Why does the left ventricle have a thick wall?

The left ventricle has a thick wall primarily to pump blood further throughout the body. This chamber is responsible for circulating oxygenated blood to various tissues and organs, which are located at significant distances from the heart. To achieve this, the left ventricle must generate a substantial amount of pressure during each contraction. A thicker wall allows for stronger contractions and thus an increased ability to propel blood through the aorta and into the systemic circulation.

This requirement for strength and pressure is why the muscular layer of the left ventricle, known as the myocardium, is much thicker than that of other heart chambers, like the right ventricle, which only needs to pump blood a short distance to the lungs. So, the thickness of the left ventricle is directly related to its function of delivering blood effectively throughout the body.