Anatomy of the Heart and Coronary Arteries

Question 1

What is the pericardium?

Answer 1

three-layered sac that surrounds the heart

Question 2

Describe the function of the pericardium

Answer 2

fix the heart in the mediastinum, limit motion, protect from infections, prevent excessive dilation and provide lubrication

Question 3

Name the three layers of the heart wall

Answer 3

Epicardium, myocardium, endocardium

Question 4

What is the epicardium?

Answer 4

the visceral layer of the serous pericardium

Question 5

What is the myocardium?

Answer 5

cardiac muscle (muscle fibres in bundles)

Question 6

What is the endocardium?

Answer 6

continuous with the endothelium

Question 7

Trace the flow of blood through the heart

Answer 7

superior vena cava and coronary sinus, right atrium through tricuspid valve, into the right ventricles and through pulmonary semilunar valve, into pulmonary trunk to the lungs (pulmonary artery), then returned to heart in four pulmonary veins into left atrium, blood passes through mitral valve into left ventricle, blood passes through aortic valve and out of aorta to the rest of the body

Question 8

Describe the internal structures within the right atrium

Answer 8

contains SAN (near SVC) and AVN (next to coronary sinus)

Question 9

Describe the internal structures within the left atrium

Answer 9

has pectinate muscle in auricle, smooth walls otherwise, and has the mitral valve and fossa ovalis

Question 10

Describe the internal structures within the right ventricle

Answer 10

contains the walls (trabecular carnae) including the moderator band, has a tricuspid valve held in place by chordae tendinae and papillary muscle

Question 11

Describe the internal structures within the left ventricle

Answer 11

contains trabeculae carnae, far thicker myocardium and aortic valve

Question 12

What is cristae terminalis?

Answer 12

smooth ridge in the wall of the right ventricle which has the SAN at the top

Question 13

What is the pectinate muscle?

Answer 13

meshwork-type muscle lining the atria

Question 14

What is the fossa ovalis?

Answer 14

remnants of foramen ovale which allowed passage of blood from one atria to the other in foetal development

Question 15

What is the ductus arteriosum?

Answer 15

present in a foetus and shunts blood from the pulmonary trunk to the aortic arch but this closes at birth to form the ligamentum arteriosum

Question 16

What is the moderator band?

Answer 16

branch of the conducting system carried by the trabecular carnae of the right ventricular wall

Question 17

What is the trabecular carnae?

Answer 17

walls of the ventricle with thick ridges

Question 18

Describe the path of the right coronary artery

Answer 18

On the anterior surface it splits into the right marginal artery which goes towards the heart apex, and posteriorly the right coronary artery continues and produces the posterior descending artery

Question 19

Describe the path of the left coronary artery

Answer 19

quickly branches into the left circumflex and the left anterior descending (interventricular) artery. There is a diagonal branch from the LAD. The left circumflex artery travels round the heart in the coronary sulcus and also gives off a branch known as the marginal vein which travels to the apex of the heart

Question 20

Describe the main coronary veins

Answer 20

superior vena cava, inferior vena cava and coronary sinus