Effectiveness and safety of dual antiplatelet therapy in coronary aneurysms caused by Kawasaki disease in children: study protocol for a multicenter randomized clinical trial

Background: Medium or large coronary artery aneurysm (CAA) is a serious complication of Kawasaki disease (KD) and may cause thrombosis, coronary artery stenosis, and even myocardial infarction at different stages of the disease. Dual antiplatelet therapy (aspirin plus clopidogrel) is considered for prophylaxis of coronary thrombosis in KD presenting with more than medium CAAs based on adult coronary artery disease experience and expert consensus. This paper describes the study protocol for a randomized controlled trial that measures the clinical effectiveness and safety of dual antiplatelet therapy in the thromboprophylactic treatment of KD.

Methods: The present study is a multicenter, open-label, randomized controlled trial (RCT) with a 12-month follow-up. KD patients with medium or large CAAs (Z-value ≥5), evaluated by echocardiogram and clinicians before treatment, are randomized in a 1:1 ratio and assigned to aspirin therapy alone (Control group), or dual antiplatelet (aspirin plus clopidogrel) therapy (Experimental group). Antiplatelet therapy is given to the KD patients from the time of diagnosis until the coronary artery returns to normal. Weekly or monthly follow-up visits are conducted to record compliance, recovery, and biochemical indicators and continue for one year. The primary outcome is the incidence of thrombus throughout the disease and the effective of dual antiplatelet. The secondary outcomes are the safety of dual antiplatelet drugs, platelet-related indicators, inflammatory indicators, biochemical indexes and drug-related indicators during the study period. Patients who do not meet the inclusion criteria of the RCT trial or those unwilling to provide informed consent enter the registration trial.

Discussion: This is the first study to evaluate the effectiveness and safety of dual antiplatelet therapy in coronary aneurysms caused by Kawasaki disease in children. It is hoped that this study will play an important and significant role in improving the prognosis and long-term quality of life for children with KD complicated by CAAs.

Trial registration: Chinese Clinical Trial Registry, ChiCTR1800019181. Registered on Oct 30, 2018.