Exam 3 Advance Patho Module 8
Match the description with the corresponding terms. _____A. Relationship among blood flow, pressure, and resistance _____B. Increased heart rate from increased volume _____C. Relationship of wall tension, intraventricular pressure, internal radius, and wall thickness _____D. Cycles of attachment, movement, and dissociation of thin filaments during the attachments of actin to myosin _____E. Length-tension relationship of cardiac muscle Poiseuille law Cross-bridge theory Frank-Starling law Laplace's law Bainbridge reflex
A. Poiseuille law D. Cross-bridge theory E. Frank-Starling law C. Laplace's law B. Bainbridge reflex
_______A. Impairs flow from left atrium to left ventricle ______ B. Impairs flow from the left ventricle ______ C. Backflow into left atrium ______ D. Backflow into right atrium ______ E. Backflow into left ventricle Aortic stenosis Aortic regurgitation Mitral stenosis Tricuspid regurgitation Mitral regurgitation
B. Aortic stenosis E. Aortic regurgitation A. Mitral stenosis D. Tricuspid regurgitation C. Mitral regurgitation
Occlusion of the left anterior descending artery during a myocardial infarction would interrupt blood supply to which structures? a. Left and right ventricles and much of the interventricular septum b. Left atrium and the lateral wall of the left ventricle c. Upper right ventricle, right marginal branch, and right ventricle to the apex d. Posterior interventricular sulcus and the smaller branches of both ventricles
a. Left and right ventricles and much of the interventricular septum The left anterior descending artery (LAD), also called the anterior interventricular artery, delivers blood to portions of the left and right ventricles and much of the interventricular septum.
Which predominantly female valvular disorder is thought to have an autosomal dominant inheritance pattern, as well as being associated with connective tissue disease? a. Mitral valve prolapse b. Tricuspid stenosis c. Tricuspid valve prolapse d. Aortic insufficiency
a. Mitral valve prolapse Mitral valve prolapse tends to be most prevalent in young women.
What is the cause of the dyspnea resulting from a thoracic aneurysm? a. Pressure on surrounding organs b. Poor oxygenation c. Formation of atherosclerotic lesions d. Impaired blood flow
a. Pressure on surrounding organ Clinical manifestations depend on the location of the aneurysm. Pressure of a thoracic aneurysm on surrounding organs cause symptoms of dysphagia (difficulty in swallowing) and dyspnea (breathlessness).
What period follows depolarization of the myocardium and represents a period during which no new cardiac potential can be propagated? a. Refractory b. Hyperpolarization c. Threshold d. Sinoatrial (SA)
a. Refractory During the refractory period, no new cardiac action potential can be initiated by a stimulus.
A patient is diagnosed with pulmonary disease and elevated pulmonary vascular resistance. Which form of heart failure may result from pulmonary disease and elevated pulmonary vascular resistance? a. Right heart failure b. Left heart failure c. Low-output failure d. High-output failure
a. Right heart failure Right heart failure is defined as the inability of the right ventricle to provide adequate blood flow into the pulmonary circulation at a normal central venous pressure.
Which cardiac chamber has the thinnest wall and why? a. The right and left atria; they are low-pressure chambers that serve as storage units and conduits for blood. b. The right and left atria; they are not directly involved in the preload, contractility, or afterload of the heart. c. The left ventricle; the mean pressure of blood coming into this ventricle is from the lung, which has a low pressure. d. The right ventricle; it pumps blood into the pulmonary capillaries, which have a lower pressure compared with the systemic circulation.
a. The right and left atria; they are low-pressure chambers that serve as storage units The two atria have the thinnest walls because they are low-pressure chambers that serve as storage units and conduits for blood that is emptied into the ventricles.
P wave
atrial depolarization
If the sinoatrial (SA) node fails, then at what rate (depolarizations per minute) can the atrioventricular (AV) node depolarize? a. 60 to 70 b. 40 to 60 c. 30 to 40 d. 10 to 20
b. 40 to 60 If the SA node is damaged, then the AV node will become the heart's pacemaker at a rate of approximately 40 to 60 spontaneous depolarizations per minute.
Pressure in the left ventricle must exceed pressure in which structure before the left ventricle can eject blood? a. Superior vena cava b. Aorta c. Inferior vena cava d. Pulmonary veins
b. Aorta Pressure in the ventricle must exceed aortic pressure before blood can be pumped out during systole.
