Structure of the heart (Mon 16th)

Question 1

Basics of the heart?

Answer 1

1. The right side of the heart receives deoxygenated blood from the body through the vena cava.
2. It pumps blood to the lungs through the pulmonary artery to pick up oxygen.
3. The left side of the heart receives the oxygen-rich blood through the pulmonary vein from the lungs.
4. The left side pumps it to the body using the aorta.

Question 2

What is the difference between the superior and inferior vena cava?

Answer 2

1. The inferior vena cava carries deoxygenated blood from the lower half of the body to the right atrium of the heart.
2. The corresponding vein that carries deoxygenated blood from the upper half of the body is the superior vena cava.

Question 3

What is the pulmonary trunk?

Answer 3

The pulmonary trunk is a major vessel of the human heart that originates from the right ventricle. It branches into the right and left pulmonary arteries, which lead to the lungs… In the lungs, the blood becomes purified and oxygenated again.

Question 4

What is pericardium?

Answer 4

1. The pericardium are the membranes that surround the heart.
2. It is made of two layers:
   
   • The fibrous layer is the tough outer layer. At the bottom it is connected to the central tendon of the diaphragm and at the top it is continuous with the adventitia/outer layer of the great vessels.
   • The serous layer is a double layer folded into itself like pleura membranes (think squished ballon). The inner layer is called the visceral layer and is on the surface of the heart. This layer folds over when it hits any vessels and then becomes the parietal layer. The parietal layer is also directly attatched to the back of the fibrous layer.
   • The space inside the serous and parietal membranes is called the pericardial cavity, and is filled with pericardial fluid.

Question 5

What is cardiac tamponade?

Answer 5

Fluid in pericardial cavity, harder to pump blood.

Question 6

What is pericarditis?

Answer 6

Inflammation of the pericardium (fibrous/serous)

Question 7

What is a reflection?

Answer 7

The folding of a membrane from the wall of a cavity over an organ and back to the wall.

Question 8

What are pericardial sinuses?

Answer 8

• These are blind-ended (closed at one end) spaces where the visceral layer of serous pericardium reflects, forming a space.
• Remember that the pariatel membrane is the glistenig back of the rough fibrous membrane.
• There is the transverse sinus, in this blind ended space you can fit your finger. It seperates the arteries (above your finger) from the pulmonary veins (below your finger).
• There is the oblique sinus, which is formed when the visceral layer reflected under the pulmonary veins, and this created a bind ended space.

Question 9

LO’s

Answer 9

1. Describe the relationship of the heart to the pericardial sac
2. Describe and identify the gross anatomy of the heart and the position of the four chambers
3. Describe the gross anatomical organisation of the cardiovascular system

Question 10

How does the heart sit in situ? So if somone is stood infront of you, and their heart was exposed what would you see?

Answer 10

1. The heart is twisted so it doesn’t sit flat, but to the side so you see more of the RA and RV.
2. I see the aortic arch closer to me than the pulmonary trunk.
3. The left atrium is more to the back of the heart.

Question 11

What is the apex of the heart?

Answer 11

1. The apex of the heart is it’s tip
2. It is formed by the left ventricle
3. It is essentially the most inferior (AKA bottom) portion of the heart.
4. The apex is directed, downwards, forwards and to the left.
5. It can be found in the fifth intercostal space if you go down from the middle of your clavicle.

Question 12

What are the three surfaces of the heart? Think of it as a pyramid (the base of the pyramid is at the back).

• Sterocostal = front
• Base = back
• Diaphragmatic= bottom

Answer 12

1. Sternocostal/ Anterior: This is the front of the heart. It is formed mainly by the right atrium and right ventricle. Most of it is covered by the lungs infront, except for the part uncovered due to the cardiac notch.
2. Diaphragmatic/ Inferior: This is what the heart sits on, the central tendon of the diaphragm. It is formed mainly by the right and left ventricles.
3. Base/ Posterior: This is the back of the heart, even though its called the base. It is formed mainly by the left atrium. It shows openings of the four pulmonary veins.

Question 13

What are the borders of the heart?

Answer 13

When looking at the heart from the front, whats on the top, bottom, rght and left border?

1. Superior: Aortic Arch, Pumonary Trunk and the two atria
2. Right: The RA
3. Left: LV and a bit of the LA
4. Inferior: RV and part of the apex.

Question 14

In the anterior view of the heart what can you see?

Answer 14

1. The right auricle
2. The right ventricle
3. The apex
4. The left auricle very slightly
5. The superior and inferior vena cava draining into the RA
6. The aortic arch
7. The pulmonary trunk

Question 15

What are auricles?

Answer 15

• One auricle is attached to each of the anterior surfaces of the outer-walls of the atria.
• They are wrinkled pouch-like structures.
• Their purpose is to increase the capacity of the atrium, and so also increase the volume of blood that it is able to contain.

Question 16

In the posterior view of the heart what can you see? Remember for posterior view, your right and left is the same as their right and left.

Answer 16

1. The left ventricle
2. The left atrium, and some of the right atrium
3. The 4 pumonary veins
4. The right and left pulmonary artery
5. The aortic arch
6. The superior and inferior vena cava