Abstract

DI TORO, Darío; HADID, Claudio; GALLINO, Sebastián  and  LABADET, Carlos. Application and Comparison of the CHADS₂ and CHA₂DS₂-VASc Risk Scores in a Population with Atrial Fibrillation. Rev. argent. cardiol. [online]. 2013, vol.81, n.6, pp.493-497. ISSN 1850-3748.

Introduction The CHADS₂ score and the CHA₂DS₂-VASc score recently ad-opted by the medical community have been developed with international registry data and are widely used in clinical practice. However, they have not been evaluated in national registries. Objectives The aims of this study were first to evaluate the predictive power of the CHADS2 and CHA2DS2-VASc stroke risk scores in the Atrial Fibrillation Registry conducted by the Argentine Society of Cardiology Research Area and second to compare both scoring systems. Methods The Atrial Fibrillation Registry of 2001 was a multicenter, prospective study of all consecutive patients with chronic atrial fibrillation (permanent, persistent) treated in 70 medical centers in Argentina. Demographic data, socioeco-nomic characteristics, background and clinical features were obtained. A 2-year follow-up was performed to assess stroke rate. For the present analysis patients without anticoagulant treatment were selected. In this population, the two risk score systems were assessed; a ROC curve was built for each score (reported as c-statistic) and a comparison between both scoring systems was performed. Results The study population consisted of 303 patients (49.3%) not receiving anticoagulant therapy. The stroke rate in the se-lected population was 9.5%. Both scoring systems predicted significant stroke risk. The stroke rate increased as the CHADS₂ and the CHA₂DS₂-VASc scores were higher, and were similar in both risk scales. The CHADS₂ and CHA₂DS₂-VASc scores had c-statistic values of 0.67 (0.55-0.78) and 0.69 (0.59-0.78), respectively, without significant differences between them. The score analyses divided into three risk profiles -low, mod-erate and high- revealed that the predictive power decreased markedly. The c-statistic value of the CHADS₂ was 0.63 (95% CI 0.57-0.68) and that of the CHA₂DS₂-VASc score was 0.57 (95% CI 0.51-0.62), with a slightly better predictive trend for the CHADS₂ score but without statistical significance. Conclusions The two scoring systems used to predict stroke in an Argen-tine population of patients with persistent and permanent atrial fibrillation have a similar predictive power in accor-dance with results reported in the literature.

Keywords : Atrial Fibrillation; Embolism; Stroke.