Myocardial support

<p><strong>Objective: </strong>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.</p><p><strong>Material and methods: </strong>We used: 1) cardiac dissection in ten young bovine hearts [800-1000 g]; 2) cardiac dissection in eight human hearts: one embryo of 23 weeks gestation; one 10 year old, 250 g; and six adults, mean weight 300 g. 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. <strong>Results: </strong>In anatomical investigations we have found in all human and bovine hearts studied a nucleus underlying the right trigone of bone-chondroid-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. <strong>Conclusions:</strong> 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.</p>