CV System Pathology 1 Flashcards
What are the two types of hemorrhage?
Acute, sudden, massive loss of blood
Chronic - low-grade, mild leakage of blood
What are some of the complications of hemorrhage?
(1) Hemorrhagic shock, which occurs when more than 15% of blood volume is lost.
(2) Hemorrhagic strokes, hemopericardium in areas sensitive to hemorrhage.
(3) Iron deficiency from chronic blood loss.
What is an exudate?
Edema fluid containing high amounts of protein and inflammatory cells
What is a transudate?
Edema fluid with a low protein content, not usually associated with inflammation
Edema due to reduced plasma osmotic pressure can be due to what?
Generally this is due to a loss of albumin. For example, nephrotic syndrome and cirrhosis can both lead to low albumin levels and thus edema
Impaired lymphatic drainage leads to what type of edema?
Lymphedema
What mechanisms are involved in compensated, early, nonprogressive shock?
(1) Increased heart rate and peripheral resistance to increase blood flow to vital organs
(2) Increased respiratory rate to remove carbon dioxide and raise pH
What occurs in the body during decompensated, progressive shock?
(1) Oxygen levels fall, causing vasodilation and decreased blood flow to the heart
(2) Cell injury and cell death occurs from lack of oxygen
What occurs in the body during the irreversible stage of shock?
(1) Acute tubular necrosis occurs in the kidney, which is initially reversible
(2) Full renal failure occurs as acute tubular necrosis becomes more severe
(3) Metabolic acidosis, coma and heart failure develop
What initiates clot (thrombus) formation?
Damage to endothelial cells that causes interactions between platelets, exposed collagen, and blood proteins.
What is the name of the factor that causes platelets to adhere to the exposed subendothelial surface in clot formation?
von Willebrand’s factor
The extrinsic coagulation pathway is initiated by what tissue factor?
Thromboplastin. Extrinsic pathway is activated by external trauma that causes blood to escape from the vessel. Intrinsic pathway is activated by trauma within the vessel.
What causes thrombosis?
Abnormalities within the body that cause damage to endothelial cells, promote coagulation, or disturb blood flow. Thrombosis is a local clot within a blood vessel.
What are the symptoms of chronic deep venous insufficiency in the legs?
Pigmentation, edema, skin induration, ulceration
What is the most common cause of death in Western industrialized countries?
Arterial thrombosis (atherosclerosis) due primarily to cigarette smoking
What is an embolus?
A piece of a thrombus that has broken off, entered the bloodstream, and become trapped in the vasculature (thromboembolism)
Where do leg venous thrombi commonly lodge?
In the lung, after entering the right atrium of the heart through the inferior vena cava and passing through the ventricle (pulmonary emboli)
Where do arterial emboli that break off from mural thrombi in the heart or major arteries commonly lodge?
(1) Branches of the carotid artery, causing stroke
(2) Branches of the mesenteric artery, causing hemorrhagic infarction
(3) Branches of the renal artery, causing renal cortex infarcts
What is the name of an embolus that lodges at the bifurcation of the main pulmonary artery?
Saddle embolus
What are the two types of infarcts?
(1) Anemic - white or pale in areas without collateral blood supply
(2) Hemorrhagic - red, in areas where collateral blood supply may be insufficient
What causes infarction?
Blockage or lack of blood flow to an organ
What is the primary pathological condition that leads to cardiac tamponade?
Pericardial effusion (which is fluid accumulation in the pericardial cavity and thus puts pressure onto the heart and affect its function).
How is arteriosclerosis defined?
Sclerosis of the arteries. Sclerosis means to harden.
What types of arteries are affected by atherosclerosis?
Atherosclerosis is arteriosclerosis of large elastic arteries, including the aorta, coronary, common iliac, femoral, popliteal, internal carotid, and cerebral arteries
What are atheromas?
Lesions that develop on artery walls comprised of macrophages, low-density lipoprotein (ldl), fibrin, and smooth muscle. They are usually asymptomatic for 20-40 years until they become symptomatic, complicated plaques
How does arteriosclerosis most probably begin?
Damage to vascular endothelium’s intima layer. This leads to plaque buildup and thus vessel hardening.
During starvation and poorly controlled diabetes, what form of fuel can the heart use?
Ketone bodies. Ketones can be used in the TCA cycle to generate ATP.
When oxidized lipids are ingested by macrophages, what do they form?
Foam cells. Foam cells are particularly indicative of early atherosclerosis formation.
What stages are involved in polyarteritis nodosa (pan)?
(1) Immune complex deposits in walls of arteries in the first stage, initiating the complement cascade and calling in neutrophils
(2) Macrophages and fibroblasts replace neutrophils in the healing stage, and fibrosis occurs
(3) In the last stage, a cord of collagen forms in the vessel with calcium deposits, occluding the lumen