Myocardial Infarction in Children after COVID-19 and Risk Factors for Thrombosis

Acute myocardial infarction (AMI) in children is rather anecdotic. However, following COVID-19, some conditions may develop which may favor thrombosis, myocardial infarction, and death. Such a condition is Kawasaki-like disease (K-lD). K-lD appears in children as a subgroup of the multisystem inflammatory syndrome (MIS-C). In some cases, K-lD patients may develop giant coronary aneurysms. The evolution and characteristics of coronary aneurysms from K-lD appear to be different from classical Kawasaki disease (KD) aneurysms. Differences include a lower percentage of aneurysm formation than in non-COVID-19 KD, a smaller number of giant forms, a tendency towards aneurysm regression, and fewer thrombotic events associated with AMI. We present here a review of the literature on the thrombotic risks of post-COVID-19 coronary aneurysms, starting from a unique clinical case of a 2-year-old boy who developed multiple coronary aneurysms, followed by AMI. In dehydration conditions, 6 months after COVID-19, the boy developed anterior descending artery occlusion and a slow favorable outcome of the AMI after thrombolysis. This review establishes severity criteria and risk factors that predispose to thrombosis and AMI in post-COVID-19 patients. These may include dehydration, thrombophilia, congenital malformations, chronic inflammatory conditions, chronic kidney impairment, acute cardiac failure, and others. All these possible complications should be monitored during acute illness. Ischemic heart disease prevalence in children may increase in the post-COVID-19 era, due to an association between coronary aneurysm formation, thrombophilia, and other risk factors whose presence will make a difference in long-term prognosis.