Cardiology Lecture 3 -- Aortic Valve Lesions

Question 1

Effect of aortic stenosis on left ventricle

Answer 1

LV hypertrophies to get blood out through the small aortic valve = increase in ventricular presure (>> aortic P)

Question 2

Aortic stenosis: type of overload

Answer 2

Pressure overload condition

Question 3

Heart sound produced by aortic stenosis

Answer 3

S4

Question 4

Carotid artery pulse in presence of aortic stenosis

Answer 4

Parvus entardus (low V and late upstroke; mimics aorta)

Question 5

3 pressure gradients associated with aortic stenosis (graph)

Answer 5

Peak-to-peak gradient Peak-instantaneous gradient Mean gradient

Question 6

Which P gradient is the most clinically relevant for aortic stenosis

Answer 6

Mean gradient

Question 7

What does the mean gradient represent?

Answer 7

Intensity of the murmur (higher gradient = higher murmur intensity)

Question 8

Normal surface area of aortic valve

Answer 8

3 - 4 cm^2

Question 9

Surface area of severely stenotic aortic valve

Answer 9

<1 cm squared

Question 10

Why shouldn’t you ever gauge severity of aortic stenosis by the intensity of the murmur?

Answer 10

Soft murmur can occur in left ventricular heart failure even if AS is severe

Question 11

Cardinal symptoms of aortic stenosis

Answer 11

Angina Syncope Dyspnea

Question 12

Define angina

Answer 12

Tightness in chest with effort

Question 13

Survival expectancy if a patient with aortic stenosis presents with angina

Answer 13

5 years

Question 14

Survival expectancy if a patient with aortic stenosis presents with syncope

Answer 14

3 years

Question 15

Survival expectancy if a patient with aortic stenosis presents with dyspnea

Answer 15

2 years

Question 16

What is the significance of cardinal symptoms?

Answer 16

Surgery is required for survival benefit; symptoms = poor prognosis

Question 17

In elderly patients, what can lead to stenosis?

Answer 17

Sclerosis

Question 18

Describe the murmur found in aortic stenosis

Answer 18

Systolic ejection murmur Crescendo mimics LV-Aorta P gradient (orange area)

Question 19

Following a PVC (extra contraction), how does the murmur of aortic stenosis behave?

Answer 19

Murmur directly following PVC increases in intensity due to increased LV volume, which leads to lincreased LV pressure and thus an increased LV-Aortic P gradient

Question 20

Where to listen for aortic stenosis

Answer 20

Right upper sternal border (2nd right intercostal space)

Question 21

Potential S2 behavior in aortic stenosis

Answer 21

May be split due to aortic valve closing later than pulmonary

May be absent

Question 22

Describe palpation findings for aortic stenosis

Answer 22

Sustained beat throughout systole with S4 at apex

Question 23

Treatment for aortic stenosis

Answer 23

Replacement of aortic valve

Question 24

When must you do surgery on a patient with aortic stenosis?

Answer 24

Symptomatic

OR

Asymptomatic by with very low EF (high risk of sudden cardiac death)

Question 25

2 types of aortic regurgitation

Answer 25

Acute

Chronic

Question 26

Most common cause of chronic aortic regurgitation

Answer 26

Bicuspid aortic valve

Question 27

2 categories of causes for aortic regurgitation

Answer 27

Aortic root/ descending aorta dilation

Aneurysm of aortic valve

Question 28

Cause of chronic aortic regurgitation due to aortic root/descending aorta dilation

Answer 28

Marfan’s Syndrome

Question 29

Cause of aortic valve aneurysm-induced chronic aortic regurgitation

Answer 29

Familial aortopathy

Question 30

Chronic aortic regurgitation: type of overload

Answer 30

Combination of pressure and volume overload

Question 31

Why is chronic aortic regurgitation a V overload condition?

Answer 31

LV preload increases (2 sources of incoming blood, mitral valve AND aortic valve)

Question 32

Why is chronic aortic regurgitation a P overload condition?

Answer 32

Ejection of huge blood volumes increases LVP ude to increased SV so aortic P increase = afterload increases

Question 33

What patients have the biggest hearts at autopsy? (bovine heart)

Answer 33

Patients with chronic aortic regurgitation

Question 34

Clinical hallmark of chronic aortic regurgitation

Answer 34

Diastolic blowing descrescendo murmur

Question 35

Explain the behavior of the murmur in chronic aortic regurgitation

Answer 35

Murmur mirrors hemodynamics. Descrescendo is due to increased gradient between aorta and left ventricle at beginning of diastole and decreased gradient at beginning of systole (a nearly perfectly straight descent)

Question 36

Where to listen for chronic aortic regurgitation

Answer 36

Left or right sternal border

Question 37

Most common symptoms of chronic aortic regurgitation

Answer 37

Fatigue

Dyspnea

May have chest pain

Question 38

Palpation findings of chronic aortic regurgitation

Answer 38

Apex may have sustained or diplaces pulse

Question 39

Treatment for chronic aortic regurgitation

Answer 39

Surgery

Question 40

When must patients with chronic aortic regurgitation get surgery?

Answer 40

Symptomatic

OR

Asymptomatic with low EF (rule of 55; EF < 55%)

Question 41

3 possible causes of acute aortic regurgitation

Answer 41

1. Valvular infection (endocarditis)
2. Trauma (aorta rips)
3. Aneurysm (aorta tears)

Question 42

Describe the behavior of the pressure gradients in acute aortic regurgitation

Answer 42

Since the heart has never experienced this backflow of blood before, LV tries to compensate by increasing diastolic P precipitously to meet aortic P (i.e. the LV does not suddenly become compliant like it is in chronic aortic regurgitation)

Question 43

Describe the murmur in acute aortic regurgitation and explain why it is this way

Answer 43

Mumur is short since the P gradient in absent at the end of diastole due to the rise of LVP to meet aortic P

Question 44

What is the reason for peripheral findings in chronic aortic regurgitation

Answer 44

High pulse pressure due to high systolic and low diastolic P