Which chamber of the heart has the thickest myocardium?

The left ventricle has the thickest myocardium because it is responsible for pumping oxygenated blood throughout the entire body, which requires generating a significant amount of pressure. The left ventricle must contract forcefully to overcome the high resistance of the systemic circulation. As a result, its muscle wall, or myocardium, is much thicker than that of the other heart chambers, enabling it to accomplish this demanding task effectively.

In contrast, the right ventricle pumps blood to the lungs, where the resistance is lower, so its myocardial wall is thinner. The atria, both left and right, also have thinner walls since they primarily serve as receiving chambers for blood returning to the heart, with less pressure exerted on them compared to the ventricles. This anatomical structure is crucial for the heart’s efficiency and functionality in the circulatory system.