Valvular Disease - Aortic Regurgitation

Question 1

What is Aortic regurgitation?

Answer 1

https://www.youtube.com/watch?v=JorBOLNzfUY

Aortic regurgitation is reflux of blood from the aorta through the aortic valve into the left ventricle during diastole

Question 2

How does the heart compensate for aortic regurgitation?

Answer 2

Net cardiac ouput is reduced - total volume of blood pumped into the aorta must increase, and consequently the left ventricular size must enlarge

Question 3

What happens to diastolic BP in aortic regurgitation?

Answer 3

Decreases due to diastolic backflow

Question 4

What happens to coronary perfusion in Aortic regurgitation?

Answer 4

Decreases

Question 5

What are causes of acute aortic regurgitation?

Answer 5

• Acute rheumatic fever
• Infective endocarditis
• Aortic dissection
• Ruptured sinus of valsalva
• Prosthetic valve failure
• Chest trauma

Question 6

What are causes of chronic aortic regurgitation?

Answer 6

• Rheumatic heart disease
• Syphilis
• Seronegative Arthitidies
• Hypertension
• Bicuspid Aortic valve
• Takayasu’s Arteritis
• Connective tissue disorders
• RA
• Osteogenesis imperfecta

Question 7

What seronegative arthritidies can cause chornic aortic regurgitation?

Answer 7

• Ankylosing spondylitis
• Reiter’s syndrome
• Psoriatic arthritis

Question 8

What connective tissue disorders can cause Aortic regurgitation?

Answer 8

• Marfan’s syndrome
• Ehler’s danlos syndrome

Question 9

When do symptoms begin to develop in aortic regurgitation?

Answer 9

When there is significant left ventricular failure

Question 10

What are symptoms of aortic regurgitation?

Answer 10

• Exertional dyspnoea
• Orthopnoea
• Paroxysmal nocturnal dyspnoea
• Palpitations
• Angina
• Syncope
• CCF

Question 11

Why do those with Aortic regurgitation suffer from PND and orthopnoea?

Answer 11

Due to the development of CHF

Question 12

Why does angina occur in Aortic regurgitation?

Answer 12

Due to a combination of decreased perfusion due to regurgitation and increased work from the heart to maintain cardiac output

Question 13

What signs might you see in someone with Aortic Regurgitation?

Answer 13

• Collapsing pulse
• Wide pulse pressure
• Displaced, hyperdynamic apex beat
• High pitched, early diastolic murmur
• Eponymous Signs

Question 14

Why would you get a collapsing pulse in AR?

Answer 14

As the ventricle finishes contracting, blood regurgitates back through the incompetent valve rather than being maintained

Question 15

Why is pulse pressure widened?

Answer 15

The high pulse pressure can be attributed to the high-volume flow from the left ventricle into the ascending aorta during systole. The diastolic decay of the pulse is attributed to the backflow into the ventricle and to forward flow through peripheral arterioles

Question 16

Why does someone with aortic regurgitation have a displaced, hyperdynamic apex?

Answer 16

Due to both concentric and eccentric hypertrophy

Question 17

When is the murmur of AR heard?

Answer 17

Diastole

Question 18

What is the mechanism behind the murmur of aortic regurgitation?

Answer 18

The characteristic murmur is the sound of blood moving back across the damaged aortic valve.

Question 19

What is Quincke’s sign?

Answer 19

Exaggerated pulsations of the capillary nail bed. May be accentuated by depressing and releasing the distal end of the nail

Question 20

What is Demusset’s sign?

Answer 20

Rhythmic head bobbing in synchrony with the heart beat

Question 21

What are pistol shot femorals?

Answer 21

A sharp bang heard on auscultation over the femoral arteries in time with each heart beat.

Question 22

What investigations might you do in someone with suspected AR?

Answer 22

• ECG
• CXR
• ECHO
• Cardiac MRI

Question 23

What might you see on ECG in someone with AR?

Answer 23

LVH - tall R waves and deeply inverted T waves in the left-sided chest leads, and deep S waves in the right-sided leads

Question 24

What might you see on CXR in someone with AR?

Answer 24

• Left ventricular enlargement +/- dilatation of the ascending aorta
• Calcified ascending aortic wall - Syphilis

Question 25

How would you manage someone with Aortic Regurgitation?

Answer 25

Main goal is to reduce hypertension to delay surgery * **ACEi** Surgery * **Aortic valve replacement**

Question 26

What happens to LV end systolic and end diastolic volume in AR?

Answer 26

Both increase

Question 27

What happens physiologically in acute AR?

Answer 27

The LV does not have sufficient time to dilate, resulting in LV end-diastolic pressure increases rapidly. This causes an increase in pulmonary venous pressure and altering coronary flow dynamics. As pressure increases throughout the pulmonary circuit, the patient develops dyspnea and pulmonary oedema. In severe cases, heart failure may develop and potentially deteriorate to cardiogenic shock. Decreased myocardial perfusion may lead to myocardial ischemia.

Question 28

What happens physiologically in Chronic AR?

Answer 28

Causes gradual LV volume overload that leads to LV enlargement and eccentric hypertrophy. The LV becomes larger and more compliant, with greater capacity to deliver a large stroke volume that can compensate for the regurgitant volume. The resulting hypertrophy is necessary to accommodate the increased wall tension and stress that result from LV dilation (Laplace law). Eventually, the LV reaches its maximal diameter and diastolic pressure begins to rise, resulting in symptoms (dyspnea) that may worsen during exercise. Increasing LV end-diastolic pressure may also lower coronary perfusion gradients, causing subendocardial and myocardial ischemia, necrosis, and apoptosis. Grossly, the LV gradually transforms from an elliptical to a spherical configuration.

Question 29

What changes occur to the ejection fraction in chronic AR?

Answer 29

## Footnote During the early phases of chronic AR, the LV ejection fraction (EF) is normal or even increased (due to the increased preload and the Frank-Starling mechanism). As AR progresses, LV enlargement surpasses preload reserve, with the EF falling to normal and then subnormal levels. The LV end-systolic volume rises.

Question 30

What is Corrigan's pulse?

Answer 30

Collapsing pulse in the arm

Question 31

What mnemonic can you use to remember the main causes of aortic regurgitation?

Answer 31

* **R**heumatic heart disease * **E**ndocarditis * **A**nkylosing SPondylitis * **L**uetic heart disease (syphilis) * **M**arfans Syndrome