Circulating microRNA profiling in serum of pediatric patients with heart failure submitted to VAD implant

Background: There is an increasing interest on the role of circulating miRNAs (c-miRNAs)as biomarkers for diagnosis and prognosis of disease. In adult HF patients treated with VAD, changes in c-miRNAs levels have been observed. To date there are no data regarding c-miRNAs changes and role in pediatric patients with HF. Purpose: Aims of this study were to examine: the profile of c-miRNAs in HF children; the effects of VAD on the c-miRNAs levels; and to identify potential targets of selected c-miRNAs. Methods: Blood samples were collected from 5 pediatric patients [13±6 (mean±SD) months, 17±2 LVEF%] with HF before and at 4 hrs, 1, 3, 7, 14 and 30 days after VAD implant. C-miRNA profile at VAD implant and after 30 days was determined by NGS. Modified c-miRNA were validated by qRT-PCR and assessed in blood samples collected during time-course after VAD implant. Putative miRNA targets were selected using miRWalk database. Results: After NGS, a total of 169 c-miRNAs were detected in serum samples of HF pediatric patients. N=13 c-miRNAs were simultaneously modulated at 30 days after VAD implant compared to pre-VAD. Among them, only 6 c-miRNAs were confirmed by qRT-PCR. Putative targets of selected c-miRNAs seem to be involved with a synergistic effect in the hemostatic process.