Stroke risk scores to predict hospitalization for acute decompensated heart failure in atrial fibrillation patients

Introduction. Atrial fibrillation (AF) is the most frequent hospitalized arrhythmia. It associates increased risk of death, stroke and heart failure (HF). Stroke risk scores, especially CHA₂DS₂-VASc, have been applied also for populations with different diseases. There is, however, limited data focusing on the ability of these scores to predict HF decompensation.

Methods. We conducted a retrospective observational study on a cohort of 204 patients admitted for cardiovascular pathology to the Cardiology Ward of our tertiary University Hospital. We aimed to determine whether the stroke risk scores could predict hospitalisations for acute decompensated HF in AF patients.

Results. C-statistics for CHADS₂ and R₂CHADS₂ showed a modest predictive ability for hospitalisation with decompensated HF (CHADS₂: AUC 0.631 p = 0.003; 95%CI 0.560–0.697. R₂CHADS₂: AUC 0.619; 95%CI 0.548–0.686; p = 0.004), a marginal correlation for CHA₂DS_2-VASc (AUC 0.572 95%CI 0.501-0.641 with a p value of only 0.09, while the other scores failed to show a correlation. A CHADS₂ ≥ 2 showed a RR = 2.96, p<0.0001 for decompensated HF compared to a score <2. For R₂CHADS₂ ≥ 2, RR = 2.41, p = 0.001 compared to a score <2. For CHA₂DS_2-VASc ≥ 2 RR = 2.18 p = 0.1, compared to CHA₂DS₂-VASc <2. The correlation coefficients showed a weak correlation for CHADS₂ (r = 0.216; p = 0.001) and even weaker for R₂CHADS₂ (r = 0.197; p = 0.0047 and CHA₂DS₂-VASc (r = 0.14; p = 0.035).

Conclusions. Among AF patients, CHADS_2, CHA₂DS₂-VASc and R₂CHADS₂ were associated with the risk of hospitalisation for decompensated HF while ABC and ATRIA failed to show an association. However, predictive accuracy was modest and the clinical utility for this outcome remains to be determined.