I believe it's the right and left brachiocephalic veins
Superior vena cava.
After the flow of blood(oxygenated) through the brachiocephalic(jugular) artery, the brachiocephalic (jugular) vein will return the blood(de-oxygenated) back to the anterior part of the vena cava. Then, into the right auricle. Et-cetera.
Brachiocephalic
The brachiocephalic artery is a branch off of the aortic arch and send blood to the head, neck, and right arm.
the intercostal verins drains into the brachiocephalic.
The brachiocephalic artery divides into the right common carotid artery and the right subclavian artery.
To transport de-oxygenated blood to the lungs.
Blood goes from the vena cava into the right atrium of the heart
It is an artery of the mediastinum that supplies oxygenated blood the right arm, head and neck.
The blood travels through the digital veins, the superficial palmar veins which drain into the cephalic vein, the median cubital vein, the basilic vein, the axillary vein, the subclavian vein, the brachiocephalic vein, and the superior vena cava to go to the right atrium.
Brachiocephalic Trunk,Left common Carotid artery,left subclavian artery