Effects of eplerenone on markers of myocardial fibrosis, 6-minute walk distance, and quality of life in adults with tetralogy of Fallot and complete transposition of the great arteries.

Ventricular dysfunction is common among patients with repaired cyanotic congenital heart disease. To date, no pharmacologic intervention has been demonstrated to be beneficial in this setting. To begin addressing this knowledge gap, we conducted a single-center prospective, randomized, open-label pilot study to investigate the effects of eplerenone on serologic markers of collagen turnover and inflammation, 6-minute walk distance, and quality of life in patients with tetralogy of Fallot (TOF) or transposition of the great arteries with a systemic right ventricle (transposition of the great arteries [TGA]). Patients were randomized to a 3-month drug-free period at the beginning of the treatment period or at the end. All patients received 12 months of eplerenone therapy during the treatment period. Twenty-six patients were enrolled in the trial; 17 completed the study protocol: 8 with TOF and 9 with TGV. Eplerenone had no effect on serum levels of procollagen 1 N-terminal peptide (PINP), procollagen 3 N-terminal peptide (PIIINP), or galectin-3 (G3). Similarly, eplerenone had no effect on 6-minute walk distance or quality of life. In conclusion, PINP and PIIINP levels are as high as or higher in patients with TOF and TGA than in patients with normal cardiac anatomy and heart failure, whereas G3 levels are lower. Eplerenone is well tolerated by adults born with congenital heart disease.