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  • Question 1 - A 27-year-old man presents with a regular tachycardia of 190 bpm. He is...

    Correct

    • A 27-year-old man presents with a regular tachycardia of 190 bpm. He is healthy and has no past medical history. Blood pressure and blood tests are all within normal parameters however the ECG confirms a narrow complex tachycardia. The tachycardia persists after giving IV adenosine 6mg. What should be the next step in management of this patient?

      Your Answer: IV 12mg adenosine

      Explanation:

      For narrow complex tachycardias with no compromise then vagal manoeuvres should be trialled first. The Valsalva manoeuvre should be the first vagal manoeuvre tried and works by increasing intra-thoracic pressure and affecting baroreceptors (pressure sensors) within the arch of the aorta. It is carried out by asking the patient to hold his/her breath while trying to exhale forcibly as if straining during a bowel movement. Adenosine, an ultra-short-acting AV nodal blocking agent, is indicated if vagal manoeuvres are not effective. Adenosine may be safely used during pregnancy. In adults the recommended first dose of intravenous adenosine is 6 mg. The dose is administered rapidly and then followed by a saline flush. Adenosine is only present in the circulation for about 5 seconds, so it is an excellent drug for diagnosis and treatment. If there was a response to adenosine but it was not long lasting, an additional dose of 12 mg of adenosine intravenously can be attempted. Doses greater than 12 mg are not recommended. If adenosine fails then Verapamil or a beta blocker can be used as alternatives. If the patient is hemodynamically unstable or other treatments have not been effective, synchronized electrical cardioversion may be used.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      17.4
      Seconds

  • Question 2 - Which of the following causes an increase in venous return? ...

    Correct

    • Which of the following causes an increase in venous return?

      Your Answer: An increase in the negative intra-thoracic pressure

      Explanation:

      During inspiration, intrathoracic pressure becomes more negative and intra-abdominal pressure more positive. This increases the venous pressure gradient from abdomen to thorax and promotes filling of the central veins.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      95.7
      Seconds

  • Question 3 - Which of the following supplies the AV node? ...

    Correct

    • Which of the following supplies the AV node?

      Your Answer: Right coronary artery

      Explanation:

      The AV node is supplied by the right coronary artery near the origin of the posterior IV artery.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      65.1
      Seconds

  • Question 4 - Vasodilatation of coronary arteries is caused by: ...

    Incorrect

    • Vasodilatation of coronary arteries is caused by:

      Your Answer: None of options provided

      Correct Answer: Hypoxia

      Explanation:

      The heart is highly metabolically active and boasts the highest oxygen consumption by mass of any organ. This demand for oxygen is met by the coronary circulation, which is responsible for delivering blood to the myocardium and represents approximately 5% of cardiac output. Vasodilation may be due to the local effect of hypoxia on coronary vessels, or local metabolic vasodilation, or the activation of β-adrenoceptors or some combination of these mechanisms.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      48.1
      Seconds

  • Question 5 - Myocyte action potentials – Choose the false statement: ...

    Incorrect

    • Myocyte action potentials – Choose the false statement:

      Your Answer: The plateau phase is due to Ca2+ influx

      Correct Answer: Repolarisation is due to net k+ influx

      Explanation:

      Final repolarization (phase 3) to the resting membrane potential (phase 4) is due to closure of the Ca2+ channels and a slow, delayed increase of K+ efflux through various types of K+ channels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      44.2
      Seconds

  • Question 6 - The isoforms of nitric oxide synthase which are found in the nervous system...

    Incorrect

    • The isoforms of nitric oxide synthase which are found in the nervous system (NOS1) and endothelial cells (NOS3) are activated by agents that increase which of the following intracellular electrolytes?

      Your Answer: Po4

      Correct Answer: Ca

      Explanation:

      Synthesis of nitric oxide is stimulated by activation of the NMDA receptors by certain agents. This leads to opening of the Calcium channels and an influx of calcium into the cell. This will activate the nitric oxide synthase. Nitric oxide is produced on demand.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      52
      Seconds

  • Question 7 - The celiac trunk consists of which arteries? ...

    Incorrect

    • The celiac trunk consists of which arteries?

      Your Answer:

      Correct Answer: Left gastric, common hepatic, splenic

      Explanation:

      The celiac trunk is the first major branch of the abdominal aorta. It is 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12). There are three main divisions of the celiac artery:- left gastric artery- common hepatic artery- splenic artery

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 8 - The rate of depolarisation of the sinus node membrane potential is modulated by...

    Incorrect

    • The rate of depolarisation of the sinus node membrane potential is modulated by all the following except:

      Your Answer:

      Correct Answer: Cardiac output

      Explanation:

      Cardiac output has no effect on the depolarization of the pacemaker potential of the heart.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 9 - Which of the following is true of the Natriuretic hormones? ...

    Incorrect

    • Which of the following is true of the Natriuretic hormones?

      Your Answer:

      Correct Answer: They are released in response to hypervolemia

      Explanation:

      Natriuretic hormones are vasodilators released in response to hypervolemia.

