Regions of the cardiac tube

• looping, remodeling, lengthening and realignment will transform the primitive heart tube into four primodial heart chambers
• The primordial heart chambers are: the sninus venosus, primitive atrium, primitive ventricle and bulbus cordis
• The sinus venosus will become part of the right atrium and the superior vena cava
• The primitive atrium will form (most of the) right atrium and the entire left atrium.
• The primitive ventricle will shape the definitive left ventricle
• the bulbus cordis will form a large part of the right ventricle
• The outflow end of the primitive heart, cranial to the bulbus cordis, will subdivide into the conus arteriosus
• The conus arteriosus will become incorporated into the ventricles, and the truncus arteriosus
• The truncus arteriosus will become the ascending aorta and pulmonary artery
• Function of cardiac looping → brining the chambers of the mature heart into their correct shape / ralation
• The bulbus cordus moves → caudally and ventrally to the right

  The primitive atrium moves → dorsally and cranially

  The outflow tract come to lie → between the atria

  The sinus venosus moves → crainially