Patho Exam 3
A 66-year-old man with Parkinson disease develops pleuritic chest pain. On exam, he has guarding over the right lower lung with dullness to percussion. A chest CT scan shows a focal, wedge-shaped pleural baesed area of hemorrhage in the right lower lobe. Which of the following is the most likely cause for his pulmonary lesion? A Embolism B Atherosclerosis C Vasculitis D Arteriolosclerosis E Thrombosis
(A) CORRECT. A pulmonary infarction is described. A thromboembolus from the venous circulation, usually arising in large leg veins, has lodged in a peripheral pulmonary arterial branch. The bronchial arterial supply to the lung does not provide enough oxygenation to prevent infarction, but does provide blood to make the infarct hemorrhagic. His neurodegenerative disorder with reduced movement is a risk for phlebothrombosis.
A 58-year-old woman has the sudden onset of severe dyspnea with chest pain and diaphoresis. A chest CT scan shows areas of decreased attenuation within the main pulmonary arteries. Her D-dimer assay is elevated. Her acute event is most likely to be a consequence of which of the following? A Placement of a hip prosthesis B Marked thrombocytopenia C Chronic alcoholism D Infection with the human immunodeficiency virus E Rheumatoid arthritis
(A) CORRECT. Immobilization is a major risk for the development of venous thrombosis and subsequent pulmonary embolization (the areas of diminished attenuation). Immobilization occurs following surgery. The postoperative goal: get the patient mobile as soon as possible, and meanwhile employ methods to reduce the risk for thrombosis.
A 57-year-old woman has had episodes of abdominal pain following meals for the past year. Her BMI is 31. She has hypertension. Her total serum cholesterol is increased. Which of the following types of blood vessel is the most likely location for the pathologic abnormality causing her pain? A Artery B Arteriole C Capillary D Venule E Vein
(A) CORRECT. She has abdominal angina from vascular insufficiency. She has multiple risk factors for atherosclerosis. Atherosclerosis occurs in muscular arteries, because the level of blood pressure in arteries predisposes to endothelial dysfunction.
A 63-year-old man has had increasing exercise intolerance for the past 6 years so that he now becomes short of breath upon climbing a single flight of stairs. Laboratory studies have shown fasting blood glucose measurements from 145 to 210 mg/dL for the past 25 years, but he has not sought medical treatment. If he dies suddenly, which of the following is most likely to be the immediate cause of death? A Myocardial infarction B Nodular glomerulosclerosis C Cerebral hemorrhage D Hyperosmolar coma E Right lower leg gangrene
(A) CORRECT. This is the most common cause of death in persons with diabetes mellitus, because of the high prevalence of advanced coronary atherosclerosis.
An autopsy study reveals that evidence for atheroma formation can begin even in children. The gross appearances of the aortas are recorded and compared with microscopic findings of atheroma formation. Which of the following is most likely to be the first visible gross evidence for the formation of an atheroma? A Thrombus B Fatty streak C Calcification D Hemorrhage E Exudate F Ulceration
(B) CORRECT. A fatty streak on the arterial intimal surface is the first grossly visible sign of atheroma formation. It is benign and reversible, but it may be the precursor to more severe plaques.
A study of atherogenesis is performed. There is a propensity for atheromas to form at muscular arterial branch points, such as the carotid and aortic bifurcations. Which of the following events in the arteries at these locations is most likely to initiate atherogenesis? A Collagen synthesis B Endothelial dysfunction C Lactic acidosis D Cholesterol breakdown E Hypoxemia
(B) CORRECT. A variety of stressors may affect endothelial cells, including the shear stress from turbulent flow at arterial branch points. Endothelial dysfunction is the initiating event that allows insudation of lipids to promote atherogenesis.
Following a meal, lipids are digested and absorbed. Lipids collect within enterocytes. Which of the following chemical components of the blood is mainly responsible for transporting exogenous (dietary) triglyceride from the intestine to the liver? A Apoprotein B Chylomicron C Lipoprotein lipase D Oxidized low density lipoprotein E High density lipoprotein
(B) CORRECT. Chylomicrons formed in intestinal epithelial cells contain apoproteins, triglyceride and cholesterol.
