MT #1 Cardiovascular + Physiology of the Heart Flashcards
What determines the contractility?
a. isotonic tension
b. isometric tension
c. maximum isometric tension, maximum contraction speed
d. contraction speed
c. maximum isometric tension, maximum contraction speed
What influences the efficiency of the working fibers in the heart?
a. parasympathetic stimulation
b. sympathetic inhibition
c. direct electrical stimulation
d. sympathetic stimulation
d. sympathetic stimulation
How does the cardiac output change during the direct stimulation of the heart?
a. the C.O. doesn`t change
b. the C.O. decreases slightly
c. the C.O. increases significantly
d. the C.O. decreases significantly
a. the C.O. doesn`t change
How does the cardiac output change if we stimulate the heart through its sympathetic nerve?
a. the C.O. decreases continously
b. the C.O. increases continously
c. the C.O. doesn`t change
d. the C.O. increases slightly
b. the C.O. increases continously
How does the systole/diastole rate change with direct stimulation of the heart?
a. systole and diastole decrease
b. systole increases, dyastole decreases
c. systole doesn`t change, dyastole decreases
d. systole decreases, dyastole increases
c. systole doesn`t change, dyastole decreases
How does the systole/diastole ratio change if we stimulate the heart through its sympathetic nerve?
a. it increases
b. it decreases
c. it increases the muscle force only
d. the ratio doesn`t change too much
d. the ratio doesn`t change too much
How can we measure the cardiac output?
a. on the basis of the Ficks-principle
b. on the basis of the Van`t Hoff law
c. on the basis of the Laplace law
d. on the basis of Henderson-Hasselbalch equation
a. on the basis of the Ficks-principle
What formula can be used to calculate the cardiac output?
a. C.O.=QtO2x(CaO2-CvO2)
b. C.O.=QtO2/(CaO2-CvO2)
c. C.O.=QtO2/(CvO2-CaO2)
d. C.O.=QtO2/(CaO2xCvO2)
b. C.O.=QtO2/(CaO2-CvO2)
Can we apply the Stewart-principle for the determination of the cardiac output?
a. yes, because we measure the volume
b. yes, when we inject tritiated water
c. yes, but modified, instead of volume we measure volume flow
d. no
c. yes, but modified, instead of volume we measure volume flow
What efficiency does the heart have?
a. 80%
b. 30-40%
c. 4%
d. 10-20%
d. 10-20%
What is the external work of the heart?
a. The product of systolic volume and the mean arterial pressure
b. The quotient of pulse pressure and the circulatory mid-pressure
c. The product of cardiac output and the arterial mid-pressure
d. the difference of the pressure-work and the kinetic-work
a. The product of systolic volume and the mean arterial pressure
What can we show with the help of the Rushmer-diagram?
a. the ratio of external and internal work
b. the ratio of the active and passive component of the external work of the heart
c. the difference between the external and internal work of the heart
d. the efficiency of the work of the heart
b. the ratio of the active and passive component of the external work of the heart
What does the passive work of the heart derive from?
a. from the tension during the isovolumetric contraction
b. from the isovolumetric relaxation
c. from the energy stored in the elastic components
d. from the tension of the aortic wall
c. from the energy stored in the elastic components
How do the pressure and volume of the left ventricle change during the fast ejection phase of systole?
a. the pressure does not change, the volume decreases significantly
b. the pressure drops, the volume decreases
c. the pressure increases, the volume does not change
d. the pressure increases, the volume decreases
d. the pressure increases, the volume decreases
How does the efficiency of the heart change with increasing ventricular volume?
a. It decreases
b. It increases
c. It does not change
d. It decreases, since the oxygen consumption is less
a. It decreases
What happens when we stimulate the heart muscle to the threshold potential?
a. Cl and Ca influx
b. K outflow, Na inflow
c. Na influx
d. Ca and Na influx
c. Na influx
What happens at a potential of +25 mV?
a. Na inflow stops, K inflow, Cl outflow
b. Ca inflow, Na outflow
c. Na inflow continues, K outflow stops
d. Na inflow stops; Cl inflow begins
d. Na inflow stops; Cl inflow begins
What influx happens during the plateau-phase of the heart muscle’s AP?
