Case Study: Anticoagulation

What is the main purpose of anticoagulants?

To reduce the risk of thrombus formation, especially in venous circulation.

What condition was the patient case based on?

Newly diagnosed atrial fibrillation (AF).

What score estimates stroke risk in AF patients?

CHA2DS2-VASc score.

What score estimates bleeding risk in AF patients?

HAS-BLED or ORBIT score.

Name four DOACs available in the UK.

Apixaban, Rivaroxaban, Edoxaban, Dabigatran.

What is the mechanism of action of Warfarin?

Vitamin K antagonist inhibiting clotting factors II, VII, IX, and X.

What is the mechanism of action of Apixaban, Rivaroxaban, and Edoxaban?

Direct reversible inhibitors of factor Xa.

What is the mechanism of action of Dabigatran?

Reversible inhibitor of thrombin.

What is the standard INR target range for most indications?

2.0–3.0 (target 2.5).

What reversal agent is used for Warfarin?

Vitamin K.

What reversal agent is used for Dabigatran?

Idarucizumab (Praxbind).

What reversal agent is used for Apixaban and Rivaroxaban?

Andexanet alfa.

Is there a reversal agent available for Edoxaban?

No, not currently.

When should DOAC monitoring (U&E, LFTs, FBC) be done?

At baseline, 1 month after starting, then every 3–6 months.

Which anticoagulant requires INR monitoring?

Warfarin.

What factors contraindicate anticoagulation?

Active bleeding, recent major surgery, severe liver disease, recent stroke, thrombocytopenia.

When is anticoagulation generally recommended in AF?

CHA2DS2-VASc ≥1 for males or ≥2 for females.

What is the benefit of DOACs over Warfarin?

Lower risk of intracranial bleeding, fewer food/drug interactions, reduced monitoring.

What major adverse effect is associated with all anticoagulants?

Bleeding.

What key counselling points must be given to patients starting anticoagulation?

Importance of adherence, bleeding signs, need for alert cards, and monitoring requirements.