Thromboembolic events in atrial fibrillation: Different level of risk and pattern between peripheral artery disease and coronary artery disease.

BACKGROUND: The existence of vascular disease in patients with atrial fibrillation (AF) is associated with an increased risk of thromboembolic events. It is unclear whether coronary artery disease (CAD) and/or peripheral artery disease (PAD) have similar presentations and complication rates. AIM: To investigate thromboembolic events among patients with AF who have CAD, PAD or polyvascular disease. METHODS: Patients with a new diagnosis of AF without anticoagulation (n=306,386) were identified from the National Health Insurance Research Database in Taiwan (2001-2013). Ischaemic stroke (IS), systemic thromboembolism (STE) and their combination (IS/STE) were compared in four groups (No-CAD/PAD, CAD-only, PAD-only, CAD+PAD), and secondarily in patients with only CAD versus only PAD. Last, we compared propensity score-matched patients with only CAD or PAD with those with CAD and PAD. RESULTS: There were 185,169 patients without CAD or PAD, 8113 patients with only PAD, 105,715 patients with only CAD, and 7389 patients with CAD and PAD eligible for analysis (mean±SD follow-up 3.2±3.2 years). The incidences of STE and IS/STE differed in the four groups, with the highest in the CAD+PAD group and the lowest in the No-CAD/PAD group. The proportions of IS and STE also varied, with higher proportions of STE in patients with PAD, but higher proportions of IS in patients with CAD. After propensity score matching, the PAD-only group had significantly higher incidences of STE and IS/STE than the CAD-only group, across all levels of CHA2DS2-VASc score. Patients with CAD and PAD had a significantly higher incidence of STE and IS/STE than propensity score-matched patients with CAD or PAD. CONCLUSIONS: PAD or CAD in patients with AF did not contribute equally to the risk prediction and presentation of IS and STE. Patients with polyvascular disease should be considered at higher risk than those with either condition.