a. slow Ca inflow, slow K outflow
b. quick Ca inflow, slow K outflow
c. slow Ca outflow, quick K inflow
d. quick Na inflow, slow Ca inflow
a. slow Ca inflow, slow K outflow
What is going on in the phase leading to the total repolarization of the heart muscle?
a. slow Ca inflow, slow K outflow
b. rapid K outflow, Ca inflow stops
c. Ca inflow, slow K outflow
d. Na inflow, slow Ca inflow
b. rapid K outflow, Ca inflow stops
How does the potassium conductance change during phase 3 of the AP of the working fibers of the heart?
a. it decreases
b. it does not change
c. it increases
d. its change is parallel to the sodium conductance
c. it increases
Which ion flux causes the plateau phase in the AP of the heart muscle?
a. potassium
b. chloride
c. sodium
d. mainly calcium
d. mainly calcium
How does the sodium conductance change in phase 1 of the AP of the working fibers of the heart?
a. it ceases suddenly
b. it increases
c. it decreases continously
d. it does not change
a. it ceases suddenly
What is the most important difference between the action potential of the heart muscle and that of the skeletal muscle?
a. the AP of the heart muscle is shorter
b. the AP of the skeletal muscle has no plateau phase
c. the contraction of the heart muscle starts after the AP
d. the AP of the skeletal muscle overlaps its mechanogram
b. the AP of the skeletal muscle has no plateau phase
What answer is produced when the stimulus is given during the absolute refractory phase?
a. a new AP is generated
b. a new AP is produced when the stimulus is strong enough
c. no AP can be produced
d. AP is generated about 300 msecs later
c. no AP can be produced
Which statement is correct for the relative refractory period?
a. a slight stimulus may elicit a new AP
b. no stimulus can elicit an AP
c. a normal stimulus causes an AP
d. only a very strong stimulus can elicit an AP
d. only a very strong stimulus can elicit an AP
Which statement is correct for the supernormal phase?
a. a very slight stimulus can provoke an AP
b. only a strong stimulus elicits an AP
c. AP cannot be elicited at all in this phase
d. only serial stimuli elicit a new AP
a. a very slight stimulus can provoke an AP
In which phase of the AP can a stimulus cause life threatening ventricular fibrillation?
a. absolute refractory period
b. supernormal phase
c. relative refractory period
d. immediately after the diastole
b. supernormal phase
What is the center of the nomotopic stimulus formation?
a. septum
b. Purkinje fibers
c. sinoatrial node
d. bundle of His
c. sinoatrial node
Which formation generates the pacemaker activity in the heart?
a. large round cells of the SA node
b. elongated cells of the sinoauricular node
c. sympathetic fibers
d. parasympathetic fibers
a. large round cells of the SA node
Which formation synchronizes and delays the pacemaker signal?
a. large round cells of the SA node
b. elongated cells of the SA node
c. pacemaker cells of the SA node
d. working muscle fibers
b. elongated cells of the SA node
The depolarisation of the pacemaker cells begins at what potential?
a. -90 mV
b. -35 mV
c. -55 mV
d. +35 mV
c. -55 mV
What kind of ion channels function in the period of spontaneous diastolic depolarisation?
a. Ih channels, slow Na-channels
b. slow Na-channels
c. fast Na-channels
d. Ih channels, T and L-type channels
d. Ih channels, T and L-type channels
Which channels determine the 0 phase of the action potential of the pacemaker cells?
a. fast Na-channels
b. slow Na-channels
c. Ih channels
d. T and L-type Ca-channels
a. fast Na-channels
What are the characteristics of the subendocardial conduction?
a. the specialized fibre system projects deep into the ventricular muscle
b. The specialized fibre system does not project deep into the ventricular muscle
c. it occures in large animals
d. elongates the heart cycle
b. The specialized fibre system does not project deep into the ventricular muscle
What are the characteristics of the epicardial conduction?
a. it occures in small animals
b. the specialized fibre system is on the surface of the ventricle
c. the specialized fibre system projects deep into the muscles of the ventricle
d. elongates the heart cycle
c. the specialized fibre system projects deep into the muscles of the ventricle
What is the function of the sinoatrial node?
a. ventricular activation
b. synchronizes atrial and ventricular contraction
c. delays the conduction time
d. nomotopic excitation
d. nomotopic excitation
What is the function of the atrioventricular node?
