The left ventricular wall of the heart is thicker than the right wall in order to generate higher pressure to pump oxygenated blood throughout the body.

Explanation:
The left ventricle receives oxygenated blood from the lungs and pumps it out through the aorta to the rest of the body.

Because the aorta is a large artery that supplies blood to the entire body, the left ventricle has to generate a higher pressure to overcome the resistance of systemic circulation.

Therefore, the left ventricular wall is thicker and stronger than the right one.

The right ventricle pumps blood only to the lungs for oxygenation wherein the resistance is lower, thus it is not as thick as the left ventricle.