Abstract 14766: Development of an Ex-Vivo Vascular Bioreactor to Investigate Viability of Coronary Arteries

Introduction: The cardiovascular disease that causes most of the deaths is atherosclerosis. The current research to assess efficacy of treatments is based on animal models, but these present several limitations related to time and costs associated. Ex-vivo systems represent useful models to study vascular biology and to test medical devices. The main goal of this research was to culture coronary arteries in an ex-vivo vascular bioreactor in order to maintain them alive and functional by mimicking physiological conditions. Methods: Culture experiments were performed on porcine right coronary arteries (RCA). Duration was set to 2 (n=3), 4 (n=3), and 9 days (n=3). The RCAs were dissected from hearts harvested from a local slaughterhouse. The bioreactor containing the dissected RCA was placed in a 38°C incubator. The RCA was cultured in a blood-mimicking culture medium. To assess RCA morphology and diameter, ultrasound imaging was performed. Pressure and flow rate were monitored daily. The flow rate was set to ensure a physiological peak endothelial shear stress of around 0.8-1.8 Pa. After 2, 4 or 9 days of culture, the RCA was embedded in paraffin and cut into 4 μm sections. Histological stainings (H&E and RF) were performed on the sections. Results: During RCA cultures, the mean pressure was 60-100 mmHg, and the peak flow rate was around 60 ml/min. Ultrasound imaging showed that the morphology and structure of cultured arteries was maintained during the culture. Histological analyses showed preserved endothelium and extracellular matrix. After 2 days of culture, endothelial coverage was not complete while after 4 days it was completely restored. After 9 days of culture, a layer of newly formed neointima was visible. Conclusions: The cultured RCAs maintained their physiological morphology up to 9 days of culture. The investigated model represents a useful tool for testing vascular therapies and devices, supporting the translational phase between in-vitro and in-vivo studies.