Heart

Question 1

What is the pericardium?

Answer 1

fibrous sac surrounding the heart and the roots of the great vessels

Question 2

What are the three layers (from outer to inner) of the pericardium?

Answer 2

A. Fibrous Pericardium-tough connective tissue outer layer
B. Serous Pericardium
-1. Parietal Layer: lines the surface of the fibrous layer
-2. Visceral Layer: lines the heart

Question 3

Between which two layers is the pericardial fluid located?

Answer 3

Between the parietal and visceral pericardium layers of the heart

Question 4

Describe the pericardial innervation

Answer 4

Phrenic N.:

• roots are C3, C4, C5 (3-4-5 keeps you alive)
• innervates the fibrous and serous parietal pericardium and then continues on to innervate the diaphragm

Vagus N:

• innervates the visceral parietal pericardium
• function is to provide parasympathetic innervation to these regions

Question 5

What is referred pain? Describe the referred pain of the pericardium.

Answer 5

Referred pain is the phenomena when pain from an organ is carried by somatic afferent fibers in the sensory nerves. The pain is felt outside/away from original source of the pain on the corresponding dermatome.

The referred pain of the pericardium is the dermatomes for the C3, C4, C5 region, which is the supraclavicular region of the shoulder and the lateral neck

Question 6

What is a dermatome?

Answer 6

The bilateral region of skin innervated by a pair of spinal nerves, and it provides sensory afferents

Question 7

What is pericarditis? Causes? Presentation?

Answer 7

Pericarditis is inflammation of the pericardium. It is caused by viral/bacterial infections, systemic illness, and post-myocardial infarction. With pericarditis, the patient usually gets sharp chest pains that can radiate to the neck, arms, and left shoulder, and it worsens with inspiration/cough

Question 8

How would you clinically differentiate between a myocardial infarction and pericarditis?

Answer 8

Since the symptoms are similar (chest pains that radiate to the neck, arms, and left shoulder), I would see if the patient gets relief of the pain by sitting forward. This would indicate pericarditis, because pericarditis is relieved by sitting forward.

Question 9

What is a pericardial effusion? Causes? Treatment?

Answer 9

Pericardial effusion is accumulation of excess fluid in the pericardial sac. It is a problem because the amount of fluid that should be in the pericardial sac is relatively fixed, so an excess amount of fluid within the pericardial sac compresses the heart, decreases heart contractility and function, and can lead to biventricular failure. Treatment of pericardial effusion is usually via removal of the fluid with a needle.

Question 10

Explain the flow of blood through the heart (general)

Answer 10

SVC, IVC, CS –> Right Atrium (tricupsid valve) –> Right ventricle (pulmonary valve) –> Pulmonary Trunk –> Lungs (pulmonary veins) –> Left Atrium (mitral/bicupsid valve) –> Left Ventricle (aortic valve) –> Aorta (and also the coronary arteries to the heart) –> Body

Question 11

Explain which artery/vein carries oxygenated/deoxygenated blood in the heart

Answer 11

SVC, IVC, and CS: deoxygenated blood
Pulmonary Trunk/Artery: deoxygenated blood
Pulmonary Vein: oxygenated blood
Aorta/Coronary Artery: oxygenated blood

Question 12

Clinical Signficance of a patent ductus arteriorsus and patent foramen ovale.

Answer 12

Patent ductus arteriosus: opening between the pulmonary trunk and the aorta. Typically after birth turns into the ligamentum arteriosum.

Patent Foramen ovale: opening between the right/left atria. Typically after birth it turns into the fossa ovalis.

This is clinically significant because it is supposed to close after birth, in the event where it does not close, you get mixing of the oxygenated and deoxygenated blood, which is not ideal

Question 13

Purpose of the papillary muscles and the chordae tendinae

Answer 13

the papillary muscles contract to hold the chordae tendinae, which hold the tricupsid/bicupsid valves, during ventricular systole (contraction). This prevents backflow/regurgitation of blood into the aorta

Question 14

Describe the branching of the aortic arch

Answer 14

Ascending aorta –> brachiocephalic trunk –> Left Common carotid artery –> left subclavian artery

Brachiocephalic trunk then branches into the right subclavian artery and the right common carotid artery

Question 15

Describe which vesicles drain into and leave each atrium/vesicle

Answer 15

Right Atrium:
-In: SVC, IVC, CS

Right Ventricle:
-Out: Pulmonary Trunk (LPA, RPA)

