Term
| what is the endpoint of a lot of cardiac diseases (heart diseases, cardiomyopathies, coronary artery disease, valvular disease)? |
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Definition
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Term
| what is congestive heart failure defined as? |
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Definition
| when the heart can no longer eject blood delivered to it by the venous system |
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Term
| what pathologies can contribute to L sided CHF? |
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Definition
| HTN (increases the peripheral resistance so the left ventricle has to work harder and it becomes hypertrophied), AV, MV disease and IHD (ischemia is replaced by less functional scar tissue) |
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Term
| what pathologies can contribute to R sided CHF? |
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Definition
| L ventricular failure, cor pulmonale (R sided heart failure 2ndary to pulm disease - can be chronic/acute), and PV/TV disease |
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Term
| how does a heart affected by CHF appear morphologically? |
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Definition
| hypertrophic, dilated, and with compensated (increased HR/rx etc) or decompensated heart failure |
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Term
| what are some important features of CHF in areas other than the heart? |
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Definition
| congestion of venous circulation, pulmonary edema (heard as *rales - one of the main presentations of CHF, the higher up in the lungs - the worse), systemic venous congestion and soft tissue edema (usually in the lower extremities, presents as "pitting"), and decreased perfusion of the kidneys (which they perceive as lack of volume, and compensate by retaining more Na+ -> adds to water volume which further increases the load on the failing heart) |
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Term
| why would diuretics be a good choice in treating CHF pts? |
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Definition
| to take off some of the excess fluid built up due to the kidneys' decreased perfusion and increased fluid retention cycle |
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Term
| what are some morphologic changes associated with L sided heart failure? |
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Definition
| pulmonary congestion (blood) and edema (fluid), elevation of pulmonary venous pressure, **heart failure cells (hemosiderin laden macrophages, which is a breakdown product of hemoglobin from RBCs that are trapped and die in the alveoli), and resulting brown induration (firmness) of the lungs (fibrosis and hemosiderin deposition) |
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Term
| what are some morphologic changes associated with R sided heart failure? |
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Definition
| congestions of abdominal viscera (such as the liver), soft tissue edema, fluid in the pericardial, pleural and peritoneal cavities, chronic passive congestion, and cardiac cirrhosis (the blood vessels are congested and begin to put pressure on adjacent hepatocytes, resulting in death and fibrosis of hepatocytes, eventually leading to nodular cirrhosis) |
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Term
| how does soft tissue edema affect the way the pt sounds when auscultating their breathing? |
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Definition
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Term
| what is the fluid associated with edema? |
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Definition
| serous fluid, which is low protein and straw colored |
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Term
| what are clinical features of CHF? |
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Definition
| dyspnea, orthopnea (dyspnea/shortness of breath when lying down - due to impeded blood flow), paroxysmal nocturnal dyspnea, lung rales, and edema |
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Term
| what is a cardiomyopathy? what are common causes? |
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Definition
| heart disease resulting from a primary abnormality in the myocardium. many cases are idiopathic, though some have genetic abnormalities in cardiac energy metabolism or exposure to toxins |
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Term
| what is the most common CMP (cardiomyopathy)? least common? how common is hypertrophic CMP? |
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Definition
| most common: dilated, least common: restrictive. hypertrophic is inbetween |
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Term
| how can the cause of CMP be determined? |
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Definition
| in living pts, endomyocardial bxs cane be used to dx/manage pts. this is done by inserting a bioptome transvenously into the R side of the heart, and taking a fragment of the septal myocardium |
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Term
| how does dialated cardiomyopathy usually present? |
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Definition
| the LV and LA are typically ballooned out |
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Term
| how does hypertrophic cardiomyopathy usually present? |
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Definition
| the LV is much smaller due to impinging excessive muscle in the walls |
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Term
| how does restrictive cardiomyopathy usually present? |
