications (0.8%), and pacemaker placement (0.7%). Patients receiving anticoagulation for AF appeared to fulfill current clinical guidelines for appropriateness and need. Mean wear time for the Zio patch was 12 days with 98% analyzable ECG data." The study involved 5214 eligible Aetna members who were identified through claims data to have risk factors for AF but had not been previously diagnosed. 1738 individuals were enrolled via a web-based platform to undergo either immediate or delayed active ECG monitoring at home for up to 4 weeks with a Zio XT patch monitor. Each monitored participant was matched with two non-monitored participants with a similar CHA2DS2-VASc, a standardized stroke-risk assessment score, to act as controls. The study looked at time to first diagnosis of AF and its clinical consequences for the active monitoring cohort as well as the cohort undergoing usual care.