      Natriuretic hormones (NH) include three groups of compounds: the natriuretic peptides NPs (ANP, BNP and CNP), the gastrointestinal peptides (guanylin and uroguanylin), and endogenous cardiac steroids. These substances induce the kidney to excrete sodium and therefore participate in the regulation of sodium and water homeostasis, blood volume, and blood pressure (BP). In addition to their peripheral functions, these hormones act as neurotransmitters or neuromodulators in the brain.

      Atrial natriuretic peptide (ANP) plays a crucial role in blood pressure regulation by inducing natriuresis and diuresis in the kidney, inhibiting renin secretion, aldosterone production, and promoting vasorelaxation.  Two paracrine factors derived from endothelial cells play important roles in modulating ANP secretion. Endothelin, a potent vasoconstrictor, stimulates ANP secretion and augments stretch induced ANP secretion. The dramatic increase in ANP release produced by cardiac ischemia appears to be mediated in part by endothelin. Nitric oxide (NO), an important vasodilator, is also produced by endothelial cells and inhibits ANP secretion.

      Brain natriuretic peptide (BNP) shares ANP’s receptor but is primarily associated with antifibrotic effects in ventricular remodeling, serving as a biomarker for heart failure and myocardial infarction.

      C-type natriuretic peptide (CNP) acts locally in an autocrine/paracrine manner, exerting potent cardiovascular effects, including vasorelaxation and vascular remodeling post-injury. NPs also demonstrate diverse effects beyond cardiovascular and renal systems, such as bronchodilation, anti-inflammatory actions, and metabolic effects on adipose tissue and long bones.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 10 - In the Fick‘s method of measuring cardiac output, the arterial oxygen content can...

    Incorrect

    • In the Fick‘s method of measuring cardiac output, the arterial oxygen content can be measured in a sample obtained from

      Your Answer:

      Correct Answer: The pulmonary vein

      Explanation:

      In Fick’s original method, the following variables are measured:VO2, oxygen consumption in ml of pure gaseous oxygen per minute. This may be measured using a spirometer within a closed rebreathing circuit incorporating a CO2 absorberCa, the oxygen concentration of blood taken from the pulmonary vein (representing oxygenated blood)Cv, the oxygen concentration of blood from an intravenous cannula (representing deoxygenated blood)From these values, we know that:VO2 = (CO x Ca) – (CO x Cv)where CO = Cardiac Output, Ca = Oxygen concentration of arterial blood and Cv = Oxygen concentration of mixed venous blood.This allows us to sayCO = VO2/{Ca – Cv}and hence calculate cardiac output.Note that (Ca – Cv) is also known as the arteriovenous oxygen difference.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 11 - Activation of nitric oxide synthesis by endothelial cells is triggered by: ...

    Incorrect

    • Activation of nitric oxide synthesis by endothelial cells is triggered by:

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      Acetylcholine, histamine, bradykinin, vasoactive intestinal peptide (VIP) and shear stress on the endothelial cells causing the release of NO. NO is formed from arginine and causes vasodilatation of the blood vessels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 12 - 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 13 - Concerning coronary arteries, what is the net effect of B2 stimulation on the...

    Incorrect

    • Concerning coronary arteries, what is the net effect of B2 stimulation on the heart (e.g. Running athlete)?

      Your Answer:

      Correct Answer: Vasodilation via production of metabolites

      Explanation:

      The coronary arterioles contain α-adrenergic receptors, which cause vasoconstriction, and β-adrenergic receptors, which cause vasodilation. Activity in the noradrenergic nerves to the heart and injections of norepinephrine cause coronary vasodilation. However, norepinephrine also increases the heart rate and the force of cardiac contraction, and the vasodilation is due to production of vasodilator metabolites in the myocardium secondary to the increase in its activity. As exercise has the same effect as sympathetic stimulation, it will result in vasodilation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 14 - Coronary vasoconstriction can be caused by: ...

    Incorrect

    • Coronary vasoconstriction can be caused by:

      Your Answer:

      Correct Answer: Beta blockage

      Explanation:

      Coronary arteries contain alpha and beta receptors. The alpha receptor stimulates vasoconstriction and beta receptors stimulate vasodilation. When the chronotropic and inotropic effects of noradrenergic receptors are blocked by a B blocking drug, stimulation of the noradrenergic nerves will cause coronary vasoconstriction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 15 - Myocardial fibers have a resting membrane potential of approximately: ...

    Incorrect

    • Myocardial fibers have a resting membrane potential of approximately:

      Your Answer:

      Correct Answer: -90mv

      Explanation:

      The resting membrane potential of the mammalian heart is about -90 mv.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 16 - All of the following are consistent with the indicator dilution method except--- ...

    Incorrect

    • All of the following are consistent with the indicator dilution method except---

      Your Answer:

      Correct Answer: In thermodilution, the indicator used is warm saline

      Explanation:

      In thermodilution, the indicator used is cold saline.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 17 - Where would one normally find venous valves? ...

    Incorrect

    • Where would one normally find venous valves?

      Your Answer:

      Correct Answer: Saphenous vein

      Explanation:

      The intima of the limb veins is folded at intervals to form venous valves that prevent retrograde flow. There are no valves present in the very small veins, the great veins, or the veins in the brain and viscera.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 18 - Hyperkalaemia [K+ =7meq/l] can lead to the following ECG changes [Ca++ normal] ...

