00
Correct
00
Incorrect
00 : 00 : 00
Session Time
00 : 00
Average Question Time ( Secs)
Retry this test Dashboard

  • Question 1 - Which of the following occurs during a Valsalva manoeuvre? ...

    Incorrect

    • Which of the following occurs during a Valsalva manoeuvre?

      Your Answer: Disruption of autonomic function

      Correct Answer: An initial rise in blood pressure

      Explanation:

      The Valsalva maneuver involves forced expiration against a closed glottis. It has several phases, each affecting the cardiovascular system differently:

      1. Phase I: During the initial forced expiration against the closed glottis, there is a transient rise in intrathoracic pressure, which compresses the thoracic aorta and causes a brief increase in blood pressure.
      2. Phase II: Continued straining leads to decreased venous return to the heart, reducing cardiac output and causing a drop in blood pressure. This phase is characterized by a compensatory increase in heart rate.
      3. Phase III: Upon releasing the strain, there is a sudden drop in intrathoracic pressure, which momentarily decreases blood pressure.
      4. Phase IV: Blood pressure then rises rapidly as venous return to the heart is restored, leading to increased cardiac output. This is often followed by a reflex bradycardia (slow heart rate).

      Given these phases, the most accurate statement about what occurs during the Valsalva maneuver is the initial rise in blood pressure (Phase I).

      Other options explained:

      • Forced inspiration against a closed glottis: Incorrect. The Valsalva maneuver involves forced expiration, not inspiration, against a closed glottis.
      • Low intrathoracic pressures throughout: Incorrect. The Valsalva maneuver involves high intrathoracic pressures due to forced expiration.
      • Disruption of autonomic function: Incorrect. The Valsalva maneuver affects autonomic function but does not disrupt it. Instead, it triggers autonomic responses to changes in blood pressure and heart rate.
      • No change: Incorrect. The Valsalva maneuver causes significant changes in blood pressure and heart rate.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      147.3
      Seconds

  • Question 2 - Arterioles stemming from the coronary artery can also empty into the heart directly...

    Incorrect

    • Arterioles stemming from the coronary artery can also empty into the heart directly via the:

      Your Answer: Coronary cardiac shunt vessels

      Correct Answer: Arteriosinusoidal vessels

      Explanation:

      Most of the venous blood returns to the heart via the coronary sinus and the anterior cardiac veins. Apart from these there are other vessels that drain directly into the heart chambers. They include arteriosinusoidal vessels, which connect the arterioles to the heart chambers. The thebesian veins drain the capillaries into the chambers and the arterioluminal vessels drain small arteries directly into the chambers.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      212.6
      Seconds

  • Question 3 - Ventricular depolarization plus ventricular repolarization is shown by the _____ interval ...

    Incorrect

    • Ventricular depolarization plus ventricular repolarization is shown by the _____ interval

      Your Answer: QRS

      Correct Answer: QT

      Explanation:

      The QT interval represents ventricular depolarization as well as ventricular repolarization.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      72.1
      Seconds

  • Question 4 - Initial depolarization of cardiac muscle is due to influx of: ...

    Correct

    • Initial depolarization of cardiac muscle is due to influx of:

      Your Answer: Na+

      Explanation:

      Initial depolarization of the cardiac muscle results from opening of the sodium voltage gated channels. This results in the influx of sodium and an increase in the membrane potential towards threshold. Potassium efflux results in repolarization.

      The cardiac action potential has 5 phases:

      • Phase 0—depolarization because of the opening of fast sodium channels. Potassium flux also decreases.
      • Phase 1—partial repolarization because of a rapid decrease in sodium ion passage as fast sodium channels close.
      • Phase 2—plateau phase in which the movement of calcium ions out of the cell, maintains depolarization.
      • Phase 3—repolarization, sodium, and calcium channels all close and membrane potential returns to baseline.
      • Phase 4—resting membrane potential (−90 mV), resulting from the activity of the Na+/K+ ATPase pump which creates a negative intracellular potential because of the exchange of three sodium ions for only two potassium ions.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      23.4
      Seconds

  • Question 5 - When looking at the JVP what does the c wave signify: ...

