BACKGROUND: There is no proven pharmacological strategy for the treatment of the failing systemic right ventricle (SRV) but myocardial fibrosis may play a role in its pathophysiology.
METHODS: We designed a double-blind, placebo-controlled clinical trial to assess the effects of eplerenone 50mg during 12 months on cardiac magnetic resonance parameters (SRV mass and ejection fraction) and neurohormonal and collagen turnover biomarker (CTB) levels.
RESULTS: Twenty six patients with atrial switch repair for transposition of the great arteries were randomized to eplerenone (n=14) or placebo (n=12) and 14 healthy volunteers served as controls for comparison of baseline neurohormones and CTB levels. The study population showed a good baseline profile in terms of SRV mass (57.4 ± 17 g/m(2)) and ejection fraction (54.9 ± 7.5%). However, levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), C terminal propeptide of type I procollagen (CICP) and C-terminal Telopeptide of type I Collagen (ICTP) were significantly elevated when compared to healthy controls. After one year of treatment, a trend toward reduction of CICP, N-terminal pro-Matrix Metalloproteinase 1 (NT-proMMP1), Tissue Inhibitor of Metalloproteinases 1 (TIMP1) and galectin 3 levels and a lower increase in ICTP in patients under eplerenone was observed. The reduction of SRV mass and the improvement of SRV function with eplerenone were not conclusive.
CONCLUSIONS: Patients with SRV treated with eplerenone showed an improvement of an altered baseline CTB profile suggesting that reduction of myocardial fibrosis might be a therapeutic target in these patients.