    Incorrect

    • Hyperkalaemia [K+ =7meq/l] can lead to the following ECG changes [Ca++ normal]

      Your Answer:

      Correct Answer: Peaked T waves

      Explanation:

      Hyperkalaemia causes the formation of tall tented T waves due to altered repolarization.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 19 - How many molecules of myosin attach to actin at any given time? ...

    Incorrect

    • How many molecules of myosin attach to actin at any given time?

      Your Answer:

      Correct Answer: 1

      Explanation:

      1 molecule of myosin binds to actin at any give time.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 20 - The postextrasystolic potentiation of myocardial contractility is due to: ...

    Incorrect

    • The postextrasystolic potentiation of myocardial contractility is due to:

      Your Answer:

      Correct Answer: Increase in intracellular Ca2+

      Explanation:

      The postextrasystolic potentiation of myocardial contractility Is not due to ventricular filling. It occurs in isolated locations in the heart and is due to increase availability of intracellular calcium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 21 - What is troponin? ...

    Incorrect

    • What is troponin?

      Your Answer:

      Correct Answer: A component of thin filaments

      Explanation:

      Skeletal muscle cytoplasmic proteins include myosin and actin (also known as thick and thin filaments, respectively) which are arranged in a repeating unit called a sarcomere. Troponin is a component of thin filaments (along with tropomyosin), and is the protein to which calcium binds.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 22 - Xanthines (for example Caffeine), exhibit their positive inotropic effect by: ...

    Incorrect

    • Xanthines (for example Caffeine), exhibit their positive inotropic effect by:

      Your Answer:

      Correct Answer: Inhibiting the breakdown cAMP

      Explanation:

      Xanthines exert their positive inotropic effect by inhibiting the breakdown of the cAMP resulting in stronger and sustained contraction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 23 - Preload: ...

    Incorrect

    • Preload:

      Your Answer:

      Correct Answer: Is the degree to which the myocardium is stretched before is contracts

      Explanation:

      Preload is end diastolic volume. It is the degree to which the heart muscle fiber is stretched when it fills up completely just before the heart contracts.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 24 - Which of the following has the shortest duration: ...

    Incorrect

    • Which of the following has the shortest duration:

      Your Answer:

      Correct Answer: Atrial systole

      Explanation:

      Atrial systole: 0.1s

      Atrial diastole: around 0.4s

      Ventricular diastole: 0.4-0.53s

      Ventricular systole: 0.27s

      PR interval: 0.12-0.2 s

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 25 - The initial rapid depolarization in the action potential of cardiac muscle cells is...

    Incorrect

    • The initial rapid depolarization in the action potential of cardiac muscle cells is due to:

      Your Answer:

      Correct Answer: Opening of voltage-gated Na+ channels

      Explanation:

      The initial depolarization of the action potential in a cardiac muscle cell is due to the sodium current generated by opening of the voltage gated sodium channels leading to an influx of sodium ions into the cell and raising the membrane potential towards threshold.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 26 - Which factors increase the end-diastolic volume? ...

    Incorrect

    • Which factors increase the end-diastolic volume?

      Your Answer:

      Correct Answer: Constriction of veins

      Explanation:

      End diastolic volume is also known as preload. It is the amount of blood the heart contracts against. Constriction of veins will decrease venous pooling and increase venous return, hence increasing the end diastolic volume. Standing will increase venous pooling hence decreasing venous return and end diastolic volume. Raised intrapericardial pressure will also decrease venous return and hence end diastolic volume.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 27 - Which of the following pairs are correct concerning arteriolar tone? ...

    Incorrect

    • Which of the following pairs are correct concerning arteriolar tone?

      Your Answer:

      Correct Answer: Hormonal control: catecholamines affect the adrenergic receptors of the vascular smooth muscle

      Explanation:

      Catecholamines released from the adrenal medulla act on the noradrenergic receptors of the vascular smooth muscles. In the skeletal muscles and liver it causes vasodilation whilst it causes vasoconstriction in the rest of the blood vessels of the body.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 28 - Which of the following does not contribute to increased stroke volume during exercise?...

    Incorrect

    • Which of the following does not contribute to increased stroke volume during exercise?

      Your Answer:

      Correct Answer: Increased length of filling time during diastole

      Explanation:

      Prolonged aerobic exercise training may also increase stroke volume, which frequently results in a lower (resting) heart rate. Reduced heart rate prolongs ventricular diastole (filling), increasing end-diastolic volume, and ultimately allowing more blood to be ejected.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 29 - The process by which depolarization of the muscle fiber initiates contraction is called?...

    Incorrect

    • The process by which depolarization of the muscle fiber initiates contraction is called?

      Your Answer:

      Correct Answer: Action potential

      Explanation:

      This process is known as an action potential. Upon generation of an action potential when depolarization reaches threshold, it spreads throughout the muscle fiber, resulting in generation of an excitation-contraction coupling leading to contraction of the muscle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 30 - In ventricular fibrillation (VF), the first defibrillation attempt (with a biphasic defibrillator) should...

