COL4A1 and viral myocarditis: It has been reported that miRNA-543 downregulated SIRT1/AMPK/ NF-Kappab signaling pathway to reduce inflammatory response and myocardial injury in children with viral myocarditis.[37] MiRNA-543 mediated COL4A1 expression in exosomes derived from human mesenchymal stem cells to promote angiogenesis of cardiac microvascular endothelial cells after myocardial infarction.[38] The above studies suggest that miRNA-543 may be involved in the formation of cardiovascular diseases, but no relevant reports have been reported in AAA.