Which layer lies directly on the surface of the heart?

Which layer lies directly on the surface of the heart?

• A. Epicardium
• B. Endocardium
• C. Myocardium
• D. Pericardium

Answer: (A)

The layer that directly covers the heart is the epicardium, which is the visceral layer of the serous pericardium. It hugs the heart’s surface and contains the coronary vessels on the heart itself. Beneath it lies the myocardium, the thick muscular wall that contracts to pump blood, and inside the heart chambers is the endocardium, a smooth lining. The pericardium as a whole sits outside the epicardium, consisting of a fibrous outer layer and a serous inner layer that splits into parietal (lining the sac) and visceral (the epicardium) portions, with a small pericardial cavity in between containing lubricating fluid.

The layer that directly covers the heart is the epicardium, which is the visceral layer of the serous pericardium. It hugs the heart’s surface and contains the coronary vessels on the heart itself. Beneath it lies the myocardium, the thick muscular wall that contracts to pump blood, and inside the heart chambers is the endocardium, a smooth lining. The pericardium as a whole sits outside the epicardium, consisting of a fibrous outer layer and a serous inner layer that splits into parietal (lining the sac) and visceral (the epicardium) portions, with a small pericardial cavity in between containing lubricating fluid.