A 30-year-old man goes to his physician for a routine health checkup. On physical examination there are no abnormal findings. Laboratory test findings include serum glucose 80 mg/dL, hemoglobin A1C 4%, total cholesterol 240 mg/dL, LDL cholesterol 180 mg/dL, and HDL cholesterol 20 mg/dL. Through which of the following mechanisms is endothelial vascular injury in this patient most likely to occur? A Accumulation of sorbitol B Insudation of lipid C Inflammation with neutrophils D Deposition of immunoglobulins E Activation of complement
(B) CORRECT. He has hypercholesterolemia with more of the 'bad' LDL cholesterol that can become oxidized and taken up by modified arterial wall LDL receptors. The lipid collects in macrophages that transform to foam cells. These foam cells accumulate and becomes a lipid lesion--the precursor to more serious atheromatous plaques.
An autopsy study is conducted involving the gross appearance of the aorta of adults ranging in age from 60 to 90. In some of these patients, the aorta demonstrates atheromatous plaques covering from 70 to 95% of the intimal surface area, mainly in the abdominal portion, with ulceration and calcification. Which of the following contributing causes of death are these patients most likely to have? A Hyperparathyroidism B Hypertension C Marfan syndrome D Thrombophlebitis E Vasculitis F Colonic adenocarcinoma G Systemic lupus erythematosus
(B) CORRECT. Hypertension is a risk factor that accelerates atheromatous plaque formation.
What drugs are commonly used to treat CHF and what is the rationale for their use?
ACE Inhibitors: Decrease volume overload and decrease sodium and water retention. ARB: block angiotensin receptor binding site. B-Blocker: reduce heart rate, reduce oxygen demand on heart. Digoxin: increase contractility of the heart. This is given at later stages of CHF to help patients maintain heart function.
A 62-year-old man has experienced substernal chest pain upon exertion with increasing frequency over the past 6 months. An electrocardiogram shows features consistent with ischemic heart disease. He has a total serum cholesterol of 262 mg/dL. By angiography, there is 75% narrowing of coronary arteries. In which of the following locations is a mural thrombus most likely to occur in this man? A Left atrium B Left ventricle C Right atrium D Right ventricle E Aorta F Vena cava
(B) CORRECT. The left ventricle is the major user of oxygen and nutrients and requires a good blood supply. A complication of ischemic heart disease with infarction is development of overlying mural thrombus. Such mural thrombi are likely to result from damage to the left ventricle from ischemic heart disease, either acutely with an underlying myocardial infarction, or with a left ventricular aneurysm formed following resolution of a large myocardial infarction
A longitudinal study is conducted to detect serum markers that predict risk for death from acute coronary syndromes. A marker is identified that is synthesized and released from the liver in response to formation of cytokines in atheromatous plaques. This marker increases endothelial adhesiveness to platelets. What is this marker most likely to be? A Prostacyclin B Immunoglobulin G C C-reative protein D Alpha-1-antitrypsin E Acetoacetate
(C) CORRECT. An increased CRP predicts a greater likelihood for adverse events from atherogenesis. One benefit of 'statin' drugs is their CRP lowering effect.
A 63-year-old man has had insulin dependent diabetes mellitus for over two decades. The degree of control of his disease is indicated by the laboratory finding of hemoglobin A1C 10.1%. He has noted episodes of abdominal pain following meals. These episodes have worsened over the past year. On physical examination, there are no masses and no organomegaly of the abdomen, and he has no tenderness to palpation. Which of the following pathologic findings is most likely to be present in this man? A Ruptured aortic aneurysm B Hepatic infarction C Mesenteric artery occlusion D Acute pancreatitis E Chronic renal failure
(C) CORRECT. He has 'abdominal angina' from diminished blood flow to the bowel as a consequence of severe atherosclerosis. Persons with diabetes mellitus may have this finding, because all branches of major arteries to the bowel are affected by atherosclerosis.
