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Left ventricular end-diastolic pressure b.. Left ventricular mean systolic pressure c?. During a routine physical examination, a 32-year-old woman is found to have second-degree heart bl

231 A 56-year-old woman presents for her annual physical examination Her physician auscultates a late systolic crescendo murmur with a midsystolic click The

murmur is best heard over the apex, is loudest at S2, is shortened with squatting, and is longer and more intense when venous return is decreased by standing or aValsalva maneuver Which of the following values is the best index of the preload on her heart?

a Blood volume

b Central venous pressure

c Pulmonary capillary wedge pressure

d Ventricular end-diastolic pressure

e Ventricular end-diastolic volume

232 A patient presents to the emergency department with intermittent chest pain The ECG and blood tests are negative for myocardial infarction, but the

echocardiogram shows thickening of the left ventricular muscle and narrowing of the aortic valve An afterload-reducing medication is prescribed Which of thefollowing values would provide the best measure of the effectiveness of the medication in reducing left ventricular afterload in aortic stenosis?

a Left ventricular end-diastolic pressure

b Left ventricular mean systolic pressure

c M ean arterial blood pressure

d Pulmonary capillary wedge pressure

e Total peripheral resistance

233 The phases of the ventricular muscle action potential are represented by the lettered points on the diagram below At which point on the ventricular action

potential is membrane potential most dependent on calcium permeability?

234 During a routine physical examination, a 32-year-old woman is found to have second-degree heart block Which of the following ECG recordings is consistent

with her diagnosis?

235 The spouse of a 58-year-old man calls 911 because her husband complains of chest pain radiating down his left arm He is transported to the emergency

department, where an ECG and cardiac enzymes indicate a recent myocardial infarction The man undergoes cardiac catheterization, including coronary angiographyand hemodynamic recordings throughout the cardiac cycle No valvular defects were present During ventricular ejection, the pressure difference smallest in magnitude

is between which of the following?

a Aorta and capillaries

b Left atrium and left ventricle

c Left ventricle and aorta

d Pulmonary artery and left atrium

e Right atrium and right ventricle

236 A 55-year-old man reports several episodes of syncope and worsening exercise intolerance over the past year Of the following, which is the most likely

diagnosis?

a Sinus arrhythmia

b First-degree heart block

c Second-degree heart block

d Third-degree heart block

e M ultifocal atrial tachycardia

237 In the hemodynamic pressure tracings below, rapid ventricular filling begins at which point?

238 An 82-year-old woman was admitted to the hospital with ascites, peripheral edema, and shortness of breath Cardiac catheterization was conducted and the

following values were obtained:

Pulmonary vein O2 content = 20 mL O2/100 mL blood

Pulmonary artery O2 content = 12 mL O2/100 mL blood

Oxygen consumption (VO2) = 280 mL/min

239 A 66-year-old man is referred to a cardiologist for evaluation Physical examination reveals a diastolic murmur prominent over the left sternal border, a decrease in

diastolic pressure, and an increase in pulse pressure Of the following, which is the most likely diagnosis?

240 The following six-lead frontal ECG was performed as part of an annual heath maintenance physical examination Which of the following is the mean electrical axis

(M EA) of the patient?

241 A patient undergoes cardiac transplantation for severe idiopathic cardiomyopathy Upon release from the hospital, the patient is referred to a cardiac

rehabilitation program The exercise physiologist starts the patient on a walking regimen During exercise in cardiac transplant patients, cardiac output increasesprimarily due to an increase in which of the following?

a Arterial blood pressure

b Heart rate

c Stroke volume

d TPR

e Venous compliance

242 A patient complaining of an irregular heartbeat is referred for a cardiac electrophysiological study Propagation of the action potential through the heart is fastest

in which of the following cardiac structures?

243 A 75-year-old woman presents with fatigue and orthopnea Rales are heard widely over both lung fields After several days of furosemide to treat the patient’s

fluid retention, lisinopril therapy is initiated Which of the following is primarily responsible for the improvement in her condition with lisinopril?

a An increase in cardiac contractility

b An increase in ventricular end-diastolic pressure

c An increase in ventricular wall thickness

d A reduction in heart rate

e Stabilization of cardiac remodeling

244 A 37-year-old woman undergoes a CT scan of the abdomen, which reveals a large peritoneal mass A subsequent magnetic resonance angiography study showed

that the abdominal aorta was constricted to one-half of its resting diameter As a result, resistance to blood flow through the vessel would be which of the following?

