Warfarin or anticoagulation is a big topic, with lots of new information about it and we are moving away from warfarin to novel or direct oral anticoagulants. These are pills that need much less monitoring. Regular injections are needed to monitor levels with Warfarin, but these tablets do not require that rigorous level of monitoring. There is a certain type of cardioembolic called atrial fibrillation or an irregular heartbeat, which predisposes people to an increased risk of clots. For every other type of mini stroke or stroke, we would give aspirin or clopidogrel which are anti platelet, but for atrial fibrillation those medications are not thought to be effective and medications like warfarin or these new anticoagulants are thought to be to be much better at reducing the risk of stroke.  In fact, we think that they reduce the risk of stroke in patients with atrial fibrillation by up to two thirds.