VALVULAR HEART DISEASE Flashcards
What are the two true-ism’s about calcium?
Calcium collects in various tissues as humans age
Calcium collects in various tissues that undergo damage, injury, or necrosis
What is Calcific aortic degeneration/stenosis?
Calcific aortic degeneration is the very/most common valvular abnormality that occurs with age, as repetitive motions of the delicate valves, combined with pressure gradient phenomena on either side, act to ever so slightly breakdown, remodel, or injure the valve structure; this agerelated, ‘wear and tear’ change can be arguably viewed as a ‘normal’ physiologic aging process, although it impacts only a small percentage of peoples (2-3%).
What is common pathology seen with calcific aortic degeneration/stenosis?
- Calcific nodules (AKA: calcific degeneration) developing on valve
- Aortic valvular thickening and narrowing, with impaired function
- LVH developing as stenosis progressively increases
- Chronic heart failure or chronic ischemic heart disease can finally evolve, leading to angina, syncope, and/or CHF findings
what are two common patient profiles of calcific aortic stenosis?
- Senile calcific aortic stenosis – patients in their 70-80’s with a normal native valve
- Calcific stenosis of congenital bicuspid valve – patients in their 50-60’s
Which valves are most at risk for developing aortic stenosis? What other things are they at risk for?
a bicuspid aortic valve (BAV) has less hemodynamic and structural stability than a tricuspid valve, because often 2 leaflets are fused and have a central raphe (thickened ridge or seam). BAV’s are most at risk for developing aortic stenosis, aortic dilation/insufficiency, endocarditis, and aortic dissection.
What is mitral annular calcifications? When is it clinically evident?
This is a variant on aortic calcifications, but with mitral valve involvement by nodular calcifications (also called generically calcific degeneration).
- Patients with mitral valve prolapse are more at risk for developing symptoms (which can be regurgitation, stenosis, or arrhythmia issues)
- Heavy calcific degeneration in any individual can lead to a ring of calcified tissue that is visible on chest radiographs
what is mitral valve prolapse?
The acquisition over time of grossly ‘floppy’ or ‘ballooning’ mitral valve leaflets, which also show myxomatous degeneration microscopically.
MVP typically evolves as increasing degeneration of the valve substance occurs. Excess extracellular matrix-like proteins, such as dermatan sulfate (a type of glycosaminoglycan or mucopolysaccharide), accumulate within the valve, causing it to weaken and appear somewhat thickened; recall that mucopolysaccharides readily bind water and, when in excess, the prefix ‘myxo-‘ will be used (myxomatous degeneration, myxedema, etc.). The valve leaflets eventually become redundant and floppy, and are displaced toward the left atrium.
what are some complications of mitral valve prolapse?
- Mitral valve insufficiency that allows for systolic backflow; significant tension can cause chordae tendineae rupture
- Infective endocarditis, which can occur on any valve with structure or function issues
- Sterile thrombosis development and possible emboli, causing stroke or systemic infarction
- Arrhythmia or conduction abnormalities
female to male ratio for mitral valve prolapse? what does mitral valve prolapse show on PE? more common in?
- Female-to-male ration of 7:1
- Typically asymptomatic; symptoms more likely to appear in older patients, males, and those with other heart issues (CAD, LVH for any reason, etc.)
- Classic murmur: mid-systolic click followed by a late systolic murmur (as regurgitation occurs later in systole) • More common in Ehlers-Danlos syndrome, Marfan syndrome, polycystic kidney disease, and Graves disease
what is rheumatic fever? what is it triggered by?
Rheumatic fever (RF) is a systemic, recurrent inflammatory disease, classically occurring a few weeks later than, and triggered by, a pharyngeal infection with Group A β-hemolytic streptococci.
- Rapid diagnosis and treatment for strep pharyngitis have dramatically decreased RF and RHD is the US
- Acute and chronic cardiac involvement are well described.
what is the mechanism of rheumatic fever?
Mechanism: in genetically susceptible individuals, the infection results in production of antibodies that cross-react with cardiac antigens (type II hypersensitivity reaction), particularly antibodies and CD4+ T cells directed against streptococcal M proteins.
the acute carditis of Rheumatic fever may include?
The acute carditis of RF may include a series of inflammatory lesions involving any layer of the heart - the heart valves, endocardium, myocardium or pericardium/pericardial space. These can lead to clinical findings such as myocardial dysfunction or dilation, arrhythmia, pericardial effusions or friction rubs, or acute heart failure.
what is the classic pathology finding of Rheumatic fever? Valve leaflets may also develop?
the classic Aschoff body of RF – a collection of myocardial lymphocytes and macrophages; some references go on and on about Anitschkow cells (at arrow, maybe), which are the macrophages that may become binucleate or show chromatin changes.
• Valve leaflets can also develop verrucae composed of inflammatory cells and fibrin – an acute valvulitis.
what happens with Chronic rheumatic heart disease?
Chronic RHD doesn’t occur suddenly many years later, but slowly evolves from the acute changes above and eventually becomes clinically apparent. The delicate heart valves are most susceptible to chronic changes, and most of the long-term sequelae of RHD involves them. Valve leaflets, particularly the mitral valve, may thicken, fuse, and become stenotic; the same process can occur to the chordae tendineae.
All types of rheumatic heart disease can lead to?
All of these changes can lead to mitral stenosis, mitral regurgitation, left atrial enlargement, pulmonary vascular congestion, and right heart failure. The LV may appear fairly normal.
