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

  • Question 1 - The positive inotropic effect of digoxin is due to? ...

    Correct

    • The positive inotropic effect of digoxin is due to?

      Your Answer: Inhibition of the sodium potassium ATPase in the myocardium

      Explanation:

      Digitalis compounds are potent inhibitors of cellular Na+/K+-ATPase. This ion transport system moves sodium ions out of the cell and brings potassium ions into the cell. By inhibiting the Na+/K+-ATPase, cardiac glycosides cause the intracellular sodium concentration to increase. This then leads to an accumulation of intracellular calcium via the Na+/Ca++ exchange system. In the heart, increased intracellular calcium causes more calcium to be released by the sarcoplasmic reticulum, thereby making more calcium available to bind to troponin-C, which increases contractility (inotropy).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      13.3
      Seconds

  • Question 2 - The function of Troponin T in cardiac muscle is? ...

    Incorrect

    • The function of Troponin T in cardiac muscle is?

      Your Answer: Escape into the circulation during acute coronary syndrome to allow for a diagnosis of NSTEMI

      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
      19.7
      Seconds

  • Question 3 - In a 30 year old male with hypertrophic obstructive cardiomyopathy (HOCM), which of...

    Incorrect

    • In a 30 year old male with hypertrophic obstructive cardiomyopathy (HOCM), which of the following is associated with increased risk of sudden death?

      Your Answer: Asymmetrical septal hypertrophy

      Correct Answer: Degree of left ventricular hypertrophy

      Explanation:

      Hypertrophic cardiomyopathy (HCM) is a disease in which a portion of the myocardium (heart muscle) is enlarged without any obvious cause, creating functional impairment of the heart. It is the leading cause of sudden death in young athletes. Major risk factors for sudden death in individuals with HCM include prior history of cardiac arrest or ventricular fibrillation, spontaneous sustained ventricular tachycardia, family history of premature sudden death, unexplained syncope, left ventricular thickness greater than or equal to 30 mm, abnormal exercise blood pressure and unsustained ventricular tachycardia. The most strongly correlated is the degree of left ventricular hypertrophy (LVH).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      39.8
      Seconds

  • Question 4 - Depolarization spreads rapidly through cardiac muscle fibers because of the presence of: ...

    Incorrect

    • Depolarization spreads rapidly through cardiac muscle fibers because of the presence of:

      Your Answer: Tight junctions

      Correct Answer: Gap junctions

      Explanation:

      The cardiac muscles have gap junctions in between the cells. They allow for the formation of low resistance passages, which allow ions to diffuse through every muscle fiber rapidly and result in the cardiac muscles functioning as a syncytium, without any protoplasmic bridges involved.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      6.5
      Seconds

  • Question 5 - What is the isolated effect of B2 stimulation on the coronaries. ...

    Incorrect

    • What is the isolated effect of B2 stimulation on the coronaries.

      Your Answer: No effect net effect

      Correct Answer: Vasodilatation

      Explanation:

      Norepinephrine and epinephrine are agonists for all adrenergic receptor subtypes, although with varying affinities. Based on their physiology and pharmacology, adrenergic receptors have been divided into two principal types: alpha and beta. These types have been further differentiated into alpha-1, alpha-2, b1, and b2 receptors. Alpha-1 Receptors are located on postsynaptic cells in smooth muscle and elicit vasoconstriction. alpha-2 Receptors are localized on presynaptic membranes of postganglionic nerve terminals that synthesize norepinephrine. When activated by catecholamines, alpha-2 receptors act as negative feedback controllers, inhibiting further norepinephrine release. Activation of myocardial b1 receptors stimulates the rate and strength of cardiac contraction, and consequently increases cardiac output. b1 Receptor activation also stimulates renin release from the kidney. Another class of antihypertensive agents acts by inhibiting b1 receptors. Activation of b2 receptors by epinephrine relaxes vascular smooth muscle and results in vasodilation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      50.5
      Seconds

  • Question 6 - Xanthines (for example Caffeine), exhibit their positive inotropic effect by: ...

