The rapid knowledge in the field of neuro-humoral regulation of cardiovascular pathophysiology is changing the picture of current diagnosis and treatment of cardiac patients. The emerging conceptual revolutionary idea is that heart acts not as a pump, merely, but as a "gland", that is as a regulator of circulatory homeostasis and salt-water balance. Cardiovascular pathophysiology has to be written, indeed, on this basis: this physiology textbook gives an up-to-date description of the complexity and novelty of actual knowledge, with all its potential clinical implications.