We also constructed a protein-protein interaction network of ferroptosis related differentially expressed genes by STRING (Figure 3), and 10 hub genes for ferroptosis in ischemic cardiomyopathy: HSPA9, FASN, HSPB1, EIF4A1, ATF4, MAP1LC3B, HSP90B1, MYC, PLIN2, MYH10, and were identified by Cytoscape (Figure 4A). The gene discussed is ATF4; the disease is ischemic cardiomyopathy.