Cardiac Physiology Quiz
84 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is stroke volume (SV)?

  • The total volume of red blood cells in circulation
  • The total amount of blood pumped by the heart in one minute
  • The pressure exerted by circulating blood on the walls of blood vessels
  • The amount of blood pumped out by the heart in one beat (correct)

    • Which equation correctly represents cardiac output (CO)?

  • CO = SV × HR (correct)
  • CO = SV + HR
  • CO = SV - HR
  • CO = SV / HR

    • What effect does digoxin have on stroke volume?

  • It increases stroke volume by enhancing calcium availability (correct)
  • It decreases stroke volume by reducing heart contractility
  • It increases stroke volume by accelerating heart rate
  • It has no effect on stroke volume

    • How does increased viscosity of blood typically affect blood flow resistance?

    <p>It causes a substantial increase in blood flow resistance</p> Signup and view all the answers

    What impact does stroke volume have on blood pressure?

    <p>Higher stroke volumes generally increase blood pressure</p> Signup and view all the answers

    What percentage of blood is normally ejected from the ventricle during systole?

    <p>55-60%</p> Signup and view all the answers

    Which condition would most likely result in a low ejection fraction?

    <p>Heart failure</p> Signup and view all the answers

    What happens to the pressure gradient required to maintain blood flow if the resistance doubles?

    <p>It doubles</p> Signup and view all the answers

    How does increased body weight affect blood flow resistance?

    <p>Increases resistance</p> Signup and view all the answers

    What is the role of viscosity in blood flow?

    <p>It decreases blood flow</p> Signup and view all the answers

    What defines turbulent flow in blood vessels?

    <p>Disruption due to high velocities or narrowed vessels</p> Signup and view all the answers

    When does the S4 heart sound typically occur?

    <p>During late diastole</p> Signup and view all the answers

    What physiological condition is associated with an S3 heart sound in adults?

    <p>Dilated left ventricles</p> Signup and view all the answers

    What effect does sympathetic activation primarily have on systemic vascular resistance (SVR)?

    <p>It increases SVR through vasoconstriction.</p> Signup and view all the answers

    Which of the following substances is NOT involved in the contraction of vascular smooth muscle?

    <p>Nitric Oxide</p> Signup and view all the answers

    Which factor contributes to an increase in cardiac output under sympathetic activation?

    <p>Increased heart rate (HR)</p> Signup and view all the answers

    What equation represents perfusion pressure?

    <p>Perfusion Pressure = MAP - CVP</p> Signup and view all the answers

    Which neurohumoral factor primarily promotes sodium retention and consequently increases blood volume?

    <p>Renin-angiotensin-aldosterone system</p> Signup and view all the answers

    What effect does vasovagal syncope have on blood flow to the brain?

    <p>It decreases blood flow due to bradycardia and low blood pressure.</p> Signup and view all the answers

    Which of the following local factors is associated with vasodilation?

    <p>Nitric Oxide</p> Signup and view all the answers

    How does an increase in stroke volume affect blood pressure?

    <p>It increases blood pressure.</p> Signup and view all the answers

    What primarily affects the stroke volume (SV) during periods of increased heart rate?

    <p>Increased venous return</p> Signup and view all the answers

    Which factor is likely to lead to a decrease in blood pressure?

    <p>Decreased peripheral resistance</p> Signup and view all the answers

    How does increased blood viscosity typically impact blood flow resistance?

    <p>Increases resistance and decreases flow</p> Signup and view all the answers

    Which of the following would NOT typically increase stroke volume?

    <p>Lower heart rate</p> Signup and view all the answers

    What is the primary consequence of utilizing digoxin in heart conditions concerning stroke volume?

    <p>It enhances myocardial contractility.</p> Signup and view all the answers

    What percentage of blood ejected from the ventricle during systole is considered normal?

    <p>55-60%</p> Signup and view all the answers

    What happens to the required pressure gradient if blood flow resistance is doubled?

    <p>It doubles.</p> Signup and view all the answers

    How does increased body weight influence blood flow resistance?

    <p>It increases resistance.</p> Signup and view all the answers

    Which factor is NOT typically associated with turbulent flow in blood vessels?

    <p>Regular vessel structure.</p> Signup and view all the answers

    Which heart sound is associated with late diastole during atrial contraction?

    <p>S4 Sound</p> Signup and view all the answers

    What does a low ejection fraction typically indicate?

    <p>Heart failure.</p> Signup and view all the answers

    What kind of flow occurs when laminar flow is disrupted by high velocities?

    <p>Turbulent flow.</p> Signup and view all the answers

    What is the relationship between viscosity and blood flow resistance?

    <p>Higher viscosity increases resistance.</p> Signup and view all the answers

    What is the primary effect of sympathetic activation on systemic vascular resistance (SVR)?

    <p>It increases vascular resistance.</p> Signup and view all the answers

    Which local factor is primarily associated with vasodilation in blood vessels?

    <p>Nitric Oxide</p> Signup and view all the answers

    How does increased blood volume through renal receptor activation affect cardiac preload?