a. delays the excitation
b. synchronizing the contraction of the two ventricles
c. nomotopic excitation
d. fast ventricular activation
a. delays the excitation
What is the function of the annulus fibrosus?
a. ventricular activation
b. synchronization
c. nomotopic stimulus generation
d. heterotopic stimulus generation
b. synchronization
What is the function of the His-bundle?
a. delays the conduction of the stimulus
b. nomotopic stimulus generation
c. fast ventricular activation
d. synchronization atrial and ventricular activity
c. fast ventricular activation
Where is the conduction the slowest in the heart?
a. in the ventricle
b. in the His-bundle and the Tawara-stalk
c. in the SA node
d. in the AV node
d. in the AV node
Where is the conductance the fastest in the heart?
a. in the His and Tawara bundles
b. in the working muscle fibres
c. in the ventricles
d. in the atriovenrticular node
a. in the His and Tawara bundles
How does sympathetic stimulation affect the frequency of the heart?
a. it decreases the frequency
b. it increases the frequency
c. there is no change
d. first it increases, later it decreases
b. it increases the frequency
How does parasympathetic stimulation affect the frequency of the heart?
a. it increases the frequency
b. there is no change
c. it decreases the frequency
d. first it increases, later it decreases
c. it decreases the frequency
What mediates the sympathic effect in the heart?
a. cAMP concentration decreases
b. inhibiting of the beta-1 receptor
c. stimulating the nicotinic acetylcholine receptor
d. stimulating the beta-1 receptor
d. stimulating the beta-1 receptor
How does the AP of the heart change during sympathetic stimulation?
a. the steepness of the SDD increases
b. the MDP lowers
c. the steepness of the SDD decreases
d. the MDP does not change
a. the steepness of the SDD increases
How does the parasympathetic effect act in the heart?
a. via beta-1 receptor stimulation
b. via acetylcholine receptor stimulation
c. by inhibiting the beta-1 receptors
d. increasing the cAMP concentration
b. via acetylcholine receptor stimulation
What nerval effect determines the heart function at rest?
a. sympathetic inhibition
b. sympathetic stimulation
c. parasympathetic stimulation
d. parasympathetic inhibition
d. parasympathetic inhibition
What neural effects act on the heart in case of increased physical activity?
a. increased sympathetic stimulation, reduced parasympathetic activity
b. increased parasympathetic activity
c. reduced sympathetic activity
d. increased vagal stimulation
a. increased sympathetic stimulation, reduced parasympathetic activity
What is the bathmotrop effect?
a. an effect influencing frequency
b. an effect influencing threshold
c. an effect influencing force generation
d. an effect influencing contractility
b. an effect influencing threshold
What is the dromotrop effect?
a. an effect influencing frequency
b. an effect influencing threshold
c. an effect influencing conductance
d. an effect influencing SDD
c. an effect influencing conductance
What is the inotrop effect?
a. an effect influencing frequency
b. an effect influencing threshold
c. an effect influencing force generation
d. an effect influencing SDD
c. an effect influencing force generation
What is the chronotrop effect?
a. an effect influencing frequency
b. an effect influencing force generation
c. an effect influencing conductance
d. an effect influencing threshold
a. an effect influencing frequency
How does the parasympathetic nervous system alter the activity of the heart?
a. negative inotrop, chronotrop, positive dromotrop, bathmotrop effect
b. negative inotrop, chronotrop, dromotrop, bathmotrop effect
c. positive inotrop, chronotrop, dromotrop, bathmotrop effect
d. positive inotrop, chronotrop, negative dromotrop, bathmotrop effect
b. negative inotrop, chronotrop, dromotrop, bathmotrop effect
How does sympathetic nervous system alter the activity of the heart?
a. negative inotrop, chronotrop, positive dromotrop, bathmotrop effect.
b. negative inotrop, chronotrop, dromotrop, bathmotrop effect
c. positive inotrop, chronotrop, dromotrop, bathmotrop effect
d. positive inotrop, chronotrop, negative dromotrop, bathmotrop effect
c. positive inotrop, chronotrop, dromotrop, bathmotrop effect
What is characteristic of the electro-mechanical coupling in the heart muscle?
a. its main element is the voltage sensitive channel on the membrane of the SR
b. the process is started by the opening of the Na-dependent Ca channel
c. its basis is the increase of the IC potassium level
d. the stimulation of the DHP sensitive proteins
d. the stimulation of the DHP sensitive proteins
What directly starts the cross bridge cycling in the heart muscle?