    Incorrect

    • In ventricular fibrillation (VF), the first defibrillation attempt (with a biphasic defibrillator) should be made at:

      Your Answer:

      Correct Answer: 200 J

      Explanation:

      Defibrillation is a common treatment for life-threatening cardiac dysrhythmias and ventricular fibrillation. If the patient is in Ventricular tachycardia (VT) or ventricular fibrillation (VF) on the monitor, immediately apply the pads and shock the patient with 120-200 Joules on a biphasic defibrillator or 360 Joules on a monophasic defibrillator.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 31 - 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 32 - Which one of the following is a cause of a soft second heart...

    Incorrect

    • Which one of the following is a cause of a soft second heart sound?

      Your Answer:

      Correct Answer: Aortic stenosis

      Explanation:

      Second heart sound (S2) forms the dub of lub-dub and is composed of components A2 and P2. •    loud: hypertension•    soft: AS•    fixed split: physiological split (normally occurs during inhalation), right bundle branch block, pulmonary stenosis, and atrial septal defect.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 33 - 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 34 - Concerning surface anatomy, where is the base of the heart ...

    Incorrect

    • Concerning surface anatomy, where is the base of the heart

      Your Answer:

      Correct Answer: 2nd left costal to 3rd right costal cartilage

      Explanation:

      The base of the heart, also known as the superior border of the heart corresponds to a line connecting the inferior border of the 2nd left costal cartilage to the superior border of the 3rd right costal cartilage.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 35 - Heart rate can be slowed by: ...

    Incorrect

    • Heart rate can be slowed by:

      Your Answer:

      Correct Answer: Grief

      Explanation:

      Grief stimulates the parasympathetic nervous system, resulting in a decrease in the heart rate.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 36 - What is a characteristic findings on ECG in hyperkalaemia? ...

    Incorrect

    • What is a characteristic findings on ECG in hyperkalaemia?

      Your Answer:

      Correct Answer: Tall, tented T waves

      Explanation:

      Hyperkalaemia leads to:

      – Prolonged PR interval

      – Small P waves

      – Tall, tented T waves

      – Widened QRS complexes and eventually asystole.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 37 - The right border of the heart corresponds to which line on the surface...

    Incorrect

    • The right border of the heart corresponds to which line on the surface of the chest?

      Your Answer:

      Correct Answer: Line drawn from the 3rd right costal cartilage to the 6th right costal cartilage

      Explanation:

      The right border corresponds to a line drawn from the 3rd right costal cartilage to the 6th right costal cartilage; this border is slightly convex to the right.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 38 - The major factor in controlling coronary artery blood flow is considered to be?...

    Incorrect

    • The major factor in controlling coronary artery blood flow is considered to be?

      Your Answer:

      Correct Answer: Metabolites of oxygen consumption

      Explanation:

      There is a strong relationship between myocardial blood flow and oxygen consumption. This indicates that products of metabolism may cause vasodilation of the coronary artery.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 39 - 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 40 - Calcium needed for cardiac muscle contraction is made available during which phase of...

    Incorrect

    • Calcium needed for cardiac muscle contraction is made available during which phase of the action potential?

      Your Answer:

      Correct Answer: 2

      Explanation:

      It is made available during the plateau phase of the action potential i.e. phase 2. During the plateau phase of the action potential, Calcium from the extracellular fluid enters through the L type of calcium channels. This entry triggers the release of more calcium from the sarcoplasmic reticulum via the ryanodine receptors.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 41 - Which of the following makes up the thick filaments in muscle fibers? ...

    Incorrect

    • Which of the following makes up the thick filaments in muscle fibers?

      Your Answer:

      Correct Answer: Myosin

      Explanation:

      The thick filaments are made up of myosin and the thin filaments are made up of actin. The thick filaments are twice the size of the thin filaments and are aligned to form the A band. The thin filaments extending out from the A band form the less dense I bands.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 42 - 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 43 - Coronary flow is reduced during ...

    Incorrect

    • Coronary flow is reduced during

      Your Answer:

      Correct Answer: Tachycardia

      Explanation:

      Maximum amount of blood flow in the coronary arteries occur during diastole. When the heart rate increases which is also called tachycardia the duration of diastole decreases. Hence the amount of blood flow to the cardiac muscle also decreases.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 44 - Which of the following factors serve to decrease cardiac output? ...

    Incorrect

    • Which of the following factors serve to decrease cardiac output?

      Your Answer:

      Correct Answer: Standing from a lying position

      Explanation:

      Sleep has no effect on the cardiac output. Anxiety, excitement, increased body temperature and pregnancy will increase the cardiac output. Standing from a lying position will decrease the cardiac output transiently.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 45 - Which of the following concerning PR interval is INCORRECT? ...

    Incorrect

    • Which of the following concerning PR interval is INCORRECT?

      Your Answer:

      Correct Answer: Always measured from the beginning of p wave to the beginning of r wave

      Explanation:

      The PR interval measures the time from the start of atrial depolarization to the start of ventricular depolarization. The PR interval is only measured from the beginning of P wave to beginning of R wave if the Q wave is absent.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 46 - 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 47 - Blood flow to the subendocardial portions of the left ventricular muscle occurs mainly...

