VALVULAR HEART DISEASEVALVULAR HEART DISEASE

•Causesa) stenosis

i) “narrowing” and failure of forward flow

b) insufficiency (regurgitation, incompetence)

i) failure of valve to close completely

- allowing reverse flow

c) Purei) stenosis or regurgitation

d) mixedi) stenosis and regurgitation coexist in same valve

- usually 1 defect predominates

e) isolatedi) 1 valve

f) combinedi) more than 1 valve

dysfunctional

g) flow anomalies through valves produce turbulent flow

patternsi) murmurs

h) acquired valvular heart diseasei) see table 12-7see table 12-7

**ii) students should be able to match various heart

valve diseases with both the specific valve involved and whether the disease is a stenosis, regurgitation or both

iii) most frequent causes:- ASAS calcification of congenitally deformed

valve

- AIAI dilation of ascending aorta (e.g., hypertension and aging)

- MSMS RHD

- MIMI mitral valve prolapse

(myxomatous degeneration)

CalcificationCalcification

• valves subjected to repetitive stresses

a) at hinge points of cusps and leafletsi) 75 bpm x 60 mins = 4500 bphii) 4500 bph x 24 hrs = 108,000

bpdiii) 108,000 bpd x 365 days = ~40 million bpyiv) 40 million bpy x 75 yrs = 3

billion bp your life !

b) deformations during each beatc) pressures on valves in closed

phasei) 120 mmHg mitral valveii) 80 mmHg aortic valve

d) the factors listed above (a,b,c) contribute to valvular damage

seen by calcium deposits (Calcium Phosphate)

i) 10 dystrophic calcification (different from

atherosclerosis)- calcific AS- mitral annular

calcification

• Calcific Aortic StenosisCalcific Aortic Stenosisa) most common of all valvular abnormalities

i) geriatric (“wear and tear”) of normal valve or

congenital bicuspid aortic valveb) incidence due to agec) incidence of RF in No. America

i) < 10% of acquired stenosisd) 6-7th decades (bicuspid valve)e) 8-9th decades (normal valve)

i) “senile calcific aortic stenosis”

f) Clinical:i) LV outflow obstruction

- LV compensates by LVP to ~ 200 Hg develops- LV concentric

hypertrophy (pressure overload !!):

CHF- ischemic myocardium - angina may appear- systolic and diastolic impairment (e.g.,

syncope) ii) the S & S above indicate

decompensation (poor progno.)

g) 50% die within 5 yrs with angina

h) 50% die within 2 years with CHF

i) patients w/out symptoms have excellent outcome

i) symptoms are critical factors

in management and outcome !!• Calcific stenosis of CongenitallyCalcific stenosis of Congenitally Bicuspid Aortic ValveBicuspid Aortic Valve

a) frequency ~ 1.5% live birthsb) NOT symptomatic at birth or

through early lifec) 2 leaflets. 1 is larger

i) larger leaflet increases calcificationii) once stenosis occurs,

progression is similar to normal aortic valve

d) bicuspid aortic valves may be acquired (RHD) fused

leafletse) other causes of bicuspid aortic valve incompetence

i) aortic dilationii) cusp prolapseiii) infective endocarditis

AA. Acquired bicuspid aortic valve with secondary calcification. At the center of the conjoined cusp (lower center) are elements of two preexisting cusps, now fused. B.B. Congenital bicuspid valve. The characteristic raphe of the congenital bicuspid aortic valve appears at the lower portion of the figure. C.C. Senile type. None of the commissures is fused, but there is a major intrinsic calcification of the three cusps. D.D. Unicuspid, unicommissural congenital aortic stenosis with secondary calcification.

AA BB

CC DD

Calcific aortic stenosis occurring on a congenitally bicuspid valve. One cusp has a partial fusion at its

center, called a raphe (arrow).

• Mitral Annular CalcificationMitral Annular Calcificationa) calcific nodules arounf fibrous annular ring of mitral valveb) usually does not affect valvular function

i) rare cases:- stenosis- regurgitation- sudden death (Ca++ dependent)- thrombus formation (stroke) and infections

c) women > 60 yrs, LVP, mitral valve prolapse, hypertrophic

cardiomyopathy

Myxomatous Degeneration of Myxomatous Degeneration of Mitral Mitral Valve (Mitral Valve Prolapse)Valve (Mitral Valve Prolapse) • ballooning back during systole• one of most common valvular heart diseases

a) incidence in womenb) usually presents as incidental finding on physical exam

c) affected leaflets are thickenedi) due to mucoid deposits (“MyxomatousMyxomatous”)ii) cords are usually elongated thinned and often rupturediii) annular dilation

characteristic- leaflets balloon- rare in other

mitral insufficienciesiv) thrombi formation

- behind ballooned cusps (on leaflets)

d) clinical:i) most asymptomatic

- midsystolic “click”ii) ~3 % develop

complications:- infective endocarditis- mitral insufficiency (requiring surgery)- stroke- arrhythmias (atria &

ventricular - - “sudden death”)

iii) if complications surgery

Rheumatic Fever and Heart Rheumatic Fever and Heart DiseaseDisease

• RFRF is acute inflammationa) within weeks following group A streptococcal pharyngitis

i) cross reaction of Ab directed at M proteins of Strep. proteins with glycoprotein

