High-dose Radiation Induced Heart Damage in a Rat Model

Background/Aim: Radiation-induced heart disease (RIHD) is a concern during radiotherapy. For its comprehensive study, an in vivo selective heart irradiation model was developed. Materials and Methods: Sprague-Dawley rats were irradiated with 50 Gy and functional imaging, biochemical (circulating growth differentiation factor-15 (GDF-15), transforming growth factor-beta (TGFbeta) and morphological (picrosirius red staining of the heart) objectives were tested. Results: Signs and symptoms of RIHD occurred >12 weeks after irradiation with tachypnea, systolic and diastolic dysfunction, cardiac hypertrophy and body development retardation. Plasma GDF-15 was increased 3, 12 and 26, while plasma TGF-beta was increased 12 weeks after irradiation. At autopsy, extensive pleural fluid was found in the irradiated animals. Interstitial fibrosis could be reliably detected and quantified in irradiated hearts after a follow-up time of 19 weeks. Conclusion: The studied parameters could be used in future experiments for testing protective agents for prevention of radiation heart injury.