Anticoagulants: a guide to starting oral anticoagulants in atrial fibrillation
People with non-valvular atrial fibrillation (AF) should be treated with oral anticoagulants based on their risk of stroke. Use this tool to identify patients with non-valvular AF for whom treatment with anticoagulants is recommended, and to personalise the selection of an oral anticoagulant in 3 easy steps:
Step 1: Patient assessment
Assess non-valvular AF patient’s risk of stroke using the CHADS
2 score calculator.
Congestive heart failure history
Hypertension (including well-controlled hypertension)
Age 75 years or older
Stroke or transient ischaemic attack history
Is the patient’s CHADS
2 score ≥ 1?
Step 2: Risk mitigation
Having determined that a patient needs anticoagulation:
Use the HAS-BLED chart below to identify correctable risk factors for bleeding:
Hypertension (systolic blood pressure > 160 mmHg)
Labile INRs (< 6 in 10 INRs in the therapeutic range)
Drugs (antiplatelet agents, NSAIDs, or alcohol ≥ 8 units per week).
Use the HAS-BLED chart to identify people at high risk of bleeding (with three or more HAS-BLED risk factors for bleeding) who need increased clinical monitoring.
These people may also benefit from twice annual Home Medicine Reviews (HMR).
Refer people with a history of intracranial haemorrhage to a specialist.
Do not use the HAS-BLED chart to exclude people from being treated with anticoagulants. People at high risk of bleeding are also at high risk of stroke.
H Hypertension (systolic blood pressure > 160 mm Hg)*
A Abnormal renal or liver function
S Stroke (history of)
B Bleeding (history of, or predisposition to bleeding)
L Labile INRs (<6 in 10 INRs in therapeutic range)*
E Elderly (e.g. age > 65 years)
D Drugs (antiplatelet agents, NSAIDs, or alcohol ≥ 8 units per week)*
*Correctable risk factors for bleeding.
Go to step 3
*Warfarin is contraindicated in people with severe active bleeding or with conditions associated with increased risk of severe bleeding (e.g. severe uncontrolled hypertension, recent gastrointestinal [GI] bleeding, genitourinary bleeding, active ulceration or severe thrombocytopenia as well as people with compliance problems (includes lack of access to INR monitoring as well as non adherence).