A 49-year-old woman has experienced marked pain in her lower extremities on ambulation more than 300 meters for the past 5 months. On physical examination, her lower extremities are cool and pale, without swelling or erythema. No dorsalis pedis or posterior tibial pulses are palpable. Her body mass index is 32. She is a smoker. Which of the following abnormalities of the vasculature is most likely to account for these findings? A Lymphatic obstruction B Arteriolosclerosis C Atherosclerosis D Medial calcific sclerosis E Venous thrombosis
(C) CORRECT. She has claudication from severe peripheral arterial atherosclerosis, most likely from the iliac arteries down. Her major risk factor is obesity that promotes insulin resistance and diabetes mellitus that leads to atherosclerosis.
A 66-year-old woman has the sudden loss of movement on part of the left side of her body. She has smoked a pack of cigarettes a day for the past 45 years. She has vital signs including T 37.1°C, P 80/minute, RR 16/minute, and BP 160/100 mm Hg. A cerebral angiogram reveals occlusion of a branch of her middle cerebral artery. Laboratory findings include a hemoglobin A1C of 9%. Which of the following components of blood lipids is most important in contributing to her disease? A Chylomicrons B Lipoprotein lipase C Oxidized LDL D VLDL E HDL cholesterol
(C) CORRECT. She has had a 'stroke' which is most often a consequence of cerebral atherosclerosis or embolic disease from the heart as a consequence of ischemic heart disease from atherosclerosis. LDL brings cholesterol to arterial walls, and when increased LDL is present or when there is hypertension, smoking, and diabetes, there is more degradation of LDL to oxidized LDL which is taken up into arterial walls via scavenger receptors in macrophages to help form atheromas.
A 54-year-old previously healthy woman is hospitalized for pneumonia. On the 10th hospital day she is found to have swelling and tenderness of her right leg, which has developed over the past 48 hours. Raising the leg elicits pain. An ultrasound examination reveals findings suggestive of femoral vein thrombosis. Which of the following conditions is most likely to have contributed the most to the appearance of these findings? A Trousseau syndrome B Protein C deficiency C Immobilization D Pregnancy E Chronic alcohol abuse F Hypertension
(C) CORRECT. The immobilization while in hopsital would predispose to thrombosis of leg veins. This is the most common cause for deep venous thrombosis.
A 25-year-old man experiences chest pain on exercise when he attempts to climb three flights of stairs. This pain is relieved by sublingual nitroglycerin. He is 178 cm tall and weighs 101 kg. His blood pressure is 130/85 mm Hg. Laboratory studies show a total serum cholesterol of 550 mg/dL with an HDL cholesterol component of 25 mg/dL. The blood glucose is 120 mg/dL. He is worried about these findings because his brother died of a myocardial infarction at age 34. Which of the following conditions is this man most likely to have? A Diabetes mellitus, type II B Hypertensive emergency C Familial hypercholesterolemia D Cushing syndrome E Morbid obesity
(C) CORRECT. The very high cholesterol with symptoms of coronary artery disease at such a young age, coupled with the family history, are all consistent with familial hypercholesterolemia. In most persons with hypercholessterolemia from multifactorial causes, including diet and exercise patterns, the cholesterol rarely exceeds 400 mg/dL.
What role do oxidized LDLs play in the process of atherosclerosis?
Oxidized LDL further damages vascular smooth muscle and endothelial cells.
A 44-year-old woman has a family history of heart disease. Her father and mother both developed myocardial infarction and congestive heart failure as a result of occlusive coronary atherosclerosis. A dietary modification to include consumption of which of the following is most likely to reduce her risk for ischemic heart disease? A 40% of total caloric intake as fat B Increased saturated fat C Foods with cholesterol D Cold water fish oil E Fat found in beef products F Hydrogenated oils with trans-fats
(D) CORRECT. Fish oils diminish arachidonic acid metabolites and reduce platelet aggregation.
A 56-year-old reports reduced exercise tolerance over the past 5 years. In the past year he has noted chest pain after ascending a flight of stairs. He smokes 2 packs of cigarettes per day. On examination he has a blood pressure of 155/95 mm Hg. His body mass index is 30. Laboratory findings include a total serum cholesterol of 245 mg/dL with an HDL cholesterol of 22 mg/dL. Which of the following vascular abnormalities is he most likely to have? A Hyperplastic arteriolosclerosis B Lymphedema C Medial calcific sclerosis D Atherosclerosis E Deep venous thrombosis F Plexiform arteriopathy
(D) CORRECT. He has multiple risk factors for atherosclerosis, including his weight, smoking, hypertension, and high total cholesterol with low 'good' HDL cholesterol. His findings suggest coronary artery disease with risk for an acute coronary syndrome.
