The percentage of B1 cells in the DCM group was negatively correlated with NT-proBNP levels (R = -0.532, P < 0.01), positively correlated with the LVEF (R = 0.457, P = 0.02), and not correlated with hs-CRP levels (R = 0.248, P = 0.21) (Fig. 7A–C). This evidence concerns the gene NPPB and familial dilated cardiomyopathy.