    Incorrect

    • When looking at the JVP what does the c wave signify:

      Your Answer: Atrial systole

      Correct Answer: Isovolumetric ventricular contraction

      Explanation:

      The C wave signifies a rise in the atrial pressure during isovolumetric contraction due to the tricuspid valve bulging into the atria.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      195.2
      Seconds

  • Question 6 - Absolute refractory period in a cardiac action potential graph occurs during. ...

    Incorrect

    • Absolute refractory period in a cardiac action potential graph occurs during.

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      Absolute refractory period (ARP): the cell is completely unexcitable to a new stimulus and occurs from phase 0 – 2 i.e. depolarisation, early repolarisation and plateau phase.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 7 - Dicrotic notch is produced by which valves? ...

    Incorrect

    • Dicrotic notch is produced by which valves?

      Your Answer:

      Correct Answer: Aortic

      Explanation:

      The graph of aortic pressure throughout the cardiac cycle displays a small dip (the incisure or dicrotic notch) which coincides with the aortic valve closure. The dip in the graph is immediately followed by a brief rise (the dicrotic wave) then gradual decline.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 8 - During which phase of the cardiac cycle does most of the ventricular filling...

    Incorrect

    • During which phase of the cardiac cycle does most of the ventricular filling occur?

      Your Answer:

      Correct Answer: Ventricular diastole

      Explanation:

      During the phase of ventricular diastole when the heart muscle relaxes and all the valves are open, blood flows easily into the heart. This is the phase of rapid ventricular filling. During isovolumetric contraction and relaxation the volume of blood in the heart does not change. During ventricular ejection blood enters into the aorta and pulmonary vessels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 9 - B1 adrenergic stimulation produces: ...

    Incorrect

    • B1 adrenergic stimulation produces:

      Your Answer:

      Correct Answer: Increase in calcium cytosolic concentration

      Explanation:

      Norepinephrine secreted by the sympathetic endings binds to B1 receptors, and the resulting increase in intracellular cAMP facilitates the opening of L channels, increasing Ica and the rapidity of the depolarization phase of the impulse and activates PKA which leads to phosphorylation of the voltage-gated Ca2+ channels, causing them to spend more time in the open state.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 10 - Cholinergic nerves from the vagus innervate the SA and AV nodes via which...

    Incorrect

    • Cholinergic nerves from the vagus innervate the SA and AV nodes via which receptor in the heart?

      Your Answer:

      Correct Answer: M2 receptor

      Explanation:

      M2 receptor is found in the heart. M3 and M4 are associated with smooth muscle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 11 - Which of the following components regulate cardiac output? ...

    Incorrect

    • Which of the following components regulate cardiac output?

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      Cardiac output is regulated by the autonomic nervous system with sympathetic nerves having a positive chronotropic and inotropic effect and parasympathetic nerves having the opposite effect. An increase in preload will increase cardiac output likewise an afterload increase will also increase cardiac output.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 12 - The function of Troponin T in cardiac muscle is? ...

    Incorrect

    • The function of Troponin T in cardiac muscle is?

      Your Answer:

      Correct Answer: Allows attachment of troponin components to tropomyosin

      Explanation:

      Troponin T binds the troponin components to tropomyosin. Troponin I inhibits the interaction of myosin with actin, and troponin C contains the binding sites for the Ca2+ that helps initiate contraction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 13 - Which membrane bound protein in the sarcoplasmic reticulum regulates calcium return from the...

    Incorrect

    • Which membrane bound protein in the sarcoplasmic reticulum regulates calcium return from the cytosol to the sarcoplasmic reticulum?

      Your Answer:

      Correct Answer: Phospholamban

      Explanation:

      Phosphorylation of phospholamban increases calcium ATPase activity and sequestration of calcium in the sarcoplasmic reticulum. An increased rate of relaxation is explained because cAMP also activates the protein phospholamban, situated on the membrane of the sarcoplasmic reticulum (SR), that controls the rate of uptake of calcium into the SR. The latter effect explains enhanced relaxation (lusitropic effect).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 14 - Impulse conduction through the AV node is slow and depends on the action...

    Incorrect

    • Impulse conduction through the AV node is slow and depends on the action potential produced by which of the following.

