What are the indications for Rivaroxaban (Xarelto) 15mg daily and Aspirin (ASA) 81mg daily?

Rivaroxaban 15mg Daily and Aspirin 81mg Daily: Clinical Indications

The combination of rivaroxaban 15mg daily and aspirin 81mg daily is indicated for patients with atrial fibrillation who have undergone percutaneous coronary intervention (PCI) with stenting, as a reduced-intensity dual antithrombotic regimen to balance stroke prevention and bleeding risk. 1

Primary Indication: Atrial Fibrillation with PCI

For patients with nonvalvular atrial fibrillation undergoing PCI:

• Rivaroxaban 15mg once daily (or 10mg if CrCl 30-50 mL/min) plus a P2Y12 inhibitor (preferably clopidogrel) is recommended as an alternative to triple therapy (warfarin + dual antiplatelet therapy) 1
• This regimen should be used instead of the standard 20mg daily dose when combined with antiplatelet agents 1
• The combination significantly reduces clinically significant bleeding compared to warfarin-based triple therapy while maintaining similar efficacy for preventing thrombotic events 1, 2

Duration of therapy:

• Continue for 12 months post-PCI in most patients 1
• After completing dual therapy, transition to oral anticoagulation alone 1

Secondary Indication: Stable Coronary Artery Disease (Alternative Regimen)

For patients with stable CAD at high ischemic risk and low bleeding risk:

• Rivaroxaban 2.5mg twice daily (NOT 15mg daily) plus aspirin 100mg daily is the evidence-based regimen 3, 4
• This "vascular dose" combination reduces major adverse cardiovascular events by 24% compared to aspirin alone 3, 4
• The 15mg daily dose is NOT indicated for this population without concomitant atrial fibrillation 1, 3

Critical Dosing Distinctions

The 15mg daily dose specifically applies to:

• Atrial fibrillation patients on antiplatelet therapy (stroke prevention dose when combined with antiplatelets) 1, 5
• Patients with moderate renal impairment (CrCl 15-50 mL/min) requiring anticoagulation for AF 1, 5, 6

This differs from:

• Standard AF stroke prevention: 20mg daily (without antiplatelet therapy) 1
• VTE treatment: 20mg daily maintenance dose (NOT 15mg) 1
• Stable CAD without AF: 2.5mg twice daily plus aspirin 3, 4

Renal Function Considerations

Dose adjustment based on creatinine clearance:

• CrCl ≥50 mL/min: Standard dosing applies 5
• CrCl 30-50 mL/min: Reduce to 15mg daily for AF patients 1, 5, 6
• CrCl 15-30 mL/min: 15mg daily may be considered but requires close monitoring 1, 6
• CrCl <15 mL/min or dialysis: Avoid use due to lack of safety data 1, 6

Contraindications and Precautions

Absolute contraindications for this combination:

• Valvular atrial fibrillation (mechanical valves, moderate-severe mitral stenosis, hemodynamically significant valve disease) - warfarin is required instead 7
• Active pathological bleeding 6
• Severe hepatic impairment 6

Bleeding risk management:

• Major bleeding increases by 66% compared to aspirin alone in stable CAD populations 3
• Gastrointestinal bleeding is the most common site 1, 3
• Routine proton pump inhibitor use is recommended 1
• Avoid NSAIDs and other antiplatelet agents beyond the prescribed regimen 1

Clinical Scenarios Where This Regimen Should NOT Be Used

Do not use rivaroxaban 15mg + aspirin 81mg for:

• Acute coronary syndrome within the first 1-6 months (requires triple therapy initially) 1
• Stable CAD without atrial fibrillation (use 2.5mg BID rivaroxaban + aspirin instead) 3, 4
• VTE treatment (requires 20mg daily, not 15mg) 1
• High bleeding risk patients with AF post-PCI (consider rivaroxaban monotherapy without aspirin) 1

Monitoring Requirements

Essential monitoring parameters:

• Assess renal function at baseline and annually (more frequently if CrCl 30-50 mL/min: 2-3 times yearly) 5
• Evaluate for signs of bleeding at each visit 6
• No routine coagulation monitoring (INR, aPTT) is required or reliable for rivaroxaban 6

Administration Specifics

Key administration details:

• Take rivaroxaban 15mg once daily with the evening meal to ensure adequate absorption 1, 6
• Aspirin 81mg can be taken at any time of day 6
• If a dose is missed, take as soon as remembered on the same day; do not double dose 6