Thromboembolic and hemorrhagic risk stratification in patients with atrial fibrillation. Part II: hemorrhagic risk and guidelines recommendations

Robust evidence exists on the efficacy of traditional anticoagulant oral therapy in the prevention of thrombo-embolic risk in patients with non valvular atrial fibrillation, but fears and concerns of hemorrhagic events for the physicians and 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 hemorrhagic risk has, thus, particular importance; for this objective we may use now several score system, among whom the more suggested is the HAS-BLED, with the principal aim to select and trait modifiable risk factors for bleeding. These score systems have been evaluated in some recent clinical trials. During the last years, a number of national and international guidelines on the prevention of the thrombo-embolic risk in patients with non valvular atrial fibrillation have been updated. These guidelines, generally, recommend the use of the CHA2DS2VaSC score for the evaluation of the thrombo-embolick risk, and of the HAS-BLED score for the evaluation of the hemorrhagic one. The consequent risk stratification is fundamental as a clinical guide for the use of oral anticoagulant therapy.