Impact of cardiac fibrosis and collagens on right ventricular failure and acute kidney injury in patients after continuous-flow left ventricular assist devices.

OBJECTIVES: We aim to investigate the impact of cardiac fibrosis and collagens on right ventricular failure (RVF) and acute kidney injury (AKI) in patients receiving continuous flow left ventricular assist devices.
METHODS: Heart tissues from 34 patients were obtained from continuous flow left ventricular assist device insertion sites and corresponding clinical data were collected. The participants were divided into 2 groups according to the extent of the cardiac fibrosis or collagens.
RESULTS: Overall, 18 patients developed RVF with 14 receiving right ventricular assist device (RVAD), and 22 patients developed AKI with 12 needing new-onset renal replacement therapy. Higher collagen I (Col1) was significantly associated with increased incidences of RVF (76.5% vs 29.4%, P = 0.015), RVAD support (64.7% vs 17.6%, P = 0.013) and stage 3 AKI (58.8% vs 17.6%, P = 0.032), and patients with higher Col1 were more prone to renal replacement therapy (52.9% vs 17.6%, P = 0.071). Receiver operating characteristic curves showed that Col1 had good predictive effects on RVF [area under the curve (AUC) = 0.806, P = 0.002], RVAD support (AUC = 0.789, P = 0.005), stage 3 AKI (AUC = 0.740, P = 0.020) and renal replacement therapy (AUC = 0.731, P = 0.028) after continuous-flow left ventricular assist device. Moreover, patients with higher Col1 had significantly longer postoperative duration of mechanical ventilation, duration of intensive care unit stay and hospital length of stay (all P < 0.05). Cardiac fibrosis, collagen III (Col3) and Col1/Col3 shared similar results or trends with Col1.
CONCLUSIONS: Cardiac fibrosis and related collagens in the apical left ventricular tissue are associated with increased risks of RVF, RVAD use and worse renal function. Further study is warranted owing to the small sample size.