Predictive value of the CHA2DS2-VASc score in atrial fibrillation patients at high risk for stroke despite oral anticoagulation

Abstract

Introduction and objectives: The risk of stroke in atrial fibrillation is heterogeneous and depends upon underlying clinical conditions included in current risk stratification schemes. Recently, the CHA(2)DS(2)-VASc score has been included in guidelines to be more inclusive of common stroke risk factors seen in everyday clinical practice, and useful in defining "truly low risk" subjects. We aimed to assess the usefulness of CHA(2)DS(2)-VASc score to give us an additional prognostic perspective for adverse events and mortality among "real world" anticoagulated patients with atrial fibrillation who are often elderly with many comorbidities.

Methods: Consecutive outpatients with permanent/paroxysmal nonvalvular atrial fibrillation with CHA(2)DS(2)-VASc≥2 and stabilized oral anticoagulation (international normalized ratio 2.0-3.0) for at least the preceding 6 months were recruited. Patients with CHA(2)DS(2)-VASc≥2 were selected. Adverse cardiovascular events including stroke, acute coronary syndrome, or heart failure; major bleeds; and mortality were recorded during more than 2.5-year-follow-up.

Results: Of 933 patients (93.5%) assessed, 432 were males, median age 76 (71-81) years. After a follow-up of 946 (782-1068) days, 109 patients (11.7%) had adverse cardiovascular events, 80 patients (8.6%) had major bleeds, 101 patients (10.8%) died, and 230 (24.6%) had major adverse events (composite end-point). Increasing CHA(2)DS(2)-VASc score by 1 point had a significant impact on the occurrence of cardiovascular events (hazard ratio=1.27; 95% confidence interval, 1.13-1.44; P<.001), mortality (hazard ratio=1.36; 95% confidence interval, 1.19-1.54; P<.001); and major adverse events (hazard ratio=1.23; 95% confidence interval, 1.13-1.34; P<.001). CHA(2)DS(2)-VASc score was not associated with major bleeding episodes.

Conclusions: Among high risk atrial fibrillation patients on oral anticoagulation, CHA(2)DS(2)-VASc successfully predicts cardiovascular events and mortality, but not major bleeds.