Valvular Diseases

Question 1

describe the gross and histological morphology in systemic hypertensive heart disease

Answer 1

• gross:
  
  • concentric hypertrophy of LV
  • 400-600 g
  • long-standing cases → right ventricular hypertrophy and dilation
• histo:
  
  • enlarged myocytes with large hyperchromatic rectangular “box-car” shaped nuclei

Question 2

Answer 2

Question 3

describe clinical features of systemic hypertensive heart disease

Answer 3

• clinical features:
  
  • early stages = asymptomatic
  • angina pectoris
  • signs and symptoms of LHF with progression
  • cerebrovascular accidents (stroke) or renal failure as a consequence of HTN
  • sudden cardiac death

Question 4

describe acute cor pulmonale

Answer 4

• acute cor pulmonale
  
  • pulmonary embolism causing sudden increase in burden on the right heart
  • RV is dilated but no hypertrophy

Question 5

describe causes of chronic cor pulmonale

Answer 5

• chronic cor pulmonale
  
  • COPD = most common cause
  • others: IPF, CF, marked obesity
• morphology:
  
  • RV hypertrophy and often RA hypertrophy +/- dilatation

Question 6

name the etiology of mitral stenosis

Answer 6

Question 7

name the etiology of aortic stenosis

Answer 7

Question 8

name the etiology of mitral regurgitation

Answer 8

Question 9

name the etiology of aortic regurgitation

Answer 9

Question 10

describe signs and symptoms of mitral stenosis vs. mitral regurgitation

Answer 10

• mitral stenosis
  
  • dyspnea (pulm. edema), fatigue, hemoptysis
  • signs: late low pitched diastolic murmur and crepitations in lungs
• mitral regurgitation (MR)
  
  • dyspnea (pulm. edema), palpitation, fatigue
  • signs: pansystolic murmur radiating to axilaa

Question 11

describe signs and symptoms of aortic stenosis vs. aortic regurgitation

Answer 11

• aortic stenosis:
  
  • angina, syncope, CHF
  • signs: ejection systolic murmur loudest at base and radiates to the neck after S1
• aortic regurgitation
  
  • volume overload LHF
  • signs: bounding pulses, early diastolic murmur, displaced apex beat

Question 12

describe the pathogenesis of rheumatic fever

Answer 12

Question 13

describe how rheumatic fever affects the myocardium

Answer 13

• myocarditis:
  
  • paravascular Aschoff bodies:
    
    • central zone of eosinophilic matrix infiltrated by T-cells, plasma cells and activated macrophages within the CT of the heart
  • Anitschkow cells: wavy ribbon-like chromatin (caterpillar cells)
  • giant cells can be seen in all 3 layers of the heart

Question 14

describe how rheumatic fever can affect the endocardium and pericardium

Answer 14

• endocardium:
  
  • edematous and thickened valves with foci of fibrinoid necrosis
  • multiple tiny 1-2 mm wart-like vegetations along the lines of closure of mitral valve; no effect on cardiac fxn
• pericardium:
  
  • fibrinous pericarditis

Question 15

describe how rheumatic fever affects the mitral valve

Answer 15

• chronic mitral valvulitis: most frequent
  
  • conspicuous irregular fibrous thickening (neovascularized) and calcification of the leaflets, often with fusion of the commissures and shortening of the chordae tendinae; fixed narrow opening (fish mouth, buttonhole)
  • mitral stenosis and regurgitation

Question 16

describe how rheumatic fever affects the aortic valve

Answer 16

• chronic aortic valvulitis:
  
  • cusps are thickened, firm and adherent to each other
  • valve orifice is reduced to rigid, triangular channel

Question 17

describe clinical features of chronic rheumatic carditis

Answer 17

• valvulitis (M>A>T>P) murmurs
• cardiac hypertrophy and dilation
• CHF
• arrhythmias
• infective endocarditis

Question 18

describe the diagnosis of RF

Answer 18

Question 19

describe calcific aortic stenosis

Answer 19

• morphology:
  
  • degenerative calcific stenosis (dystrophic calcification)
  • leaflets are rigid and deformed by irregular calcified masses
  • the calcium deposits lie behind the valve cusps and extend into the sinus of Vasalva → coronary ischemia
  • marked LVH

Question 20

Answer 20

Question 21

describe clinical features of calcific aortic stenosis

Answer 21

• due to aortic stenosis:
  
  • angina pectoris: increased requirement of hypertrophied myocardium
  • syncope: poor perfusion of the brain
  • death usually occurs due to CHF or arrhythmias

Question 22

there is an intrinsic defect of ____ in mitral valve prolapse

Answer 22

there is an intrinsic defect of connective tissue synthesis and remodeling in mitral valve prolapse

