The association between mental stress and cardiac function has always been of major interest. In the 19th century, Claude Bernard, the father of evidence-based medicine, first acknowledged the vagus nerve as a structural and functional link connecting the heart and the brain. Nowadays, stress is considered one of the most significant health problems in modern society, related to the physiopathology of psychiatric, metabolic and cardiovascular diseases, and the search for its biomarkers remains a challenging task for researchers and clinicians. […]