Effects of Chemotherapy Treatment on Metaboreflex, Mechanoreflex, and Baroreflex Function: PROTECT-08B Study

Breast cancer is the most common cancer worldwide, with over 2.2 million new cases diagnosed in 2020. Treatments such as chemotherapy often lead to a reduced exercise capacity, mainly due to cardiovascular and neuromuscular dysfunctions. This decline appears to be primarily caused by increased central fatigue, while peripheral fatigue remains unchanged. This imbalance suggests a hyperactivation of type III-IV afferent nerve fibers, which are involved in the metaboreflex-a mechanism that significantly influences cardiovascular responses during exercise. Two non-invasive methods, post-exercise circulatory occlusion (PECO) and passive leg movement (PLM), will be used to assess this hyperactivity in patients. Additionally, baroreflex function-crucial for regulating blood pressure-will be evaluated using a direct method to determine its sensitivity and reactivity. By comparing patients with healthy controls under submaximal stimuli, this study aims to better understand chemotherapy-induced cardiovascular dysfunctions. Ultimately, the goal is to design personalized exercise programs to restore cardiovascular function and reduce treatment-related side effects.