To determine the effect of MR and heart failure on the gene expression of PPAR signaling pathway, we compared the expression profile by PCR assay in the left atria of MR patients with heart failure (n = 5) to normal controls (n = 3; 76-year-old Caucasian female, 24-year-old Caucasian male and 27-year-old Caucasian male, purchased from BioChain, Newark, CA, USA). This evidence concerns the gene PPARA and miotic rate.