Comparing 14-day adhesive patch with 24-h Holter monitoring

The investigation of cardiac arrhythmias in the outpatient ambulatory setting has traditionally been initiated with the Holter monitor. Using the continuous recording over 24 or 48 h, the Holter monitor permits the detection of baseline rhythm, dysrhythmia and conduction abnormalities, including heart block and changes in the ST segment that may indicate myocardial ischemia. However, apart from the bulkiness and inconvenience of the device itself, the lack of extended monitoring results in a diagnostic yield of typically less than 20%. In this study by Barrett et al., 146 patients referred for the evaluation of cardiac arrhythmia were prospectively enrolled to wear both the 24-h Holter monitor and 14-day adhesive patch monitor (Zio (R) Patch) simultaneously. The primary outcome was the detection of any one of six arrhythmias: supraventricular tachycardia, atrial fibrillation/flutter, pause >3 s, atrioventricular block, ventricular tachycardia, or polymorphic ventricular tachycardia/fibrillation. The adhesive patch monitor detected more arrhythmia events compared with the Holter monitor over the total wear time (96 vs 61 events, p < 0.001), although the Holter monitor detected more events during the initial 24-h monitoring period (61 vs 52 events; p = 0.013). Novel, single-lead, intermediate-duration, user-friendly adhesive patch monitoring devices, such as the Zio Patch, represent the changing face of ambulatory ECG monitoring. However, the loss of quality, automated rhythm analysis and inability to detect myocardial ischemia continue to remain important issues that will need to be addressed prior to the implementation of these new devices.