A 53-year-old man has the sudden onset of chest pain. He is found to have a serum troponin I of 5 ng/mL. A year later he has reduced exercise tolerance. An echocardiogram reveals an akinetic segment of left ventricle, and he has reduced cardiac output, with an ejection fraction of 25%. He then experiences a transient ischemic attack (TIA). His serum troponin I is now <0.5 ng/mL. Thrombus formation involving which of the following locations is most likely to have put him at greatest risk for the TIA? A Cerebral vein B Vertebral artery C Superior vena cava D Left ventricle E Coronary artery F Saphenous vein
(D) CORRECT. Mural thrombi can form over the damaged area of ventricular wall following myocardial infarction. This can happen acutely overlying the necrotic myocardium; it can occur remotely in a ventricular aneurysm. Portions of the mural thrombus can break off and embolize via the systemic arterial circulation to places such as the cerebral circulation.
A 45-year-old man dies suddenly and unexpectedly. The immediate cause of death is found to be a hemorrhage in the right basal ganglia region. On microscopic examination his renal artery branches have concentric endothelial cell proliferation which markedly narrows the lumen, resulting in focal ischemia and hemorrhage of the renal parenchyma. An elevation in which of the following substances in his blood is most likely to be associated with these findings? A Ammonia B Calcium C Cholesterol D Renin E Troponin I F Triglyceride G C-reactive protein
(D) CORRECT. The findings suggest hyperplastic arteriolosclerosis, which accompanies hypertensive emergency when systolic pressure is >=180 and/or diastolic pressure &>=120 mmHg along with signs of acute or ongoing end-organ damage. Reduced renal blood flow increases renin, driving hypertension.
What are the principal features (signs and symptoms) included in the clinical definition of Unstable Angina?
- Chest Pain or Pressure - Pain or pressure on back, neck, jaw, abdomen, shoulders or arms. - Sweating - Dyspnea - Nausea and vomiting - Dizziness or weakness - Fatigue
A 34-year-old previously healthy woman notes that she has bruises form on her arms and legs with just minor trauma. Physical examination reveals areas of purpura from 1 to 3 cm in size over her trunk and extremities, but no swelling, warmth, or erythema. Peripheral pulses are all palpable and full. Her blood pressure is 110/70 mm Hg. An ultrasound examination of her lower extremities with Doppler flow measurement reveals no evidence for thrombosis. Laboratory findings include serum urea nitrogen of 16 mg/dL, LDH 300 U/L, total protein 6.9 g/dL, albumin 5.3 g/dL, alkaline phosphatase 50 U/L, AST 40 U/L, and ALT 20 U/L. Which of the following additional laboratory findings is most likely to be present in this patient? A Hyperglycemia B Hypercholesterolemia C Lactic acidosis D Thrombocytopenia E Hypoprothrombinemia F Anemia
(D) CORRECT. The platelets are responsible for dealing with small leaks in small vessels. Thrombocytopenia is marked by petechiae and purpura. She does not have evidence for peripheral vascular disease, since her circulation is good. Venous thrombosis should lead to swelling and tenderness.
A 70-year-old man has noted coldness and numbness of his lower left leg, increasing over the past 4 months. He also experiences pain in this extremity when he tries walking more than the distance of half a city block. On physical examination, his dorsalis pedis, posterior tibial, and popliteal artery pulses are not palpable. Which of the following laboratory test findings is he most likely to have? A Protein S deficiency B Blood culture with Staphylococcus aureus C Decreased arterial oxygen saturation D Hyperglycemia E Hypercalcemia
(D) CORRECT. This is peripheral arterial vascular disease from severe atherosclerosis, which is promoted by diabetes mellitus. The absence of pulses defines this as an arterial process, as does the claudication (pain with exercise). Thrombophlebitis is a venous process and leads to swelling and pain in the leg, but not loss of pulses..
