EM 371 Heart

Left Ventricle

Scanning electron microscopy (SEM) of the left ventricle of the heart. The left ventricle is the heart's main pumping chamber. It possesses thick, muscular walls to generate the high pressure necessary to propel oxygenated blood into the systemic circulation.

Trabeculae Carneae

The inner surface of the ventricle (tan) is covered by irregular muscular columns called trabeculae carneae (orange). Some project outward like bridges, while others are attached along their entire length to the wall.

They are composed of cardiac muscle and are covered by the endocardium.

Functional Significance

• Pumping Efficiency: Expand the functional surface area of the internal wall, allowing the ventricle to contract with a more powerful, wringing motion
• Increased Surface Area: Irregular surface ensures the walls do not stick together during contraction (systole), allowing for a rapid and efficient refill during relaxation (diastole)
• Tension Management: Add structural integrity to the wall, maintaining flexibility while resisting the high internal pressures of the left ventricle