Coronary Arteries and Veins Overview
57 Questions
8 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

Which artery quickly divides into the circumflex artery and the left anterior descending artery?

  • Left coronary artery (correct)
  • Great cardiac artery
  • Coronary sinus
  • Right coronary artery

    • What vessel accompanies the left anterior descending artery?

  • Circumflex artery
  • Great cardiac vein (correct)
  • Coronary sinus
  • Right coronary artery

    • During which phase of the cardiac cycle does almost all coronary blood flow occur?

  • Atrial contraction
  • Isovolumic relaxation
  • Systole
  • Diastole (correct)

    • What determines myocardial O2 supply based on the text?

    <p>Diastolic time, coronary O2 content, and coronary resistance</p> Signup and view all the answers

    What is the driving pressure for coronary perfusion gradient calculation in diastole?

    <p>Aortic root pressure</p> Signup and view all the answers

    Which vessel drains the coronary veins and runs in a groove between atria and ventricles?

    <p>Coronary sinus</p> Signup and view all the answers

    What determines coronary blood flow according to the text?

    <p>[Hb] &amp; type, 2,3-BPG levels</p> Signup and view all the answers

    True or False: Resistance vessel tone affects myocardial O2 demand.

    <p><strong>False</strong></p> Signup and view all the answers

    True or False: The majority of coronary blood flow occurs during systole.

    <p><strong>False</strong></p> Signup and view all the answers

    True or False: Coronary O2 supply depends solely on coronary resistance.

    <p><strong>False</strong></p> Signup and view all the answers

    What is the primary reason vessels get compressed during systole due to myocardial compression?

    <p>LV pressure &gt; Aortic root pressure</p> Signup and view all the answers

    What factor decreases resistance to allow more flow in coronary vessels?

    <p>High PO2</p> Signup and view all the answers

    Which factor plays a crucial role in determining resting resistance vessel tone?

    <p>Heart metabolic state</p> Signup and view all the answers

    What protects against wall stress in the myocardium?

    <p>Myocardial hypertrophy</p> Signup and view all the answers

    What is the relationship between ventricular end diastolic volume and ventricular performance known as?

    <p>Frank-Starling relationship</p> Signup and view all the answers

    Complete the statement: Myocardium depends entirely on ____________ for meeting its oxygen demand.

    <p>Aerobic metabolism</p> Signup and view all the answers

    Inadequate perfusion leading to angina is a result of:

    <p>Coronary artery plaque reducing blood flow</p> Signup and view all the answers

    What level of stenosis in coronary vessels typically leads to stable angina during exercise?

    <p>~75%</p> Signup and view all the answers

    What is the primary manifestation of a complete occlusion of coronary vessels?

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

    What does myocardial hypertrophy do to protect the heart from wall stress?

    <p>Increases wall thickness</p> Signup and view all the answers

    During which phase of the cardiac cycle does almost all coronary blood flow occur?

    <p>Early diastole</p> Signup and view all the answers

    What factor primarily determines myocardial O2 supply based on the text?

    <p>Coronary O2 content</p> Signup and view all the answers

    What is the primary manifestation of a complete occlusion of coronary vessels?

    <p>Myocardial infarction</p> Signup and view all the answers

    Which vessel is responsible for draining the coronary veins according to the text?

    <p>Coronary sinus</p> Signup and view all the answers

    What is the driving pressure for coronary perfusion gradient calculation in diastole?

    <p>$90 - 10$</p> Signup and view all the answers

    What factor protects against wall stress in the myocardium?

    <p>$2,3-BPG$ availability</p> Signup and view all the answers

    True or False: The majority of coronary blood flow takes place during systole.

    <p><strong>False</strong></p> Signup and view all the answers

    What is the primary mechanism responsible for the compression of vessels during systole due to myocardial compression?

    <p>Equivalence of aortic root pressure and LV pressure</p> Signup and view all the answers

    Which of the following factors is NOT a determinant of resting resistance vessel tone according to the text?

    <p>Myocardial blood oxygen level</p> Signup and view all the answers

    What effect does myocardial hypertrophy have on protecting the heart from wall stress?

    <p>Reduces wall stress</p> Signup and view all the answers

    How is myocardial O2 demand primarily met according to the information provided?

    <p>Through aerobic metabolism</p> Signup and view all the answers

    Which factor is NOT involved in determining myocardial O2 demand according to the text?

    <p>Ventricular performance</p> Signup and view all the answers

    What factor plays a significant role in decreasing resistance to allow more flow in coronary vessels?

    <p>Increased K+ levels</p> Signup and view all the answers

    Which of the following is a neurogenic factor that contributes to resting resistance vessel tone?

    <p>Receptors that vasoconstrict</p> Signup and view all the answers

    What happens when there is inadequate perfusion leading to angina?

    <p>Myocardial ischemia</p> Signup and view all the answers

    What determines coronary blood flow primarily according to the text?