When endothelia cells are injured, what alteration contributes to atherosclerosis? a. The release of toxic oxygen radicals that oxidize low-density lipoproteins (LDLs). b. Cells are unable to make the normal amount of vasodilating cytokines. c. Cells produce an increased amount of antithrombotic cytokines. d. Cells develop a hypersensitivity to homocysteine and lipids.
b. Cells are unable to make the normal amount of vasodilating cytokines. Injured endothelial cells become inflamed and cannot make normal amounts of antithrombotic and vasodilating cytokines.
What change in a vein supports the development of varicose veins? a. Increase in osmotic pressure b. Damage to the valves in veins c. Damage to the venous endothelium d. Increase in hydrostatic pressure
b. Damage to the valves in veins If a valve is damaged, permitting backflow, then a section of the vein is subjected to the pressure exerted by a larger volume of blood under the influence of gravity. The vein swells as it becomes engorged, and the surrounding tissue becomes edematous because increased hydrostatic pressure pushes plasma through the stretched vessel wall.
The risk of developing coronary artery disease is increased up to threefold by which factor? a. Diabetes mellitus b. Hypertension c. Obesity d. High alcohol consumption
b. Hypertension Hypertension is the only factor responsible for a twofold-to-threefold increased risk of atherosclerotic cardiovascular disease.
What is the initiating event that leads to the development of atherosclerosis? a. Release of the inflammatory cytokines b. Macrophages adhere to vessel walls. c. Injury to the endothelial cells that line the artery walls d. Release of the platelet-deprived growth factor
c. Injury to the endothelial cells that line the artery walls Atherosclerosis begins with an injury to the endothelial cells that line the arterial walls. Possible causes of endothelial injury include the common risk factors for atherosclerosis, such as smoking, hypertension, diabetes, increased levels of low-density lipoprotein (LDL), decreased levels of high-density lipoprotein (HDL), and autoimmunity.
What is the most common cardiac disorder associated with acquired immunodeficiency syndrome (AIDS) a. Cardiomyopathy b. Myocarditis c. Left heart failure d. Heart block
c. Left heart failure Pericardial effusion and left heart failure are the most common complications of human immunodeficiency virus (HIV) infection.
Which chamber of the heart endures the highest pressures? a. Right atrium b. Left atrium c. Left ventricle d. Right ventricle
c. Left ventricle Pressure is greatest in the systemic circulation, driven by the left ventricle.
Which statement is true concerning the cells' ability to synthesize cholesterol? a. Cell production of cholesterol is affected by the aging process. b. Cells produce cholesterol only when dietary fat intake is low. c. Most body cells are capable of producing cholesterol. d. Most cholesterol produced by the cells is converted to the low-density form.
c. Most body cells are capable of producing cholesterol. Although cholesterol can easily be obtained from dietary fat intake, most body cells can also manufacture cholesterol.
What is the major determinant of the resistance that blood encounters as it flows through the systemic circulation? a. Volume of blood in the systemic circulation b. Muscle layer of the metarterioles c. Muscle layer of the arterioles d. Force of ventricular contraction
c. Muscle layer of the arterioles
An individual who is demonstrating elevated levels of troponin, creatine kinase-isoenzyme MB (CK-MB), and lactic dehydrogenase (LDH) is exhibiting indicators associated with which condition? a. Myocardial ischemia b. Hypertension c. Myocardial infarction (MI) d. Coronary artery disease (CAD)
c. Myocardial infarction (MI) Cardiac troponins (troponin I and troponin T) are the most specific indicators of MI. Other biomarkers released by myocardial cells include CK-MB and LDH
What cardiac pathologic condition contributes to ventricular remodeling? a. Left ventricular hypertrophy b. Right ventricular failure c. Myocardial ischemia d. Contractile dysfunction
c. Myocardial ischemia myocardial ischemia contributes to inflammatory, immune, and neurohumoral changes that mediate a process called ventricular remodeling.
Continuous increases in left ventricular filing pressures result in which disorder? a. Mitral regurgitation b. Mitral stenosis c. Pulmonary edema d. Jugular vein distention
c. Pulmonary edema Pressure changes are important because increased left ventricular filling pressures back up into the pulmonary circulation, where they force plasma out through vessel walls, causing fluid to accumulate in lung tissues (pulmonary edema).
