SAN DIEGO — A small adhesive wireless monitor worn on the chest for up to 2 weeks detected cardiac arrhythmias in patients with stroke or transient ischemic attack, according to findings presented at the International Stroke Conference.
Because many arrhythmias detected by the FDA-cleared, single-lead monitor (Zio Patch, iRhythm Technologies Inc.) occurred more than 48 hours after the start of monitoring, the device may be superior to the Holter monitor, which monitors for only 24 to 48 hours, researchers said.
“Extended cardiac monitoring for 14 days with the Zio Patch device detects atrial fibrillation in about one of 20 patients with stroke or TIA,” Maarten G. Lansberg, MD, PhD, assistant professor of neurology and neurology sciences at Stanford University Medical Center, told Cardiology Today. “A traditional workup for AF with ECG and/or 24-hour Holter monitoring would have frequently missed the diagnosis of AF in these patients because the AF is intermittent and often does not manifest itself until more than 48 hours after the start of monitoring.”
Maarten G. Lansberg
Lansberg and colleagues analyzed monitoring reports of 1,171 patients (mean age, 67.9 years; 55% men) collected from iRhythm Technologies. The median monitor wear time was 13 days (interquartile range, 7.2-14) and the median analyzable time relative to total wear time was 98.7% (interquartile range, 96-99.5).
The researchers found that AF was present in 4.8% of all reports (paroxysmal AF, 4.2%; chronic AF, 0.6%), and 14.3% of the first paroxysmal AF episodes occurred 48 hours after the start of monitoring. The mean duration before the first episode of paroxysmal AF was 1.5 days and the median duration was 0.4 days. Mean paroxysmal AF burden comprised 12.7% of the total monitoring duration.
Surpaventricular tachycardia was detected in 51% of cases.
Detection of AF in a patient with stroke or TIA often changes the antithrombotic regimen from antiplatelet therapy to anticoagulation therapy, Lansberg and colleagues noted.
The wireless monitor appears to be “a practical solution for the diagnosis of AF that patients who have suffered a stroke or TIA can easily comply with,” Lansberg said in an interview. “There are multiple monitors on the market that can be used for the detection of AF after stroke and TIA. The findings of this study suggest that the Zio Patch may be a very effective monitor for this specific purpose that is well-tolerated in the stroke population.”
The next step, he said, is a prospective study comparing the Zio Patch head-to-head with standard Holter monitoring in this patient population. Such a trial is currently being designed. – by Erik Swain
For more information:
Tung CE. Abstract WMP63. Presented at: International Stroke Conference 2014; Feb. 12-14, 2014; San Diego.
Disclosure: The data for the study were provided by iRhythm Technologies. Lansberg reports no relevant financial disclosures.