    <p>It increases cardiac preload.</p> Signup and view all the answers

    What is the main action of the renin-angiotensin-aldosterone system when activated?

    <p>Enhance sodium retention and blood volume.</p> Signup and view all the answers

    What effect does bradykinin have on blood vessels?

    <p>Promotes vasodilation.</p> Signup and view all the answers

    In the context of blood pressure regulation, which effect do vasovagal syncope episodes have?

    <p>Decrease in heart rate and blood pressure.</p> Signup and view all the answers

    Which neurotransmitter is primarily associated with increasing cardiac output during sympathetic activation?

    <p>Norepinephrine</p> Signup and view all the answers

    Which factor is likely to lead to increased blood flow resistance?

    <p>Increased viscosity of the blood</p> Signup and view all the answers

    During which phase of the cardiac cycle does the left ventricular pressure increase without a change in volume?

    <p>Isovolumetric Contraction</p> Signup and view all the answers

    What is the primary factor that affects the left ventricular end diastolic volume (LVEDV)?

    <p>Volume of blood received from the atrium</p> Signup and view all the answers

    What occurs during the rapid ejection phase of the cardiac cycle?

    <p>Blood is forcefully ejected into the aorta</p> Signup and view all the answers

    Which statement best describes the relationship between blood viscosity and resistance to blood flow?

    <p>Higher viscosity typically increases resistance</p> Signup and view all the answers

    What is the consequence of increased resistance on blood flow during the cardiac cycle?

    <p>Potential for decreased blood flow</p> Signup and view all the answers

    What does a high ejection fraction typically indicate regarding ventricular function?

    <p>Normal heart function and adequate systolic performance</p> Signup and view all the answers

    Which of the following statements about blood viscosity is correct?

    <p>Lower viscosity results in an increase in cardiac output</p> Signup and view all the answers

    Which scenario would most likely lead to an increase in blood flow resistance?

    <p>Increased plaque buildup in arterial walls</p> Signup and view all the answers

    What condition is associated with a significant reduction in ejection fraction?

    <p>Dilated left ventricle due to cardiomyopathy</p> Signup and view all the answers

    In terms of maintaining the same flow, what happens when the resistance in the system doubles?

    <p>The pressure gradient must double to maintain flow</p> Signup and view all the answers

    Which of the following correctly describes how increased body weight affects blood flow resistance?

    <p>Increased body weight increases resistance due to higher systemic demands</p> Signup and view all the answers

    What characterizes turbulent flow in blood vessels?

    <p>It usually happens in situation of narrowed vessels and high velocities</p> Signup and view all the answers

    During which cardiac event does atrial contraction primarily contribute to ventricular filling?

    <p>Late diastole just before systole</p> Signup and view all the answers

    What primarily influences the dilation of blood vessels?

    <p>Nitric Oxide</p> Signup and view all the answers

    Which factor contributes most to an increase in systemic vascular resistance (SVR)?

    <p>Vasoconstriction due to sympathetic activation</p> Signup and view all the answers

    Which hormone primarily promotes sodium retention to increase blood volume?

    <p>Aldosterone</p> Signup and view all the answers

    In which condition would an increase in blood flow resistance most likely occur?

    <p>Increased blood viscosity</p> Signup and view all the answers

    Which scenario would lead to a decrease in cardiac output?

    <p>Reduced heart rate through vagal influence</p> Signup and view all the answers

    Which of the following factors is associated with contraction of vascular smooth muscle?

    <p>Calcium ions</p> Signup and view all the answers

    What is the key consequence of an increase in systemic vascular resistance?

    <p>Increased perfusion pressure</p> Signup and view all the answers

    Which factor is unlikely to directly affect blood pressure?

    <p>Ventilation rates</p> Signup and view all the answers

    How does increased blood volume influence stroke volume?

    <p>It enhances stroke volume through increased preload.</p> Signup and view all the answers

    What effect does increased stroke volume have on blood pressure, assuming heart rate remains constant?

    <p>It increases blood pressure.</p> Signup and view all the answers

    Under what condition would blood viscosity most likely increase, affecting blood flow resistance?

    <p>Dehydration.</p> Signup and view all the answers

    What relationship exists between stroke volume and cardiac output when heart rate is reduced?

    <p>Cardiac output decreases if stroke volume decreases.</p> Signup and view all the answers

    Which factor is least likely to directly reduce blood flow resistance in vessels?

    <p>Elevated viscosity.</p> Signup and view all the answers

    Which factor can decrease stroke volume under physical stress conditions?

    <p>Increased afterload.</p> Signup and view all the answers

    Which physiological effect is primarily caused by an increase in blood viscosity?

    <p>Elevated blood pressure.</p> Signup and view all the answers

    When blood flow resistance increases due to increased viscosity, what compensatory mechanism is most affected?

    <p>Heart rate increases to maintain output.</p> Signup and view all the answers

    In the context of heart failure, which aspect related to stroke volume is most critical to monitor?

    <p>Ejection fraction.</p> Signup and view all the answers

    How does a decrease in stroke volume influence the resistance encountered in the vascular system?

