Detecting AF with Long-Term Monitoring
There are a variety of monitoring methods used to detect atrial fibrillation in practice today:
Intermittent and Symptom-based Monitoring:
- EKG
- Holter monitor
- External loop recorder
Long-term Monitoring:
Insertable cardiac monitor
You may be surprised to learn that intermittent and symptom-based monitoring is highly inaccurate for identifying patients with any or long-duration atrial tachycardia/atrial fibrillation (AT/AF) and for assessing AT/AF burden.1 In fact, the more complex and longer the method of (external) monitoring that is used, the lower the patient compliance.2 How can you improve AF detection? Studies show that in cryptogenic stroke patients, longer monitoring increases AF detection. In the studies highlighted in the chart below, notice the percentage of patients with detected AF compared to monitoring duration:
| Author | Monitor Type | % Patients with Dectected AF | Definition of AF |
|---|---|---|---|
| Jabaudon3 | 24-hour Holter | 5% | No defined duration |
| Bansil4 | 48-hour Holter | 5% | No defined duration |
| Jabaudon3 | 7-day Holter | 5.7% | No defined duration |
| Tayal5 | 21-day Monitor | 23% | 85% of episodes less than or equal to 30 seconds of duration |
| Zeigler6 | 1.2-years Continuous Monitoring | 28% | 5 min. duration |
In one recent study, the majority of newly detected AF patients (73%) had AT/AF on <10% of follow-up days, making it highly unlikely to be detected by standard monitoring techniques.6
1. Ziegler P. Comparison of continuous versus intermittent monitoring of atrial arrhythmias. Heart Rhythm 2006;3:1445–1452.
2. Calkins, et al. Heart Rhythm. Jun 2007;4(6):816-61.
3. Jabaudon D, Sztajzel J, Sievert K, Landis T, Sztajzel R. Usefulness of ambulatory 7-day ECG monitoring for the detection of atrial fibrillation and flutter after acute stroke and transient ischemic attack. Stroke. July 2004; 35(7): 1647-1651. Originally published online May 20, 2004.
4. Bansil S, Karim H. Detection of atrial fibrillation in patients with acute stroke. J Stroke Cerebrovasc Dis. 2004;13:12-15.
5. Tayal,et al. Neurology 2008;71:1-1.
Be Informed
Hear what your colleagues are saying about Cryptogenic Stroke
and AF