A crucial point of this research was the discovery of a myocardial support that we have termed cardiac fulcrum. The heart cannot be anatomically suspended and free in the thoracic cavity because it would be impossible to eject blood at a speed of 200 cm/s. Consequently, it was necessary for it to have a point of attachment, which was identified and called cardiac fulcrum (lever supporting point). In this supporting point, the muscle fibers are inserted in its structure of connective, chondroid or osseous nature, according to the specimens analyzed. All the hearts (bovine, porcine and human) studied in our investigations with anatomical and histological techniques certified this binding. The fibers that give origin to the myocardium, as well as those at its end, are attached to the fulcrum, leaving the rest of the muscular structure free in the mediastinum. Moreover, the cardiac fulcrum is seen in human adult and gestational ultrasounds, in computed tomography and magnetic resonance imaging.