Thromboembolic and hemorrhagic risk stratification in patients with atrial fibrillation. Part I: the thromboembolic risk

Atrial fibrillation, whose prevalence is in constant increase, is associated to a noticeably greater thrombo-embolic risk. Various associated factors, such as older age, arterial hypertension, heart failure, previous cerebrovascular events (stroke and transient ischemic attacks), diabetes mellitus, female sex and vascular diseases determine a further increase of the risk of stroke in patients with atrial fibrillation. Robust evidence exists on the efficacy of traditional anticoagulant oral therapy in the prevention of thrombo-embolic risk in these patients, but fears and concerns of hemorrhagic events for the physicians and the logistic difficulties related to the periodic International Normalized Ratio evaluation for the patients are at the basis of a noticeable under-utilization of the therapy with vitamin K antagonists in the real world. Stratification of the thrombo-embolic risk has thus particular importance; for this scope we may use now score systems as CHA2DS2 and, above all, CHA2DS2-Vasc, that allows the identification of truly low risk patients, which do not require an antithrombotic treatment. Novel oral anticoagulants, lastly, will help physicians in order to obtain a better management of trombo-embolic risk in atrial fibrillation.