Management of atrial high-rate episodes detected by cardiac implanted electronic devices

• Published in: Nature reviews cardiology Vol. 14; no. 12; pp. 701 - 714
• Main Authors: Freedman, Ben, Boriani, Giuseppe, Glotzer, Taya V., Healey, Jeff S., Kirchhof, Paulus, Potpara, Tatjana S.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.12.2017; Nature Publishing Group
• Subjects: 692/4019/592/75/29/1309; 692/499; 692/700/565/2773; Atrial Fibrillation - physiopathology; Atrial Fibrillation - therapy; Cardiac Imaging; Cardiac Surgery; Cardiology; Cardiovascular implants; Defibrillators, Implantable; Disease Management; Electrocardiography; Health aspects; Heart Atria - physiopathology; Heart Rate - physiology; Humans; Medicine & Public Health; Pacemaker, Artificial; Prevention; review-article; Risk Factors; Stroke
• DOI: 10.1038/nrcardio.2017.94
• ISSN: 1759-5002

Key Points Cardiac electronic implanted devices (CIEDs) readily detect atrial high-rate episodes (AHREs), which are fairly common and associated with an increased incidence of clinical atrial fibrillation, stroke, and systemic thromboembolism Up to 20% of automatically detected AHREs reflect something other than an atrial arrhythmia, and inspection of the atrial electrogram is required for verification The absolute risk of stroke associated with AHRE detection is lower than in patients with clinical atrial fibrillation who have similar clinical risk factors for stroke The temporal relationship between AHREs and stroke is poor in most patients with a CIED who develop a stroke In ∼15% of patients with stroke and a high AHRE burden, a close temporal relationship exists between the AHREs and stroke, which declines after 5 days Two large clinical trials of anticoagulant drugs in CIED-detected AHREs are ongoing; their outcomes will inform future management Cardiac implanted electronic devices (CIEDs) frequently detect subclinical atrial high-rate episodes (AHREs), but the relevance and appropriate clinical response to these episodes is uncertain. In this Review, Freedman and colleagues discuss the relationship between AHREs, atrial fibrillation, and risk of stroke, and propose a management algorithm for patients with CIED-detected AHREs. Cardiac implanted electronic devices (CIEDs), including pacemakers and implantable defibrillators that perform atrial sensing typically using an atrial electrode, frequently detect subclinical atrial high-rate episodes (AHREs). When the intracardiac electrograms are carefully examined, the majority of AHREs are atrial fibrillation (AF) or other atrial tachyarrhythmias, which have been shown to be associated with both an increased risk of stroke, and subsequent development of clinical AF. However, the absolute risk of stroke among patients with AHREs is less than might be expected for clinically diagnosed paroxysmal AF. In addition, a close temporal relationship between AHREs and stroke is seen in only 15% of strokes in patients with a CIED: the majority have either no AHREs before the stroke, or AHREs very distant from incident stroke, suggesting that AHREs might be more of a risk marker than a risk factor for stroke. Management of AHREs should not be the same as for clinical AF, and a degree of uncertainty underpins the rationale for much-needed, ongoing, randomized trials of oral anticoagulation in patients with CIED-detected AHREs. We propose a management algorithm that takes into account both the stroke risk and the AHRE burden, but highlights the current uncertainty and evidence gaps for this condition.