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Definition
| the vessels appear normal, but are stiff, noncompliant and contract poorly. the LA may be dilated |
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Term
| what accounts for 20-50% of dilated CMPs? |
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Definition
| genetic causes such as mutations in genes that regulate the cytoskeleton of myocytes, which then leads to defects in force generation/force transmission/myocyte signaling. *genes encoding for enzymes involved in beta-oxidcation of fatty acids can also be involved |
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Term
| what is the dilated CMP phenotype? |
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Definition
| the heart is enlarged over all and various myocytes are subject to hypertrophy, dilation, fibrosis/interstitial, and infracardiac thrombi (due to prothrombotic state) |
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Term
| what are some non-genetic causes of dilated CMP? can the causes necessarily be determined? |
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Definition
| alcohol, myocarditis, idiopathic. the cause may not be able to be determined - b/c the end clinical features are the same (heart failure, sudden death, atrial fibrillation, & stroke) |
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Term
| what is the most likely cause for hypertrophic CMP? |
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Definition
| genetic mutations in sarcomeric proteins, causing a decreases energy transfer from the mitochondria to the sarcomeres |
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Term
| what is the specific phenotype for hypertrophic cardiomyopathy? |
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Definition
| a thickened L ventricle (resulting in outflow tract problems), overall enlarged heart, asymmetrical hypertrophy, myofiber disarray, fibrosis, and thickened septal vessels |
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Term
| what are the end clinical features of dilated/hypertrophic CMP? |
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Definition
| heart failure, sudden death, atrial fibrillation, and stroke |
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Term
| what are hearts affected by dilated CMP characterized by? |
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Definition
| progressive cardiac dilation and systolic dysfunction |
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Term
| how many pts w/dilated CMP have it due to genetics? what are other common causes? |
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Definition
| 25-35% of dilated CMP cases are genetic (autosomal dominant most common, x-linked less common - can be tested for w/bloodwork), the remaining may be due to myocardial insults such as; toxicities/myocarditis/pregnancy associated nutritional deficiency/immunologics |
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Term
| are mural thrombi common in dilated CMP? |
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Definition
| yes, and they can be a source of thromboemboli b/c the wall is abnormal - clot sticks on the wall and portions of it can begin to break off and enter the systemic circulation (can result in stroke, mental changes) |
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Term
| what are the components of the myocyte most affected by dilated CMP? |
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Definition
| sarcoglycan, dystrophin, lamin, desmin, titin, and mitochondrial proteins |
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Term
| what are the components of the myocyte most affected by hypertrophic CMP? |
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Definition
| myosin binding protein C, myosin light chains |
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Term
| what are the components of the myocyte most affected by hypertrophic AND dilated CMP? |
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Definition
| actin, B-myosin heavy chains, troponin, and A-tropomyosin |
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Term
| what is one of the key features of dialated cardiomyopathy in teenagers? |
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Definition
| *changes in dystrophin - the structure that helps attach the cytoskeleton of the heart muscle to the ECM (this is also seen in muscular dystrophy), this is usaully *X linked |
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Term
| what is one of the key features of dialated cardiomyopathy in children? |
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Definition
| there is usually a mutation in the gene coding for mitochondria |
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Term
| what characterizes the histologic findings for dilated CMP? |
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Definition
| they are nonspecific and do not point towards any specific etiology. the muscle cells may be hypertrophied while others are elongated, stretched and irregular (hypertrophied myocytes will take up the slack for the injured, stretched, irregular myocytes - 2 populations of cells). interstitial fibrosis and small subendothelial scars may be present due to healing of previous ischemic episodes |
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Term
| what characterizes the gross findings for dilated CMP? |
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Definition
| the heart is generally 2-3x normal weight, flabby, subject to various changes from thinning to thickening, all 4 chambers are usually dilated, coronaries are usually unremarkable (w/pure DCMP), and the heart is hypocontractile |
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Term
| what are other common gene mutations associated with dilated CMP? |
