EFFECT OF RADIOTHERAPY ON HEART RATE REGULATION IN CANCER PATIENTS
The development of cardiovascular diseases (CVD) is one of the most frequent side effects in the treatment of patients with cancer as a result of the toxic effect of anticancer treatment on the function and structure of the heart or as a result of the accelerated development of CVD with existing cardiovascular risk factors. We studied the heart rate variability of patients with malignant neoplasms before and during radiation therapy. The tumor process causes a decrease in the level of the functional state and adaptive reserves. Radiation therapy causes an even greater decrease in the level of the functional state and activation of adaptive systemic reactions, followed by the development of a maladjustment reaction.