      Your Answer:

      Correct Answer: Calcium flux

      Explanation:

      The action potentials in the SA and AV nodes are largely due to Ca2+, with no contribution by Na+ influx.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 15 - A sarcomere is the area between: ...

    Incorrect

    • A sarcomere is the area between:

      Your Answer:

      Correct Answer: Two adjacent z lines

      Explanation:

      The area that lies between the two adjacent Z lines is known as a sarcomere and is the contractile unit of the muscle. The line passing in the middle of the myosin filaments is the M line. It also passes through the middle of the sarcomere.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 16 - AV valves open during? ...

    Incorrect

    • AV valves open during?

      Your Answer:

      Correct Answer: Early diastole

      Explanation:

      The cardiac cycle refers to a complete heartbeat from its generation to the beginning of the next beat, and so includes the diastole, the systole, and the intervening pause.The first stage, diastole, is when the semilunar valves (the pulmonary valve and the aortic valve) close, the atrioventricular (AV) valves (the mitral valve and the tricuspid valve) open, and the whole heart is relaxed. The second stage, atrial systole, is when the atrium contracts, and blood flows from atrium to the ventricle.The third stage, isovolumic contraction is when the ventricles begin to contract, the AV and semilunar valves close, and there is no change in volume. The fourth stage, ventricular ejection, is when the ventricles are contracting and emptying, and the semilunar valves are open. During the fifth stage, isovolumic relaxation time, pressure decreases, no blood enters the ventricles, the ventricles stop contracting and begin to relax, and the semilunar valves close due to the pressure of blood in the aorta.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 17 - Concerning surface anatomy, where is the mitral valve found? ...

    Incorrect

    • Concerning surface anatomy, where is the mitral valve found?

      Your Answer:

      Correct Answer: Situated in the 4th intercostal space to the left of the sternum

      Explanation:

      The mitral valve is situated in the left 4th intercostal space just beneath the sternum.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 18 - The ability of the SA node cells to allow ionic flow through channels...

    Incorrect

    • The ability of the SA node cells to allow ionic flow through channels activated in a hyperpolarized state is known as:

      Your Answer:

      Correct Answer: Pace maker potential

      Explanation:

      Rhythmically discharging cells have a membrane potential that, after each impulse, declines to the firing level. Thus this prepotential or Pacemaker potential triggers the next impulse. The inherent leakiness of the sinus nodal fibers to Na+ and Ca2+ causes their self excitation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 19 - The following products of the vascular endothelium produce vasodilation except: ...

    Incorrect

    • The following products of the vascular endothelium produce vasodilation except:

      Your Answer:

      Correct Answer: Endothelin

      Explanation:

      Endothelin: This is incorrect in the context of vasodilation. Endothelin is actually a potent vasoconstrictor produced by the endothelium, leading to the narrowing of blood vessels and increased blood pressure.

      Nitrous oxide (Nitric oxide): This is correct for vasodilation. Nitric oxide is a powerful vasodilator produced by the endothelium, which helps relax and widen blood vessels.

      Prostacyclin: This is correct for vasodilation. Prostacyclin (PGI2) is a vasodilator and inhibits platelet aggregation, helping to maintain blood flow and reduce clot formation.

      Endothelial-derived hyperpolarizing factor (EDHF): This is correct for vasodilation. EDHF causes vasodilation by hyperpolarizing the smooth muscle cells of blood vessels.

      Vascular endothelial growth factor (VEGF): This is correct for vasodilation. VEGF primarily promotes the growth of new blood vessels but also has vasodilatory effects through nitric oxide production.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 20 - Regarding blood supply to the heart; ...

    Incorrect

    • Regarding blood supply to the heart;

      Your Answer:

      Correct Answer: Coronary arteries fill as the heart relaxes

      Explanation:

      The heart muscles acts like the skeletal muscle in the fact that it also compress the vessels during contraction. As the pressure in the ventricle is slightly greater than in the aorta the coronary vessels collapse during systole. Blood flows through them during the diastole phase of contraction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 21 - The steps of cardiac cycle in sequence are: ...

    Incorrect

    • The steps of cardiac cycle in sequence are:

      Your Answer:

      Correct Answer: Isovolumic contraction, ejection, isovolumic relaxation, passive ventricular filling, active ventricular filling.