During the cardiac cycle, which structure directly delivers action potential to the ventricular myocardium? a. Sinoatrial (SA) node b. Atrioventricular (AV) node c. Purkinje fibers d. Bundle branches
c. Purkinje fibers Each cardiac action potential travels from the SA node to the AV node to the bundle of His (AV bundle), through the bundle branches, and finally to the Purkinje fibers and the ventricular myocardium, where the impulse is stopped. The refractory period of cells that have just been polarized prevents the impulse from reversing its path. The refractory period ensures that diastole (relaxation) will occur, thereby completing the cardiac cycle.
Which condition is a cause of acquired aortic regurgitation? a. Congenital malformation b. Cardiac failure c. Rheumatic fever d. Coronary artery disease (CAD)
c. Rheumatic fever Rheumatic heart disease, bacterial endocarditis, syphilis, hypertension, connective tissue disorders (e.g., Marfan syndrome, ankylosing spondylitis), appetite suppressing medications, trauma, or atherosclerosis can cause acquired aortic regurgitation.
The right lymphatic duct drains into which structure? a. Right subclavian artery b. Right atrium c. Right subclavian vein d. Superior vena cava
c. Right subclavian vein The right lymphatic duct drains lymph only into the right subclavian vein.
What is the process that ensures mitral and tricuspid valve closure after the ventricles are filled with blood? a. Chordae tendineae relax, which allows the valves to close. b. Increased pressure in the ventricles pushes the valves to close. c. Trabeculae carneae contract, which pulls the valves closed. d. Reduced pressure in the atria creates a negative pressure that pulls the valves closed.
b. Increased pressure in the ventricles pushes the valves to close. During ventricular relaxation, the two atrioventricular valves open and blood flows from the higher pressure atria to the relaxed ventricles. With increasing ventricular pressure, these valves close and prevent backflow into the atria as the ventricles contract.
In systolic heart failure, what effect does the renin-angiotensin-aldosterone system (RAAS) have on stroke volume? a. Increases preload and decreases afterload. b. Increases preload and increases afterload. c. Decreases preload and increases afterload. d. Decreases preload and decreases afterload.
b. Increases preload and increases afterload. Activation of the RAAS not only causes an increase in preload and afterload, but it also causes direct toxicity to the myocardium.
What enables electrical impulses to travel in a continuous cell-to-cell fashion in myocardial cells? a. Sarcolemma sclerotic plaques b. Intercalated disks c. Trabeculae carneae d. Bachmann bundles
b. Intercalated disks Only intercalated disks, thickened portions of the sarcolemma, enable electrical impulses to spread quickly in a continuous cell-to-cell (syncytial) fashion.
What term is used to identify when a cell is temporarily deprived of blood supply? a. Infarction b. Ischemia c. Necrosis d. Inflammation
b. Ischemia Coronary artery disease (CAD) can diminish the myocardial blood supply until deprivation impairs myocardial metabolism enough to cause ischemia, a local state in which the cells are temporarily deprived of blood supply.
What pathologic change occurs to the kidney's glomeruli as a result of hypertension? a. Compression of the renal tubules b. Ischemia of the tubule c. Increased pressure from within the tubule d. Obstruction of the renal tubule
b. Ischemia of the tubule In the kidney, vasoconstriction and resultant decreased renal perfusion cause tubular ischemia and Preglomerular arteriopathy.
Which substance is manufactured by the liver and primarily contains cholesterol and protein? a. Very low-density lipoproteins (VLDLs) b. Low-density lipoproteins (LDLs) c. High-density lipoproteins (HDLs) d. Triglycerides
b. Low-density lipoproteins (LDLs) A series of chemical reactions in the liver results in the production of several lipoproteins that vary in density and function. These include VLDLs, primarily triglycerides and protein; LDLs, mostly cholesterol and protein; and HDLs, mainly phospholipids and protein. LDLs are the only lipoproteins that are manufactured by the liver and primarily contain cholesterol and protein.
Superior vena cava syndrome is a result of a progressive increase of which process? a. Inflammation b. Occlusion c. Distention d. Sclerosis
b. Occlusion Superior vena cava syndrome (SVCS) is a progressive occlusion of the superior vena cava (SVC) that leads to venous distention in the upper extremities and head.
