Anatomy & Physiology

Question 1

What are the three layers of the pericardium?

Answer 1

Although most echo textbooks only refer to TWO layers of the pericardium there are three anatomic layers.

The serous visceral (covering the outer surface of the heart, the epicardium), the serous parietal which lines the inside of the fibrous pericardium (the parietal or thick outer sack).

Question 2

What is the normal flow velocity through the pulmonic valve, as assessed by Doppler ultrasound in both adults and children?

Answer 2

The normal pulmonic valve gradient is 1 to 3 mmHg.

• In adults, the normal pulmonic flow velocity is a mean of 0.7 m/sec, with a range of 0.5 to 0.9 m/sec.
• In children, the normal mean pulmonic flow velocity is slightly higher, at 0.8 m/sec.

Question 3

What is the function of the pericardium?

Answer 3

Because surgical removal of the pericardium may not produce any ill effects, the exact function of the pericardium is unclear.

In general, the pericardium limits ventricular filling, reduces the friction that results from cardiac motion and may act a barrier to infectious organisms.

Question 4

Describe the anatomy of the pulmonic valve, including the name and location of each leaflet.

Answer 4

The pulmonic valve is the most anteriorly positioned cardiac valve.

It lies within the right ventricular outflow tract, to the left of the aortic valve.

The pulmonic valve has three leaflets: the anterior, right (posterior), and left.

The right leaflet is also referred to in M-mode books as the posterior.

Question 5

What is the name of the valve of the coronary sinus?

Answer 5

The valve of the coronary sinus is the Thebesian valve.

Question 6

In which chamber would you see a chiari network?

Answer 6

Chiari network’s are seen in the right atrium as fine strands of tissue similar to chordea of the mitral and tricuspid valves.

Question 7

When is the left ventricular volume the largest?

Answer 7

The left ventricular volume is largest at end diastole (when we measure it).

Question 8

When is the left atrium volume the largest?

Answer 8

The left atrium volume is largest at end systole.

Question 9

How many scallops is the mitral valve divided into and what are their names?

Answer 9

The mitral valve is divided into 6 scallops (segments).

Anterior 1, 2 & 3 and Posterior 1, 2 & 3

Question 10

In the parasternal short-axis view, at the level of the mitral valve and papillary muscle, how many segments is the left ventricle divided into?

Answer 10

In the parasternal short-axis view, at the level of the mitral valve (Basal) and papillary muscle (Mid-Cavity), the left ventricle is divided into six segments (based on the ASE 17 segment model).

Question 11

Name the ventricular segments seen in the parasternal short-axis view.

Answer 11

The ventricular segments are the: inferolateral (1), anterolateral (2, anterior (3), anteroseptal (4), inferoseptal (5), inferior (6)

Question 12

In the apical four-chamber view, which two walls of the left ventricle are seen?

Answer 12

In the apical four-chamber view, the inferoseptal and anterolateral walls of the left ventricle are seen.

Question 13

In the apical two-chamber view, which two walls of the left ventricle are seen?

Answer 13

In the apical two-chamber view, the anterior and inferior walls of the left ventricle are seen.

Question 14

Which walls of the left ventricle are seen in the parasternal and apical long-axis views?

Answer 14

The anteroseptal and inferolateral walls of the left ventricle are seen in the parasternal and apical long-axis views.

Question 15

Which two aortic valve leaflets are seen in the parasternal and apical long-axis views?

Answer 15

The right and noncoronary leaflets are seen in these views. The right leaflet is on top (superior) and the noncoronary is on the bottom (inferior).

Question 16

Where is the coronary sinus located in the parasternal long-axis view (PLAX)?

Answer 16

The coronary sinus lies in the posterior atrioventricular (AV) groove. This groove is located between the left atrial and the left ventricular walls and lies posterior to the mitral valve. In the parasternal long-axis view, the coronary sinus can sometimes be seen as a small echo-free circle.

Question 17

In the PLAX where is the coronary sinus located in relation to the descending aorta?

Answer 17

The coronary sinus is located anterior to the descending aorta. If the coronary sinus is dilated, it may be mistaken for the descending aorta.

Question 18

Name the three major coronary arteries.

Answer 18

The three major coronary arteries are the right, left anterior descending (LAD), and circumflex arteries. The latter two arteries branch from the left main coronary artery, [which is not considered a major artery because it is very short].

Question 19

Where are the coronary arteries located on the surface of the heart?

Answer 19

The coronary arteries are located on the outer, epicardial surface of the heart as follows:

• The right coronary artery (RCA) arises from the right aortic-root sinus, follows the right atrioventricular junction, and descends along the posterior interventricular groove.
• The left anterior descending coronary artery (LAD) follows the anterior interventricular groove.the circumflex coronary artery (Circ) courses along the left atrioventricular junction.