What are the principal features (signs and symptoms) included in the clinical definition of Myocardial Infarction?
- Intense, oppressive, excruciating chest pressure, radiation of pain to Left Arm. - Impending sense of doom - Pale Skin - Nausea, Dsypnea, Vomiting - Tachycardia - Increase/Decrease in Blood Pressure - ST-Elevation (or No ST-Elevation) - Elevated Troponin Markers
What happened to smooth muscle cells when stimulated by an injury (dysfunction) ?
- migration from media to intima - lose the capacity to contract and gain the capacity to proliferate - synthesize ECM
What are three principal components Atherosclerotic plaques have?
1- Cells: SMCs, macrophages, lymphocytes and foam cell (lipid-laden macrophages) 2- Extracellular matrix: including collagen, elastic fibers, and proteoglycans 3- Lipid: Typical atheromas contain relatively abundant lipid both intracellular and extracellular lipid .
What are the categories of atherosclerosis ?
1-stable(asymptomatic, are rich in extracellular matrix and smooth muscle cell) 2-unstable(unstable plaques are rich in macrophage and foam cells and the extracellular matrix and known as fibrous cap)
What are the common sites of Atherosclerosis?
*Abdominal aorta. *Coronary arteries. *Popliteal artery. *The internal carotid arteries. *The vessels of the circle of Willis.
What are the key pathological features and progression of CHF? Explain how the body's compensation mechanisms for a failing heart only worsen the condition?
1. Myocardial hypertrophy and remodeling result in decreased cardiac output. Cardiac remodeled and scar tissues has decreased cardiac function and an altered ionotropic function. 2. Decreased CO results in decrease Renal Blood flow activating the RAS and SNS. 3. Angiotensin II stimulates vasoconstriction and stimulates the Adrenal Gland to secrete Aldosterone. 4. Aldosterone increases sodium and water retention which increases vascular volume and venous return, thus overstimulating cardiac stretch receptors. 5. SNS innervation to blood vessels results in vasoconstriction resulting in increased vascular resistance. SNS also increases the contractility and heart rate.
What are the ways in which CO2 is transported in blood and in what proportions?
60% - Bicarbonate Buffer System 30% - Bound to Hb 10% - Physically dissolved in blood
What are the ways in which O2 is transported in blood and in what proportions?
98% bound to Hb 1.5% dissolved in plasma
What ECG changes are consistent with acute MI? Are the different ECG changes thought to correlate to location or severity of the MI?
Acute MI may present itself with ST elevation or a T-wave inversion which is a precursor to ST elevation. Different ECG changes can be correlated to location or severity of the MI.
What two ethnic/racial groups seem to be similar in their increased risk for primary hypertension?
African Americans and Asian Men
What is a fatty streak?
An accumulation of foam cells in the sub endothelial space in blood vessels
What is an embolus? What is the most common cause of an embolus? What is the major difference in terms of clinical manifestation between an embolus that originates in the venous system vs. the arterial system?
An embolus can be a blood clot or any abnormal structure found in circulation that can travel from one area to another. The most common cause of an embolus is a DVT. The major difference in clinical manifestation between venous vs arterial embolism is where they present. Arterial embolisms will typically present at the site of occlusion, whereas venous embolisms will present further from the occlusion site.
Explain how someone's PaO2 can be normal while their total blood O2 content is dangerously low. Name at least one disease state in which this can happen?
Anemia - pO2 remains unchanged. pO2 only reflects amount of oxygen physically dissolved in plasma, not bound to Hb.
How are heart failure patients clinically categorized with respect to treatment recommendations?
At risk for heart failure: A and B Heart Failure: C and D
Which of the following is most likely to be the first visible gross evidence for the formation of an atheroma? A) Thrombus B) Fatty streak C) Calcification D) Hemorrhage
B) Fatty streak
What are the differences between "Chronic Ischemic Disease" and "Acute Coronary Syndromes?"