    <p>Metabolic state of the heart</p> Signup and view all the answers

    What causes stable angina according to the text?

    <p>Inadequate perfusion during rest</p> Signup and view all the answers

    What determines coronary resistance according to the text?

    <p>Tone &amp; stenoses of conductance vessels</p> Signup and view all the answers

    During which phase of the cardiac cycle does almost all coronary blood flow occur?

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

    What primarily determines myocardial O2 supply based on the text?

    <p>Coronary perfusion gradient</p> Signup and view all the answers

    How does myocardial hypertrophy contribute to protecting the heart from wall stress?

    <p>By enhancing myocardial compression</p> Signup and view all the answers

    Which factor plays a significant role in decreasing resistance to allow more flow in coronary vessels?

    <p>Coronary O2 content availability</p> Signup and view all the answers

    What is the driving pressure for coronary perfusion gradient calculation in diastole?

    <p>$120 - 90$</p> Signup and view all the answers

    What protects against wall stress in the myocardium?

    <p>$2,3$-BPG availability</p> Signup and view all the answers

    True or False: The majority of coronary blood flow takes place during systole.

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

    True or False: Resistance vessel tone affects myocardial O2 demand.

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

    What happens when there is inadequate perfusion leading to angina?

    <p>Myocardial infarction</p> Signup and view all the answers

    What determines the resting resistance vessel tone primarily?

    <p>Myocardial metabolism</p> Signup and view all the answers

    Which factor significantly contributes to decreasing resistance in coronary vessels to allow more flow?

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

    What factor has the most significant impact on decreasing resistance to allow more flow in coronary vessels?

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

    Which factor is NOT involved in determining the myocardial O2 demand?

    <p>Oxygen tension</p> Signup and view all the answers

    How is myocardial O2 demand principally met?

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

    What is the role of endothelin in coronary vessels?

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

    Which factor primarily determines myocardial O2 supply based on the text?

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

    What is the main role of nitric oxide in coronary vessels?

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

    What is the primary way myocardial O2 demand is met according to the text?

    <p>Myocardium metabolism</p> Signup and view all the answers

    What plays the most important role in determining the resting resistance vessel tone according to the information provided?

    <p>Metabolic factors</p> Signup and view all the answers

    Study Notes

    Coronary Circulation Overview

    • The left coronary artery divides swiftly into the circumflex artery and the left anterior descending artery.
    • The left anterior descending artery is accompanied by the great cardiac vein.
    • Almost all coronary blood flow occurs during diastole.

    Myocardial Oxygen Supply and Demand

    • Myocardial oxygen supply is primarily determined by coronary blood flow, which is influenced by the coronary resistance.
    • The driving pressure for calculating the coronary perfusion gradient in diastole is the difference between diastolic blood pressure and ventricular pressure.
    • Resistance vessel tone plays a crucial role in affecting myocardial oxygen demand.

    Impact of Cardiac Cycle on Coronary Blood Flow

    • The majority of coronary blood flow actually occurs during diastole, not systole.
    • The compression of coronary vessels during systole is mainly caused by myocardial contraction.
    • A change in vascular resistance allows increased blood flow in coronary vessels during diastole.

    Clinical Implications

    • Stable angina typically arises when there's about 70% stenosis in coronary vessels, especially during exertion.
    • A complete occlusion of coronary vessels leads to myocardial infarction.
    • Inadequate perfusion leading to angina occurs when the oxygen demand exceeds the supply.

    Physiological Adaptations

    • Myocardial hypertrophy helps mitigate wall stress by redistributing myocardial mass.
    • The relationship between ventricular end-diastolic volume and ventricular performance is known as the Frank-Starling mechanism.
    • Factors contributing to resting resistance vessel tone include metabolic and neurogenic influences, such as endothelin and nitric oxide, which help regulate vascular tone.

    Misconceptions

    • False: The majority of coronary blood flow occurs during systole (it occurs during diastole).
    • False: Coronary oxygen supply depends solely on coronary resistance (it also depends on blood flow and other factors).

    Role of Key Factors

    • Endothelin serves as a vasoconstrictor in coronary vessels.
    • Nitric oxide acts as a vasodilator, significantly contributing to coronary blood flow.
    • Myocardial oxygen demand is affected by factors such as heart rate, contractility, and wall tension.

    Summary of Conditions

    • Stenosis and reduced blood flow can lead to myocardial ischemia and symptoms like angina.
    • Management of these conditions often involves interventions to improve coronary blood flow and reduce myocardial oxygen demand.

    Studying That Suits You

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

    Quiz Team

    Description

    This quiz covers the key coronary arteries such as the right and left coronary arteries which arise from the root of the aorta, as well as the coronary veins including the great cardiac vein and coronary sinus. Explore the structures responsible for supplying and draining blood in the heart.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser