What are the 4 walls of human heart?

There are actually four chambers of the human heart, not walls. They are: the right atrium, the left atrium, the right ventricle, and the left ventricle.

Right atrium: This chamber receives blood from the body through two large veins, the superior vena cava and the inferior vena cava. The superior vena cava brings blood from the head, arms, and chest, while the inferior vena cava brings blood from the abdomen and legs.

Left atrium: This chamber receives blood from the lungs through four pulmonary veins. The pulmonary veins carry oxygen-rich blood from the lungs to the heart.

Right ventricle: This chamber pumps blood to the lungs through the pulmonary artery. The pulmonary artery is a large artery that carries blood from the heart to the lungs.

Left ventricle: This chamber pumps blood to the rest of the body through the aorta. The aorta is the largest artery in the body and it carries oxygen-rich blood from the heart to the body's tissues and organs.