245 A patient undergoes cardiac catheterization to assess his left ventricular function prior to thoracic surgery What is his ejection fraction percentage, as determined

from the left ventricular pressure–volume curve illustrated below?

246 A 72-year-old man is hospitalized with a history of respiratory distress, fever, and fatigue An ECG reveals ST-segment and T-wave abnormalities and

echocardiography shows an ejection fraction of 30% Over the next several days, significant peripheral edema develops The edema is most likely caused by which ofthe following?

a Decreased capillary permeability

b Decreased arterial pressure

c Increased central venous pressure

d Increased lymphatic flow

e Increased plasma protein concentration

247 A 38-year-old man has a murmur that ceases with the onset of the second heart sound The second heart sound occurs at the onset of which phase of the cardiac

248 A 57-year-old man complains of palpitations that are relieved by pressing on his eyeball His ECG is shown below An increase in which of the following is most

likely to accompany this condition?

(Reproduced, with permission, from Crawford M H Current Diagnosis & Treatment: Cardiology, 3rd ed New York: M cGraw-Hill; 2009:260.)

a Left atrial pressure

b M AP

c Stroke volume

d Sympathetic tone

e Venous a wave

249 A 24-year-old woman undergoes an annual physical examination for participation on the varsity track team at her college While auscultating her heart sounds, the

sports medicine physician instructs the woman to take in a deep inspiration During this maneuver, he detects normal splitting of the second heart sound Which of thefollowing is the mechanism underlying this finding?

a A decrease in heart rate

b An increased left ventricular stroke volume

c Delayed closing of the aortic valve

d Delayed closing of the pulmonic valve

e Delayed opening of the mitral valve

250 A 68-year-old man presents for his quarterly cardiology examination Upon auscultation, a third heart sound is heard Of the following conditions, which is the

most likely cause of an S3?

251 A 23-year-old woman presents with fatigue She is found to have a mid-systolic murmur and higher-than-normal cardiac output The differential diagnosis based

on these findings includes which of the following?

a Anemia

b Cardiac tamponade

c M itral regurgitation

d M itral stenosis

e Third-degree heart block

252 A 22-year-old woman with lightheadedness and recurrent syncope is taken to the emergency department Her symptoms are relieved by intravenous atropine

administration Antagonism of cholinergic muscarinic receptors causes an increase in which of the following physiologic variables?

a Heart rate

b PR interval

c Stroke volume

d TPR

e Ventricular contractility

253 A 58-year-old woman presents for evaluation of headaches Her blood pressure is 170/70 mm Hg Her physical examination is otherwise unremarkable except for

a diastolic murmur heard best over the left sternal border During which phase of the pressure–volume loop below does the murmur occur?

a Segment A

b Segment B

c Segment C

d Segment D

254 Physical examination of a 41-year-old IV drug abuser reveals an early systolic murmur The physician also notes a 7-cm distance between the height of the blood

in his right internal jugular vein and sternal angle (normal = 3 cm) Which of the following conditions is most likely responsible for the physical findings?

255 A 50-year-old woman complains of intermittent chest discomfort She is given an exercise stress test to determine if the angina is a result of myocardial ischemia.

The test will be considered positive if which of the following occurs?

a An increase in mean arterial pressure

b Depression of the ST-segment

c Tachycardia

d A diastolic murmur

e Widening of the QRS complex

256 A 64-year-old woman is postoperative day 1 after a cholecystectomy She suddenly stands up after being supine since the operation As a result, which of the

following hemodynamic variables will increase?

a Heart rate

b M ean arterial pressure

c Stroke volume

d Venous return

e Ventricular end-diastolic volume

257 A newborn baby is cyanotic upon delivery The cyanosis is not relieved by breathing 100% oxygen A diagnosis of persistent fetal circulation is made based on

which of the following?

258 A 74-year-old black man with a past medical history significant for two previous myocardial infarctions presents with atrial fibrillation His ejection fraction by

echocardiography is 25% Which of the shifts in the cardiac function curves shown below are consistent with the changes in ventricular function that occur before and

after digitalis administration in a patient with congestive heart failure (CHF) assuming that normal function is depicted by the curve on which an X is marked?