The resting heart rate in a healthy person is primarily under the control of which nervous system? a. Sympathetic b. Parasympathetic c. Somatic d. Spinal
b. Parasympathetic The resting heart rate in healthy individuals is primarily under the control of parasympathetic stimulation.
Oxygenated blood flows through which vessel? a. Superior vena cava b. Pulmonary veins c. Pulmonary artery d. Coronary veins
b. Pulmonary veins Only the four pulmonary veins, two from the right lung and two from the left lung, carry oxygenated blood from the lungs to the left side of the heart.
Which complex (wave) represents the sum of all ventricular muscle cell depolarizations? a. PRS b. QRS c. QT interval d. P
b. QRS Only the QRS complex represents the sum of all ventricular muscle cell depolarizations.
What causes depolarization of a cardiac muscle cell to occur? a. Decrease in the permeability of the cell membrane to potassium b. Rapid movement of sodium into the cell c. Decrease in the movement of sodium out of the cell d. Rapid movement of calcium out of the cell
b. Rapid movement of sodium into the cell Phase 0 consists of depolarization, which lasts 1 to 2 milliseconds (ms) and represents rapid sodium entry into the cell.
What is the expected electrocardiogram pattern when a thrombus in a coronary artery permanently lodges in the vessel and the infarction extends through the myocardium from the endocardium to the epicardium? a. Prolonged QT interval b. ST elevation myocardial infarction (STEMI) c. ST depression myocardial infarction (STDMI) d. Non-ST elevation myocardial infarction (non-STEMI)
b. ST elevation myocardial infarction (STEMI) Individuals with this pattern on an ECG usually have significant elevations in the ST segments and are categorized as having STEMI.
Regarding the heart's valves, what is a function of the papillary muscles? a. The papillary muscles close the semilunar valve. b. These muscles prevent backward expulsion of the atrioventricular valve. c. They close the atrioventricular valve. d. The papillary muscles open the semilunar valve.
b. These muscles prevent backward expulsion of the atrioventricular valve. The papillary muscles are extensions of the myocardium that pull the cusps together and downward at the onset of ventricular contraction, thus preventing their backward expulsion into the atria.
As stated in the Frank-Starling law, a direct relationship exists between the _____ of the blood in the heart at the end of diastole and the _____ of contraction during the next systole. a. Pressure; force b. Volume; strength c. Viscosity; force d. Viscosity; strength
b. Volume; strength As stated in the Frank-Starling law, the volume of blood in the heart at the end of diastole (the length of its muscle fibers) is directly related to the force (strength) of contraction during the next systole.
Cardiac cells can withstand ischemic conditions and still return to a viable state for how many minutes? a. 10 b. 15 c. 20 d. 25
c. 20 Cardiac cells remain viable for approximately 20 minutes under ischemic conditions. If blood flow is restored, then aerobic metabolism resumes, contractility is restored, and cellular repair begins.
What is the most important negative inotropic agent? a. Norepinephrine b. Epinephrine c. Acetylcholine d. Dopamine
c. Acetylcholine Chemicals affecting contractility are called inotropic agents. The most important negative inotropic agent is acetylcholine released from the vagus nerve. The most important positive inotropic agents produced by the body are norepinephrine released from the sympathetic nerves that supply the heart and epinephrine released by the adrenal cortex. Other positive inotropes include thyroid hormone and dopamine. Many medications have positive or negative inotropic properties that can have profound effects on cardiac function.
What effect does atherosclerosis have on the development of an aneurysm? a. Atherosclerosis causes ischemia of the intima. b. It increases nitric oxide. c. Atherosclerosis erodes the vessel wall. d. It obstructs the vessel.
c. Atherosclerosis erodes the vessel wall. Atherosclerosis is a common cause of aneurysms because plaque formation erodes the vessel wall.
n the normal electrocardiogram, what does the PR interval represent? a. Atrial depolarization b. Ventricular depolarization c. Atrial activation to onset of ventricular activity d. Electrical systole of the ventricles
c. Atrial activation to onset of ventricular activity The PR interval is a measure of time from the onset of atrial activation to the onset of ventricular activation; it normally ranges from 0.12 to 0.20 second. The PR interval represents the time necessary to travel from the sinus node through the atrium, the atrioventricular (AV) node, and the His-Purkinje system to activate ventricular myocardial cells.
