In rheumatic mitral disease, we recommend
vitamin K antagonist (VKA)
therapy when the left atrial diameter is > 55 mm (Grade 2C) or when complicated by left atrial
thrombus (Grade 1A). In candidates for percutaneous mitral valvotomy with left atrial
thrombus, we recommend VKA
therapy until
thrombus resolution, and we recommend abandoning valvotomy if the
thrombus fails to resolve (Grade 1A). In patients with
patent foramen ovale (PFO) and
stroke or
transient ischemic attack, we recommend initial
aspirin therapy (Grade 1B) and suggest substitution of VKA if recurrence (Grade 2C). In patients with
cryptogenic stroke and DVT and a PFO, we recommend VKA
therapy for 3 months (Grade 1B) and consideration of PFO closure (Grade 2C). We recommend against the use of
anticoagulant (Grade 1C) and antiplatelet
therapy (Grade 1B) for native valve
endocarditis. We suggest holding VKA
therapy until the patient is stabilized without neurologic complications for
infective endocarditis of a prosthetic valve (Grade 2C). In the first 3 months after bioprosthetic valve implantation, we recommend
aspirin for aortic valves (Grade 2C), the addition of
clopidogrel to
aspirin if the aortic valve is transcatheter (Grade 2C), and VKA
therapy with a target international normalized ratio (INR) of 2.5 for mitral valves (Grade 2C). After 3 months, we suggest
aspirin therapy (Grade 2C). We recommend early bridging of mechanical valve patients to VKA
therapy with
unfractionated heparin (DVT dosing) or
low-molecular-weight heparin (Grade 2C). We recommend long-term VKA
therapy for all mechanical valves (Grade 1B): target INR 2.5 for aortic (Grade 1B) and 3.0 for mitral or double valve (Grade 2C). In patients with mechanical valves at low
bleeding risk, we suggest the addition of low-dose
aspirin (50-100 mg/d) (Grade 1B). In valve repair patients, we suggest
aspirin therapy (Grade 2C). In patients with thrombosed prosthetic valve, we recommend fibrinolysis for right-sided valves and left-sided valves with
thrombus area < 0.8 cm(2) (Grade 2C). For patients with left-sided prosthetic valve
thrombosis and
thrombus area ≥ 0.8 cm(2), we recommend early surgery (Grade 2C).
CONCLUSIONS: These antithrombotic guidelines provide recommendations based on the optimal balance of thrombotic and hemorrhagic risk.