259 A 19-year-old man severs an artery in a motorcycle accident A bystander applies a tourniquet to stop the bleeding When the paramedics arrive, the blood

pressure of the injured man was only slightly hypotensive and his pupils were reactive The greatest percentage of the redistributed blood volume came from which ofthe following?

a Aorta

b Arteries and arterioles

c Capillaries

d The heart

e Venules and veins

260 An 84-year-old woman presents with paroxysmal dizziness, syncope, confusion, and fatigue Her heart rate did not change when the patient was instructed to

perform a Valsalva maneuver A 24-hour Holter monitor revealed periodic episodes of sinus bradycardia Phase 4 of the pacemaker potential of SA nodal cells iscaused by which of the following?

a A decrease in the activity of the Na–K pump

b A decrease in the flow of potassium out of the cell

c An increase in the activity of the Na/Ca exchanger

d An increase in the flow of calcium into the cell

e An increase in the flow of sodium into the cell

261 During auscultation of a patient with long-standing hypertension, the physician notes that the splitting of the second heart sound is reversed with P2 occurringbefore A2 Which of the following is a common ECG finding accompanying paradoxical splitting of the second heart sound?

a Left bundle branch block

b Right bundle branch block

c Sinus arrhythmia

d Sinus bradycardia

e Sinus tachycardia

262 A 56-year-old man was admitted to the hospital with angina and diaphoresis A myocardial infarction is suspected, and a 12-lead ECG is ordered and shown

below The ECG is most effective in detecting a decrease in which of the following?

(Reproduced, with permission, from Fauci AS, Braunwald E, Kasper DL, et al Harrison’s Principles of Internal Medicine 17th ed New York: M cGraw-Hill;

2008:e19-e25.)

a Coronary blood flow

b Ejection fraction

c M ean blood pressure

d Total peripheral resistance

e Ventricular contractility

263 An 83-year-old woman with long-standing hypertension presents after a near-syncopal episode upon standing Her blood pressure is taken sitting and then

standing Systolic pressure decreased slightly and pulse pressure increased in the standing position Which of the following can lead to an increased pulse pressure?

a A decrease in stroke volume

b An increase in arterial compliance

c An increase in heart rate

d An increase in total peripheral resistance

e Stiffening of the arteries

264 A 75-year-old woman makes an appointment to see her physician because of exertional dyspnea and an episode of syncope while dancing with her husband at

their granddaughter’s wedding A systolic ejection murmur is auscultated that radiates to the carotid arteries Her signs and symptoms are most likely due to which ofthe following?

265 A 68-year-old sedentary, obese man with four-vessel coronary occlusive disease has a massive myocardial infarction while shoveling snow In the blizzard

conditions, it takes the ambulance over an hour to reach the man’s home When the paramedics arrive, the patient’s radial pulse is rapid and thready, he has pink frothcoming from his mouth, and he is nonresponsive Increasing which of the following would lead to an increased stroke volume in this patient?

a Heart rate

b Pulmonary capillary hydrostatic pressure

c Systemic vascular resistance

d Venous compliance

e Ventricular contractility

266 A pacemaker is inserted in a patient in order to treat a prolonged PR interval detected on the ECG Which of the following normally occurs during the PR

interval?

a The cardiac action potential passes through the AV node

b The mitral and aortic valves are both closed

c There is no change in the voltage tracing on the ECG

d The second heart sound is heard

e The ventricles are contracting

267 A 36-year-old athlete becomes alarmed when he notices a series of heart palpitations several hours after he exercises After examining the patient’s ECG, the

physician notes a sinus rhythm with occasional unifocal premature ventricular complexes (PVCs) Which of the following may predispose an athlete to the occurrence

268 A patient comes to his physician complaining that he is no longer able to exercise as long as he used to The physician auscultates crepitant rales and a third heart

sound; blood pressure is normal He sends the patient to cardiologist because of suspected heart failure Which of the following is most consistent with a diagnosis ofCHF?