    Incorrect

    • Blood flow to the subendocardial portions of the left ventricular muscle occurs mainly during:

      Your Answer:

      Correct Answer: Diastole

      Explanation:

      The sub endocardium receives the least amount of blood from the coronary arteries. During systole the coronary arteries collapse as a result of the pressure from 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 sub endocardium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 48 - The V wave in the jugular pulse is caused by: ...

    Incorrect

    • The V wave in the jugular pulse is caused by:

      Your Answer:

      Correct Answer: Atrial filling

      Explanation:

      The v wave reflects the passive increase in pressure and volume of the right atrium as it fills in late systole and early diastole.

      The jugular vein pulsations usually have two elevations and two troughs. The first elevation (a wave) corresponds to the slight rise in atrial pressure resulting from atrial contraction. The first descent (x descent) reflects a fall in atrial pressure that starts with atrial relaxation. The second elevation (v wave) corresponds to ventricular systole when blood is entering the right atrium from the vena cavae while the tricuspid valve is closed. Finally, the second descent (y descent) reflects falling right atrial pressure as the tricuspid valve opens and blood drains from the atrium into the ventricle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 49 - Coronary arteries arise from? ...

    Incorrect

    • Coronary arteries arise from?

      Your Answer:

      Correct Answer: None of the above

      Explanation:

      Coronary arteries arise from the sinuses behind 2 of the cusps of the aortic valve at the root of aorta.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 50 - When the heart rate is increased (to pathological levels) which of the following...

    Incorrect

    • When the heart rate is increased (to pathological levels) which of the following is correct when comparing the duration of diastole to systole?

      Your Answer:

      Correct Answer: It is shortened to a greater degree

      Explanation:

      The duration of systole is more fixed than the duration of diastole. When the heart rate increases the timing of the systole remains more or less the same however diastole decreases.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 51 - Direct conduction from the atrium to the ventricles is prevented by: ...

    Incorrect

    • Direct conduction from the atrium to the ventricles is prevented by:

      Your Answer:

      Correct Answer: Annulus fibrosus

      Explanation:

      The annulus fibrosus disconnects the syncytium complex. The atria are rapidly activated however the activation peters out when the insulating layer-the annulus fibrosus-is reached.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 52 - Myocardial oxygen consumption is increased by: ...

    Incorrect

    • Myocardial oxygen consumption is increased by:

      Your Answer:

      Correct Answer: An increase in after load

      Explanation:

      Cardiac oxygen consumption is directly related to the amount of tension that develops in the ventricles. It is increased by an increased size of heart, increased afterload, increased contractility and increased heart rate.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 53 - Cross-bridges between actin and myosin filaments contain: ...

    Incorrect

    • Cross-bridges between actin and myosin filaments contain:

      Your Answer:

      Correct Answer: Calcium ions

      Explanation:

      At rest troponin I is bound to actin and tropomyosin and covers the site where the myosin head interacts with actin. When calcium enters into the muscle, it binds with troponin C and causes a structural change in troponin I which moves out of the myosin binding site and causes the cross bridges between the actin and myosin filaments to occur.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 54 - In the blood supply of the heart, ‘dominance’ refers to the coronary artery...

    Incorrect

    • In the blood supply of the heart, ‘dominance’ refers to the coronary artery which supplies the?

      Your Answer:

      Correct Answer: Posterior interventricular artery

      Explanation:

      Dominance of the coronary artery system is defined by the artery that gives rise to the posterior interventricular artery. Dominance of the right coronary artery is more common (68%). It gives rise to the large posterior interventricular branch which goes down to the apex of the heart.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 55 - With regard to the endothelial structure, the epithelium constitute: ...

    Incorrect

    • With regard to the endothelial structure, the epithelium constitute:

      Your Answer:

      Correct Answer: Simple squamous

      Explanation:

      The single layer of squamous epithelium lining the heart and blood vessels is known as the endothelium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 56 - The bradycardia that occurs in patients with raised intracranial pressure is a result...

    Incorrect

    • The bradycardia that occurs in patients with raised intracranial pressure is a result of the?

      Your Answer:

      Correct Answer: Cushing reflex

      Explanation:

      When intracranial pressure is increased, the blood supply to RVLM neurons is compromised. This results in an increase in their discharge as a result of hypoxia and hypercapnia. The resultant rise in systemic arterial pressure (Cushing reflex) tends to restore the blood flow to the medulla.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 57 - Most of the venous blood returns to the heart through the: ...

    Incorrect

    • Most of the venous blood returns to the heart through the:

      Your Answer:

      Correct Answer: Coronary sinus and anterior cardiac veins

      Explanation:

      Most of the venous blood returns to the heart via the coronary sinus and the anterior cardiac veins which drain into the right atrium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 58 - Which is the commonest cardiovascular abnormality seen in an adult patient with Marfan’s...

    Incorrect

    • Which is the commonest cardiovascular abnormality seen in an adult patient with Marfan’s syndrome?