Both Chronic Ischemic Disease and Acute Coronary Syndromes are caused by ischemia. Chronic Ischemic Disease typically manifests itself as angina: stable, variant, and silent myocardial ischemia. The plaques within the coronary vessels are typically stable, contain more protein, and less lipid. Acute Coronary Syndrome results from unstable angina and results from acute cardiac tissue death caused by a plaque that has ruptured and blocking blood flow.
What factors can alter the relationship between percent Hb saturation and pO2?
CO2, Acidity, and Temperature. Increased CO2, acidity, and temperature will cause result in Hb-saturation due to Hb dumping off oxygen to working tissues.
The most common clinical manifestation of cardiac ischemia is cardiac ischemic pain. Is cardiac ischemia always symptomatic? What are the ways in which cardiac ischemic pain manifests? What is anginal pain? Are there any gender differences with regard to expression of anginal pain?
Cardiac Ischemia is not always symptomatic. 70% of events are silent myocardial ischemia. Cardiac Ischemic Pain manifests itself as angina. Anginal pain is a type of chest pain caused by reduced blood flow to the heart. Pain can either be diffuse visceral where they feel uneasiness, discomfort, and non-localized pain, defined somatic pain which refers by dermatome, or interpretive pain. Stable angina pain can be exacerbated by predictable or non-predictable physical activity. Patients typically feel retro-sternal chest discomfort or distress. Discomfort is located outside chest, arms, shoulders, back, jaw, or epigastrum. ~20% of patients experience "warm-up" angina, but the pain generally goes away after the warm-up period.
Why is it dangerous to give a steroid or anti-inflammatory drug to individuals in the weeks following an acute MI?
Cardiac tissue heals through the inflammatory response. By taking an anti-inflammatory, you are interfering with the healing process which can result in ventricular rupture.
"Cheerios" claims to reduce cholesterol levels if eaten daily for at least a few weeks. By what mechanism is this accomplished?
Cheerios contains a substantial amount of soluble fiber. Soluble fiber has been demonstrated to inhibit the reuptake of bile salts from the small intestine. Soluble fiber binds to bile salts thus inhibiting their reuptake.
What is meant by "collateral circulation?" What causes it to develop? What impact can it have on the outcome of an acute MI?
Collateral circulation is the alternate circulation around a blocked artery by way of other smaller veins or arteries. Collateral circulation can occur during an MI and can help maintain a certain percentage of perfusion to the ischemic tissue. They could potentially reduce the infarc size and post-infarc complications.
What are the three major hypothesized categories of genetically linked physiological alterations that may lead to the development of primary hypertension?
Defects in Renal sodium homeostasis, functional vasoconstriction, and defects in vascular smooth muscle growth.
What determines the % hemoglobin saturation?
Determined by pO2 in blood.
Which part of the medullary respiratory center is responsible for driving quiet resting breathing?
Dorsal Respiratory Group
What cell types are involved in the development of atherosclerosis?
Endothelial cells secrete inflammatory mediators and platelets, monocytes and macrophages secrete radical oxygen species which oxidizes LDL.
What are the three conditions that promote thrombosis anywhere in the cardiovascular system?
Endothelial injury, increased coagulation, and decreased blood flow.
What are the major risk factors for primary hypertension?
Family history, old age, gender (males < 55, females > 74), race, increased sodium intake, diabetes, stress, smoking, obesity, alcohol, decrease dietary intake of potassium, calcium, and magnesium.
Sarah has discovered a neat trick. She first holds her breath for as long as she can and take note of that time. Next, she begins to breathe very rapidly with exaggerated exhalations for 30 seconds. Finally, she holds her breath again for as long as she can and notices that she is able to hold her breath for nearly twice as long as the first time. Briefly explain why Sarah was able to hold her breath longer the second time.
Forceful exhalations result in decreases pCO2. She is able to hold her breath longer the second time because it takes a little longer for pCO2 to build up in the blood and for her central chemoreceptors to pick up the change.
What is the chloride shift?
HCO3- ions move out of red blood cells into the plasma down a concentration gradient when RBCs are deoxygenated. To maintain the electrical balance, Cl- ions take their place. When RBCs are oxygenated, Cl- ions leaves the cell while HCO3- ions move in
What is HDL? Where does it come from? What role does it play in regulating circulating lipid levels? Why is it considered the "good" cholesterol?
