Valvular and Congenital Heart Disease - Nichols and Newman Flashcards
What are the two forms of cardiac adaptation to valvular disease? How is this different in acute scenarios?
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Concentric hypertrophy: pressure overload = STENOSIS (+ HTN)
1. INC thickness (thich walls), but normal volume -> LV hypertrophy -
Eccentric hypertrophy: volume overload = REGURGITATION
1. INC dilation of chamber (more volume + thin walls) -> INC output (Starling) -
Acute: no time to adapt, so pt presents severely ill
1. Murmur heard, but no concentric or eccentric hypertrophy - INC pressure change with DEC structural changes in acute OR DEC pressure change with INC structural changes in chronic
Mitral valve stenosis
- Rheumatic fever
- INC pressure behind mitral (stenosed) valve: concentric hypertrophy + dilation of LA (THROMBI), pulmonary HTN (atherosclerosis), concentric hypertrophy of RV
- Presentation: shortness of breath, alveolar fluid w/fibrinous material, hemoptysis (if chronic), right heart failure, afib (stroke), dysphagia (atrium compresses back on esophagus)
- Murmur: diastolic
Mitral valve regurgitation
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Mitral valve prolapse, LV dilation (left sided heart failure dilates mitral valve ring), rheumatic fever
1. Prolapse: leaflets replaced by myxomatous (spongy) tissue; eccentric hypertrophy (dilation) of LA - Presentation: can be asymptomatic with murmur, sudden rise in atrial pressure, INC preload (from atrium) + DEC afterload (from venting) = INC stroke volume
- Acute = no change in RA volume, INC pulmonary capillary wedge pressure (lg pressure buildup)
- Murmur: pansystolic
What are the epi, patho and sign of mitral valve prolapse?
- Epi: most common valvular disease (about 2% of US population); primary or secondary
- Pathogenesis: primary form a genetic defect in connective tissue; secondary form injury
- Gross: redundant, billowing, ballooning, hooding, floppy leaflets, +/- elongated chordae tendineae (that can rupture)
- Microscopic: sometimes degeneration of and attenuation of outer zona fibrosa, and expanded myxomatous inner zona spongiosa (often normal)
- Sign: mid-systolic click
What are 1, 2, and 3?
- Normal mitral valve
1. Zona atrialis (sometimes also called zona fibrosa)
2. Zona spongiosa
3. Zona fibrosa
What do you see?
Expanded, myxomatous zona spongiosa (e.g., in mitral valve prolapse)
What are the epi and patho of Libman-Sacks endocarditis?
- Epi: lupus
- Gross: small-medium verrucous, berry-like or flat vegetations, commonly on multiple valves (on either or both sides)
- Microscopic: necrotic debris, fibrinoid material, degenerating leukocytes, fibroblasts, and hematoxylin bodies
- Clinically important fact: rarely embolizes
How is endocarditis related to valve pressure?
- Incidence of infection, marantic endocarditis, and rheumatic disease on a valve correlate with resting pressure on the closed valve:
1. Mitral: 116 mm Hg
2. Aortic: 72 mm Hg
3. Tricuspid: 24 mm Hg
4. Pulmonic: 5 mm Hg
Why is it really important to “catch” infective endocarditis?
100% fatal if undiagnosed/untreated, but only 20% fatal if diagnosed/treated appropriately (IV AB’s, sx)
What is the pathogenesis of infective endocarditis (4)?
- Most commonly of the valves, w/vegetations -> friable masses of infecting organisms and blood clot
1. Valvular endo injury
2. Platelet + fibrin deposition
3. Microbial seeding
4. Microbial multiplication - NOTE: valves may be “grossly normal,” but steps 1 and 2 precede 3 and 4
What valves, etiologic agents, and portals of entry are generally involved in infective endocarditis?
- Valves: mitral > mitral + aortic = aortic > tricuspid (only 1% pulmonic)
- Etiologic agents: staph aureus (acute) and strep viridans (sub-acute; followed by enterococcus)
What do you see? Why is this important?
- Central venous catheterization
- Portal of entry of bugs in infective endocarditis
What do you see? Why is this important?
- Mouth with gingivitis, brushing teeth, chewing, dental procedures -> all portals of entry for bugs in infective endocarditis
What is the gross pathology of infective endocarditis?
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Vegetations: large (up to 3cm), friable, single or multiple, tan, grey, or red brown
1. Usually on line of valve closure (atrial side of AV valves, and ventricular side of semilunar valves) - The larger a vegetation, the more likely it is infective
- Destructive, and may cause: perforation of valve, adjacent abscess, fibrotic scarring, or calcification
- Infected (septic) emboli from endocarditis commonly go to kidney, heart, spleen, brain
What are the microscopic pathology and common symptoms/signs of infective endocarditis?
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Microscopic pathology:
1. Fibrin, platelets, masses of organisms, +/- necrosis, +/- neutrophils
2. Later: +/- lymphos, macros, fibroblasts, fibrosis - Symptoms: fever, chills, weakness, dyspnea
- Signs: fever, heart murmur, splenomegaly, petechiae
What do you see?
- Osler nodes in fingers: tender to the touch
- Sign of infective endocarditis
What do you see?
- Splinter hemorrhage under fingernail (aka, subungual splinter hemorrhages)
- Sign for infective endocarditis, but not specific -> much more commonly due to trauma
What do you see?
- Janeway lesions: hemorrhages on palms or soles (5%)
- Sign of infective endocarditis
What do you see?
- Roth spots: retinal hemorrhages due to infective endocarditis
What tests/procedures are helpful in diagnosing infective endocarditis? Which of these is essential?
- Transthoracic echocardiography: 60% sensitivity for vegetations
1. Transesophageal echocardiography: >90% sensitive for vegetations
2. Absence of vegetations on echo does not exclude endocarditis dx - Murmur + echo + vegetations does NOT = dx -> need BLOOD CULTURES (essential for making specific dx to guide AB therapy)
1. Continuous low-grade bacteremia characteristic of infective endocarditis: 3 sites cultures, 30-60min apart before starting AB’s
2. Alert lab endocarditis suspected b/c some bac that cause endocarditis fastidious, or slow-growing, or both, so lab will use special culture media, and hold the cultures longer
What are the pluses and minuses of surgical valve replacement?
- Can be life-saving, esp. w/acute disease
- Immediate relief w/chronic disease, but replaces one chronic disease w/another -> mechanical valves require lifelong anti-coagulation
- Bioprostheses deteriorate, with structural failure in up to 50% by 10 years, accelerating after that
- Complications include: leak, thrombosis, embolism, bleeding, and endocarditis
- Critical to make sure patients understand these risks/complications from the outset
What do you see?
- Infective endocarditis: remember, fever + heart murmur = infective endocarditis (until proven otherwise)
- Mitral valve identifiable by chordae tendineae going to both leaflets (not aortic valve)
- Very large, extensive vegetations involving about 80% of leaflets (bigger the vegetations, the more likely they are infective)
- NOT mitral valve prolapse b/c many cases have valves that are microscopically normal; it is just too big. Even those with myxomatous change tend to have a normal surface -> inner zona spongiosa expanded, while outer zona fibrosa may be thinned, but is otherwise normal
- Size and extent of these very large, very extensive vegetations goes against marantic endocarditis
What is a probe-patent foramen ovale (often shortened to foramen ovale)?
- About 20% of ppl have membranous flap of tissue over foramen ovale that can be opened by pushing a probe on it
- Normally, higher pressures on left side of heart keep flap in place, maintaining separateness of left and right heart circulations
1. If pressures on right side ever rise to level higher than left, can act like probe and push open foraman ovale b/t right and left atria, letting deoxygenated blood skip passing through lungs
What are the 4 components of tetralogy of fallot?
- Ventricular septal defect (VSD)
- Overriding aorta
- Pulmonic stenosis
- RV hypertrophy
What is the most specific diagnosis you can make from this image?
- Zone of healing tissue with bluish ground substance and a few lymphs and macs
- Zone of basophilic debris (nuclear dust)
- Outer layer of condensed fibrin with scattered basophilic debris
- Central outer area of little blue dots way too small to be lymphocyte nuclei, just the right size for bacterial cocci (all bacteria are blue in H&E)
- Infective endocarditis, w/bacterial cocci: probably staph or strep, since staphy cause majority of acute bac endocarditis and strep cause majority of subacute bac endocarditis
This gross pathology most likely represents…?