      Your Answer:

      Correct Answer: Aortic aneurysm

      Explanation:

      Marfan syndrome (MFS) is a genetic disorder of connective tissue. The degree to which people are affected varies. People with Marfan’s tend to be tall, and thin, with long arms, legs, fingers and toes. They also typically have flexible joints and scoliosis. The most serious complications involve the heart and aorta with an increased risk of mitral valve prolapse and aortic aneurysm.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 59 - Where are the baroreceptors of the great arteries located? ...

    Incorrect

    • Where are the baroreceptors of the great arteries located?

      Your Answer:

      Correct Answer: In the adventitia

      Explanation:

      Arterial baroreceptors are located in the aortic arch and carotid sinuses, and are formed by small nerve endings present in the adventitia of these vessels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 60 - Concerning surface anatomy, where is the apex beat found? ...

    Incorrect

    • Concerning surface anatomy, where is the apex beat found?

      Your Answer:

      Correct Answer: 5th intercostal space mid clavicular line

      Explanation:

      The location of the apex beat may vary but it is mostly found in the left 5th intercostal space 6 cm from the anterior median line or in the mid clavicular line.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 61 - Which of the following statements is true regarding pulsus alternans? ...

    Incorrect

    • Which of the following statements is true regarding pulsus alternans?

      Your Answer:

      Correct Answer: It is found in association with a third heart sound

      Explanation:

      Pulsus alternans is a physical finding with arterial pulse waveform showing alternating strong and weak beats. It is almost always indicative of left ventricular systolic impairment, and carries a poor prognosis. A pathological third heart sound is usually associated.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 62 - Which statement about the 2nd heart sound is true? ...

    Incorrect

    • Which statement about the 2nd heart sound is true?

      Your Answer:

      Correct Answer: It is caused by closure of the aortic and pulmonary valves.

      Explanation:

      The second heart sound is produced due to closure of the aortic and pulmonary valves. It is a high pitched dub sound.

      Normally the aortic closure sound (A2) occurs prior to the pulmonic closure sound (P2), and the interval between the two (splitting) widens on inspiration and narrows on expiration. With quiet respiration, A2 will normally precede P2 by 0.02 to 0.08 second (mean, 0.03 to 0.04 sec) with inspiration. In younger subjects inspiratory splitting averages 0.04 to 0.05 second during quiet respiration. With expiration, A2 and P2 may be superimposed and are rarely split as much as 0.04 second. If the second sound is split by greater than 0.04 second on expiration, it is usually abnormal. Therefore, the presence of audible splitting during expiration (i.e., the ability to hear two distinct sounds during expiration) is of greater significance at the bedside in identifying underlying cardiac pathology than is the absolute inspiratory increase in the A2–P2 interval.

      The respiratory variation of the second heart sound can be categorized as follows: (1) normal (physiologic) splitting; (2) persistent (audible expiratory) splitting, with normal respiratory variation; (3) persistent splitting without respiratory variation (fixed splitting); and (4) reversed (paradoxical) splitting.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 63 - Water hammer pulse is found in: ...

    Incorrect

    • Water hammer pulse is found in:

      Your Answer:

      Correct Answer: Aortic insufficiency

      Explanation:

      Watson’s water hammer pulse is the medical sign which describes a pulse that is bounding and forceful, rapidly increasing and subsequently collapsing, as if it were the sound of a water hammer that was causing the pulse. A water hammer was a Victorian toy in which a tube was half filled with fluid, the remainder being a vacuum. The child would invert and reinvert the tube; each time the impact of the fluid at each end would sound like a hammer blow. This is associated with increased stroke volume of the left ventricle and decrease in the peripheral resistance leading to the widened pulse pressure of aortic regurgitation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 64 - Which of the following is first to rise following myocardial infarction? ...

    Incorrect

    • Which of the following is first to rise following myocardial infarction?

      Your Answer:

      Correct Answer: Myoglobin

      Explanation:

      Myoglobin, is a sensitive indicator of muscle injury and is first to rise following MI within two hours but is nonspecific.Troponin and CK-MB both begin to rise approximately three hours after MI. The cardiac troponins T and I which are released within 4–6 hours of an attack of MI and remain elevated for up to 2 weeks, have nearly complete tissue specificity and are now the preferred markers for assessing myocardial damage.Lactate dehydrogenase (LDH) begins to rise approximately 12 hours after MI.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 65 - 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 66 - Nitric oxide triggers vascular smooth muscle contraction through activation of which enzyme? ...

    Incorrect

    • Nitric oxide triggers vascular smooth muscle contraction through activation of which enzyme?

      Your Answer:

      Correct Answer: Guanylyl cyclase

      Explanation:

      Impaired production or excess catabolism of NO impairs this endothelium-dependent vasodilator function and may contribute to excessive vasoconstriction under various pathological situations.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 67 - Depolarization of the T tubule membrane activates the sarcoplasmic reticulum via which receptors?...

    Incorrect

    • Depolarization of the T tubule membrane activates the sarcoplasmic reticulum via which receptors?

      Your Answer:

      Correct Answer: Dihydropyridine receptors

      Explanation:

      Action potentials are transmitted to the fibrils of a fiber through the T tubule system. It triggers the release of Ca 2+ form the terminal cisterns. Depolarization of the T tubules activates the sarcoplasmic reticulum through the dihydropyridine receptors.

