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CLINICAL STATEMENTS AND GUIDELINES

Circulation. 2024;149:e1–e156. DOI: 10.1161/CIR.0000000000001193 January 2, 2024 e29

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

management program specific to AF was associated with proportionately more days alive and out of hospital but not prolonged event-free survival relative to standard management.12 On the other hand, data on technology-based clinical decision support systems are mixed, with a reduction in stroke and thromboembolism in the mAF-App 2 (Mobile Health Technology for Improved Screening and Optimized Integrated Care in Atrial Fibrillation) trial5 and improved anticoagulation use in the CDS-AF (clinical decision support tool for stroke prevention) trial,6 but no significant effect on primary outcomes in 3 other randomized trials.13–15 Educational interventions for both providers and patients can improve use of anticoagulation.16

6 PREVENTION OF THROMBOEMBOLISM

6.1 Risk Stratification Schemes

Recommendations for Risk Stratification Schemes Referenced studies that support the recommendations are summarized in the Online Data Supplement. COR LOE Recommendations

1 B-NR 1 Patients with AF should be evaluated for their annual

risk of thromboembolic events using a validated clinical risk score, such as CHA2DS2-VASc.1–4

1 B-NR 2 Patients with AF should be evaluated for factors that

specifically indicate a higher risk of bleeding, such as previous bleeding and use of drugs that increase bleeding risk, in order to identify possible interventions to prevent bleeding on anticoagulation.5–7

2a C-LD 3 Patients with AF at intermediate annual risk of

thromboembolic events by risk scores (eg, equivalent to CHA2DS2-VASc score of 1 in men or 2 in women), who remain uncertain about the benefit of anticoagulation, can benefit from consideration of factors that might modify their risk of stroke to help inform the decision.*

3: No Benefit B-NR 4.	 In patients who are deemed at high risk for stroke,

bleeding risk scores should not be used in isolation to determine eligibility for oral anticoagulation but instead to identify and modify bleeding risk factors and to inform medical decision-making.8–10

*Factors may include AF burden or other features in Table 3. Synopsis Patients with AF have an increased risk of stroke that varies widely among individuals. Several risk scores based on clinical factors have been developed.1–3 Risk scores should be evaluated using accepted criteria11: their ability to discriminate between high- and low-risk individuals (eg, as assessed by the c-index), their accurate calibration to actual risk levels, and their validation in independent populations. A patient’s absolute risk of stroke is central to recommendations about anticoagulation and can be characterized as low (∼<1%/y), intermediate (∼1 to ∼2%/y), and high (∼>2%/y). Currently used risk scores discriminate moderately well between patients at higher and lower risk yet can greatly overes- timate or underestimate absolute risk levels4 in different populations. Current risk scores may be inaccurate because they omit other factors that alter risk of stroke, especially characteristics of AF12–14; consequently, risk scores should be calibrated against the actual annual rates of stroke in the target population to assure an accurate, unbiased risk prediction. Newer risk scores may modestly improve risk discrimination (c-index) compared with CHA2DS2-VASc and may offer potential advantages in specific populations (Table 8). Online calculators are available for the ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation),1 CHA2DS2-VASc,2 and GARFIELD-AF3 (Global Anticoagulant Registry in the Field-Atrial Fibrillation) risk scores.

Anticoagulation increases the risk of bleeding, so patients with AF are generally evaluated for bleeding risk as part of SDM about anticoagulation. Currently used bleeding risk scores—HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio [INR], elderly [age ≥65 years], drugs/alcohol concomitantly]),5 HEMORR2HAGES (hepatic or renal disease, ethanol abuse, malignancy, older age [≥75 years], reduced platelet count or function, re-bleeding risk, hypertension [uncontrolled], anemia, genetic factors, excessive fall risk, stroke),6 and ATRIA (anemia, renal disease, elderly [age ≥75 years], any prior bleeding, hypertension)7—discriminate poorly between patients with and without bleeding15 and include many nonspecific factors that predict an increased risk of stroke as well as an increased risk of bleeding (eg, age, hypertension, renal disease, and previous stroke). Assessment of factors that specifically predict an increased risk of bleeding without predicting an increased risk of stroke is more helpful when balancing risks and benefits of anticoagulation.

Recommendation-Specific Supportive Text 1.	 Several risk scores based on clinical factors have

been developed1–3; in general, risk discrimination is improved by including more predictors (eg, CHA2DS2-VASc improved on the original CHADS2

2 [congestive heart failure, hypertension, age >75 years, diabetes, stroke/transient ischemia attack/ thromboembolism] by adding additional risk factors and age categories). However, the absolute risk associated with any particular score level varies widely across populations; among 15 cohort studies, patients with a CHA2DS2-VASc score of 2 had annual rates of stroke that ranged from low to high: <1% in 4 cohorts, 1% to 2% in 6 cohorts, and >2% in 5 cohorts,4 although higher scores were associated with higher stroke risk in each cohort (Figure 9). The CHA2DS2-VASc score is considered the most validated score, most therapies have used that score to prove efficacy, and thus CHA2DS2-VASc is generally the preferred score.

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