Antithrombotic Therapy in Kawasaki Disease

Kawasaki disease is an acute systemic vasculitis and leads to a hypercoagulable state caused by marked elevation of the platelet count, platelet activation, and endothelial dysfunction. Therefore, anti-inflammatory and antithrombotic therapy using intravenous immunoglobulin and aspirin is recommended as an initial treatment, although the debate on the efficacy and dosage of aspirin is still ongoing. Antithrombotic therapy is crucial in patients with coronary aneurysms because thrombosis is promoted in the acute and chronic phase of the disease and coronary thrombosis leads to fatal results. All the platelets, vascular endothelium, and clotting factors are involved in thrombosis in coronary aneurysms, thus combination therapy of antiplatelet and anticoagulant agents is essential. Generally, patients with giant aneurysms are recommended a combination of low-dose aspirin and warfarin regardless of coronary artery stenosis. In patients with an extraordinarily high risk of thrombosis, who have rapidly expanding coronary aneurysms or a recent history of coronary artery thrombosis, low molecular weight heparin (LMWH) instead of warfarin or triple therapy consisting of low-dose aspirin, clopidogrel, and warfarin can be considered. New drugs such as direct oral anticoagulants (DOACs) and abciximab are introduced in patients with Kawasaki disease, but further evidence on these patients is needed.