    Incorrect

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

      Your Answer: Stimulation of b1-adrenergic receptors

      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
      12.3
      Seconds

  • Question 7 - 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 8 - According to Starling's law of the heart: ...

    Incorrect

    • According to Starling's law of the heart:

      Your Answer:

      Correct Answer: The extent of the preload is proportional to the end-diastolic volume

      Explanation:

      Frank starlings law describes that an increase in the venous return or the end diastolic volume will cause an increase in the stroke volume/ preload and also cardiac output. It stems from the fact that increased venous return will increase the stretch on the ventricular muscle fibers. The sarcomere will stretch a considerable length that is needed for maximum contraction and the development of tension in the muscle fiber. The greater the venous return the greater the cardiac output. This relationship is directly proportional.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 9 - 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 10 - What is the function of the BK channel on the vascular smooth muscle...

    Incorrect

    • What is the function of the BK channel on the vascular smooth muscle membrane?

      Your Answer:

      Correct Answer: Massive K+ influx, increasing membrane potential, and shutting off the voltage gated Ca2+ channel

      Explanation:

      In vascular smooth muscles, Ca2+ influx via the voltage gated calcium channels increases the cytosolic calcium, as well as causing release of calcium from the sarcoplasmic reticulum. The high calcium concentration increases the activity of the calcium activated potassium channels. These are known as BK channels. Massive influx of potassium shuts off the voltage gated calcium channels and causes relaxation of the vascular smooth muscle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 11 - The following are examples of the functions of the vascular endothelium except— ...

    Incorrect

    • The following are examples of the functions of the vascular endothelium except—

      Your Answer:

      Correct Answer: Tumour suppression

      Explanation:

      Vascular endothelium has many important functions including regulation of vascular tone, molecular exchange between blood and tissue compartments, hemostasis and signaling for the immune regulation and inflammation. Depending on specific tissue needs and local stresses, endothelial cells are capable of evoking either antithrombotic or prothrombotic events. A tumor suppression is related to genes, or anti-oncogenes, that regulate a cell during cell division and replication.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 12 - Which of the following antiarrhythmic drugs may be used in the treatment of...

    Incorrect

    • Which of the following antiarrhythmic drugs may be used in the treatment of long QT syndrome?

      Your Answer:

      Correct Answer: Atenolol

      Explanation:

      Beta-blockers are the mainstay of treatment in long QT syndrome. Implantable cardioverter-defibrillators are the most effective treatment in genotypes with a high risk of recurrence.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 13 - 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 14 - 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. They are voltage gated calcium channels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 15 - 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 16 - Regarding cardiac contractility, catecholamines exert their inotropic effect via: ...

    Incorrect

    • Regarding cardiac contractility, catecholamines exert their inotropic effect via:

      Your Answer:

      Correct Answer: Î’1-adrenergic receptors and gs

      Explanation:

      Catecholamines exert their inotropic effect on the heart via the B1 adrenergic receptors and Gs, stimulating adenyl cyclase and increasing the production of cAMP.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 17 - Which vagus nerve mainly supplies the AV node? ...

    Incorrect

    • Which vagus nerve mainly supplies the AV node?

      Your Answer:

      Correct Answer: Left vagus

      Explanation:

      As the AV node develops from the left side of the embryo It is supplied by the left vagus nerve.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 18 - Excitation-contraction coupling in cardiac muscle involves all of the following except: ...

    Incorrect

    • Excitation-contraction coupling in cardiac muscle involves all of the following except:

      Your Answer:

      Correct Answer: Binding of Ca2+ to calmodulin

      Explanation:

      In the excitation contraction coupling model, an action potential is transmitted to the fibrils of a fiber through the T tubule system. It triggers the release of Ca 2+ from the terminal cisterns. Depolarization of the T tubules activates the sarcoplasmic reticulum through the dihydropyridine receptors. These are voltage gates calcium channels. Calcium binds to calmodulin during contraction of the smooth muscle and not the cardiac muscles.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 19 - 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 20 - 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 21 - Which of the following best describes the cardiac muscle? ...

    Incorrect

    • Which of the following best describes the cardiac muscle?