      Explanation:

      The cardiac cycle refers to a complete heartbeat from its generation to the beginning of the next beat, and so includes the diastole, the systole, and the intervening pause.1st stage: diastole, or passive filling is when the semilunar valves (the pulmonary valve and the aortic valve) close, the atrioventricular (AV) valves (the mitral valve and the tricuspid valve) open, and the whole heart is relaxed. 2nd stage: atrial systole, is when the atrium contracts, and blood flows from atrium to the ventricle (active filling).3rd stage: isovolumic contraction is when the ventricles begin to contract, the AV and semilunar valves close, and there is no change in volume. 4th stage: ventricular ejection, is when the ventricles are contracting and emptying, and the semilunar valves are open. 5th stage: isovolumic relaxation time, pressure decreases, no blood enters the ventricles, the ventricles stop contracting and begin to relax, and the semilunar valves close due to the pressure of blood in the aorta.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 22 - Which of the following structures is not part of the conducting system of...

    Incorrect

    • Which of the following structures is not part of the conducting system of the heart?

      Your Answer:

      Correct Answer: Ventricular wall

      Explanation:

      The conduction system of the heart consists of the SA node, AV node, internodal pathway between these two nodes, Bundle of His and the purkinje fibers

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 23 - Endothelial cells produce the following substance(s): ...

    Incorrect

    • Endothelial cells produce the following substance(s):

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      Endothelial cells produce thromboxane, prostacyclins, nitric oxides, endothelins, IL-1 and TNF.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 24 - The end- diastolic ventricular volume is about? ...

    Incorrect

    • The end- diastolic ventricular volume is about?

      Your Answer:

      Correct Answer: 130 ml

      Explanation:

      The end diastolic volume in a healthy individual is about 130 ml.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 25 - Which of the following affects the magnitude of the action potential? ...

    Incorrect

    • Which of the following affects the magnitude of the action potential?

      Your Answer:

      Correct Answer: Changes in the external Na+ concentration

      Explanation:

      The magnitude of the action potential is determined by the sodium current. Increase in external sodium will result in increased influx of sodium and hence generation of a stronger action potential.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 26 - The following contributes to the rate of depolarization? ...

    Incorrect

    • The following contributes to the rate of depolarization?

      Your Answer:

      Correct Answer: All of the options given

      Explanation:

      Depolarization occurs due to impulses generated by the SA node. As the heart beats to the rhythm of the SA node, certain factors will effect the rate of depolarization. All the mentioned options effect the rate of depolarization.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 27 - Which of the atrial pressure changes represents the a-wave of the JVP ...

    Incorrect

    • Which of the atrial pressure changes represents the a-wave of the JVP

      Your Answer:

      Correct Answer: Atrial systole

      Explanation:

      The a-wave created on the venous pulse curve occurs as a result of atrial systole. Due to the pressure build-up in the atria, it causes a back pressure in the vena cava. This pressure is exerted on the valve and this back pressure is what causes a slight increase in the venous pressure.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 28 - Which of the following is true with AV nodal delay? ...

    Incorrect

    • Which of the following is true with AV nodal delay?

      Your Answer:

      Correct Answer: Shortened by sympathetic stimulation

      Explanation:

      AV nodal delay Is about 0.1s before the action potential spreads to the ventricles. It is shortened by stimulation of the sympathetic nervous system and lengthened by stimulation of the parasympathetic system.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 29 - Isovolumetric ventricular contraction lasts for? ...

    Incorrect

    • Isovolumetric ventricular contraction lasts for?

      Your Answer:

      Correct Answer: 0,05 s

      Explanation:

      Isovolumetric contraction lasts for about 0.05 seconds.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 30 - The coronary arteries fill during? ...

    Incorrect

    • The coronary arteries fill during?

      Your Answer:

      Correct Answer: Diastole

      Explanation:

      During systole the coronary arteries collapse as a result of the pressure due to contraction that is exerted on them. During diastole the heart muscle relaxes and the pressure on the coronary vessels is relieved allowing blood to flow through them to the subendocardium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Cardiovascular (1/5) 20%
Medicine (1/5) 20%
Passmed
Retry this test Dashboard