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Definition
| cardiac alpha actin, desmin, nuclear lamina proteins A & C |
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Term
| what is the most common cause of myocarditis which can then lead to dilated CMP in young pts? how can this be tested for? |
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Definition
| viral myocarditis - which can injure the myocytes to the point of becoming dilates. to test for this as a cause, viral nucleic acids (such as coxsackeivirus B) should be detectable in the myocardium, as well as some possibly recognizable characteristics of bxs |
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Term
| what is the most common cause of myocarditis which can then lead to dilated CMP in adults? |
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Definition
| alcohol (ETOH) and acetaldehyde (metabolite) may have direct toxic effects on the myocardium. chronic alcoholism may also result in a thiamine (vit B1) deficiency that introduces an element of beriberi disease |
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Term
| what is pregnancy associated dilated CMP? what can cause it? |
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Definition
| pregnancy associated dilated CMP (or peripartum CMP) occurs late in pregnancy/several weeks - months postpartum and is usually due to several factors such as HTN and nutritional deficiency. elevated levels of anti-angiogenic cleavage products from prolactin may be related |
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Term
| what is characteristic grossly of dilated cardiomyopathy? |
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Definition
| round appearance (rather than typical V shape), dilation of the chambers, some hypertrophy, thin septum near the apex |
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Term
| what is characteristic microscopically of dilated cardiomyopathy? |
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Definition
| fibrosis between myocytes (can be specifically stained for), some hypertrophied myocytes, some elongated and stretched myocytes. *interstital fibrosis is indicative for prior ischemic event, and pt w/this are more at risk for arrhythmias due to loss of contractility |
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Term
| how can dilated CMPs lead to strokes? |
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Definition
| the enlarges endocardium tends to produce thrombi that can break off -> stroke |
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Term
| what is arrhymogenic R ventricular dysplasia? |
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Definition
| an inherited disease classified as a subtype under DCMP. arrhymogenic R ventricular dysplasia causes R ventricular failure, rhythm disturbances (V tachycardia or fibrillation) and can lead to sudden death esp in young people |
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Term
| how does arrhymogenic R ventricular dysplasia appear? |
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Definition
| as a thin, fatty replacement of the R ventricle that contributes to the abnormal rhythm. fibrosis is present, and the R ventricle is about 1 mm thick and the rest is replaced by fat (should be 2-3 mm) |
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Term
| how is arrhythmogenic R ventricular dysplasia acquired? |
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Definition
| arrhythmogenic R ventricular dysplasia which is marked by a thin R ventricular wall (loss of myocytes/extensive fatty infiltration) has autosomal dominance and variable penetrance. the genetic mutation is related to defective cell adhesion proteins in the desmosomes that link adjacent cardiac myocytes |
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Term
| how would arrhythmogenic R ventricular dysplasia appear grossly/microscopically? |
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Definition
| the R ventricle is very thin, w/visible fat and fibrosis which can be stained for |
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Term
| what are clinical features of arrhythmogenic R ventricular dysplasia? |
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Definition
| it can affect wide age ranges and features dyspnea, fatigue, decompensation (if allowed to progress), and death is possible due to arrhythmia or progressive cardiac failure |
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Term
| once fibrosis occurs in the heart, is it usually reversible? |
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Definition
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Term
| what is the second most common type of CMP? |
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Definition
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Term
| what is hypertrophic CMP characterized by? can it mimic other conditions? |
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Definition
| *uniform myocardial hypertrophy, abnormal diastolic filling (heart has increased work load - pumps more w/increased heart rate, which leads to more hypertrophy – a cycle that continues - can give rise to arrhythmias/outflow obstruction (if under aorta)/sudden death), intermittent ventricular outflow obstruction, thickened, flabby, and *hypercontracting. it can mimic amyloidosis and hypertensive heart disease (w/HTN, hypertrophy is acquired) |
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Term
| might an enlarged cardiac silhouette be indicative of hypertrophic CMP? |
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Definition
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Term
| what is the major difference between dilated and hypertrophic CMP? |
