Perspective:

The following are 10 points to remember from this review of the role of ambulatory electrocardiographic monitoring (AECGM) in patients with atrial fibrillation (AF):

1. The devices for AECGM available in clinical practice consist of 24- to 48-hour Holter monitors, leadless event monitors, patient-activated loop monitors, 21- to 30-day auto-triggered loop monitors, 7- to 14-day extended Holter monitors, and ambulatory telemetry monitors; the most appropriate device for a given patient depends on the clinical indication for monitoring.

2. In patients with intermittent symptoms suggestive of AF, AECGM is useful for ruling in or ruling out AF.

3. AECGM for 21-30 days is indicated to screen for AF as a cause of thromboembolism in patients with cryptogenic strokes.

4. When otherwise unclear, AECGM is useful for clarifying whether AF is paroxysmal or persistent.

5. AECGM for 24 hours allows for accurate assessment of the efficacy of a rate control strategy.

6. In patients with documented or suspected bradycardia or sick sinus syndrome, AECGM is helpful for documenting the severity of bradycardia or sinus pauses.

7. Because the goal of rhythm-control drug therapy is improvement in symptoms and not the complete suppression of AF, AECGM has limited value for assessing the efficacy of antiarrhythmic drug therapy.

8. After catheter ablation of AF, AECGM is useful for determining the cause of residual symptoms, detecting asymptomatic AF, and confirming efficacy.

9. The threshold amount of AF detected by AECGM that places a patient at risk of stroke is not established.

10. AECGM is of value for detecting fusion or pseudo-fusion between paced and intrinsic beats as an explanation for inefficacy in patients who do not respond to cardiac resynchronization therapy.