REN and endothelial dysfunction: These include activation of the renin–angiotensin–aldosterone system (RAAS), chronic systemic inflammation, oxidative stress, endothelial dysfunction, and disturbances in calcium-phosphate homeostasis—all of which contribute to vascular calcification, arterial stiffness, and accelerated coronary atherosclerosis, thereby impairing myocardial perfusion and cardiac function [24].