      Dihydropyridine receptors (DHPRs), are voltage-gated Ca2+ channels, and ryanodine receptors (RyRs), which are intracellular Ca2+ release channels, are expressed in diverse cell types, including skeletal and cardiac muscle.

      Ryanodine receptors (RyRs) are located in the sarcoplasmic/endoplasmic reticulum membrane and are responsible for the release of Ca2+ from intracellular stores during excitation-contraction coupling in both cardiac and skeletal muscle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 68 - 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 69 - The ‘c’ wave in JVP corresponds more closely with: ...

    Incorrect

    • The ‘c’ wave in JVP corresponds more closely with:

      Your Answer:

      Correct Answer: Isovolumetric contraction

      Explanation:

      The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the venous system via visualization of the internal jugular vein. It can be useful in the differentiation of different forms of heart and lung disease. Classically three upward deflections (peaks) and two downward deflections (troughs) have been described:The upward deflections are the a (atrial contraction), c (ventricular contraction and resulting bulging of tricuspid into the right atrium during isovolumetric systole) and v = venous filling.The downward deflections of the wave are the x (the atrium relaxes and the tricuspid valve moves downward) and the y descent (filling of ventricle after tricuspid opening).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 70 - Xanthines such as caffeine and theophylline are positively inotropic due to: ...

    Incorrect

    • Xanthines such as caffeine and theophylline are positively inotropic due to:

      Your Answer:

      Correct Answer: Inhibition of cAMP breakdown

      Explanation:

      Xanthines exert their positive inotropic effect by inhibiting the breakdown of the cAMP resulting in stronger and sustained contractions.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 71 - Initial depolarization of cardiac muscle is due to influx of: ...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 72 - Concerning surface anatomy, where is the aortic valve found? ...

    Incorrect

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

      Your Answer:

      Correct Answer: Situated in the left third intercostal space underneath the sternum

      Explanation:

      The aortic valve is situated in the left 3rd intercostal space just beneath the sternum.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 73 - Which coronary artery supplies the right atria? ...

    Incorrect

    • Which coronary artery supplies the right atria?

      Your Answer:

      Correct Answer: Right coronary

      Explanation:

      The left coronary artery distributes blood to the left side of the heart, the left atrium and ventricle, and the interventricular septum. The circumflex artery arises from the left coronary artery and follows the coronary sulcus to the left. Eventually, it will fuse with the small branches of the right coronary artery. The right coronary artery proceeds along the coronary sulcus and distributes blood to the right atrium, portions of both ventricles, and the heart conduction system.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 74 - The amount of a substance taken up by an organ (or whole body)...

    Incorrect

    • The amount of a substance taken up by an organ (or whole body) per unit time is = (the arterial level - the venous level) * the blood flow. This statement describes?

      Your Answer:

      Correct Answer: The Fick principle

      Explanation:

      The essence of the Fick principle is that blood flow to an organ can be calculated using a marker substance if the following information is known:- Amount of marker substance taken up by the organ per unit time- Concentration of marker substance in arterial blood supplying the organ- Concentration of marker substance in venous blood leaving the organ

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 75 - Which of the following does not lower ventricular rate in atrial fibrillation? ...

    Incorrect

    • Which of the following does not lower ventricular rate in atrial fibrillation?

      Your Answer:

      Correct Answer: Adrenaline

      Explanation:

      Adrenaline is a sympathetic neurotransmitter which increases the heart rate. During atrial fibrillation the atria is contracting at more than 200 beats/min. Acetylcholine is a parasympathetic neurotransmitter decreasing the heart rate. Digital also depresses the conduction at the AV conduction. Vagal discharge and occulocardiac reflux decrease the heart rate and convert the tachycardia into normal sinus rhythm.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 76 - Which vaso metabolite decreases coronary blood flow? ...

    Incorrect

    • Which vaso metabolite decreases coronary blood flow?

      Your Answer:

      Correct Answer: Endothelin

      Explanation:

      Decreased O2, increased CO2, lactate, prostaglandins, adenine nucleotides, adenosine, H+, K+ and cyanide produce vasodilation and thus an increase in coronary blood flow.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 77 - The following is true in relation to coronary venous drainage? ...

    Incorrect

    • The following is true in relation to coronary venous drainage?

      Your Answer:

      Correct Answer: Most venous return ultimately drains into right atrium via the coronary sinus

      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

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 78 - Factors influencing cardiac output include which of the following? ...

    Incorrect

    • Factors influencing cardiac output include which of the following?

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      There is a correlation between resting CO and body surface area. The output per min per square meter of body surface (the cardiac index) averages 3.2l.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 79 - Which of the following conditions does not influence the cardiac output? ...

    Incorrect

    • Which of the following conditions does not influence the cardiac output?

      Your Answer:

      Correct Answer: Sleep

      Explanation:

      Sleep has no effect on the cardiac output.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 80 - How does pregnancy affect the cardiac output of a patient? ...

    Incorrect

    • How does pregnancy affect the cardiac output of a patient?