    <p>It can increase vascular resistance by promoting vasoconstriction.</p> Signup and view all the answers

    What impact does digoxin have on stroke volume when considering its mechanism of action?

    <p>It increases stroke volume by enhancing calcium availability for contraction.</p> Signup and view all the answers

    What does a decrease in the end-diastolic volume (EDV) typically indicate about stroke volume (SV)?

    <p>It likely decreases SV.</p> Signup and view all the answers

    How is stroke volume (SV) primarily affected during increased blood viscosity?

    <p>It decreases due to increased resistance.</p> Signup and view all the answers

    In what situation would you expect an increase in blood pressure regarding stroke volume?

    <p>When stroke volume increases at a constant heart rate.</p> Signup and view all the answers

    What effect does high blood flow resistance generally have on blood pressure?

    <p>It raises blood pressure.</p> Signup and view all the answers

    Which of the following conditions is likely to decrease stroke volume?

    <p>Increased end-systolic volume.</p> Signup and view all the answers

    Which factor does NOT typically contribute to increased blood viscosity?

    <p>Low levels of plasma proteins.</p> Signup and view all the answers

    How would an increase in stroke volume directly affect the workload of the heart?

    <p>It causes the heart to work harder.</p> Signup and view all the answers

    What primarily regulates the stroke volume in response to increased venous return?

    <p>Increased end-diastolic volume.</p> Signup and view all the answers

    What happens to systemic blood pressure if stroke volume is consistently below normal levels?

    <p>Blood pressure drops unless other factors compensate.</p> Signup and view all the answers

    What is the likely effect on cardiovascular function with a sudden increase in blood viscosity?

    <p>Increased resistance leading to reduced blood flow.</p> Signup and view all the answers

    Study Notes

    Cardiac Conduction System

    • Pacemaker cells initiate heartbeat; "funny" sodium channels (HCN) cause slow depolarization.
    • L-type calcium channels trigger depolarization.
    • Action potential phases in cardiac contractile cells (myocardial cells) are detailed.
    • ECG correlations exist with specific intervals (PR, QT).
    • Depolarization propagates through ventricular myocytes via gap junctions.
    • Temperature affects cardiac electrophysiology.
    • Gas stimulates adenylyl cyclase.

    Cardiac Cycle

    • Systole (ventricular contraction) and diastole (ventricular relaxation) are key phases.
    • Events like ejection and filling of the heart occur during these phases.
    • Normal ranges for end-diastolic volume (EDV) and end-systolic volume (ESV) exist.
    • The cardiac cycle involves early diastolic filling phase.
    • Atrial systole precedes ventricular systole.

    Cardiac Output (CO) and Stroke Volume (SV)

    • Cardiac output (CO) is the volume of blood pumped per minute.
    • Stroke volume (SV) is the volume of blood pumped per beat.
    • Relationship between CO and SV is crucial.
    • Stroke volume is dependent upon EDV and ESV.
    • SV is calculated by subtracting end-systolic volume (ESV) from end-diastolic volume (EDV).

    Key Pressures and Volumes Summary

    • End-diastolic volume (EDV), end-systolic volume (ESV), and other volumes are summarised with corresponding pressures.
    • Central Venous Pressure (CVP) is negligible (0 mmHg).

    Blood Pressure Determinants

    • Arterial pressure is the driving force for blood flow.
    • Main determinants of arterial pressure include: sympathetic activity, heart rate (HR), stroke volume (SV), and vascular resistance (SVR).
    • Local factors affecting blood pressure include PGE, PGI2, PGE2, and NO (nitric oxide).

    Effects of Sympathetic Activation

    • Sympathetic activation increases heart rate (HR) and stroke volume (SV).
    • 8-Adrenergic receptors are involved.

    ECG Correlation and Phases

    • QRS complex is described in detail during depolarization phases.
    • Q wave - initial downward deflection.
    • Sharp upward deflection (R wave)
    • Return to baseline (ST segment)
    • Final ventricular depolarization.

    Additional Notes

    • Mean vector and instantaneous vectors relating to electricity (electrical dipoles) are described.
    • Turbulent vs laminar blood flow is mentioned briefly.
    • Atrial systole occurs before ventricular systole.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Cardiovascular System PDF

    Description

    Test your knowledge on the cardiac conduction system, the phases of the cardiac cycle, and key measurements like cardiac output and stroke volume. This quiz covers essential concepts related to heart function and the events that occur during contraction and relaxation.

    More Like This

    Cardiac Physiology and Heart Failure Quiz
    28 questions

    Cardiac Physiology and Heart Failure Quiz

    WellPinkTourmaline avatar
    WellPinkTourmaline
    Heart Structure and Function Quiz
    16 questions

    Heart Structure and Function Quiz

    BrightestObsidian118 avatar
    BrightestObsidian118
    Cardiac Physiology and Function Quiz
    42 questions

    Cardiac Physiology and Function Quiz

    ValuableHeliotrope5203 avatar
    ValuableHeliotrope5203
    Circulatory System - Heart Functions
    10 questions

    Circulatory System - Heart Functions

    CalmFairy avatar
    CalmFairy
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser