Valve Diseases Flashcards
Mitral valve prolapse
Primary = CT genetic defect; Secondary = damage by injury.
Microscopic: sometimes will see degeneration of the outer zona fibrosa/atrialis, sometimes expanded myxoid substance (middle layer, but such expansion can be normal)
Gross: billowy valve leaflets, uniform color except redundant tissue
Hear: midsystolic click
*Pregnancy can cause MVP relapse because of increased BV and compensatory ventricular dilation
Infective endocarditis
Mitral valve is most commonly first infected because it has the highest pressure
Staph and strep are most common agents.
Get vegetations on the valve (highest pressure side) which are friable and can embolize.
vegetation
friable masses of infecting organism and clot
Infective endocarditis
Get vegetations on the valve (highest pressure side) which are friable and can embolize (to kidneys most common); they are large (up to 3cm) and the bigger they are the more likely infected. Vegetations/disease are destructive and severely damage the valve with scarring/calcification/abscess/perforation.
Mitral valve is most commonly first infected because it has the highest pressure.
Staph and strep are most common agents.
Fever, heart murmur, elevated ESR, anemia are most common findings. Weird findings are Osler nodes (tender, in finger/toes), splinter hemorrhages/petechiae, hemorrhages in other small weird places.
Diagnosis: TEE to see vegetations, but clincher is cultures - must do 3 and tell the lab you suspect endocarditis.
Libman-Sacks Endocarditis
Valve disease that comes with lupus; vegetations form on either or both sides of valve (weird) and they rarely embolize (also weird). Microscopically appear with lots of necrotizing, fibrinoid material, and dying cells (WBCs and fibroblasts).
Patent Foramen Ovale
open connection between the R atrium and L atrium, may be kept closed by high LA pressures but if RA pressure becomes higher it will reopen, leading to blood mixing
Tetralogy of Fallot - 4 features
- overriding aorta
- VSD
- pulmonary stenosis
- RVH
Congenital Heart Disease: Cyanotic vs. Acyanotic
cyanotic - blood leaves LV without going through lungs; mostly all start with T except for “hypoplastic left heart”
acyanotic - results in mixing of blood because of a small connection between R and L heart such that most blood is oxygenated in lungs but not all
ABE vs. SBE
ABE = acute bacterial endocarditis, most commonly due to staph aureus, a highly virulent organism; infectious onset over days. SBE = subacute bacterial endocarditis, most commonly due to viridans group strep and less virulent bugs; insidious onset over weeks/months.
4 steps of developing infective endocarditis
- endothelial injury/damage (even just due to age)
- platelet/thrombin formation
- microbial seeding
- microbial multiplication
Mitral valve with “fused and shortened chordae tendinae” is indicative of
Rheumatic heart disease (common to get valve thrombus formation because RHD causes mitral stenosis, Virchow’s triad)
*But remember, RHD is not that common in the US (whereas mitral valve prolapse affects 2% of americans, and therefore is the more common cause of infective endocarditis)
Carcinoid heart disease
refers to the cardiac manifestations of carcinoid syndrome (which is when a tumor releases bioactive compounds like Serotonin) amidst the systemic manifestations. CHD includes endocardium and RH valves damage, plauqelike thickenings that are white, distinctive, and glistening - made of smooth muscle and some collagen embedded in matrix.
Relationship between mitral valve prolapse and infective endocarditis
mitral valve prolapse can cause the injury needed for seeding of infection. However, IE is a rare complication of MVP. But MVP can be a common underlying cause of IE only because MVP is common (more common than RHD).
Septic emboli
These are emboli from infective endocarditis vegetations that spread the infection to other parts of the body - most common embolization locations are kidney, heart, spleen, brain. When they land there the emboli cause infection which creates abscesses; must drain or remove organ (kidney/spleen). Look for this complication if patient initially gets better on abx treatment and then gets another fever few days later.
vegetation (bacterial)
friable masses of infecting organism and clot