- Acute rheumatic valvulitis: tiny (1-2mm) verrucous (wart-like) vegetations lined up on line of valve closure
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Differential:
1. Vegetations of infective endocarditis usually much larger
2. Vegetations of Libman-Sacks usually bigger than this (intermediate size) and rarely this numerous, nor are there features to suggest it (i.e., being on both sides of valve)
3. Marantic a strong consideration, but so many so tiny vegetations that acute rheumatic valvulitis is just slightly more likely
Briefly describe each of these.
- Rheumatic heart disease (RHD): rheumatic fever phase marked by small, warty vegetations along lines of closure of leaflets
- Infective endocarditis (IE): large, irregular masses on valve cusps that extend onto chordae
- Nonbacterial thrombotic endocarditis (NBTE): typically exhibits small, bland vegetations, usually attached at line of closure (one or many may be present)
- Libman-Sacks endocarditis (LSE): small, or medium-sized vegetations on either or both sides of valve leaflets
88-y/o hispanic male dies of a stroke, and his heart has the features in this image. The best diagnosis for this cardiac condition is…?
Infective endocarditis because it is destructive: can eat a hole in a heart valve
6 day-old boy presented to cardiology clinic with cyanosis. Born via spontaneous vaginal delivery at 37 weeks gestational age to a G1P0 mother following an uncomplicated pregnancy. Although he failed an “oxygen screen” in the hospital, he was otherwise well and was discharged to home on day 3 with instructions to follow up with the cardiology clinic. At his clinic visit, he was cyanotic w/O2 saturations in the 70s. After a chest x-ray and echocardiogram revealed congenital heart abnormalities, he was admitted to the pediatric intensive care unit.
Following surgical exploration of his heart and great vessels, a palliative procedure was performed. His chest x-ray showed a boot-shaped heart. He died on hospital day 81 and autopsy revealed the gross pathology shown. Ao = aorta, AV = aortic valve, RA = right atrium, TV = tricuspid valve, RV = right ventricle. The asterisk identifies…? What is the overall diagnosis?
- Ventricular septal defect with overriding aorta
- Tetralogy of fallot: 1) VSD, 2) overriding aorta, 3) pulmonic stenosis, 4) RV hypertrophy
This 84-year-old white male with a history of (1) hypertension (2) smoking (remote) (3) dyslipidemia (4) abdominal aortic aneurysm (5) prostate cancer presented with dyspnea on exertion. His heart had the condition shown.
What is the best diagnosis for his cardiac condition?
Calcific aortic stenosis
47-year-old white male had a history of alcohol and cocaine abuse and mitral valve prolapse. Brought to the ER nearly unresponsive with flaccid right side, fever of 40.3, pulse 136, blood pressure 189/98, respirations 30, diffuse pulmonary rhonchi and “no murmurs” specifically dictated by the admitting physician. Admission blood cultures all yielded Staphylococcus aureus. He died 36 hours later, and his heart showed the attached image. The most likely reason the admitting physician heard no murmur is…?
Inadequate physical examination
What is this?
- Mitral valve prolapse at open heart surgery
- Note the uniform color of the valve; it looks normal except for being redundant and folded up into mountains and valleys
- No vegetations are evident.
A 25-year-old East Asian male medical student has an episode of syncope at bedtime. EKG is most likely to show a diagnostic…?
- ST segment elevation -> Brugada syndrome: persistently elevated ST descending w/upward convexity to inverted T-wave (coved type; V1-V3); mostly YOUNG ASIAN MALES that present at avg age of 40 w/syncope or sudden death due to vtach, esp. DURING SLEEP
- NOT congenital QT syndrome (channelopathies) b/c present in CHILDHOOD w/syncope or sudden death due to TORSADE, triggered by EXERCISE
- NOT arrhythmogenic right ventricular cardiomyopathy (ARVC) b/c clinical presentation typically non-specific (epsilon wave notch in terminal part of QRS, QRS prolongation, T-wave inversion, etc.); most prevalent in N ITALY, and sometimes triggered by exercise
30-year-old black female engineer presents with the insidious onset of dyspnea on exertion. Her pulse is 80 and blood pressure 130/90. On cardiac auscultation, she has a high pitched sound after S2 and a diastolic rumble. Her heart has the attached image.
The complication of her cardiac condition shown by the arrow is most likely?
- Thrombus formation: any condition causing stasis of blood in the left atrium predisposes to clot formation (in this case, Rheumatic mitral stenosis is causing impaired outflow of blood from left atrium)
- Virchow’s triad: 1) endothelial injury, 2) abnormal blood flow, 3) hypercoagulability
