Changes in cardiac performance and sympathetic stimulation during and after fractionated radiotherapy in a rat model (original) (raw)

Physiological Interaction of Heart and Lung in Thoracic Irradiation

International journal of radiation oncology, biology, physics

INTRODUCTION: The risk of early radiation-induced lung toxicity (RILT) limits the dose and efficacy of radiation therapy of thoracic tumors. In addition to lung dose, coirradiation of the heart is a known risk factor in the development RILT. The aim of this study was to identify the underlying physiology of the interaction between lung and heart in thoracic irradiation. METHODS AND MATERIALS: Rat hearts, lungs, or both were irradiated to 20 Gy using high-precision proton beams. Cardiopulmonary performance was assessed using breathing rate measurements and F(18)-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) scans biweekly and left- and right-sided cardiac hemodynamic measurements and histopathology analysis at 8 weeks postirradiation. RESULTS: Two to 12 weeks after heart irradiation, a pronounced defect in the uptake of (18)F-FDG in the left ventricle (LV) was observed. At 8 weeks postirradiation, this coincided with LV perivascular fibrosis, an increase in LV end-d...

An overview of radiation-induced heart disease

Radiation Oncology Journal

Radiation therapy (RT) has dramatically improved cancer survival, leading to several inevitable complications. Unintentional irradiation of the heart can lead to radiation-induced heart disease (RIHD), including cardiomyopathy, pericarditis, coronary artery disease, valvular heart disease, and conduction system abnormalities. Furthermore, the development of RIHD is aggravated with the addition of chemotherapy. The screening, diagnosis, and follow-up for RIHD in patients who have undergone RT are described by the consensus guidelines from the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE). There is compelling evidence that chest RT can increase the risk of heart disease. Although the prevalence and severity of RIHD are likely to be reduced with modern RT techniques, the incidence of RIHD is expected to rise in cancer survivors who have been treated with old RT regimens. However, there remains a gap between guidelines and clin...