Continuous monitoring versus HOLTER ECG for detection of atrial fibrillation in patients with stroke

Background and purpose: Detection of atrial fibrillation is of vital importance because oral anticoagulation decreases the risk of a stroke by 64%. Current standards for stroke unit treatment require continuous electrocardiogram (ECG) monitoring for at least 24 h. Additionally, a 24-h HOLTER ECG (HOLTER) should be performed in selected patients. It remains unclear whether continuous monitoring at the bedside is equivalent to HOLTER for the detection of atrial fibrillation. Furthermore, we investigate how many additional patients with paroxysmal atrial fibrillation can be identified as a result of a longer duration of continuous monitoring. Methods: In this study, we prospectively compared the detection rates of HOLTER and 24-h monitoring at the Stroke Unit at the University of Heidelberg over a period of 9 months. Continuous monitoring was analyzed by trained nurses, HOLTER by cardiologists. Results: We included 370 patients with ischemic stroke or transient ischemic attack (TIA) in our study. Of these, 192 patients underwent HOLTER. Previously unknown atrial fibrillation was detected in 44 patients, 13 patients had no atrial fibrillation in baseline ECG, but atrial fibrillation was detected by continuous monitoring. In two patients, the HOLTER showed atrial fibrillation; both patients had also been detected by continuous monitoring. Median time to detection of the atrial fibrillation during continuous monitoring was 43 h after hospitalization. Conclusion: In this study, use of HOLTER does not give any additional benefit in comparison with continuous monitoring with intermittent analysis by trained staff alone. The median detection time of 43 h emphasizes the importance of longer continuous monitoring.