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Objective: The cardiac muscle cannot be anatomically free in the thorax and without a support to fulfill its hemodynamic function. Therefore, the possibility of the existence of a support point acting as a lever was analyzed. Material and methods: A total of 77 hearts from the morgue and slaughterhouses were used: a. 56 from two-year-old bovids weighing between 1300-1900 g (average 1650 g); b. 17 human (three from 8-, 16-, and 23-week gestation embryos, respectively; four from 30- and 36-day, and 10 and 27-week infants; two from 4-year-old and 10-year- old children; and eight from adults with an average weight of 300 g); c. 4 from pigs (400 g). Anatomical, histological, histochemical and radiological studies were carried out. The heart was fixed in 10% buffered formalin. Histological studies were done using hematoxylin-eosin and Masson’s trichrome staining techniques and four-micron sections. Immunomarking (s100- neurofilaments) was also performed. The myocardial band was unwound completely. The myocardial band was uncoiled in its entirety. The extracted pieces were analyzed for anatomy and histology. The investigation was completed with simple radiographic imaging studies, magnetic resonance imaging and computed tomography. Results: In anatomical investigations we have found in all human and bovine hearts studied a nucleus underlying the right trigone of bonechondroid-tendinous histological structure. Microscopic analysis revealed in bovine hearts a trabecular osteochondral matrix [fulcrum]. In all human hearts the fulcrum was found to be formed by chondroid tissue. In this structure, not described by other authors, the origin and end of the myocardial fibers have muscular insertion. Imaging techniques confirmed its existence. Conclusions: The cardiac fulcrum found in the anatomical investigation of human and bovine hearts would clarify about the necessary fulcrum of the myocardial muscle to complete its twisting movements. Keywords: heart; cardiac anatomy; myocardium; myocardial support; cardiac anatomy; myocardium; myocardial support