The CHA2DS2-VASc Score for Risk Stratification of Stroke in Heart Failure With-vs-Without Atrial Fibrillation

Abstract

A recent study suggested that the CHA2DS2-VASc score can risk stratify heart failure (HF) patients without atrial fibrillation (AF) for stroke. We performed a retrospective analysis using the national Veteran Affairs database to externally validate the findings. Crude incidence rates of end points were calculated. A Cox proportional model was used to study the association between the CHA2DS2-VASc score and outcomes. In HF patients with AF (n = 17,481) and without AF (n = 36,935), the 1 year incidence rate for ischemic stroke, thromboembolism, thromboembolism (without MI), and death were 2.7 and 2.0%; 10.3 and 7.9%; 4.1 and 3.1%; and 19.2 and 26.0%, respectively, with higher rates with increasing CHA2DS2-VASc scores both with and without AF. CHA2DS2-VASc score predicted strokes in HF patients without AF (1-year C-statistic 0.62, 95% CI 0.60-0.64; NPV 85.4%, 95% CI 83.4-87.4%) with similar predictive ability to those with AF (C-statistic 0.59, 95% CI 0.56-0.62; NPV 86.4%, 95% CI 82.6-90.2%). Among patients with HF, there was an increased risk of stroke, thromboembolism, and death with increasing CHA2DS2-VASc scores regardless of AF status. Our findings support the use of the CHA2DS2-VASc score as a prognostic tool in HF.