Ag in heart, etc.b) acute carditis (RF) may develop

to chronic RHDRHD

c) consequence of RF is chronic valvular deformities

(fibrosis)i) mitral and aortic

- mainly mitral stenosis- permanent

• Pathology:a) RF focal inflammatory lesions

i) “Aschoff” bodies- swollen eosinophilic collegen- found is any layer of the heart (“pancarditis” - in pericardium

fibrinous or serofibrinous exudate

ii) “Anitschkow” cells- swollen macrophages and/or plasma cells

b) RHD – chronici) organized acute

inflammation- fibrosis

ii) leaflet thickeningiii) commissure fusion

(stenosis)- “buttonhole” or “fishmouth” stenoses

iv) cord fusion / thickening v) Aschoff bodies replaced

with fibrous scar

Stenotic mitral Valve seen fromleft atrium. Bothcommissures arefused; the cuspsAre severely thickened.The left atrium is huge. The valve is both incompetent and stenotic

Opened stenotic mitral valveshowing thickeningdistorted cusps,adherentcommissures withcalcification andthrombusdeposition, andthickening, fusionand shortening ofchordae tendinae

vi) major cause of mitral stenosis

- ~ 99% - mitral valve alone ~ 70%- mitral / aortic valve ~

25%c) etiology unknown

i) believed to result from connective tissue defects

- in Marfan Syndrome

• Clinical:Clinical:a) migratory polyarthritis

i) large jointsb) carditisc) s.c. nodulesd) erythema marginatume) Chorea movements (CNS) (Sydenham Chorea) (“St. Vitus Dance”)

s.c. nodule

Infective EndocarditisInfective Endocarditis

• Most cases are bacterial• Classification based on clinical grounds

a) acutei) destructive (necrotic,

ulcerative) valvular infections

ii) highly virulentiii) frequently of healthy valveiv) ~ 50% lethal: days to

weeks - despite

antibiotics/surgery

b) Subacutei) low virulenceii) recovery with antibiotic Txiii) vegetative growths show

signs of healing

• Etiology and Pathogenesisa) may develop on normal valvesb) most develop as result of:

i) RHDii) myxomatous mitral valve

- most common today

iii) other factors- calcific stenosis- prosthetic valves- bicuspid aortic valve- immunodeficiency- neutropenia- diabetes- alcohol

c) causative organismsi) Strep viridans (50-60%)

- previously damaged native valve

ii) Staph aureus (10-20%)- found on skin- virulence- attack normal or

damaged valves- i.v. drug users !!

iii) HACEK group- Haemophilus - Actinobacillus- Cardiobacterium- Eikenella- Kingella

iv) Prosthetic valves- Staph epidermidis- Staph aureus

v) gram (-) bacilli and fungi Seeding of blood with microbes main cause

a) dental or surgical procedures, etc• Aortic and mitral valves most common

a) right sided valves in i.v. drug abusers

• Clinical:a) rapid fever (acute IE)

i) chillsii) weaknessiv) immune mediated GNv) murmurs (~90%)

- left side lesionsb) subacute (mild or absent To)

- fatigue- flu-like symptoms- weight loss

Common Manifestations of Infective Endocarditis.Splinter hemorrhages (Panel A) are normally seen under the fingernails. Panel B shows conjunctival petechiae.Osler's nodes (Panel C) are tender, subcutaneous nodules, often in the pulp of the digits or the thenar eminence.Janeway's lesions (Panel D) are nontender, erythematous, hemorrhagic, or pustular lesions, often on the palms or soles.

Non Infective EndocarditisNon Infective Endocarditis

• Nonbacterial Thrombotic Endocarditis (NBTE)

a) sterile, nondestructive b) small masses of fibrin,

platelets, etc.i) on leaflets of cardiac valves

c) often seen in debilitated ptsi) cancer

d) may produce embolii) stroke in brain, heart, etc.

e) frequently occur with DVT and PE

i) common origin with hypercoagulable states - may be related to some

underlying disease, such as pancreatic cancer, leukemia, burns and sepsis,

DIC- indwelling catheters (SG) induce right valve

lesions

• Libman-Sacks Diseasea) associated with the

autoimmune disease SLEi) mitral and aortic valves

- mitral more common- underneath valves- on cords

b) sterile vegetationsc) regurgitation

• Carcinoid Heart Disease a) associated with systemic

syndrome caused by carcinoid tumors

i) ~ 50% of patients with carcinoid syndrome- flushing of skin- cramps- vomitting- diarrhea

i) endocardiumii) valves of right heart

(~90%)b) serotonin correlate with

severity