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Definition
| w/hypertrophic CMP, there is massive myocardial hypertrophy - but w/out ventricular dilation. the heart is heavy, but not like the balloon shape seen w/dilated |
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Term
| what are uniquely hypertrophic CMP morphologic changes? |
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Definition
| disproportionate thickening of the ventricular septum compared to the free wall of the L ventricle (greater than 1:3, may appear banana-shaped w/bulging out). the ventricular cavity also loses its round to ovoid shape. disproportionate hypertrophy usually involves the subaortic region and there may be endocardial thickening or mural plaque formation in the L ventricular outflow tract and thickening of the mitral valve leaflet (due to rubbing) |
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Term
| what is hypertrophic CMP characterized by microscopically? |
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Definition
| extensive myocyte hypertrophy, haphazard disarray of myocytes (different from HTN-caused hypertrophy) and contractile elements in sarcomeres, and interstitial fibrosis |
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Term
| what are the genetic characteristics of hearts affected by hypertrophic CMP? what is the most common mutation? |
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Definition
| mutations are found in genes that code for the sarcomere, they are autosomal dominant genes for the cardiac troponin T, myosin binding protein, and the **beta myosin heavy chain mutation is the most commonly mutated |
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Term
| what are clinical features of hypertrophic CMP? |
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Definition
| reduced chamber size, poor compliance, reduced stroke volume, impaired diastolic filling, there may be an obstruction of ventricular outflow tract, there may be myocardial ischemia (b/c the bigger the heart, the higher the O2 demand), and atrial fibrillation/mural thrombus formation (abnormal blood flow sets up mural thrombus/shedding potential - may need to be on anticoagulant therapy) |
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Term
| what is the most common cause of sudden cardiac death in young athletes? |
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Definition
| genetically acquired HCMP |
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Term
| what is restrictive CMP? how is contractile cardiac function affected? |
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Definition
| the least common form of CMP, this is a decrease in ventricular compliance - causing impaired ventricular filling during diastole (very stiff). the contractile function of the L ventricle is unaffected |
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Term
| what are common causes for restrictive CMP? |
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Definition
| idiopathic, radiation, fibrosis, amyloidosis, sarcoidosis (non-caseating granulomas), metastasis, and inborn errors of metabolism |
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Term
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Definition
| a deposition of beta-pleated sheets (waxy material) which can be in-between myocytes and is seen systemically with multiple myeloma |
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Term
| what is the morphology of restrictive CMP characterized by? |
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Definition
| ventricles of relatively normal size, non-dilated ventricular cavities BUT **biatrial dilation is common, and patchy/diffuse interstitial fibrosis is seen |
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Term
| what is endomyocardial fibrosis? |
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Definition
| a form of restrictive CMP that is seen in children and young adults in Africa and other tropical areas. it features fibrosis of the ventricular endocardium/subendocardium that extends from the apex up, that diminishes volume/compliance of the chambers. it may involve the TCV and MV and mural thrombi may develop |
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Term
| what is loeffler's endomyocarditis? |
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Definition
| a kind of endomyocardial fibrosis associated with eosinophilic leukemia where toxic products of the eosinophils initiate endocardial damage w/necrosis and eosinophilic infiltrate. this can stimulate formation of large mural thrombi and microscopically, abnormal infiltration of eosinophils may be seen |
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Term
| what is the prognosis for pts with loefflers endocarditis? |
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Definition
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Term
| what is endocardial fibroelastosis? |
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Definition
| an uncommon focal/diffuse or fibroelastic thickening of mular L ventricular endocardium that usually happens early in life, is associated with other congenital anomalies and can result in aortic valve destruction (1/3 of cases), rapid cardiac decomposition and death |
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Term
| what kinds of dysfunction are the 3 types of CMP? |
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Definition
| dilated: systolic, hypertrophic (contractility impaired): distolic (compliance), restrictive: distolic (compliance) |
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Term
| what kind of CMP is friederich ataxia associated with? |
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Definition
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