CHA2DS2-VASc score and fibrinogen concentration in patients with atrial fibrillation.

BACKGROUND: Assessment of thromboembolic risk is crucial in choosing appropriate treatment in atrial fibrillation (AF). Current guidelines recommend basing the decision on the CHA2DS2-VASc score. However, the score is based only on clinical parameters and therefore its relationship with laboratory-assessed coagulation status might not always be objective. OBJECTIVES: The aim of this study was to assess if the CHA2DS2-VASc score is associated with blood parameters in AF patients. MATERIAL AND METHODS: Patients with continuous AF prequalified for catheter ablation were enrolled into the study and had CHA2DS2-VASc calculated and blood taken for coagulation parameters. RESULTS: The study population comprised of 266 patients (65.0% males; age 57.6 ±10.1 years). Patients were divided into those with CHA2DS2-VASc score 0, and those with ≥1 points, respectively requiring and not requiring anticoagulation treatment. The group with CHA2DS2-VASc = 0 (12% of patients) compared to those with CHA2DS2-VASc ≥ 1 had a significantly lower fibrinogen concentration (285.6 ±82.0 vs 322.6 ±76.4 mg/dL; p = 0.02). Partial thromboplastin time was not significantly different between groups (p > 0.05). Differences were noticed in parameters concerning red blood cells. Lower risk patients had a lower red blood cell count (4.9 ±0.4 vs 5.1 ±6.0 106/μL); p = 0.03), higher hemoglobin concentration (14.9 ±1.0 vs 14.3 ±1.4 g/dL; p = 0.04), and higher hematocrit (43.5 ±2.6 vs 41.7 ±4.7%; p = 0.001). It was observed that along with the increase in CHA2DS2-VASc score mean fibrinogen concentration increased (p-value for trend = 0.04). CONCLUSIONS: In summary, a higher CHA2DS2-VASc score is independently associated with an increase in fibrinogen concentration. Further research is needed to assess the value of fibrinogen in thromboembolic risk assessment.