Question 20

Name the cardiac walls supplied by the Right coronary artery.

Answer 20

Normally, the major coronary arteries supply the cardiac walls as follows (based on the ASE 17 segment model):

Right coronary artery

• a) inferior wall
• b) inferoseptal
• c) right ventricular apex
• c) right ventricular free wall

Question 21

Name the cardiac walls supplied by the left anterior descending artery.

Answer 21

Normally, the major coronary arteries supply the cardiac walls as follows (based on the ASE 17 segment model):

Left anterior descending artery

• a) anterior wall
• b) anteroseptal
• c) left ventricular apex

Question 22

Name the cardiac walls supplied by the circumflex artery.

Answer 22

Normally, the major coronary arteries supply the cardiac walls as follows (based on the ASE 17 segment model):

Circumflex artery

• a) anterolateral wall
• b) inferolateral wall

Question 23

Describe the normal mitral valve anatomy.

Answer 23

• The mitral valve is a bileaflet valve situated between the left atrium and the left ventricle. The valve’s anterior leaflet is relatively long, lies close to the aorta, and comprises less of the valve’s circumference than the posterior leaflet.
• The posterior leaflet is shorter, takes up more of the circumference and is usually divided into three sections (scallops).
• Both the anterior and the posterior leaflets are attached to the ventricular papillary muscles by multiple chordae tendineae.

Question 24

What causes an opening snap (mitral)?

Answer 24

An opening mitral snap occurs shortly after the second heart sound (which signifies aortic and pulmonic closure). The snap is caused by the abrupt cessation of leaflet opening when the mitral valve is tethered.

Question 25

What is diastasis?

Answer 25

Diastasis denotes the middle portion of diastole, which occurs between early, rapid filling of the ventricles and the start of atrial contraction. The duration of diastasis varies with the heart rate.

• Diastasis is quite long in patients with bradycardia and quite short in those with tachycardia.

Question 26

How much of ventricular filling occurs during the passive phase of diastole?

Answer 26

At normal pressures, approximately 70% of ventricular filling occurs during the passive phase of diastole; atrial contraction accounts for the remaining 30% of ventricular filling. Of course, these percentages will change in patients with valvular abnormalities such as mitral stenosis or ventricular compliance problems such as hypertrophic cardiomyopathy.

Question 27

Name the four phases of diastole.

Answer 27

The four phases of Diastole are:

• Isovolumic relaxation time (closure of AV to opening of the MV)
• Early filling (passive)
• Diastasis
• Atrial contraction (active)

Question 28

How does respiration affect venous return?

Answer 28

Inspiration will cause an overall increase in venous (right sided) return. Expiration will cause a decrease in venous return.

Question 29

What is the normal flow velocity (mean value and range) through the mitral valve, as documented by Doppler imaging in adults and children?

Answer 29

As documented by Doppler imaging, the normal flow velocity through the mitral valve in adults is a mean of 0.9 m/sec, with a range of 0.6 to 1.4 m/sec.

• In children, the flow velocity is slightly higher, having a mean of 1.0 m/sec and a range of 0.7 to 1.4 m/sec.

Question 30

What is the normal mitral valve area?

Answer 30

The normal mitral valve measures 4 to 5 cm² in area and is therefore smaller than the tricuspid valve.

Question 31

Describe the normal aortic valve anatomy?

Answer 31

The aortic valve is comprised of three cup-shaped leaflets: the right, left, and noncoronary leaflets. Behind each leaflet, the aortic wall dilates to form a sinus of Valsalva. The left and right coronary arteries
originate from the sinuses of the left and right aortic valve leaflets, respectively.

Question 32

Why is the aortic valve so resistant to regurgitation?

Answer 32

Compared to the mitral leaflets, the aortic leaflets are unsupported. Nevertheless, they are partly surrounded by the heart’s fibrous skeleton, which strengthens the aortic annulus. Because the leaflets are cup-shaped and their edges overlap (supporting each other), the normal aortic valve is very resistant to regurgitation.

Question 33

Name the branches of the aortic arch starting with the one closest to the aortic valve.

Answer 33

Starting at the top of the transverse arch closest to the aorta is the innominate (right brachiocephalic artery), then the left common carotidand finally the left subclavian artery.

Question 34

Describe the anatomy of the tricuspid valve, including the name and location of each leaflet

Answer 34

The tricuspid valve is located between the right atrium and the right ventricle.

It has three leaflets: the anterior, posterior, and medial (or septal) leaflets.

These names reflect the leaflets’ anatomic relationships to the right ventricle. The medial (septal) leaflet is connected to the septal wall. Its insertion is located closer to the cardiac apex than that of the anterior mitral leaflet.