Left Atrium
-In: Pulmonary Veins (4 Branches)

Left Ventricle:
-Out: Aorta/coronary arteries

Question 16

What are the three layers of the heart wall? (outermost–> innermost)

Answer 16

1. Epicardium: visceral layer
2. Myocardium: muscle layer
3. Endocardium: inner endothelial lining/covering of the trabeculae

Question 17

List which muscles are in which chamber of the heart and correlate with its function

Answer 17

Right Atrium: pectinate muscles (roots are the cristae terminalis (interior) and succulus terminalis (exterior)
Right/Left Ventricle: papillary muscles (right x3, left x2) and trabeculae carnae
Left Atrium: very few pectinate muscles by the left auricle

Question 18

Look at a picture of a heart, and identify all of the structures of the ventricles and atria.

Answer 18

Did you identify the sinus venarum, cristae terminalis, succulus terminalis, intratrial septum, fossa ovalis, moderator band. I think not. Do it again.

Question 19

Describe the Atrioventricular valves

Answer 19

Connect the atrium to the ventricle
Fish mouth
Chordae tendinae and papillary muscles
Tricupsid and mitral valve

Question 20

Describe Semilunar valves

Answer 20

look like moons
three cups
pulmonary and aortic
pulmonary is most anterior

Question 21

Describe the valve diseases, the types, causes, and treatment

Answer 21

Valve Disease Types

1. Incompetence (insufficiency) results from poorly functioning valves
2. Stenosis: results from narrowing of the orifice

Issues: backflow, decreased blood throughout the body

Treatment: Prosthetic Heart Valves (Biological vs. Mechanical)

1. Biological:
   - taken from a pig or human source (new)
   - lasts 8-10 years
   - no anticoagulation drugs
   - no clicking noise
2. Mechanical
   - lasts >20 years
   - lifelong anticoagulation
   - clicking noise

Question 22

What are the coronary arteries? location?

Answer 22

Coronary Arteries:

1. Left coronary artery (very short and post. to pulmonary trunk)
   - Left Anterior Descending Artery
   - Circumflex Artery
2. Right Coronary Artery (very long)
   - Posterior Descending Artery
   - Marginal Branch

Question 23

What does the coronary arteries supply?

Answer 23

Right coronary artery: SA Node, AV node, right atrium, right ventricle

Left Coronary Artery: Anterior aspect of the heart and septum, left atrium, and posterior left ventricle

Question 24

What are the coronary veins? Which Arteries do they travel with and where do they empty into?

Answer 24

Coronary veins –> coronary sinus –> right atrium

Great Cardiac Vein = LAD
Middle Cardiac Vein = PDA
Small Cardiac Vein = Marginal Branch of Right Coronary Artery

Question 25

What type of myocardial infarction would be more severe?

Answer 25

Anterior, because you have the LAD (widowmaker) which supplies most of the heart.

Question 26

Right dominant heart vs. Left dominant heart vs. Co-Dominant Heart, and benefits of that in terms of infarction.

Answer 26

Has to do with the origin of the PDA (posterior descending artery)

Right Dominant: PDA comes from the RCA and it supplies the posterior aspect of the heart (more common)

Left Dominant: PDA is supplied by the circumflex artery, which is a branch of LCA

Co-Dominant: PDA is supplied by both the RCA and the circumflex artery (LCA)

Best to have an infarction with co-dominant, because PDA is supplied by both, if you are left dominant (worse), and right (middle) but tbh all types of blockage is bad

Question 27

What is athlerosclerosis and what is its relationship to a myocardial infarction?

Answer 27

Athlerosclerosis is a gradual buildup of cholesterol and fibrous tissues in the plaques in the walls of arteries.

Rupture of athlesclerotic plaque in a CA –> formation of a clot –> blockage of the artery –> death of the tissue

Question 28

Difference between the infarction and ischemia

Answer 28

Infarction: obstruction of blood supply
Ischemia: lack blood flow

Question 29

Conditions that can cause left ventricular hypertrophy

Answer 29

LV Hypertrophy: enlargement/thickening of the left ventricle
Conditions:
-response to something systemic that causes the left side to pump harder and an increase in the muscle mass, such as athlerosclerosis, hypertension
-increases the risk of MI and stroke