First let me start by saying that the are 2 vena cava's the superior and the inferior. the inferior vena cava carries deoxygenated blood from the bodies lower half to the hearts right atrium and the superior vena cava carries deoxygenated blood from the bodies upper half to the hearts right atrium.
Chat with our AI personalities
The veins are connected to the heart and the blood simply runs through them to the heart and the the arteries are connected to the heart also but the blood runs through the arteries in the opposite direction, the arteries carry the blood from the heart to everywhere round the body.
Arteries carry blood from the heart to everywhere in your body. Veins return the blood to your heart - except for the hepatic portal vein which carries blood form the stomach to the liver.
Right side of the heart which then pumps through the lungs.
Veins carry blood to the heart.