a. the calcium signal
b. conformation change of the voltage c. dependent DHP receptor and T-tubulus
opening of DHP-type Ca channels on the SP membrane
d. pumping of the calcium into the SR
a. the calcium signal
What mechanisms make calcium flow out of the IC?
a. ATP dependent calcium pump towards the EC, Na/Ca antiporter towards SR
b. ATP dependent calcium pump towards the SR, Na/Ca antiporter towards EC
c. Na/Ca antiporter towards EC and SR
d. ATP dependent Ca pump towards the SR and EC
b. ATP dependent calcium pump towards the SR, Na/Ca antiporter towards EC
Which of the following statements is false?
a. regarding its function, the heart can be considered as an electric dipole
b. a dipole can be described by a vector
c. depolarization vector points from the positive to the negative direction
d. an electrical signal has direction, measure and polarity
c. depolarization vector points from the positive to the negative direction
Who constructed the first ECG equipment?
a. A. L. Lavoisier.
b. G. R. Kirchhoff.
c. C. Bernard.
d. W. Einthoven.
d. W. Einthoven.
Which of the following statements is true?
a. the sum of the voltage differences measured between the vertices of the equilateral triangle around the dipole is always zero.
b. the sum of voltage differences measured between the vertices of the triangle around the dipole equals unity
c. the Einthoven’s lead is a unipolar lead
d. the depolarization wave causes an upward defelction on the ECG
a. the sum of the voltage differences measured between the vertices of the equilateral triangle around the dipole is always zero.
What is the principle of the bipolar lead?
a. potential difference between two electrodes is compared to a third reference point
b. potential difference between two electrodes placed on the surface of a dipol is measured
c. potential difference between two electrodes is compared to a third neutral point
d. potential difference between two electrodes is compared to standard voltage value
b. potential difference between two electrodes placed on the surface of a dipol is measured
What can be seen in the oscilloscope during full depolarization?
a. an upwards deflection
b. a downwards deflection
c. an isoelecric line - no deflection
d. an irregular line
c. an isoelecric line - no deflection
What is the Einthoven’s first lead?
a. reference electrode on right arm, measuring electrode on left leg
b. reference electrode on left arm, measuring electrode on left leg
c. reference electrode on right arm, measuring electrode on right leg
d. reference electrode on right arm, measuring electrode on left arm
d. reference electrode on right arm, measuring electrode on left arm
What is the Einthoven’s second lead?
a. reference electrode on right arm, measuring electrode on left leg
b. reference electrode on left arm, measuring electrode on left leg
c. reference electrode on right arm, measuring electrode on right leg
d. reference electrode on right arm, measuring electrode on left arm
a. reference electrode on right arm, measuring electrode on left leg
What is the Einthoven’s third lead?
a. reference electrode on right arm, measuring electrode on left leg
b. reference electrode on left arm, measuring electrode on left leg
c. reference electrode on right arm, measuring electrode on right leg
d. reference electrode on right arm, measuring electrode on left arm
b. reference electrode on left arm, measuring electrode on left leg
Why is the integral vector of the heart not zero?
a. the measurment points do not form an exact triangle
b. the stimulus passing between the atrium and the ventricle is slowing down
c. the heart is assymmetric it has altering width of wall and the SA node is not in the middle
d. speed of conduction is different in all directions
c. the heart is assymmetric it has altering width of wall and the SA node is not in the middle
With which state of the atrial activity does the ventricular depolarization coincide?
a. depolarization
b. activated state
c. repose state
d. repolarization
d. repolarization
What does the T-wave describe on the ECG?
a. atrial depolarization
b. SA node depolarization
c. ventricular repolarization
d. atrial repolarization
c. ventricular repolarization
What does the PQ segment describe on the ECG?
a. SA node depolarization
b. atrio-ventricular conduction
c. ventricular depolarization
d. atrial repolarization
b. atrio-ventricular conduction
What does the QRS complex describe on the ECG?
a. full atrial depolarization
b. full repolarization
c. ventricular depolarization, atrial repolarization
d. ventricular repolarization, atrial depolarization
c. ventricular depolarization, atrial repolarization
What makes the Q wave point downwards?
