Adult patients with simple congenital heart disease (sACHD) represent an expanding population vulnerable to atrial arrhythmias (AA). CHA2DS2-VASc score estimates thromboembolic risk in non-valvular atrial fibrillation patients. We investigated the prognostic role of CHA2DS2-VASc score in a non-selected sACHD population regardless of cardiac rhythm. Between November 2009 and June 2018, 427 sACHD patients (377 in sinus rhythm, 50 in AA) were consecutively referred to our ACHD service. Cardiovascular hospitalization and/or all-cause death were considered as composite primary end-point. Patients were divided into group A with CHA2DS2-VASc score = 0 or 1 point, and group B with a score greater than 1 point. Group B included 197 patients (46%) who were older with larger prevalence of cardiovascular risk factors than group A. During a mean follow-up of 70 months (IQR 40–93), primary end-point occurred in 94 patients (22%): 72 (37%) in group B and 22 (10%, p < 0.001) in group A. Rate of death for all causes was also significantly higher in the group B than A (22% vs 2%, respectively, p < 0.001). Multivariable Cox regression analysis revealed that CHA2DS2-VASc score was independently related to the primary end-point (HR 1.84 [1.22–2.77], p = 0.004) together with retrospective AA, stroke/TIA/peripheral thromboembolism and diabetes. Furthermore, CHA2DS2-VASc score independently predicted primary end-point in the large subgroup of 377 patients with sinus rhythm (HR 2.79 [1.54–5.07], p = 0.01). In conclusion, CHA2DS2-VASc score accurately stratifies sACHD patients with different risk for adverse clinical events in the long term regardless of cardiac rhythm.
