Surgery | Basic Science | Development Embryology of Heart and Great Vessels

Developmental Embryology of Heart and Great Vessels
Session Overview
Description
The key events that occur in the development of the heart and the great vessels.

Learning Objectives
By the end of this session you will be able to:

• Define the key events that occur as the heart develops from a primitive heart tube to a four chambered system in order to explain some common anomalies of the heart and great vessels
• Establish the sequence of events that occur during partitioning of the primitive atrium and ventricle; the formation of the cardiac valves; the transformation of the outflow tract from a single to a double tube
• Summarise the development of the aortic arches and their derivatives

The heart starts at around 18 days as a simple myocardial tube that subsequently loops and rotates. As it does so, sheets and cushions of cardiac mesenchyme progressively subdivide the lumen of the tube into right and left sides, each with an atrium and ventricle and with their own inflow and outflow channels.

Partitioning of the chambers, septation of outflow tracts and remodelling and subsequent perinatal changes in the peripheral vasculature are all complex processes: this may account for the relatively high proportion of birth defects associated with the heart and cardiovascular system. Molecular regulation of the processes remains largely obscure. This session will take you through the key stages that occur during the development of the heart, from the formation of two primitive endocardial tubes to a fully differentiated heart.