SM 149a - Endocarditis and Pericardial Disease

Question 1

What is Nonbacterial Thrombotic Endocarditis (NBTE)?

Answer 1

Endocarditis caused by deposition of small masses of fibrin, platelets, and other blood components on the leaflets of cardiac valves

Question 2

What are the 3 layers of the semi-lunar valve leaflets?

Answer 2

Fibrosa (Vessel side)

Spongiosa (middle)

Ventricularis (Ventricle side)

Question 3

What are the criteria for diagnosing rheumatic fever?

Answer 3

2 major or 1 major and 2 minor manifestations

• Major = JONES
  
  • Joints (polyarticular arthritis)
  • <3 Carditis
  • Nodules (Aschoff)
  • Erythema Marginatum
  • Syndenhem’s Chorea

Question 4

Describe the pathophysiology of the chronic inflammation associated with Rheumatic Fever?

Answer 4

Chronic inflammation causes…

• Scarring of the heart valves
• The valves become fibrotic
  
  • Almost always mitral, sometimes aortic is involved too
• Commisures fuse
• Chordae tendineae shorten and thicken
• Valvular stenosis and insufficiency
  
  • ​Heart failure
  • Distorted valves
    
    • Potential for infective endocarditis

Question 5

What factors predispose a person to infective endocarditis?

Answer 5

• Abnormal valves
  
  • Prosthetic
  • Damaged by rheumatic fever or other causes
• Turbulent flow
  
  • VSD, other defect
• Bacteremia
  
  • IV drug use
  • Gingivitis
  • Indwelling catheter

Question 6

Which bacteria most commony causes acute bacterial endocarditis?

Answer 6

Staph. aureus

Question 7

Rheumatic fever only occurs following ____________________ infection

Answer 7

Rheumatic fever only occurs following pharyngeal Group A Strep infection

Question 8

______ bacterial endocarditis typically only occurs in people with abnormal heart valves (prosthetic valve, valvular disease)

Answer 8

Subacute bacterial endocarditis typically only occurs in people with abnormal heart valves (prosthetic valve, valvular disease)

Question 9

Which bacteria most commonly causes subacute bacterial endocarditis?

Answer 9

Strep. viridans

Question 10

What is an Aschoff nodule?

If present, it would raise suspicion for which condition?

Answer 10

A nodule made from Anitschkow cells. Aschoff nodules are pathopneumonic for heart disease

(Anitschkow cells have a round or oval nucleolus with chromatin condensed at the nuclear periphery and along the center; they look like owl eyes)

Question 11

What factors predispose a person to Nonbacterial Thrombotic Endocarditis (NBTE)?

Answer 11

• Malignancy (tumor)
• Chronic disease
• Hypercoagulable state
• Scarred or prosthetic valve
  
  • Rarely - valves are usually previously normal

Question 12

What kind of endocarditis is associated with systemic lupus erythematosus?

Answer 12

Libman-Sacks Endocarditis

Question 13

How does inflammation change the appearance of the pericardium?

Answer 13

Normally, the pericardium is transparent and glistening

When inflamed, with will become dull and opaque, with a “sandy” appearance due to pericardial scarring and fibrosis

Question 14

Describe the clinical manifestation of infective endocarditis

Answer 14

• Prolonged fever
  
  • Due to infection
• Heart murmur that changes
  
  • Due to vegetations
• Emboli (possible)
• Immune complex disease (possible)
• Valve rupture (possible)

Question 15

List 4 common types of endocarditis

Answer 15

• Infective endocarditis
• Nonbacterial Thrombotic Endocarditis
• Rheumatic Endocarditis
• Libman-Sacks Endocarditis

Question 16

What causes constrictive pericarditis?

Answer 16

Constrictive pericarditis is post-inflammatory. It develops after subacute pericarditis with effusion.

It evolves over weeks

Question 17

Describe the clinical manifestation of Nonbacterial Thrombotic Endocarditis (NBTE)

Answer 17

Asymptomatic unless embolization occurs

Can embolize to the heart, kidney, speen, and brain

(Vegetations do not affect valve function)

Question 18

Describe the progression of bacterial endocarditis

Answer 18

Presentations can be acute (progresses quickly) or subacute

• Vegetations form on heart valves
  
  • Thrombotic material + microorganisms +
    granulation tissue
• Vegetations can cause partial destruction of the valve
• Vegetations can break off
  
  • Distant ischemic events
  • V. complicated becase they are infectious
    
    • Can cause septic infarct, infected aneurysms

Question 19

What is a jet lesion?

What causes the development of one?

Answer 19

Jet lesions = turbulent backflow that rubs against the endocardium

They can cause thickening and fibrosis of the endocardium, predisposing the individual to endocarditis (bacteria can seed)

Develops in aortic regurgitation

Question 20

Describe the pathologies associated with aging heart valves

Answer 20

• Valves thicken and become less pliable
• Increased collagen content
• Calcification
• Fibrosis of the annulus
• Damage to the endothelial surface due to pressure, flow
  
  • Seeding of bacteria

Question 21

A rapidly develping pericardial effusion will cause cardiac tamponade at about _______cc’s,

while a slowly developing pericardial effusion will not cause cardiac tamponade until there are _____cc’s.

Answer 21

A rapidly develping pericardial effusion will cause cardiac tamponade at about 400 cc’s,

while a slowly developing pericardial effusion will not cause cardiac tamponade until there are 1000 cc’s (1 L).

Question 22

Describe the vegetations associated with Nonbacterial Thrombotic Endocarditis (NBTE)

Answer 22

• Can be small or large
• Usually form on Aortic and Mitral valves, at the line of closure
• Composed of thrombotic material (sterile)
• No effect on valve function
  
  • Cause symptoms when they embolize and cause infarcts in other organs

Question 23

How can rheumatic and non-rheumatic valve disease be distinguished?

Answer 23

• Rheumatic
  
  • Commisures fuse
• Non-Rheumatic
  
  • Commisures become calcified

Question 24

What mitral valve deformity is associated with rheumatic fever?

Answer 24

Fish-mouth deformity

Associated with mitral stenosis caused by rheumatic fever

Question 25

In patients with mitral regurgitation, what pathology (if present) is most likely to lead to sudden cardiac death?

Answer 25

Mitral valve prolapse (often a result of fibrosis)

Note: MI causes fibrosis

Question 26

What complications can arise from infective endocarditis?

Answer 26

• Septicemia
• Emboli
  
  • Heart, Kidney, Spleen, Brain
• Immune Complex Disease
  
  • Kidney
    
    • Hematuria, renal failure
  • Subcutaneous
    
    • Splinter hemorrhage, Osler’s nodes
  • Retina
    
    • Roth spots
• Valve Rupture

Question 27

What is “bread and butter” pericarditis?

What might cause it?

Answer 27

Fibrinous pericarditis associated with rheumatic fever

Question 28

Describe the complications associated with acute rheumatic fever

Answer 28

• CNS involvement
  
  • Sydenham’s chorea
• Polyarticular Arthritis
• Skin changes
• Pancarditis
  
  • Endocarditis + myocarditis + pericarditis
• Valve involvement
• Death
  
  • Rare, but usually due to myocarditis that disrupts the conduction system