Algorithm
Choosing the appropriate anticoagulant
This part of the website is aimed at aiding doctors (especially GPs) to help facilitate and guide the decision to prescribe anticoagulation for patients with a new diagnosis of atrial fibrillation. Please click the start button to begin.
Patient Details
Date of birth
Gender
Weight
Suspected or diagnosed non-valvular atrial fibrillation?
Please answer all the questions
As non-valvular atrial fibrillation is not suspected or diagnosed, this tool isn't appropriate for this patient
Chads2Vasc2 Score
When to use
The CHA2DS2-VASc score is one of several risk stratification schema that can help determine the 1 year risk of a TE event in a non-ant coagulated patient with non-valvular AF. The CHA2DS2-VASc score, among other risk stratification schema, can be used to provide an idea of a patient’s risk for TE event.
Why use
Helps calculate the risk of stroke in an patient with Atrial fibrillation.
Congestive Heart Failure / or left ventricular failure?
Hypertension?
If any features of Stroke/TIA/ TE?
Vascular Disease? (e.g. previous MI peripheral arterial disease or Aortic plaque)
Diabetes Mellitus?
HAS-BLED Bleeding risk score
When to use
The HAS-BLED score was developed as a practical risk score to estimate the 1-year risk for major bleeding in patients with atrial fibrillation. Major bleeding defined as any bleeding requiring hospitalization, and/or causing a decrease in haemoglobin level > 2 g/L, and/or requiring blood transfusion that was not haemorrhagic stroke. Consider using the HAS-BLED score as a tool to potentially guide the decision to start anticoagulation in patients with atrial fibrillation. Consider comparing the risk for major bleeding as calculated by the HAS-BLED score to the risk for thromboembolic events by the CHADS2 or CHA2DS2-VASc to determine if the benefit of anti-coagulation outweighs the risk.
Uncontrolled Hypertension?
Eg. systolic blood pressure > 160mmHg.
Abnormal Renal Function?
Chronic dialysis, renal transplantation or serum creatinine ≥ 200 micromol/L.:
Abnormal Liver Function?
Chronic hepatic disease (eg. cirrhosis) or biochemical evidence of significant hepatic derangement (eg. bilirubin >2 x ULN, in association with AST/ALT/ALP >3 x ULN, etc.):
Stroke?
Bleeding?
Previous bleeding history and/or predisposition to bleeding, eg. bleeding diathesis, anaemia, etc.
Labile INRs (if taking VKA)?
Unstable/high INRs or poor time in therapeutic range (eg. <60%).
Elderly?
Eg. Age >65 years, frail condition.
Antiplatelet Drugs?
Concomitant use of aspirin, other antiplatelet drug or NSAID, etc.
Alcohol Abuse?
Special Contraindications
Uncontrolled Hypertension?
Eg. systolic blood pressure > 160mmHg.
Infect endocarditis?
Pregnancy / breast feeding?
Moderate to severe mitral stenosis?
Prosthetic valve?
Has the patient a known bleeding disorder?
Has the patient thrombocytopenia (platelet count <100 x 109/L)?
Has the patient active clinically significant bleeding?
Has the patient had a recent haemorrhagic stroke within the last 4 weeks?
Has the patient had recent neurosurgery / spinal surgery within the last 4 weeks?
Does the patient have hepatic impairment?
Is the hepatic impairment or liver disease expected to have any impact on survival?
Is the hepatic disease associated with coagulopathy and clinically relevant bleeding risk?
Calculates CrCl according to the Cockcroft-Gault equation
Weight
Creatinine
| Renal/ ml |
Apixaban 5mg BD |
Rivaroxaban 20mg OD |
Dabigatran 150mg BD |
Edoxaban 60mg OD |
|---|---|---|---|---|
| 50-30ml | No change | 15 mg OD |
150mg BD Reduce to 110mg BD if high risk of bleeding |
Reduce to 30 mg OD |
| 30ml-15ml | No change | 15 mg OD | Contraindicated | Reduce to 30 mg OD |
| 15ml > | Not recommended | Not recommended | Contraindicated | Not recommended |