      Your Answer:

      Correct Answer: Increased cardiac output due to increase in heart rate and stroke volume

      Explanation:

      Cardiac Output increases to a similar degree as the blood volume. During the first trimester cardiac output is 30-40% higher than in the non-pregnant state. Steady rises are shown on Doppler echocardiography, from an average of 6.7 litres/minute at 8-11 weeks to about 8.7 litres/minute flow at 36-39 weeks; they are due, primarily, to an increase in stroke volume (35%) and, to a lesser extent, to a more rapid heart rate (15%). There is a steady reduction in systemic vascular resistance (SVR) which contributes towards the hyperdynamic circulation observed in pregnancy

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 81 - Where on the surface of the chest is the normal site of auscultation...

    Incorrect

    • Where on the surface of the chest is the normal site of auscultation for the mitral area?

      Your Answer:

      Correct Answer: 4th left intercostal space in the mid-clavicular line

      Explanation:

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

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 82 - The approximate incidence of deep venous thrombosis (DVT) in the general population each...

    Incorrect

    • The approximate incidence of deep venous thrombosis (DVT) in the general population each year is:

      Your Answer:

      Correct Answer: 1 per 1000

      Explanation:

      About 1 in 1000 adults per year has DVT, but as of 2011, available data is dominated by North American and European populations. DVT is rare in children, with an incidence of about 1 in 100,000 a year. From childhood to old age, incidence increases by a factor of about 1000, with almost 1% of the elderly experiencing DVTs yearly.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 83 - The Wiebel-Palade body found in the endothelial cells is responsible for the production...

    Incorrect

    • The Wiebel-Palade body found in the endothelial cells is responsible for the production and release of which factor?

      Your Answer:

      Correct Answer: Von Willebrand factor

      Explanation:

      Weibel-Palade bodies are the storage granules of endothelial cells, the cells that form the inner lining of the blood vessels and heart. They store and release two principal molecules, von Willebrand factor and P-selectin, and thus play a dual role in haemostasis and inflammation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 84 - 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:

      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
      0
      Seconds

  • Question 85 - Calcium induced calcium release occurs in the sarcoplasmic reticulum by activation of which...

    Incorrect

    • Calcium induced calcium release occurs in the sarcoplasmic reticulum by activation of which receptors

      Your Answer:

      Correct Answer: Ryanodine receptors

      Explanation:

      Calcium-induced calcium release (CICR) describes a biological process whereby calcium is able to activate calcium release from intracellular Ca2+ stores (e.g., endoplasmic reticulum or sarcoplasmic reticulum). CICR occurs when the resulting Ca2+ influx activates ryanodine receptors on the SR membrane, which causes more Ca2+ to be released into the cytosol.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 86 - In a normal heart rate at rest, the left ventricular end-diastolic volume is...

    Incorrect

    • In a normal heart rate at rest, the left ventricular end-diastolic volume is ….

      Your Answer:

      Correct Answer: 100-130 ml

      Explanation:

      In cardiovascular physiology, end-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole. Because greater EDVs cause greater distention of the ventricle, EDV is often used synonymously with preload, which refers to the length of the sarcomeres in cardiac muscle prior to contraction (systole). End-diastolic volume: Right = 144 mL(± 23mL) & Left = 142 mL (± 21 mL).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 87 - Cholinergic vagal supply to the SA and AV nodes results in slowing of...

    Incorrect

    • Cholinergic vagal supply to the SA and AV nodes results in slowing of the heart rate via:

      Your Answer:

      Correct Answer: M2 muscarinic receptors

      Explanation:

      M2 muscarinic receptors are the receptors for the parasympathetic system to the SA and the AV node.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 88 - Which of the following conditions has no effect on cardiac output? ...

    Incorrect

    • Which of the following conditions has no effect on cardiac output?

      Your Answer:

      Correct Answer: Sleep

      Explanation:

      Sleep has no effect on the cardiac output. Anxiety, excitement and pregnancy will increase the cardiac output. Standing from a lying position will decrease the cardiac output transiently.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 89 - Which of the following corresponds to an oblique line drawn from the sternal...

    Incorrect

    • Which of the following corresponds to an oblique line drawn from the sternal end of the left 3rd costal cartilage to the sternal end of the right 6th costal cartilage?

      Your Answer:

      Correct Answer: Atrio-ventricular (coronary) groove

      Explanation:

      The AV groove corresponds to the right border of the heart. The right border corresponds to a line drawn from the 3rd right costal cartilage to the 6th right costal cartilage; this border is slightly convex to the right.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 90 - The basic unit of contraction in myocytes is: ...

    Incorrect

    • The basic unit of contraction in myocytes is:

      Your Answer:

      Correct Answer: Sarcomere

      Explanation:

      Sarcomere is the organelle where calcium is stored to be released during contraction of the muscle. It is the basic unit of contraction in striated muscle fibers. As myocytes are also striated muscles, sarcomeres also forms the basic unit of contraction. The impulses travel along the membrane and via its interaction with the dihydropyridine receptors it releases the stored calcium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Cardiovascular (3/6) 50%
Medicine (3/6) 50%
Passmed
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