1. INTRODUCTION
Kawasaki disease (KD) is a systemic inflammatory condition occurring predominantly in children (80% of patients are younger than 5 years of age), first reported in 1974 as an acute febrile illness with muco-cutaneous lesions and lymphadenopathy [1, 2]. The incidence of KD varies across the world from 19 to 265 cases per 100,000 in children less than 5 years of age [2]. It can be complicated by a systemic vasculitis with particular involvement of the coronary arteries, if left untreated 20% of children could develop coronary artery aneurysm [2]. In the acute phase of the disease inflammatory formation of coronary aneurysms can occur, eventually associated with rupture of the latter, while thrombosis or narrowing of the affected coronary arteries can complicate the late phases [2-6]. In high income countries KD remains the leading cause of acquired heart disease in children, with complication such as acute myocardial infarction [2, 7-9]. Despite extraordinary results due to early recognition of the disease and treatment with intra-venous administration of immunoglobulins [2, 10], long-term studies showed that complications secondary to inflammation and aneurysmatic dilatation of the coronary arteries can still occur, with subsequent impairment of the left ventricular function [2, 8, 9, 11-14]. Selective coronary angiography is indispensable in those situations to provide essential information for the decision making, before percutaneous or surgical myocardial revascularization [2, 14-17]. Coronary artery bypass graft (CABG) is performed in the presence of inflammation and aneurysms of the coronary arteries, using both arterial and/or venous grafts [17, 18]. In literature only retrospective studies about CABG after KD are found and no meta-analysis has been published until now: grafts’ patency and long-term outcomes such as survival rates appear uncertain. Since the risk of progression of the systemic arteritis with formation of aneurysms in other arterial districts [19], such as internal thoracic artery (ITA) [20], the choice of the best type of surgical revascularization is still a matter of discussions [18].
The objectives of our study were to assess which surgical strategy of CABG provides better graft patency and short and long-term outcomes, through a literature systematic review and a Bayesian network meta-analysis. A PICOS study design was displayed in Supplementary Table 1. Primary endpoint is graft patency for ITAs, saphenous veins (SV) and other conduits (gastroepiploic [GEA] and radial [RA] arteries). Secondary endpoints were early mortality, need for interventional procedures and surgical re-interventions, and long-term mortality for arterial, venous or mixed (arterial plus second venous graft) types of revascularization.