Heart Anatomy

Question 1

What is the path taken around the heart by the right coronary artery?

Answer 1

• Originates from the right aortic sinus

- Travels between the right auricle and pulmonary trunk and through the coronary sulcus to the base of the heart

Question 2

What does the right coronary artery branch into and what parts of the heart do they supply?

Answer 2

Posterior interventricular coronary artery - right and left ventricles, posterior third interventricular septum

Right marginal coronary artery - right ventricle and the apex

Question 3

What is the path taken by the left coronary artery?

Answer 3

Travels between the left auricle and pulmonary trunk into the coronary sulcus

Question 4

What does the left coronary artery branch into and what parts of the heart do they supply?

Answer 4

Anterior interventricular coronary artery - Right and left ventricles, anterior 2/3 interventricular septum

Circumflex coronary artery - Left atrium and left ventricle

Left marginal coronary artery - Left ventricle

Question 5

What veins drain into the right atrium?

Answer 5

• Coronary sinus
• Superior vena cavae
• Inferior vena cavae

Question 6

Where is the coronary sinus situated? (The main draining vein of the heart)

Answer 6

Inferior to the left atrium

Question 7

What is the path taken by the great cardiac vein?

Answer 7

• Originates from the apex of the heart
• Travels along the anterior interventricular vein
• Turns left at coronary sulcus and goes into the coronary sinus

Question 8

What are the main branches of the aorta?

Answer 8

• Brachiocephalic
• Left carotid artery
• Left subclavian artery

Question 9

Outline the differences between the regions of the heart supplied by the right and left coronary arteries

Answer 9

Right - right atrium, SA and AV nodes, posterior part of interventricular septum

Left - left atrium, left ventricle, intraventricular septum, AV bundles

Question 10

What is the function of pacemaker cells and where are they found?

Answer 10

• Generate cardiac action potential

- Wall of right atrium

Question 11

Name the inflow valves of the heart chambers and state their locations

Answer 11

Mitral - between left atrium and left ventricle

Tricuspid - between right atrium and left ventricle

Question 12

Name the outflow valves of the heart chambers and state their locations

Answer 12

Aortic - between left ventricle and aorta

Pulmonary - between right ventricle and pulmonary artery

Question 13

How does the anterior surface of the right atrium differ from the posterior surface?

Answer 13

Smooth, thin posterior surface is derived from the right horn of sinus venosus

Rough, muscular anterior wall is composed of pectinate muscles and is derived from the primitive atrium

Question 14

What separates the two surfaces of the right atrium?

Answer 14

Crista terminals internally and sulcus terminalis externally

Question 15

Describe the structure of the left atrium

Answer 15

Large smooth walled part and smaller muscular auricle contacting pectinate muscles

Question 16

Where do the four pulmonary vein enter the left atrium?

Answer 16

Smooth posterior wall

Question 17

Describe the structure and function of the tricuspid valve

Answer 17

• Three cusps - anterior, posterior and septal
• Attached to anterior, posterior and septal papillary muscles via chordae tendinae
• Prevents black flow of blood into the right atria from the right ventricle during systole and guard the AV orifice

Question 18

How does the structure of the mitral valve differ from the tricuspid valve?

Answer 18

Consists of two cusps opposed to three - anterior and posterior

Question 19

Describe the structure of the semilunar valves

Answer 19

• Three cusps - right, left and posterior
• Edge of each cusp is thickened in the region of contact forming a lunule (bivalve)
• Free edge of the cusp is thickened further forming a nodule

Question 20

How do the semilunar valves differ from atrioventricular valves?

Answer 20

No tendinous cords to support them or papillary muscles

Question 21

What is the function of the chordae tendinae?

Answer 21

Prevent cusps of the tricuspid and mitral valves from prolapsing into the right atrium during systole