Cardiovascular System Involvement

Since Kawasaki disease (KD) was described by Japanese doctor Tomisaku Kawasaki in 1967, KD has replaced rheumatic heart disease becomes the leading cause of acquired heart disease in children in the developed world (Shulman, Clin Immunol Immunopathol 53(2 Pt 2):S141–S146, 1989). Although its etiology is not yet understood, it has been generally recognized as an acute vasculitis happening in children with allergies, mostly less than 5 years old (Maddox et al. Pediatr Int. 57:1116–1120, 2015). Because coronary artery injury is the most serious complication, coronary artery thrombus can lead to coronary heart disease and even sudden death. Therefore, more and more pediatric cardiologists are engaged in diagnosis, treatment and follow-up of KD, therefore, the vast majority of children with KD have a good outcome. However, clinic symptoms of KD vary, and multiple systems can be involved. In the case of the cardiovascular system alone KD may complicated with myocarditis (Aggarwal et al. Indian J Pediatr 79(6):813–814, 2012; De Rosa et al. Reumatismo 70(2):115–116, 2018), myocardial damage, pericardial effusion (Okada et al. Scand J Rheumatol. 44(3):247–252, 2015), cardiomyopathy (Komaki et al. Cardiol Young 28(6):890–893, 2018), CRBBB, ABV, arrhythmia (Sumitomo et al. Circ J 72(2):274–280, 2008), even shock (Li et al. Pediatr Rheumatol Online J 17(1):1, 2019) and so on. Coronary artery dilation and aneurysm dilation are more common complications in KD. In my center, total three misdiagnosed children developed CAA and coronary artery thrombus, coronary heart disease and lost their younger lives. KD accompany with myocarditis has been reported previously and reports of myocardial biopsies perform early in the disease course suggested a nearly universal incidence (Yutani et al. Arch Pathol Lab Med 105:470–473, 1981). In those KD patients with CAA, the myocardium damage was very popular although without any symptom (Yonesaka et al. Cardiol Young. 20(6):602–609, 2010). Thus, we can explain the chronic myocardial damage in KD without CAA.