      Your Answer:

      Correct Answer: Striated and involuntary

      Explanation:

      Cardiac muscle (heart muscle) is an involuntary, striated muscle that is found in the walls and histological foundation of the heart, specifically the myocardium. Cardiac muscle is one of three major types of muscle, the others being skeletal and smooth muscle.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 22 - 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 23 - 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 24 - The predominant receptors in the hearts conduction system are? ...

    Incorrect

    • The predominant receptors in the hearts conduction system are?

      Your Answer:

      Correct Answer: Î’1

      Explanation:

      All of the components of the intrinsic conduction system contain autorhythmic cells that spontaneously depolarize. In the absence of extrinsic neural or hormonal influences, the SA node pacing rate would be about 100 beats per minute (bpm). The heart rate and cardiac output, however, must vary in response to the needs of the body’s cells for oxygen and nutrients under varying conditions. In order to respond rapidly to changing requirements of the body’s tissues, the heart rate and contractility are regulated by the autonomic nervous system (ANS), hormones, and other factors. The ANS has two interacting systems: the sympathetic and parasympathetic systems. Sympathetic receptors: There are two types of adrenergic receptors: β and α. In the cardiovascular system there are β1, β2, α1, and α2 adrenergic receptors. β1 adrenergic receptors are expressed in the heart conduction system (in the SA node, AV node, and on atrial and ventricular cardiomyocytes). The activation of β1 receptors increases heart rate (via the SA node), and contractility.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 25 - Concerning S3, which of the following statements is INCORRECT? ...

    Incorrect

    • Concerning S3, which of the following statements is INCORRECT?

      Your Answer:

      Correct Answer: Coincide with atrial contraction

      Explanation:

      A third heart sound also called a ventricular gallop occurs at the beginning of diastole after S2 and is lower in pitch than S1 or S2 as it is not of valvular origin. The third heart sound is benign in youth, some trained athletes, and sometimes in pregnancy but if it re-emerges later in life it may signal cardiac problems, such as a failing left ventricle as in dilated congestive heart failure (CHF). S3 is thought to be caused by the oscillation of blood back and forth between the walls of the ventricles initiated by blood rushing in from the atria. The reason the third heart sound does not occur until the middle third of diastole is probably that during the early part of diastole, the ventricles are not filled sufficiently to create enough tension for reverberation. It may also be a result of tensing of the chordae tendineae during rapid filling and expansion of the ventricle. In other words, an S3 heart sound indicates increased volume of blood within the ventricle. An S3 heart sound is best heard with the bell-side of the stethoscope (used for lower frequency sounds). A left-sided S3 is best heard in the left lateral decubitus position and at the apex of the heart, which is normally located in the 5th left intercostal space at the midclavicular line. A right-sided S3 is best heard at the lower-left sternal border. The way to distinguish between a left and right-sided S3 is to observe whether it increases in intensity with inhalation or exhalation. A right-sided S3 will increase on inhalation, while a left-sided S3 will increase on exhalation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 26 - 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 27 - The following is true of the sinus node: ...

    Incorrect

    • The following is true of the sinus node:

      Your Answer:

      Correct Answer: It generates impulses automatically & at a quicker rate than other cardiac cells

      Explanation:

      The SA node exhibits automaticity. It generates the impulses to which the heart beats. It fires at a faster speed than the rest of the nervous components of the heart i.e. the AV nodes, purkinje fibers. This is the reason when the SA node fails the heart beats to the rhythm of the AV node.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 28 - Sinus bradycardia may be caused by disease of which of the following: ...

    Incorrect

    • Sinus bradycardia may be caused by disease of which of the following:

      Your Answer:

      Correct Answer: Right coronary artery

      Explanation:

      Disease of the right coronary artery may cause sinus bradycardia and AV nodal block.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 29 - 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 indicates the rise in the atrial pressure due to filling of the atria with blood before the tricuspid valve opens during the diastolic phase of contraction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds

  • Question 30 - 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

SESSION STATS - PERFORMANCE PER SPECIALTY

Cardiovascular (1/6) 17%
Medicine (1/6) 17%
Passmed
Retry this test Dashboard