- See also: Atrial fibrillation anticoagulation
The CHA2DS2-VASc score [Congestive heart failure, Hypertension, Age ≥75 years (doubled), Diabetes mellitus, Stroke (doubled), Vascular disease, Age 65–74 years, Sex category] predicts clinical risk of stroke and thromboembolism in atrial fibrillation.
The CHA2DS2-VASc score has been recommended in the 2010 European Society of Cardiology (ESC) guidelines  which promotes a risk factor based approach to stroke prevention, and de-emphasises the artificial stratification into low/moderate/high risk, given the poor predictive value of these 3 categories.
Indeed, the CHA2DS2-VASc score is more inclusive of 'stroke risk modifier' risk factors and has been validated in several large independent cohorts  . Of note, the most recent validation study used nationwide data on 73,538 hospitalized non-anticoagulated patients with AF, whereby in ‘low risk’ subjects (score=0), the rate of thromboembolism per 100 person-years was 1.67 (95%CI 1.47 to 1.89) with CHADS2 and 0.78 (0.58 to 1.04) with the CHA2DS2-VASc score, at 1 year follow-up . Thus, those categorised as ‘low risk’ using the CHA2DS2-VASc score were ‘truly low risk’ for thromboembolism, and the CHA2DS2-VASc score performed better than CHADS2 in identifying these 'low risk' patients. The c-statistics at 10 years follow-up were 0.812 (0.796 to 0.827) with CHADS2 and 0.888 (0.875 to 0.900) with the CHA2DS2-VASc score, respectively - thus, the CHA2DS2-VASc score also performed better than CHADS2 in predicting ‘high risk’ patients.
|Feature||Score if present|
|Congestive Heart Failure||1|
|Age ≥ 75 years||2|
|Age between 65 and 74 years||1|
|Vascular disease (previous MI, peripheral arterial disease or aortic plaque)||1|
Anticoagulation based on the CHA2DS2-VASc score
Patients with a CHA2DS2-VASc of two or more may benefit from chronic anticoagulation according to American Heart Association clinical practice guidelines. The following table shows treatment strategies are recommended in the table below based on the European Society of Cardiology guidelines:
|0||Low||No antithrombotic therapy (or Aspirin)||No antithrombotic therapy (or Aspirin 75-325mg daily)|
|1||Moderate||Oral anticoagulation||Oral anticoagulation, whether as warfarin INR to 2.0-3.0, or one of the new oral anticoagulation drugs (eg. dabigatran) [or aspirin 75-325mg daily, depending on factors such as patient preference]|
|2 or greater||High||Oral anticoagulation||Oral anticoagulation, whether as Warfarin INR to 2.0-3.0, or one of the new oral anticoagulation drugs (eg. dabigatran), unless contraindicated (e.g. clinically significant GI bleeding, etc)|
Assessment of Bleeding Risk with Anticoagulation
The decision to anticoagulate a patient should also be based upon an assessment of the risk of bleeding using a score such as the HAS-BLED score.
2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation (DO NOT EDIT)
Prevention of Thromboembolism
Risk-Based Antithrombotic Therapy
- See also: CHA2DS2-VASc Score
|"1. Selection of antithrombotic therapy should be based on the risk of thromboembolism irrespective of whether the AF pattern is paroxysmal, persistent, or permanent. (Level of Evidence: B) "|
|"2. In patients with nonvalvular AF, the CHA2DS2-VASc score is recommended for assessment of stroke risk. (Level of Evidence: B) "|
|"3. For patients with nonvalvular AF with prior stroke, transient ischemic attack (TIA), or a CHA2DS2-VASc score of 2 or greater, oral anticoagulants are recommended. Options include: warfarin (INR 2.0 to 3.0) (Level of Evidence: A), dabigatran (Level of Evidence: B), rivaroxaban (Level of Evidence: B), or apixaban (Level of Evidence: B)."|
|"4. Re-evaluation of the need for and choice of antithrombotic therapy at periodic intervals is recommended to reassess stroke and bleeding risks. (Level of Evidence: C) "|
|"5. For patients with atrial flutter, antithrombotic therapy is recommended according to the same risk profile used for AF. (Level of Evidence: C) "|
|"1. For patients with nonvalvular AF and a CHA2DS2-VASc score of 0, it is reasonable to omit antithrombotic therapy. (Level of Evidence: B) "|
|"1. For patients with nonvalvular AF and a CHA2DS2-VASc score of 1, no antithrombotic therapy or treatment with an oral anticoagulant or aspirin may be considered. (Level of Evidence: C) "|
|"2. For patients with nonvalvular AF and moderate-to-severe CKD with CHA2DS2-VASc scores of 2 or greater, treatment with reduced doses of direct thrombin or factor Xa inhibitors may be considered (e.g., dabigatran, rivaroxaban, or apixaban), but safety and efficacy have not been established. (Level of Evidence: C) "|
|"3. Following coronary revascularization (percutaneous or surgical) in patients with AF and a CHA2DS2-VASc score of 2 or greater, it may be reasonable to use clopidogrel (75 mg once daily) concurrently with oral anticoagulants but without aspirin. (Level of Evidence: B) "|
- Lip GY, Nieuwlaat R, Pisters R, Lane DA, Crijns HJ. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest. 2010 Feb; 137(2):263-72.(Link to article – subscription may be required.)
- Camm AJ, Kirchhof P, Lip GY, Schotten U, Savelieva I, Ernst S, Van Gelder IC, Al-Attar N, Hindricks G, Prendergast B, Heidbuchel H, Alfieri O, Angelini A, Atar D, Colonna P, De Caterina R, De Sutter J, Goette A, Gorenek B, Heldal M, Hohloser SH, Kolh P, Le Heuzey JY, Ponikowski P, Rutten FH. Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Eur Heart J. 2010 Oct;31(19):2369-429.
- Van Staa TP, Setakis E, Di Tanna GL, Lane DA, Lip GY. A comparison of risk stratification schema for stroke in 79884 atrial fibrillation patients in general practice. J Thromb Haemost. 2010 Oct 1. doi: 10.1111/j.1538-7836.2010.04085.x.[Epub ahead of print] PubMed PMID: 21029359.
- Lip GY, Frison L, Halperin JL, Lane DA. Identifying Patients at High Risk for Stroke Despite Anticoagulation. A Comparison of Contemporary Stroke Risk Stratification Schemes in an Anticoagulated Atrial Fibrillation Cohort. Stroke. 2010 Oct 21. [Epub ahead of print] PubMed PMID: 20966417
- Olesen JB, Lip GY, Hansen ML, Hansen PR, Tolstrup JS, Lindhardsen J, Selmer C, Ahlehoff O, Olsen AM, Gislason GH, Torp-Pedersen C. Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study. BMJ. 2011 Jan 31;342:d124. doi: 10.1136/bmj.d124.
- January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JC et al. (2014). "2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society.". Circulation 130 (23): 2071-104. doi:10.1161/CIR.0000000000000040. PMID 24682348.
- Camm AJ, Lip GY, De Caterina R, Savelieva I, Atar D, Hohnloser SH et al. (2012). "2012 focused update of the ESC Guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation--developed with the special contribution of the European Heart Rhythm Association.". Europace 14 (10): 1385-413. doi:10.1093/europace/eus305. PMID 22923145.
- (2014) "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society". Circulation. doi:10.1161/CIR.0000000000000041. ISSN 0009-7322.