p.40 抽出テキスト

CLINICAL STATEMENTS AND GUIDELINES

January 2, 2024 Circulation. 2024;149:e1–e156. DOI: 10.1161/CIR.0000000000001193 e40

Joglar et al 2023 Guideline for the Diagnosis and Management of Atrial Fibrillation

Synopsis Approximately 25% to 30% of ischemic strokes remain cryptogenic after standard stroke evaluation.2,3 A large proportion of these events are presumed to be related to occult AF, particularly those of embolic appearance.4,5 APT is the recommended treatment of choice for patients with cryptogenic stroke, including embolic stroke of undetermined source.6,7 For patients with AF in general, however, anticoagulation has been shown to be superior to APT for stroke risk reduction.8 Thus, detection of occult AF after stroke may have significant therapeutic implications. Randomized trials have shown longer durations of cardiac monitoring result in higher rates of AF detection after stroke.1,9,10 However, data are limited regarding the effects of extended monitoring on risk reduction of recurrent stroke or poststroke mortality. For recommendations on anticoagulation and risk factors, refer to Section 6.4.1 (“Oral Anticoagulants”). Recommendation-Specific Supportive Text 1.	 Growing evidence supports the use of extended

cardiac monitoring for the identification of occult AF in patients with cryptogenic stroke.11,12 In the EMBRACE (30 Day Event Monitoring Belt for Recording Atrial Fibrillation After a Cerebral Ischemic Event) trial, which randomized 572 patients ≥55 years of age with recent cryptogenic stroke or TIA to either 30-day external loop recorder or conventional 24-hour Holter monitoring, extended monitoring was associated with higher rates of AF detection at 90 days.1The CRYSTAL-AF (Cryptogenic Stroke and Underlying AF) trial randomized 441 patients ≥40 years of age with recent cryptogenic stroke or TIA to cardiac monitoring with either insertable loop recorder or conventional follow-up ECGs. Implantable recorder was superior in detecting AF at 6 months (8.9% versus 1.4%), 12 months (12.4% versus 2.0%), and 3 years (30% versus 3%).9 In FIND-AF (Future Innovations in Novel Detection of Atrial Fibrillation), which compared repeated sets of 10-day Holter monitoring (at baseline, 3-month, and 6-month timepoints) to conventional 24-Holter in patients ≥60 years of age with recent stroke, higher rates of detection were associated with repeated monitoring (14% versus 5%; absolute difference, 9.0% [95% CI, 3.4-14.5]; P=0.002).10 Finally, the PER DIEM (Post-Embolic Rhythm Detection with Implantable vs External Monitoring) RCT also showed a significantly greater proportion of patients with AF detected at 1 year with prolonged monitoring.13 Additional studies are needed, however, to determine whether extended cardiac monitoring improves long-term poststroke outcomes. 6.4.1. Oral Anticoagulation for Device-Detected Atrial High-Rate Episodes Among Patients Without a Previous Diagnosis of AF

Recommendations for Oral Anticoagulation for Device-Detected Atrial High-Rate Episodes Among Patients Without a Previous Diagnosis of AF Referenced studies that support the recommendations are summarized in the Online Data Supplement. COR LOE Recommendations

2a B-NR 1 For patients with a device-detected atrial high-rate

episode (AHRE) lasting ≥24 hours1 and with a CHA2DS2-VASc score ≥2 or equivalent stroke risk,2 it is reasonable to initiate oral anticoagulation3 within a SDM framework that considers episode duration and individual patient risk.

2b B-NR 2 For patients with a device-detected AHRE last-

ing between 5 minutes and 24 hours and with a CHA2DS2-VASc score ≥3 or equivalent stroke risk,2 it may be reasonable to initiate anticoagulation within a SDM framework that considers episode duration and individual patient risk.

3: No Benefit B-NR 3 Patients with a device-detected AHRE lasting

<5 minutes and without another indication for oral anticoagulation should not receive oral anticoagulation.4,5

Synopsis AHREs detected by a cardiovascular implantable electronic device are associated with a stroke risk lower than that of clinical AF6 that varies according to the episode duration1 and CHA2DS2-VASc score.2 Clinician confirmation of the duration and nature of the longest atrial high-rate episode is recommended.1 Episodes lasting ≥24 hours are associated with a significant risk of stroke or systemic embolism1,7 that may be reduced with oral anticoagulation.3 By contrast, short episodes, commonly defined as <5 minutes, are not associated with clinical events.4,5 Patients with episodes of intermediate duration and with an elevated stroke risk may benefit from oral anticoagulation.2 There is an interaction between AHRE duration and CHA2DS2-VASc score,2 suggesting both may be used to guide oral anticoagulation candidacy (Figure 12). Of note, the threshold for anticoagulation is higher as in device-detected AF the risk of stroke may be lower than in clinical AF.

Recommendation-Specific Supportive Text 1.	 AHREs lasting ≥24 hours are associated with

an elevated risk of stroke that varies according to CHA2DS2-VASc score. AHRE burden is most commonly defined according to the duration of the longest-detected episode, though cumulative duration has also been examined. In a secondary analysis of the ASSERT (Atrial Fibrillation Reduction Atrial Pacing Trial), adjudicated AHREs >24 hours was associated with an increased risk of subsequent stroke or systemic embolism (adjusted HR, 3.24 [95% CI, 1.51-6.95]; P=0.003).1 Similar findings are seen in observational studies in which most AHREs

Downloaded from http://ahajournals.org by on October 7, 2026