<Internation Circulation>:Could you please talk about the optimal strategy of antithrombotic treatment of Atrial Fibrillation?

prof.Weitz:We first have to do risk stratification to determine the patient’s  risk of stroke.  Often， the CHADS2 score is used for this purpose. If the CHADS2 score is 1， the annual risk of stroke is about 2%; in such patients we  discuss the risk versus benefits of anticoagulation therapy versus antiplatelet therapy.  If the  CHADS2 score is 2 or higher， the annular risk of stroke is about 4% or more and such patients require long-term anticoagulation therapy to reduce this risk. At the moment， all we have to offer are the vitamin K antagonists， such as  warfarin.  We will have – we hope， very soon – other alternatives.