The Heart

Question 1

List the layers of the Pericardium from internal to external

Answer 1

• visceral pericardium (epicardium)
• pericardial cavity
• parietal pericardium
• fibrous pericardium
• pericardial mediastinal pleura

Question 2

Describe the position/orientation of the heart inside the thorax

Answer 2

• spans intercostal spaces 3-6
• the base is directed craniodorsally
• the apex is directed caudoventrally and toward the left
• auricular surface faces the left
• atrial surface faces the right

Question 3

What does the pulmonary circuit consist of?

Answer 3

right ventricle > pulmonary arteries > lungs > pulmonary veins > left atrium

Question 4

What does the systemic circuit consist of?

Answer 4

left ventricle > aorta > body > vena cava > right atrium

Question 5

Describe the internal feature of the Right Atrium and Auricle

Answer 5

• a main sinus part and a blind pouch (auricle)
• intervenous tubercle diverts blood, and is cranial to the fossa ovalis
• crista terminalis is a dorsal ridge that separates the sinus and auricle
• pectinate muscles in the auricle

Question 6

Describe the internal features of the Right Ventricle

Answer 6

• AV valve with parietal and septal cusps
• papillary muscles with chordae tendinae extending from the cusps
• trabeculae septomarginalis: muscular strand extends across ventricle
• trabeculae carneae: myocardial ridges on inner wall
• conus arteriosus: funnel shaped portion extending toward pulmonary trunk
• pulmonary semilunar valve

Question 7

Describe the grooves of the heart

Answer 7

• coronary groove: encircles base of the heart between atria and ventricles, contains coronary vessels
• paraconal interventricular groove: on auricular surface, contains paraconal interventricular branch of left coronary a., and great cardiac vein
• subsinuosal interventricular groove: on atrial surface, contains circumflex branch of left coronary a.

Question 8

What is the fibrous skeleton?

Answer 8

• a CT layer that separates the atria and ventricles
• delays ventricular contraction
• atrial myocardial cell bundles anchored to upper margin
• ventricular myocardial cell bundles anchored to lower margin

Question 9

What is the foramen ovale?

Answer 9

• opening in the fetal heart that allows blood to pass between atria
• closes after birth and becomes the fossa ovale

Question 10

What is the ductus arteriosus?

Answer 10

• shunts blood from pulmonary artery to the aorta in the fetal heart to bypass the lungs
• fibrous remnant in adult is called ligamentum arteriosum

Question 11

Describe Persistent Right Aortic Arch

Answer 11

• the right arch develops instead of the left
• esophagus is between the arch and ligamentum arteriosum
• ligamentum arteriosum constricts the esophagus causing mega-esophagus and regurgitation of solid food

Question 12

What areas coincide with PAM and T?

Answer 12

P: pulmonary valve, 3rd intercostal space, just above sternal border
A: aortic valve, 4th intercostal space, just above costochondral junction
M: left AV valve, 5th intercostal space, at costochondral junction
T: right AV valve, 4th intercostal space, near costochondral junction

Question 13

Describe the nutritive blood supply to the heart

Answer 13

• coronary arteries deliver oxygenated blood to the heart tissues
• great cardiac vein returns blood supplied to heart by the left coronary artery