MFN2 and hydrops fetalis: For example, mitochondrial fission is triggered by the descending effect of hyperglycemia and insulin signaling pathway in diabetic cardiomyopathy; while in IRI, mitochondrial fission is mainly caused by Ca2+ overload and increased ROS production; while in HF, insufficient mitochondrial autophagy induced by Mfn2 and abnormal expression of OPA1 will lead to abnormal accumulation of mitochondrial fragment.