Heart musculature, myocardium
Frontal view of the human heart, its layer of musculature (myocardium). On the top left, the right atrium is visible, below it the right ventricle. On the bottom right, parts of the left ventricle are seen. On the left side, the inferior and superior venae cavae lead vertically into the right atrium. On the top left, the right pulmonary veins are seen, and on the right, the left pulmonary veins. In the middle it shows the semilunar valve of the pulmonary artery (blue) and the aorta (red).
