Oonobuyisa ohamba ne-atrium yangasekunene zii-superior vena cava kunye ne-inferior vena cava. Yomibini le mithambo izisa igazi elivela emzimbeni lisiya ngasekunene lentliziyo. Oonobuyisa abahamba nge-atrium yasengasekhohlo zibizwa ngokuba ngoonobuyisa abazii-pulmonary. Aba nobuyisa beza negazi elivela kwimiphunga eliya ngasekunene kwentliziyo.