The Difference between the Left and Right Ventricles
The demand for blood between the left and right atrium are the same. However, the demand is different for the left ventricle and right ventricle. The two also have different structural differences
The lungs are closer to the heart and the pulmonary blood vessels are relatively short and wide. For these reasons, the right ventricle normally does not need to work as hard. Also, the muscle walls of the right ventricle are relatively thin. When the right ventricle contracts, it squeezes the blood very efficiently with minimal effort, but it develops low pressure.
A comparable pumping arrangement will not work as well for the left ventricle. Four to six times as much pressure must be exerted around the systemic circuit as around the pulmonary circuit. The left ventricle has an extremely thick muscular wall and is round in cross section. When the left ventricle contracts, it shortens and narrows. This effect is similar to squeezing a toothpaste.
Photo Credit: Mayo Clinic