Should We Judge Stroke Risk by Static or Dynamic Risk Scores? A Focus on the Dynamic Nature of Stroke and Bleeding Risks in Patients With Atrial Fibrillation.

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and a major risk factor for stroke. The number of patients with AF is predicted to increase in the next few decades. AF has also negative impact on quality of life as well as it significantly increases the risk of cardiovascular disease and overall mortality. Because the stroke is a pivotal outcome of AF, its prevention with the use of anticoagulation therapy constitutes an important component of AF management. The decision on oral anticoagulants' prescription should be based on appropriate risk stratification to allow for comprehensive assessment of benefit/hazard ratio of stroke and bleeding along with patients' preference. Several risk scores for stroke and bleeding as well as for stroke and systemic embolism have been developed, mainly in patients on vitamin K antagonists. AF guidelines stress the need for repetitive evaluation of thromboembolic and bleeding risks to tailor optimal AF management. Indeed, risk is not a static "one off" process and it should be adjusted for dynamic nature of risk factors. However, most risk scores are calculated according to baseline characteristics of patients, but the older the patients get, the more comorbidities they acquire, which influences stroke risk significantly. Hence, the default management of every patient with AF should include a regular reassessment of stroke and bleeding risk factors.