The right atrium receives systemic venous blood from the superior vena cava, which drains the upper portion of the body, and from the inferior vena cava, which drains the lower portion.

• 右心房通过上腔静脉和下腔静脉接受全身静脉血，上腔静脉流的是身体上半部分的血，下腔静脉，流的是身体下半部分的血。