What is the most common cause of infective endocarditis? a. Virus b. Fungus c. Bacterium d. Rickettsiae
c. Bacterium Infective endocarditis is a general term used to describe infection and inflammation of the endocardium—especially the cardiac valves. Bacteria are the most common cause of infective endocarditis, especially streptococci, staphylococci, or enterococci.
Which event occurs during phase 1 of the normal myocardial cell depolarization and repolarization? a. Repolarization when potassium moves out of the cells b. Repolarization when sodium rapidly enters into the cells c. Early repolarization when sodium slowly enters the cells d. Early repolarization when calcium slowly enters the cells
c. Early repolarization when sodium slowly enters the cells Phase 1 is early repolarization and the only time during which calcium slowly enters the cell.
Which function of the cardiovascular system is often affected by ischemia? a. Cardiac output (CO) b. Stroke volume (SV) c. Heart rate (HR) d. Cardiac index (CI)
c. Heart rate (HR) Common causes of an abnormal heart rate include ischemia, electrolyte imbalance, and drug toxicity.
Which elevated value may be protective of the development of atherosclerosis? a. Very low-density lipoproteins (VLDLs) b. Low-density lipoproteins (LDLs) c. High-density lipoproteins (HDLs) d. Triglycerides
c. High-density lipoproteins (HDLs) Low levels of HDL cholesterol are also a strong indicator of coronary risk, whereas high levels of HDLs may be more protective for the development of atherosclerosis than low levels of LDLs.
Which statement best describes Raynaud disease? a. Inflammatory disorder of small- and medium-size arteries in the feet and sometimes in the hands b. Neoplastic disorder of the lining of the arteries and veins of the upper extremities c. Vasospastic disorder of the small arteries and arterioles of the fingers and, less commonly, of the toes d. Autoimmune disorder of the large arteries and veins of the upper and lower extremities
c. Vasospastic disorder of the small arteries and arterioles of the fingers and, less commonly, of the toes Attacks of vasospasm in the small arteries and arterioles of the fingers and, less commonly, of the toes characterize Raynaud phenomenon and Raynaud disease
A patient reports sudden onset of severe chest pain that radiates to the back and worsens with respiratory movement and when lying down. These clinical manifestations describe: a. Myocardial infarction (MI) b. Pericardial effusion c. Restrictive pericarditis d. Acute pericarditis
d. Acute pericarditis
Which assessment findings are clinical manifestations of aortic stenosis? (Select all that apply.) a. Jugular vein distention b. Bounding pulses c. Hypotension d. Angina e. Syncope
d. Angina e. Syncope The classic manifestations of aortic stenosis are angina, syncope, and heart failure.
During the cardiac cycle, why do the aortic and pulmonic valves close after the ventricles relax? a. Papillary muscles relax, which allows the valves to close. b. Chordae tendineae contract, which pulls the valves closed. c. Reduced pressure in the ventricles creates a negative pressure, which pulls the valves closed. d. Blood fills the cusps of the valves and causes the edges to merge, closing the valves.
d. Blood fills the cusps of the valves and causes the edges to merge, closing the valves. When the ventricles relax, blood fills the cusps and causes their free edges to meet in the middle of the vessel, closing the valve and preventing any backflow.
The cardiac electrical impulse normally begins spontaneously in the sinoatrial (SA) node because it: a. Has a superior location in the right atrium. b. Is the only area of the heart capable of spontaneous depolarization. c. Has rich sympathetic innervation via the vagus nerve. d. Depolarizes more rapidly than other automatic cells of the heart.
d. Depolarizes more rapidly than other automatic cells of the heart. The electrical impulse normally begins in the SA node because its cells depolarize more rapidly than other automatic cells.
The pulsus paradoxus that occurs as a result of pericardial effusion is caused by a dysfunction in which mechanism? a. Diastolic filling pressures of the right ventricle and reduction of blood volume in both ventricles b. Blood ejected from the right atrium and reduction of blood volume in the right ventricle c. Blood ejected from the left atrium and reduction of blood volume in the left ventricle d. Diastolic filling pressures of the left ventricle and reduction of blood volume in all four heart chambers.
d. Diastolic filling pressures of the left ventricle and reduction of blood volume in all four heart chambers.