HDL is a High Density Lipoprotein. It is synthesized and excreted by the liver and small intestine. It regulates lipid levels by bringing excess cholesterol back to the liver to be broken down and excreted via the scavenger pathway. It is considered the good cholesterol based on its function of controlling blood cholesterol levels.
What initiates the process of atherosclerosis?
Inflammatory mediators, increased LDL levels, HTN, and smoking
What is an LDL? What purpose does it serve? What are the possible routes of elimination for LDLs in circulation? Why are LDLs considered the "bad" cholesterol?
LDL is a Low Density Lipoprotein that contains ~50% cholesterol and responsible for delivering cholesterol to the cells. Possible routes of elimination of cholesterol include the liver where HDL brings LDL back and cholesterol is converted into bile and excreted. Other routes are degradation and phagocytosis by neutrophils and macrophages. LDLs are considered bad cholesterol because high LDL levels contribute to atherosclerosis.
The presence of LVH increases the risk of several other cardiovascular disorders/conditions. What are those conditions and how/why does LVH increase the risk for them?
LVH leads to smaller a ventricle and increased EDV filling pressure which reduces CO and HR. LVH increases the risk of ventricular arhythmias, sudden cardiac death, and death from MI and CHF.
Think of one example of a possible cause for "primary hypercholesterolemia"?
Lack of LDL receptors or deficiency in receptors.
Why does the infracted myocardium heal through fibrosis rather than by regeneration?
When myocardial tissue dies, it sets a massive inflammatory response for the heart to undergo remodeling.
What is a foam cell?
Lipid engorged macrophage. Macrophages contain receptors for LDLs. Cholesterol from the LDL is released into the macrophages and the macrophages become fatty.
What are the physical features of a plaque?
Lipid-laden cells located in the intima of the arteries. They may contain collagen, macrophages (foam cells), smooth muscle cells, endothelial cells, and lymphocytes.
What is a lipoprotein? What types of lipoprotein exist?
Lipoproteins are is a soluble protein that combine and transport fat or other lipids within the blood. There are 5 primary types of LPL: HDL, LDL, IDL, VLDL, and Chylomicrons.
Why do post MI patients have an increased risk for cardiac arythmias?
MI results in cardiac muscle ischemia causing contractile cells to depolarize. This leads to altered impulse formation and/or altered impulse formation.
Ischemic Heart Disease is an imbalance between myocardial O2 supply and O2 demand. What factors determine myocardial O2 demand? What factors determine O2 supply?
O2 Supply: Coronary Vessel Patency, Ventricular Wall Patency, Diastolic Filling Time O2 Demand: Myocardial contractility, HR, and wall stress.
What is the most common cause of MI?
Obstruction of blood flow due to plaque accumulation of rupture.
What muscular events are involved in: Quiet inhalation Forceful inhalation Passive exhalation Forceful exhalation
Quiet inhalation: External Intercostals and Diaphragm Forceful inhalation: Internal Intercostals, SCM Passive exhalation: Relaxation of External Intercostals and Diaphragm Forceful exhalation: Abdominal Muscles
What subtypes of MI exist (based on ECG changes and location of infarction)?
Right Coronary Artery Obstruction Proximal: Right Ventricle, moderate, large inferior, posterior, lateral occlusion Distal: Small, inferior occlusion Left Anterior Descending Artery Obstruction Proximal LAD: Quickly Fatal. High mortality due to proximity to the first septal perforation. Compromises perfusion to the Purkinje Fibers. Mid LAD Distal LAD: Less Common Left Circumflex Artery Obstruction: Left Ventricle, moderate to large inferior, posterior, and lateral obstruction.
What portions of the heart are perfused by the right coronary artery, the left anterior descending branch of the left coronary artery, and the left circumflex branch of the left artery?
Right Coronary Artery: Right Atrium, Right Ventricle, SA Node, and AV Node. Left Anterior Descending Branch of the Left Coronary Artery: Perfuses intraventricular septum (Bundle of His and Purkinje Fibers. Left Circumflex Branch of the Left Artery: The Posterior and lateral free walls of the left ventricle
What is ST segment depression and ST segment elevation? What patterns of ischemia are these two ECG changes associated?
