Anatomy · Embryology and Genetics

Development of heart and congenital heart defects

7 min read

  • Heart develops from a single primitive heart tube (mesodermal), formed from paired cardiogenic cords in the cardiogenic area.
  • It is the first organ to function, beginning to beat at the end of the 3rd week IUL.

Formation of Heart Tube and Its Subdivisions

Sequence

  • Cardiogenic cords → heart tube → five dilatations → cardiac looping → S-shaped heart → septa → chambers
  • Heart tube forms by canalization and craniocaudal fusion of paired cardiogenic cords in the 3rd week IUL; unfused caudal ends become the sinus venosus horns.

Fate of the five heart-tube dilatations