a Decreased heart rate

b Decreased left ventricular energy consumption

c Decreased pulmonary arterial wedge pressure

d Increased left ventricular ejection fraction

e Increased left ventricular wall tension

269 Cardiac catheterization is performed on a 39-year-old man who presents with angina The left ventricular pressure–volume curve shows a decreased stroke

volume and ejection fraction Which of the following mechanisms may compromise stroke volume following myocardial infarction?

a Decreased arterial blood pressure

b Decreased total peripheral resistance

c Increased central venous pressure

d Increased heart rate

e Sympathetic-mediated positive inotropy

270 A 47-year-old man is brought to the emergency department because he had chest pain, was short of breath, and fainted at the gym during his daily workout A

prominent systolic ejection click and crescendodecrescendo systolic murmur is heard over the right sternal border Which of the following findings is consistent withthe patient’s most likely diagnosis?

a Decreased cardiac oxygen consumption

b Decreased left ventricular systolic pressure

c Decreased pulse pressure

d Increased arterial blood pressure

e Increased ejection fraction

271 A patient with an inferior M I develops a stable bradycardia of 50 beats per minute (bpm) The cardiologist orders an ECG to evaluate whether there is sinus node

dysfunction or an AV conduction disturbance The diagnosis of a first-degree heart block is made in which of the following cases?

a Asynchrony of P waves and QRS complexes

b Fixed, prolonged PR interval followed by a nonconducted QRS complex at regular intervals

c Normal PR interval, normal QRS complexes, increased R-R interval

d Prolonged PR interval with every P wave followed by a QRS complex

e The PR interval is progressively prolonged until a QRS complex is dropped

272 A 67-year-old man with a history of rheumatic heart disease presents with difficulty breathing when he exercises, which has worsened over the last year.

Auscultation reveals a holosystolic murmur at the left 5th intercostal space along the midclavicular line The murmur is loudest at the apex, radiates to the axilla, and isenhanced during expiration and when the patient is instructed to make a fist Which of the following findings is most likely to be present?

a Decreased arterial pressure

b Decreased left ventricular preload

c Increased cardiac output

d Increased pulse pressure

e Increased ν wave

273 Ventricular pressure–volume curves are determined in two different patients, as illustrated below Which of the following variables is greater in patient #1?

274 During a routine physical examination, a 35-year-old man is found to have a blood pressure of 170/105 mm Hg The history reveals episodes of headache

accompanied by palpitations, diaphoresis, and anxiety Which of the following is the best initial pharmacotherapy for this patient’s most likely diagnosis?

a α-Adrenergic agonist

b α-Adrenergic antagonist

c β-Adrenergic agonist

d β-Adrenergic antagonist

e Glycoprotein IIb/IIIa antagonist

275 A 43-year-old man comes to his physician complaining of exhaustion and shortness of breath After completing the physical examination, the physician suspects

the patient may be suffering from pericardial tamponade Which of the following observations led to the physician’s putative diagnosis?

a Bradycardia

b Expiratory rales

c Hypertension

d Pulsus paradoxus

e Third heart sound

276 Cardiac and vascular function curves were generated in a patient undergoing several maneuvers to evaluate his cardiac and cardiovascular reserves Starting from

the control point in the figure below, to which point did the curves shift when the person was given a transfusion of saline?

277 A 40-year-old woman with metabolic syndrome is prescribed a low-calorie diet and 30 minutes of daily aerobic exercise Sympathetic stimulation during exercise

has which of the following effects on the heart?

a A decrease in the cytosolic concentration of Ca2+ during systole

b A decrease in intracellular concentration of cyclic AM P

c An increase in the activity of the sarcoplasmic reticulum (SR) calcium pump

d An increase in the duration of diastole

e An increase in the duration of systole

278 A 37-year-old patient is brought to the emergency department in shock A decision is made to treat anaphylactic shock rather than hypovolemic shock based on

an increase in which of the following variables?

279 A 23-year-old collegiate dance squad member adopts a sedentary lifestyle once she starts medical school After the gross anatomy course, she decides to restore

her state of physical fitness by resuming a regular exercise routine The cardiovascular responses to isotonic exercise include an increase in which of the following?

