Thorax II: 3.13 & 4.1

3.13. List the embryological origins of the important structures of the heart.
3.13.1. smooth part of right atrium and the "valve" of the SVC, SA node.
Sinus venosus (right horn)
3.13.2. coronary sinus and its valve

Sinus venosus (left horn)
3.13.3. crista terminalis

Valve of sinus venosus (right)
3.13.4. parts of atrial septum including the left side

Valve of sinus venosus (left)
3.13.5. rough part of right and left atria and the auricles

Common atrium
3.13.6. left atrial wall

Septum primum
3.13.7. Right side of the atrial septum

Septum secumdum
3.13.8. Fossa ovalis

Foramen ovale
3.13.9. parts of the atrioventricular wall, mitral, and tricuspid valves

Endocardial cushions
3.13.10. membraneous part of ventricular septum, part of arterial trunk

Endocardial cushions
3.13.11. trabeculated part of R ventricle and aortic vestibule of L ventricle

Bulbus cordis
3.13.12. ascending (ventral) aorta and pulmonary artery

Truncus arteriosus
3.13.13. parts of the right and left ventricle

Common ventricle

4. Vessels
4.1. Identify the left coronary artery.
4.1.1. Locate its origin in the aortic sinus
4.1.2. Identify its major branches. What cardiac areas do they supply?

• Sinuatrial nodal – left atrium and sinuatrial node
• Anterior interventricular – right and left ventricles and anterior two thirds of interventricular septum
• Circumflex – left atrium and left ventricle
• Left marginal – left ventricle
• Posterior interventricular – right and left ventricles and posterior two thirds of interventricular septum