Hemodynamic Disorders - 1 Flashcards
What is a hemorrhage?
extravasation of blood due to vessels rupture
What is the most common cause of brain stroke?
arterial hypertension
What is the most common site of vascular rupture in the brain?
What is the most common site of brain hemorrhage?
lenticulostriate arteries – small branches of middle cerebral artery (therefore internal capsule and adjacent basal ganglia are the most frequent site of cerebral hemorrhage).
How can we evaluate the brain hemorrhage?
depends upon its size and localization
How does the recent brain hemorrhage look like macroscopically ?
- Cerebral hemisphere is swollen, showing flattened gyri
- On cut surface blood clot can be seen surrounded by compressed edematous tissue
What are the substances that are removed by macrophages Phagocytosis In cases patient survives the brain hemorrhage ?
the blood mixed with necrotic brain mass
- RBCs; their heme is transformed into brown hemosiderin
- Cerebral lipids; accumulated in the cytoplasm which becomes foamy.
What is the result of The removal of the destroyed masses in old brain hemorrhage ?
formation of post-apopletic cavern (lacuna postapopletica) –fluid-filled pseudocyst lined with astroglial cells with hemosiderin-laden macrophages
- pseudocyst (pathologic cavity without epithelial lining)
How does old (inveterated) brain hemorrhage looks under the microscope?
the slide reveals the margin of hemorrhagic pseudocyst with hemosiderin-loaded macrophages and free hemosiderin granules derived from ingested erythrocytes
What does the term “congestion” means?
What does passive “venous” congestion means?
- increase in blood volume in dilated vessels.
- impairment of blood out flow from affected area.
What does the term “nutmeg liver” means?
Chronic passive liver congestion
What could be the causes of nutmeg liver ?
- right-sided heart failure, the most common cause.
- compression or obstruction of IVC or hepatic veins.
What is the most common cause of morphological changes in nutmeg liver?
hypoxia of hepatocytes
What is the gross appearance of nutmeg liver?
- mottled cut surface
- dark-red centrilobular areas
- pale, yellowish peripheral zones of lobules
How does the nutmeg liver looks under the microscope?
- central hepatic lobules are highly engorged by blood and
- centrilobular hepatocytes may become atrophic or necrotic
- peripheral hepatic lobules shows either normal parenchyma or fatty degeneration
What is the Pulmonary brown induration ?
Chronic passive congestion of the lungs
What are the most common causes of Pulmonary brown induration? And what does it lead to?
- as a result of long-standing, gradually developing left-sided heart failure or mitral stenosis
- may lead to fibrosis due to stimulated collagen formation
How does Pulmonary brown induration look macroscopically?
brown and firm
How does Pulmonary brown induration look under microscope?
- considerable thickening of inter-alveolar septa
- Numerous erythrocytes can be seen in alveolar spaces
- heart failure cells; intra-alveolar macrophages containing brown hemosiderin granules
- hemosiderin Deposits in interstitial pulmonary tissue.
What is the characteristics of pulmonary edema?
Fluid accumulation in the lungs
What is the classification of pulmonary edema?
- hemodynamic edema
- edema due to microvascular injury (alveolar injury)
- edema of undetermined origin
What are the causes of hemodynamic edema?
- increased hydrostatic pressure (pulmonary venous pressure)
- left-sided heart failure
- mitral stenosis
- pulmonary vein obstruction
- over-hydration - decreased oncotic pressure
- hypoalbuminemia
- liver and renal diseases - Lymphatic obstruction (rare)
What are the causes of alveolar injury edema?
- Direct
- infections: pneumoni
- inhaled gases: high concentration oxygen, smoke
- liquid aspiration: gastric contents - Indirect
- drugs and chemicals: bleomycin, heroin
- blood transfusion
- burns
What might be the causes of undetermined origin edema?
- high altitude
- CNS trauma
What is the appearance of pulmonary edema macroscopically?
lungs are enlarged, heavy and watery that fluid can be squeezed from the surface cuts
How does pulmonary edema look under the microscope?
- some RBCs and hemosiderin-laden macrophages in alveolar lumina
- empty round spaces within intra-alveolar fluid reflect frothing of edema fluid
What are the compositions of atherosclerosis?
- cells, including SMCs, macrophages, and other leukocytes;
- ECM, including collagen, elastic fibers, and proteoglycans
- intracellular and extracellular lipids
What is the structure of atherosclerosis?
- superficial fibrous cap (composed of SMCs and dense ECM)
- necrotic core, containing disorganized mass of lipid, dead cells, foam cells, fibrin, variably organized thrombus, and other plasma proteins.
What are foam cells ?
Foam cells are large, lipid-laden cells that derive predominantly from blood monocytes (tissue macrophages).
Where does atherosclerosis develop mainly?
- in elastic arteries (e.g., aorta, carotidarteries)
- in large and medium-sized muscular arteries (e.g., coronary arteries).
What are the major consequences of atherosclerosis?
- Myocardial infarction
- cerebral infarction (stroke)
- aortic aneurysms
- peripheral vascular disease
What are the non-modifiable risk factors of atherosclerosis ?
- Genetics and family history
- Aging : clinical manifestations start between 40-60
- male gender : but increase rapidly in postmenopausal women
What are the major modifiable risk factors of atherosclerosis ?
- hypercholesterolemia (increased LDL and decreased HDL)
- hypertension
- smoking
- diabetes mellitus
What are the minor risk factors of atherosclerosis?
- inflammation
- hyperhomocysteinemia
- metabolic syndrome
- factors affecting hemostasis
- obesity
What are the key processes in atherosclerosis?
intimal thickening and lipid accumulation (fatty streaks)
What are the constitutes of An atheroma or atheromatous (atherosclerotic) plaque ?
- accumulation of lipoproteins with cholesterol, phagocytized by myocytes and macrophages (yellow plaque).
- When it is covered by a firm, white fibrous cap it is (white plaque).