ST segment depression: Demand Ischemia. We will see some ST-depression during stress testing if CAD is causing ischemia. ST segment elevation: Supply Ischemia Related to cardiac muscle injury or death due to plaque rupture and ischemia.
What is the difference between primary and secondary hypertension?
Secondary hypertension is typically secondary to another problem (renal, endocrine, neuro, hemodynamic instability). Primary HTN is considered essential or idiopathic HTN.
What factors influence the likelihood that an atherosclerotic plaque will rupture?
Stress on the cap: Tension is directly related to intraluminal pressure times radius. The increased volume of blood increases stress. Additionally, overall weakness of the plaque. Newer plaques have a tendency to rupture more frequently.
What factors determine the amount of gas transported across the alveoli and into the pulmonary capillaries?
Surface Area, Thickness of Diffusion Barrier, and Partial Pressure Gradients.
What is the LDL receptor? What role does it play in influencing circulating LDL levels?
The LDL receptor is the apoprotein. It signals to target cells regarding it's contents. LDL receptors signal cells to uptake the LDL. A deficiency or reduction in receptor function or numbers will typically result in primary hypercholesteremia.
What influence does the coronary endothelium have over the overall balance between myocardial O2 supply and O2 demand?
The coronary endothelium responds to changes in myocardial O2 supply and demand by releasing vasoactive mediators. When oxygen levels are high, the coronary vessels will constrict. When oxygen levels are low, the coronary vessels will dilate.
Kussmal breathing is characterized by very deep and rapid respirations and is often seen with severe diabetic acidosis. What sensors stimulate this type of breathing? What is the purpose of Kussmal breathing in a patient with diabetic acidosis? Would you expect the systemic arterial PCO2 of this patient to be high, low, or normal?
The initial sensors are the peripheral chemoreceptors that sense a change in Hydrogen levels. Depth and rate of breathing is controlled by the pons. The Pons will adjust rate and depth based on metabolic demands. The purpose of Kussmal breathing is respiratory compensation to metabolic acidosis. The systemic arterial pCO2 may be lower due to increased exhalation of CO2.
Why are chronic large vascular plaques not usually the cause of acute MI?
They are typically more stable
My what mechanism do the "Statin" class drugs lower cholesterol?
They block HMG-CoA reductase, the rate-limiting enzyme in cholesterol synthesis.
What is Left Ventricular Hypertrophy (LVH)? What causes it?
Thickening of the cardiac muscle in the left ventricle due to persistently elevated cardiac afterload or aortic valve stenosis.
What cell types make up the interface between the alveoli and the pulmonary capillaries? What are the functions of each?
Type 1 Alveolar Cells: Contain Air Type 2 Alveolar Cells: Secrete pulmonary surfactant Macrophages: protection Endothelial Cells: structure/support
What part of the medullary respiratory center gets recruited in forceful breathing?
Ventral Respiratory Group
What are "White Coat Hypertension" and "Masked Hypertension"? By what method can you screen someone for these conditions?
White coat hypertension occurs when an individual may have a higher than normal blood pressure in the medical environment. Masked hypertension occurs when someone may have a decreased blood pressure while in clinic. You can give them a home monitoring blood pressure unit, teach them paced respirations, and screen for anxiety.
LDL cholesterol deliver cholesterol to? a- peripheral tissues b-heart c-liver
a - peripheral tissues
Higher levels of HDL correlate with? a- increase risk VLDL b- reduced risk VLDL c-non above
b- reduced risk VLDL
Which of the following is a major, Nonmodifiable Risk factors? a-Hyperlipidemia b-Cigarette smoking c-Increasing age d- diabetes
c-Increasing age
Which of the following is a major, Potentially controllable Risk factors? a- Male gender b- Family history c- Genetic abnormalities d- Hypertension
d- Hypertension
What is the key processes in atherosclerosis ?
intimal thickening and lipid accumulation.
What do HDL "good cholesterol" do?
mobilizes cholesterol from developing and existing atheromas and transports it to the liver for excretion in the bile.
