Adhesive Patch Detects More Arrhythmias Than Conventional Monitoring

An adhesive electrocardiographic (ECG) monitoring patch detected significantly more arrhythmias compared with the conventionally used Holter monitor, according to results from a recent study [Am J Med. 2014;127:95.e11-95.e17].

Ambulatory ECG monitoring is often used to detect asymptomatic cardiac arrhythmias in the outpatient setting. Introduced in the late 1940s, the Holter monitor remains the most commonly used method. In the past few years, however, development of the Zio^® Patch, an FDA-approved, single-lead, lightweight ECG adhesive patch monitor that can be worn for up to 14 days, has shown promise. Because the Zio^® Patch lacks external leads or wires and is water-resistant, patients may continue their normal activities of daily living with little disruption.

Between April 2012 and July 2012, Eric J. Topol, MD, Scripps Translational Science Institute and Scripps Health, and colleagues conducted a prospective analysis of 146 patients who were undergoing evaluation of cardiac arrhythmias and were referred for ambulatory ECG monitoring. The primary goal of the study was to compare the detection of arrhythmic events between the Zio^® Patch, used for up to 14 days, and standard 24-hour Holter monitoring. Secondary end points included the same comparison over a simultaneous initial 24-hour period and survey data that evaluated patient preferences regarding the devices.

Patients received both the patch and a Holter monitor; the devices were activated simultaneously. The patch features a trigger button, which,when activated, creates a digital time stamp, synchronizing the recorded ECG rhythm with symptoms. Patients were told to press the trigger if they experienced any symptoms of arrhythmia and to wear the patch as long as possible, for up to 14 days. Holter monitors were returned after 24 hours. The median wear time for the devices was 1 day for the Holter monitor and 11.1 days for the patch.

There were 6 types of arrhythmias recorded, which also included supraventricular tachycardia: atrial fibrillation/flutter, ventricular tachycardia, or polymorphic ventricular tachycardia/ventricular fibrillation. Arrhythmias were then categorized into 2 groups, with the first consisting of all 6 arrhythmias, and the second including only the 5 most clinically significant (excluding supraventricular tachycardia).

Results from the analysis of overall wear time showed the patch detected significantly more of the arrhythmias than the Holter monitor: 96 events versus 61, respectively (P<.001). Sixty events were detected by both devices. The patch detected 36 events that were not detected by the Holter monitor, while the Holter monitor detected 1 event that the patch did not detect.

When the researchers excluded less clinically meaningful supraventricular tachycardia from the total wear time analysis, the number of arrhythmic events decreased but the adhesive patch still detected significantly more events than the Holter monitor (41 versus 27, respectively; P<.001). Twenty-seven events were detected by both devices. The researchers also noted that 14 clinically significant arrhythmias were detected by the patch, but not by the Holter monitor.

When comparing results from the initial 24-hour monitoring period, results showed the Holter monitor detected significantly more arrhythmias than the patch: 61 events compared with 52, respectively (P=.013). Fifty of these events were detected by both devices. Of the 11 events not detected by the patch in the first 24 hours, 10 were subsequently detected with extended monitoring.

Finally, survey results showed that 93.7% of patients found the patch to be more comfortable to wear compared with 51.7% for the Holter monitor. When asked if the device affected the performance of their daily activities, 10.5% of patients who wore the patch indicated that performance was affected compared with 76.2% of patients who wore the Holter monitor. The majority of patients surveyed (81%) responded that they would prefer to wear the patch instead of the Holter monitor. Most physicians (90%) thought a definitive diagnosis was obtained using data from the patch as opposed to 64% using data from the Holter monitor.

“The Holter monitor has been extremely important for tracking and diagnosis of heart rhythm disorders,” Dr. Topol said in an interview with First Report Managed Care. “But our study shows the efficacy of a new, simple, alternative patch that can obtain considerably more information, while at the same time being far more convenient and palatable for the patient.”