Question 23

describe the morphology of mitral valve prolapse

Answer 23

• morphology:
  
  • soft pulled up rubbery mitral valve cusps
    
    • ballooning of the valve leaflets into the LA during systole (mid-systolic click)
  • the chordae tenindae, which are often elongated and fragile, may rupture in severe cases
  • the mitral annulus may be dilated (regurgitation)

Question 24

Answer 24

Question 26

describe clinical features of mitral valve prolapse

Answer 26

* most patients are asymptomatic * palpitations * fatigue or atypical chest pain * midsystolic click -- abrupt tension on leaflets and chordae when valve tries to close * severe complications in about 3% of cases: * mitral regurgitation and CHF * IE * ventricular arrhythmias (may lead to SCD) * thromboemboli stroke * rarely syndrome characterized by scoliosis and high arched palate

Question 27

describe acute endocarditis

Answer 27

* _acute endocarditis_ * typically, infection of **previously normal** valve * destructive and fulminant * caused by highly virulent organisms * mortality is high despite antibiotics and/or surgery

Question 28

describe subacute endocarditis

Answer 28

* subacute endocarditis * infxn of **previously** **abnormal valve** (deformed valves) * less destruction * caused by low virulent organisms * most patients recover with appropriate therapy

Question 29

name the causative organisms in native valve IE

Answer 29

Question 30

name the causative organisms involved in prosthetic valve IE

Answer 30

Question 31

describe the pathogenesis of IE

Answer 31

Question 32

name predispoing factors for infective endocarditis

Answer 32

* preexisting cardiac abnormality: * rheumatic valvular disease * mitral valve prolapse * congenital defects * degenerative calcific aortic stenosis * prosthetic heart valves * IVDU = **tricuspid valve** * transiet bacteremia: * dental procedures, urinary catheterization, endoscopy

Question 33

describe the complications and host consequences caused by persistent bacteremia (as a consequence of vegetation)

Answer 33

Question 34

describe the complications and host consequences caused by tissue destruction (as a consequence of vegetation)

Answer 34

Question 35

describe the complications and host consequences caused by fragmentation (as a consequence of vegetation)

Answer 35

Question 36

describe the complications and host consequences caused by release of bacterial antigen (as a consequence of vegetation)

Answer 36

Question 40

\_\_\_\_ are the classic hallmark of IE and are prone to ___ that can lead to \_\_\_\_\_ explain this

Answer 40

**vegetations** are the classic hallmark of IE and are prone to **embolization → septic infarcts, abscesses, mycotic aneurysms** * friable, bulky, potentially destructive lesions * contain fibrin, inflammatory cells, bacteria

Question 42

Answer 42

Question 46

describe general features associated with IE

Answer 46

* fever * clubbing of fingers * splinter hemorrhages under nail beds * Osler nodes: tender (painful) subcutaneous nodules * Janeway lesions: nontender (not painful) maculae on palms and soles * Roth spots: retinal hemorrhages with clear center * systemic embolization → stroke, distal organ infarcts

Question 47

name clinical features associated with acute bacterial endocarditis

Answer 47

* _acute bacterial endocarditis_ * high grade fever with chills * new cardiac murmur * features of septicemia * _subacute bacterial endocarditis_ * low grade fever; malaise * changing cardiac murmurs * weight loss * splenomegaly

Question 48

describe the diagnosis and treatment of IE

Answer 48

* diagnosis * Duke criteria * repeated blood cultures for both aerobic and anaerobic organisms * echocardiography * treatment * difficult infxn to eradicate because of the avascular nature of the valves * antibacterial therapy (IV, long term)

Question 49

describe nonbacterial thrombotic endocarditis (NBTE)

Answer 49

* characterized by the presence of sterile thrombi on the leaflets of previously normal valves * encountered in debilitated patients e.g. cancer (hence the name **marantic (from marasmus) endocarditis**) * usually asymptomatic

Question 50

describe the pathogenesis and complications of NBTE

Answer 50

* pathogenesis: * associated with endothelial abnormalities, hypercoagulable states, adenocarcinomas * complications: * embolization and IE

Question 52

describe Libman-Sacks endocarditis

Answer 52

* characterized by presence of sterile vegetations on the cardiac valves in patients of SLE **(LSE in SLE)** * deposition of immune complexes

Question 53

describe complications of mechanical prosthetic valves

Answer 53

* complications: * thrombo-embolism * life anticoagulation → hemorrhage * IE * RBC destruction (hemolysis) * inadequate healing → paravalvular leak

Question 54

describe complications of tissue valves (bioprostheses)

Answer 54

* no anticoagulation needed * complications * less durable: matrix deterioation, rigidity, calcification → stenosis, can perforate * IE * inadequate healing → paravalvular leak