Which chamber of the heart has the thickest muscular walls?

The left ventricle has the thickest muscular walls among the heart's chambers due to its crucial role in systemic circulation. This chamber must generate a significant amount of pressure to pump oxygenated blood throughout the entire body, overcoming the resistance of the systemic vascular system. The muscular walls of the left ventricle are specially adapted to accomplish this, resulting in a thicker myocardium compared to the other heart chambers.

In contrast, the right ventricle has thinner walls because it only needs to pump blood to the lungs for oxygenation, which involves much less resistance than systemic circulation. The atria, including both the left and right atria, have even thinner walls since they primarily function as receiving chambers rather than as powerful pumps. This anatomical design ensures that the heart efficiently fulfills its role in circulating blood, highlighting the left ventricle’s specialization for high-pressure output.