Indications and Duration of Therapy

Recommended Therapeutic Range and Duration of Therapy with Warfarin

Adapted from the 9th Edition of the CHEST guidelines:

Indication INR Range Duration
Antiphospholipid Syndrome 2.0-3.0 indefinite (2B)
DVT and PE
Transient/reversible risk factor 2.0-3.0 3 months (1B)
Unprovoked 2.0-3.0 at least 3 months (1B) then reevaluate
Second episode of unprovoked 2.0-3.0 extended (1B)
Non-Valvular Atrial Fibrillation/Atrial Flutter
CHADS2 = 0 (low CVA risk) N/A no therapy (2B) or ASA 75-325mg (2B)
CHADS2 = 1 (intermediate CVA risk) N/A  dabigatran (2B)
CHADS2 ≥ 2 (high CVA risk) N/A dabigatran (2B)
With mitral stenosis 2.0-3.0 long-term (1B)
With stable CAD 2.0-3.0 long-term (2C)
Prior to/following cardioversion to NSR 2.0-3.0 3 weeks/4weeks (1B)
Mechanical Heart Valve
Aortic 2.0-3.0 long-term (1B)
Mitral 2.5-3.5 long-term (2C)
Bioprosthetic heart valve
Aortic N/A aspirin 50-100mg (2C)
Mitral 2.0-3.0 3 months then switch to ASA (2C)
Cardioembolic Ischemic Stroke N/A dabigatran (2B)

Reference:

Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines 2012

Strength of Recommendations Grading System

 

 

From the 8th edition of the CHEST guidelines:

 

Indication INR Range Duration
Antiphospholipid Syndrome
No additional risk factors 2.0-3.0 indefinite (1A)
Recurrent events with therapeutic INRs 2.5-3.5 indefinite (2C)
DVT and PE
Transient/reversible risk factor 2.0-3.0 3 months (1A)
Unprovoked 2.0-3.0 at least 3 months (1A) then reevaluate (1C)
Second episode of unprovoked 2.0-3.0 long-term (1A)
After 3 months at 2.0-3.0 1.5-1.9 long-term (1A)
With active cancer after LMWH for 3-6 months 2.0-3.0 indefinite (1A) or until CA resolved (1C)
Atrial Fibrillation/Atrial Flutter
With prior CVA/TIA or systemic embolism 2.0-3.0 long-term (1A)
CHADS2 = 0 N/A aspirin 75-325mg (1B)
CHADS2 = 1 2.0-3.0 long-term (1A) or aspirin 75-325mg (1B)
CHADS2 ≥ 2 2.0-3.0 long-term (1A)
With mitral stenosis 2.0-3.0 long-term (1B)
Following open heart surgery 2.0-3.0 4 weeks (1B)
Prior to/following cardioversion to NSR 2.0-3.0 3 weeks/4weeks (1C)
Mechanical Heart Valve
Aortic bileaflet or tilting disk 2.0-3.0 long-term (1B)
Mitral bileaflet or tilting disk 2.5-3.5 long-term (1B)
Aortic or mitral caged ball or caged disk 2.5-3.5 long-term (1B)
Any valve with additional risk factor 2.5-3.5 long-term (1B)
Any valve + suffer embolism with target INR increase + add ASA long-term (2C)
Bioprosthetic heart valve
Aortic N/A aspirin 50-100mg
Mitral 2.0-3.0 3 months then switch to ASA (1B)
With prior h/o systemic embolism 2.0-3.0 3 months then reassess (1C)
With LA thrombus 2.0-3.0 until resolution (1C)
Cardioembolic Ischemic Stroke 2.0-3.0 long-term (1A)