Valvular Heart Disease

Question 1

Which valves are the semilunar valves? How many cusps do they each have? What does their function/integrity depend on?

Answer 1

Aortic and Pulmonary Valves
3 cusps each
Function depends on integrity and coordinated movements of cusps and attachments

Question 2

Which valves are the atrioventricular valves? How many cusps do they each have? What does their function/integrity depend on?

Answer 2

Tricuspid and Mitral
3 (tricuspid) and 2 (mitral)
Competency depends on leaflets + annulus, chordae tendinae, papillary muscles, ventricular wall

Question 3

What is the valve leaflet core made of?

Answer 3

Collagen, elastin, ECM

Question 4

What is the valve lined by on both the inflow and outflow tracts?

Answer 4

Endocardium

Question 5

Bicuspid Aortic Valve

Describe what the problem is and what pathology it can lead to

Answer 5

Congenital disorder in which two cusps of the aortic valve have a midline raphe uniting them where they should normally be separated

Higher risk of developing aortic stenosis (in 50s or 60s) and infective endocarditis
May develops aortic dissections and aneurysms at higher rate

Question 6

Valvular Degeneration due to Calcification

What causes it?

Answer 6

Normal “wear and tear” on the heart valves (there is some injury to the valves and they heal with fibrosis)

Atherosclerotic risk factors may also contribute to the development of this disease

Question 7

Describe the problems caused by Calcific Aortic Stenosis

Answer 7

Calcified masses form on the aortic cusps, which prevent their opening, There is outflow obstruction and therefore an increased pressure gradient across the valve. Leads to concentric LV hypertrophy

Question 8

Mitral Valve Prolapse is AKA…

Answer 8

Myxomatous Degeneration of Mitral Valves

Question 9

Mitral Valve Prolapse

Describe the basic problem

Answer 9

Floppy, enlarged mitral valves leaflets balloon into the LA during systole
Can cause injury to the LA endothelium

Question 10

What would you see on histology of mitral valve prolapse?

Answer 10

Deposition of extracellular mucus (myxomatous deposition within the valve tissue core)

Question 11

What genetic disorder could lead to a greater risk of mitral valve prolapse?

Answer 11

Marfan’s Syndrome (fibrillin defect)

Question 12

What would you hear on auscultation in mitral valve prolapse?

Answer 12

Midsystolic click from the valves ballooning into the atria during systole

Question 13

Who most commonly is diagnosed with mitral valve prolapse? What do they normally present with?

Answer 13

Young women, commonly asymptomatic with no long term complications

Some have nonspecific symptoms (chest pain, dyspnea, fatigue)

Question 14

What are some serious complications of mitral valve prolapse?

Answer 14

Infective endocarditis
Mitral insufficiency
Stroke/systemic infarct
Embolism of a valve leaflet
Arrhythmias

Question 15

What is infective endocarditis? What is the characteristic finding?

Answer 15

Destructive inflammation of cardiac valves and endocardium, commonly due to bacterial infection

Vegetations growing on valve leaflets are common

Question 16

What is a vegetation? What is it composed of?

Answer 16

Abnormal outgrowth of a body part, commonly made of fibrin and collagen with inflammatory cells and thrombotic debris

Question 17

What is a common complication of a vegetation formed on a valve?

Answer 17

Embolization (the thrombi formed on the vegetations are not strong)

Question 18

Acute IE
Most common cause?
Prior condition of valve?
Outcomes?

Answer 18

Usually Staph aureus infection.
Rapid and severe destruction of a previously normal valve
High mortality

Question 19

Subacute IE
Most common cause?
Prior condition of valve?
Outcomes?

Answer 19

Usually a low virulence organism (like Strep. viridans)
May affect a previously deformed valve
Does not destroy valve quickly and responds well to antibiotics

Question 20

Who are patients at greater risk for infective endocarditis?

Answer 20

Valve disease
Prosthetic valves
Immune deficiency
Diabetes
IVDAs
Alcoholics

Question 21

How does the infectious organism in infective endocarditis enter the body?

Answer 21

May come from an infection elsewhere.
Dental or surgical procedures with bacteremia.
Injection of contaminated materials into blood.

Question 22

Symptoms of Endocarditis

Answer 22

Chest pain
SOB
New Murmur
See vegetations on echo
Blood cultures show bacteremia
Splinter hemorrhages in the nailbeds
Conjunctival petechiae
Janeway lesions (nontender darkened areas on palms and soles)
Osler Nodes (immune deposition in hands and feet)

Question 23

What are the 3 situations where a vegetation could occur outside of an infection?

Answer 23

Nonbacterial Thrombotic Endocarditis
Endocarditis of SLE
Acute Rheumatic Fever

Question 24

Nonbacterial Thrombotic Endocarditis

What is the clinical problem?

Answer 24

Sterile thrombi (vegetations) forming on valve leaflets
Small, nondestructive, loosely attached

Question 25

In what patients does Nonbacterial Thrombotic Endocarditis most commonly occur?

Answer 25

Patients in a hypercoagulable state | sepsis, cancer, burns, indwelling catheters

Question 26

Nonbacterial Thrombotic Endocarditis | What complication are you worried about?

Answer 26

Embolization of the thrombus leading to infarcts or stroke

Question 27

Endocarditis of Systemic Lupus Erythematosus (SLE) | What is the clinical problem?

Answer 27

Immune complex deposition and inflammation on valve leaflets (vegetations) Causes "Valvulitis" to harm/destroy valve

Question 28

Rheumatic Fever | What infection can cause this? How are these vegetations formed?

Answer 28

Group A Strep (S. pyogenes) infection that is untreated can lead to rheumatic fever Antibodies are generated against strep M proteins, which have some cross reactivity to self antigens in the heart, leading to inflammation of the heart

Question 29

Major Manifestations of Rheumatic Fever

Answer 29

``` JONES Migratory polyarthritis Carditis/Pancarditis Subcutaneous nodules Erythema marginatum Sydenham's Chorea ```

Question 30

Minor Manifestations of Rheumatic Fever

Answer 30

Fever Arthralgia Elevated acute phase reactants

Question 31

How do you confirm rheumatic fever diagnosis?

Answer 31

2 major manifestations OR 1 major + 2 minor manifestations

Question 32

What is pancarditis?

Answer 32

Inflammatory involvement of the pericardium, myocardium, and endocardium

Question 33

What is seen histologically in the acute phase of rheumatic fever?

Answer 33

Aschoff Bodies | composed of T cells, plasma cells, macrophages (caterpillar cells = Anitschkow cells)

Question 34

Which valve does chronic rheumatic heart disease typically involve? What happens?

Answer 34

Mostly on the L heart, mostly mitral. Valve leaflet fibrosis and fusion. Chordae tendinae become short, thick, and fused.