281 A 2-year-old boy is mauled by a black bear while hiking with his family in the Appalachian M ountains A claw-puncture wound to the skull compressed the

underlying brain tissue Which of the following occurs in response to an increased intracranial pressure?

a Blood pressure and heart rate decrease

b Blood pressure and heart rate increase

c Blood pressure and heart rate remain constant

d Blood pressure decreases and heart rate increases

e Blood pressure increases and heart rate decreases

282 A 75-year-old woman presents to her primary care physician’s office in follow-up for her hypertension of 25 years She is currently on losartan Her ECG is

shown below

(Reproduced, with permission, from Fauci AS, Braunwald E, Kasper DL, et al Harrison’s Principles of Internal Medicine 17th ed New York: M cGraw-Hill;

2008:e19-e28.)

Considering the history and ECG findings, this patient’s left ventricular wall stress will be decreased by an increase in which of the following?

a Contractility of the left atrium

b Left ventricular end-diastolic volume

c M AP

d Thickness of the free wall of the left ventricle

e TPR

283 A 47-year-old man with type II diabetes reports for his 6-month checkup His doctor prescribes a daily 30-minute routine of walking at a brisk pace During

aerobic exercise, blood flow remains relatively constant to which of the following organs?

285 A 56-year-old man presents with complaints of fatigue and headaches During physical examination, he is found to have a wide pulse pressure Which of the

following conditions causes pulse pressure to increase?

286 A 48-year-old man develops chest pain while running His wife takes him to the emergency department, where the following ECG is obtained The ECG changes

are consistent with a diagnosis of which of the following?

a Anterior infarction

b Hyperkalemia

c Hypokalemia

d Posterior infarction

e Ventricular premature beat

287 A 63-year-old woman presents to the emergency room with complaints of dyspnea, an elevated jugular venous pulse, and bilateral lower extremity edema She is

prescribed captopril Which of the following best describes a beneficial effect of this drug?

288 A 29-year-old woman presents at the office of her obstetrician/gynecologist with breast tenderness She reports that her last menstrual period was 6 weeks ago.

An assay for human chorionic gonadotropin in her urine is positive During pregnancy, which of the following is true of the maternal and fetal circulations?

a Fetal CO2 that diffuses across the placenta is removed by the maternal uterine arteries

b The oxygen dissociation curve for fetal hemoglobin is shifted to the right of that of maternal hemoglobin A

c The highest partial pressure of oxygen in the fetus is in the umbilical arteries

d The majority of the fetal cardiac output goes to the placenta

e Uterine blood flow doubles

289 An EM T arrives at the scene of an automobile accident, and finds a hemorrhaging, unconscious young woman Which of the following is a sign of hemorrhagic

e Warm skin

290 The graph below illustrates the pressure–volume curves for the arterial and venous systems Which of the following is the approximate ratio of the arterial

compliance to the venous compliance?

291 A 6-day-old baby girl undergoes a routine physical examination She is found to be tachycardic, and has a wide pulse pressure A thrill and a continuous murmur

with late systolic accentuation at the upper left sternal edge are detected upon auscultation Which of the following best describes the in utero function of the mostlikely structure causing the murmur?

a It allows blood to flow from the aorta to the pulmonary artery

b It delivers oxygenated blood from the placenta to the left ventricle

c It diverts oxygenated blood away from the lungs to the aorta

d It is a high-resistance conduit, which helps to maintain normal fetal blood pressure

e It is located in the septum between the left and right atrium

292 A patient is referred to the heart station for exercise stress testing Baseline and exercise levels of cardiac and venous function are measured and plotted on the

graphs below The point marked “Control” represents baseline cardiovascular function in the resting state in the supine position During treadmill exercise, there will

be a shift from the resting state to which of the following points?

293 A 63-year-old woman presented with acute onset of right eye pain Ophthalmic and neurologic examinations were normal except for a loud right carotid bruit The

eye pain ceased following carotid endarterectomy The bruit was most likely caused by which of the following?

a High velocity of blood within the carotid artery

b Increase in blood viscosity

c Increase in hematocrit

d Lengthening of the carotid artery

e Widening of the carotid artery

294 In the pressure–volume loop below, systole begins at which of the following points?

295 A 57-year-old woman is undergoing a femoral popliteal bypass for her peripheral vascular disease The vascular surgeon wishes to induce a localized arteriolar

constriction to help control hemostasis An increase in the local concentration of which of the following agents will cause systemic vasoconstriction?

a Adenosine