New insights into the pathogenic mechanisms and treatment of arterial thrombosis in antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is a systemic disorder clinically characterized by widespread thrombosis and obstetric complications associated with the persistent presence of antiphospholipid antibodies (aPLs). The persistent presence of aPLs represents a thrombotic risk in APS, which can be stratified according to the aPL profile. Thrombosis occurs in both arteries and veins. Notably, arterial thromboses have a higher recurrence compared with venous thromboses and a tendency for recurrence in the same vascular (arterial) site. Secondary prevention of arterial thrombosis requires more intensive treatment than prevention of venous thrombosis. Data from randomized clinical trials indicated that factor Xa inhibitors should not be recommended for APS. Recurrent thromboses in patients with APS treated with factor Xa inhibitors were mainly arterial, with a high rate of stroke. Dual antiplatelet therapy may have some benefit for preventing the recurrence of arterial thrombosis in patients with APS. This review article describes pathogenic mechanisms, clinical features, risk assessment, and management of arterial thrombosis in patients with APS. Particularly, we discuss how secondary prophylaxis may be a useful approach to reduce the occurrence of arterial thrombosis.