Is the last stop the blood makes before leaving the heart is the left atrium?

yes, it does pass because when the de oxygenated blood comes through the left atrium the through the valves then into the left ventricle and goes to the lungs the it gets oxygenated but the de oxygenated blood goes through the veins and the oxygenated blood goes through the arteries and the capillaries join the both back to the process when it goes to the lung it gets oxygenated and the it goes back into the right atrium after that through the other valves the into the right ventricle then it goes through a big pipe called the AYOTA that is the process of the heart.