Previous studies have shown that CircHIPK3 not only acts as a sponge of miR‐29b‐3p to inhibit its expression and upregulates that of downstream target genes, such as Col1a1 and Col3a1, thereby improving myocardial fibrosis in DCM through competitive endogenous RNA (ceRNA) mechanism, but also exerts a ceRNA mechanism by acting as a sponge of miR‐30a to block its function. The gene discussed is COL3A1; the disease is familial dilated cardiomyopathy.