**Cardiac Surgery**

**Chapter 9**

**The Basis of Management of Congenital Heart Disease**

By the 3rd week of development the heart has developed from the cardiogenic region, a horseshoe-shaped structure, at the cranial end of the embryo, when it is about the size of a raisin. By day 21 the primitive heart tube has moved below the head region and by day 22 it fuses and moves into the future thoracic cavity and it is from this time that it begins to beat. The tube now starts to bend and twist and over the next 8 days, various chamber of the heart begin to develop and by the end of 2 months it bears a superficial resemblance to the fetal

The tube is anchored at one end by the arterial trunks and at the other end, by the various venous channels draining into it. Being fixed at both ends, the cardiac tube grows rapidly in length and begins to twist and bend. The embryonic ventricle is bent in to a loop to the right of the midline and the ventricle grows rapidly to cover the atrium and the great veins (figure 1). The sacculations projecting laterally will become the right atrium and the left atrium. The future left ventricle lies to the left of interventricular groove and the right ventricle or the bulboconus region communicates with the truncus arteriosus. A four chambered structure is formed from this convoluted tube by development of 3 septa which partitions the atria,

The septae develop simultaneously at about the same time between the 28 to 42nd day. The atria and ventricle are separated by a deep groove, the atrio-ventricular groove which appears like an invagination from inside.This forms the atrio-ventricular canal, which becomes divided

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© 2013 Subramaniam and Solomon; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

Krishnan Ganapathy Subramaniam and

Additional information is available at the end of the chapter

**1.1. Cardiac embryology — The development of the heart**

*1.1.1. Early heart development and the folding of the primitive tube*

Neville Solomon

**1. Introduction**

heart. [1]

http://dx.doi.org/10.5772/53654

ventricle and the truncus arteriosus. [2]

properly cited.