Nicotine increases atherosclerosis by the release of which neurotransmitter? a. Histamine b. Nitric oxide c. Angiotensin II d. Epinephrine
d. Epinephrine Nicotine stimulates the release of catecholamines (e.g., epinephrine, norepinephrine), which increases the heart rate and causes peripheral vascular constriction. As a result, blood pressure increases, as do both cardiac workload and oxygen demand.
When the volume of blood in the ventricle at the end of diastole increases, the force of the myocardial contraction during the next systole will also increase, which is an example of which law or theory about the heart? a. Laplace's law b. Poiseuille law c. Cross-bridge theory d. Frank-Starling law
d. Frank-Starling law
Occlusion of the circumflex artery during a myocardial infarction would interrupt blood supply to which area? a. Left and right ventricles and much of the interventricular septum b. Posterior interventricular sulcus and the smaller branches of both ventricles c. Upper right ventricle, right marginal branch, and right ventricle to the apex d. Left atrium and the lateral wall of the left ventricle
d. Left atrium and the lateral wall of the left ventricle The circumflex artery supplies blood to the left atrium and the lateral wall of the left ventricle.
What physical sign is the result of turbulent blood flow through a vessel? a. Increased blood pressure during periods of stress b. Bounding pulse felt on palpation c. Cyanosis observed on excretion d. Murmur heard on auscultation
d. Murmur heard on auscultation Where flow is obstructed, the vessel turns or blood flows over rough surfaces. The flow becomes turbulent with whorls or eddy currents that produce noise, causing a murmur to be heard on auscultation, such as occurs during blood pressure measurement with a sphygomanometer.
What is the trigger for angina pectoris? a. Atherosclerotic lesions b. Hyperlipidemia c. Myocardial necrosis d. Myocardial ischemia
d. Myocardial ischemia Angina pectoris is chest pain caused by myocardial ischemia.
Which phase of the normal myocardial cell depolarization and repolarization correlates with diastole? a. Phase 1 b. Phase 2 c. Phase 3 d. Phase 4
d. Phase 4 Potassium is moved out of the cell during phase 3, with a return to resting membrane potential only in phase 4. The time between action potentials corresponds to diastole.
What is the effect of epinephrine on b3 receptors on the heart? a. Decreases coronary blood flow. b.Supplements the effects of both b1 and b2 receptors. c. Increases the strength of myocardial contraction. d. Prevents overstimulation of the heart by the sympathetic nervous system.
d. Prevents overstimulation of the heart by the sympathetic nervous system. b3 receptors are found in the myocardium and coronary vessels. In the heart, stimulation of these receptors opposes the effects of b1- and b2-receptor stimulation and negative inotropic effect. Thus b3 receptors may provide a safety mechanism that decreases myocardial contractility to prevent overstimulation of the heart by the sympathetic nervous system.
Which form of angina occurs most often during sleep as a result of vasospasms of one or more coronary arteries? a. Unstable b. Stable c. Silent d. Prinzmetal
d. Prinzmetal Prinzmetal angina (also called variant angina) is chest pain attributable to transient ischemia of the myocardium that occurs unpredictably and almost exclusively at rest.
QRS complex
ventricular depolarization
ST interval
ventricular myocardium depolarized
QT interval
"Electrical systole" of the ventricles
PR interval
Time from the onset of atrial activation to the onset of ventricular activation
What factors contribute to the development of orthostatic hypotension? (Select all that apply.) a. Altered body chemistry b. Drug action of certain antihypertensive agents c. Prolonged immobility d. Effects of aging on postural reflexes e. Any condition that produces volume overload
a. Altered body chemistry b. Drug action of certain antihypertensive agents c. Prolonged immobility d. Effects of aging on postural reflexes
Which factor can trigger an immune response in the bloodstream that may result in an embolus? a. Amniotic fluid b. Fat c. Bacteria d. Air
a. Amniotic fluid only amniotic fluid displaces blood, thereby reducing oxygen, nutrients, and waste exchange;
What is an expected change in the cardiovascular system that occurs with aging? a. Arterial stiffening b. Decreased left ventricular wall tension c. Decreased aortic wall thickness d. Arteriosclerosis
a. Arterial stiffening Arterial stiffening occurs with aging even in the absence of clinical hypertension.
