Background: The CHA₂DS₂-VASc score has been shown to predict systemic thromboembolism and mortality in certain groups in sinus rhythm (SR), similar to its predictive value with atrial fibrillation (AF).

Objectives: To compare factors of inflammation, thrombosis, platelet reactivity, and turnover in patients with high versus low CHA₂DS₂-VASc score in SR.

Methods: We enrolled consecutive patients in SR and no history of AF. Blood samples were collected for neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), immature platelet fraction (IPF%) and count (IPC), CD40 ligand, soluble P-selectin (sP-selectin) and E-selectin. IPF was measured by autoanalyzer and the other factors by ELISA.

Results: The study comprised 108 patients (age 58 ± 18 years, 63 women (58%), 28 (26%) with diabetes), In addition, 52 had high CHA₂DS₂-VASc score (³ 2 for male and ³ 3 for female) and 56 had low score. Patients with low scores were younger, with fewer co-morbidities, and smaller left atrial size. sP-selectin was higher in the high CHA₂DS₂-VASc group (45, interquartile ratio [IQR] 36–49) vs. 37 (IQR 28–46) ng/ml, P = 0.041]. Inflammatory markers were also elevated, CRP 3.1 mg/L (IQR 1.7–9.3) vs. 1.6 (IQR 0.78–5.4), P < 0.001; NLR 2.7 (IQR 2.1–3.8) vs. 2.1 (IQR 1.6–2.5), P = 0.001, respectively. There was no difference in E-selectin, CD40 ligand, IPC, or IPF% between the groups.

Conclusions: Patients in SR with high CHA₂DS₂-VASc score have higher inflammatory markers and sP-selectin. These findings may explain the higher rate of adverse cardiovascular events associated with elevated CHA₂DS₂-VASc score.