The Bainbridge reflex is thought to be initiated by sensory neurons in which cardiac location? a. Atria b. Aorta c. Sinoatrial (SA) node d. Ventricles
a. Atria The Bainbridge reflex causes changes in the heart rate after intravenous infusions of blood or other fluid.
How does angiotensin II increase the workload of the heart after a myocardial infarction (MI)? a. By increasing the peripheral vasoconstriction b. By causing dysrhythmias as a result of hyperkalemia c. By reducing the contractility of the myocardium d. By stimulating the sympathetic nervous system
a. By increasing the peripheral vasoconstriction Angiotensin II is released during myocardial ischemia and contributes to the pathogenesis of a myocardial infarction (MI) in several ways. First, it results in the systemic effects of peripheral vasoconstriction and fluid retention. These homeostatic responses are counterproductive in that they increase myocardial work and thus exacerbate the effects of the loss of myocyte contractility. Angiotensin II is also locally released, where it is a growth factor for vascular smooth muscle cells, myocytes, and cardiac fibroblasts; promotes catecholamine release; and causes coronary artery spasm.
Ventricular dilation and grossly impaired systolic function, leading to dilated heart failure, characterize which form of cardiomyopathy? a. Congestive b. Hypertrophic c. Septal d. Dystrophic
a. Congestive Only dilated cardiomyopathy (congestive cardiomyopathy) is characterized by ventricular dilation and grossly impaired systolic function, leading to dilated heart failure.
What is the usual source of pulmonary emboli? a. Deep venous thrombosis b. Endocarditis c. Valvular disease d. Left heart failure
a. Deep venous thrombosis Pulmonary emboli originate in the venous circulation (mostly from the deep veins of the legs) or in the right heart.
Which risk factor is associated with coronary artery disease (CAD) because of its relationship with the alteration of hepatic lipoprotein? a. Diabetes mellitus b. Hypertension c. Obesity d. High alcohol consumption
a. Diabetes mellitus diabetes mellitus is associated with CAD because of the resulting alteration of hepatic lipoprotein synthesis; it increases triglyceride levels and is involved in low-density lipoprotein oxidation.
Which statements are true regarding fatty streaks? (Select all that apply.) a. Fatty streaks progressively damage vessel walls. b. Fatty streaks are capable of producing toxic oxygen radials. c. When present, inflammatory changes occur to the vessel walls. d. Oxidized low-density lipoproteins (LDLs) are involved in their formation. e. Fatty streaks are formed by killer T cells filled with oxidized LDLs.
a. Fatty streaks progressively damage vessel walls. b. Fatty streaks are capable of producing toxic oxygen radials. c. When present, inflammatory changes occur to the vessel walls. d. Oxidized low-density lipoproteins (LDLs) are involved in their formation.
Within a physiologic range, what does an increase in left ventricular end-diastolic volume (preload) result in? a. Increase in force of contraction b. Decrease in refractory time c. Increase in afterload d. Decrease in repolarization
a. Increase in force of contraction This concept is expressed in the Frank-Starling law; the cardiac muscle, like other muscles, increases its strength of contraction when it is stretched.
Which statement best describes thromboangiitis obliterans (Buerger disease)? a. Inflammatory disorder of small- and medium-size arteries in the feet and sometimes in the hands b. Vasospastic disorder of the small arteries and arterioles of the fingers and, less commonly, of the toes c. Autoimmune disorder of the large arteries and veins of the upper and lower extremities d. Neoplastic disorder of the lining of the arteries and veins of the upper extremities
a. Inflammatory disorder of small- and medium-size arteries in the feet and sometimes in the hands Buerger disease is an inflammatory disease of the peripheral arteries. Inflammation, thrombus formation, and vasospasm can eventually occlude and obliterate portions of small- and medium-size arteries.
What is the effect of oxidized low-density lipoproteins (LDLs) in atherosclerosis? a. LDLs cause smooth muscle proliferation. b. LDLs cause regression of atherosclerotic plaques. c. LDLs increase levels of inflammatory cytokines. d. LDLs direct macrophages to the site in the endothelium.
a. LDLs cause smooth muscle proliferation. Oxidized LDLs are toxic to endothelial cells, cause smooth muscle proliferation, and activate further immune and inflammatory responses.