a. ventricular depolarization spreads to the vertex of the heart
b. repolarization of the right ventricle
c. atrial repolarization
d. ventricular depolarization spreads toward the base of the heart
d. ventricular depolarization spreads toward the base of the heart
What does the S-T segment describe?
a. full ventricular depolarization
b. ventricle is fully repolarized
c. atrium is depolarized, ventricle is repolarized
d. full repolarization of the atria
a. full ventricular depolarization
What does the T wave represent?
a. atrial repolarization
b. ventricular repolarization
c. atrial depolarization
d. ventricular depolarization
b. ventricular repolarization
What does the T-P segment represent?
a. complete atrial depolarization
b. the beginning of ventricular repolarization
c. complete repolarization, state of rest
d. complete ventricular depolarization
c. complete repolarization, state of rest
What is the essence of the unipolar lead?
a. to measure the voltage fluctuation between a point of the chest and a limb
b. to connect electrodes placed on the chest, and registers the integrated voltage fluctuations
c. to measure the voltage of a single conduction point only
d. to measure the voltage fluctuation between the examining electrode and a place of 0 potential
d. to measure the voltage fluctuation between the examining electrode and a place of 0 potential
Which type of ECG gives precise information about the heart’s anatomical position?
a. vector cardiography
b. esophageal ECG
c. His-Bundle ECG
d. unipolar ECG
a. vector cardiography
What causes heartsound I?
a. Closure of semilunar valves
b. Closure of cuspidal valves
c. Sound of sudden ventricular filling
d. Turbulent flow following atrial systole
b. Closure of cuspidal valves
What causes heartsound II?
a. Closure of cuspidal valves
b. Sound of sudden ventricular filling
c. Closure of semilunar valves
d. Turbulent flow following atrial systole
c. Closure of semilunar valves
Which wave cannot be registered on v. jugularis during the heart-cycle?
a. Wave V
b. Wave C
c. Wave A
d. Wave P
d. Wave P
How long is a complete heart-cycle in dogs?
a. 800 msec
b. 270 msec
c. 530 msec
d. 220 msec
a. 800 msec
What percent of the ventricular volume gets to the periphery during the fast ejection phase of ventricular systole?
a. 60%
b. 80%
c. 90%
d. 50%
b. 80%
Of the following elements of the heart-cycle which is the longest in time?
a. isovolumetric relaxation
b. isovolumetric relaxation
c. ventricular systole
d. atrial systole
c. ventricular systole
Which is the shortest element of the heart-cycle?
a. isovolumetric relaxation
b. atrial systole
c. fast phase of auxotonic contraction
d. isovolumetric contraction
d. isovolumetric contraction
Where is there no valve in the blood flow?
a. v.cava - right atrium
b. right atrium - right ventricle
c. left atrium - left ventricle
d. left atrium - aorta
a. v.cava - right atrium
Where you could find tricuspid valves in the heart?
a. left atrium - left ventricle
b. right atrium - right ventricle
c. left ventricle - aorta
d. right ventricle - a. pulmonalis
b. right atrium - right ventricle
Where you could find bicuspid valves in the heart?
a. right atrium - right ventricle
b. left ventricle - aorta
c. left atrium - left ventricle
d. right ventricle - a. pulmonalis
c. left atrium - left ventricle
What vessel carries venous blood?
a. a. radialis
b. a. carotis communis
c. v. pulmonalis
d. a. pulmonalis
d. a. pulmonalis
What vessel carries arterial blood?
a. v. pulmonalis
b. a. pulmonalis
c. v. cava cranialis
d. v. portae
a. v. pulmonalis
How is the mechanical performance of the heart controlled by the nervous system tone?
a. parasympathethic increases
b. sympathethic increases
c. sympathethic decreases
d. no effect on the mechanical performance
b. sympathethic increases
How does the nervous system influence the heart basal activity?
a. sympathethic predominance
b. parasympathethic inhibition
c. parasympathethic dominance
d. no effect on the basal activity
c. parasympathethic dominance
What is typical for the serial elastic component?
a. inhibits overextension of muscle
b. it is linked parallel with the contractile elements
c. it is stretched in diastole
d. it is relaxed in diastole and stretched in systole
d. it is relaxed in diastole and stretched in systole
What is typical for the parallel elastic component?
a. energy is stored in it due to the tension which is created by the blood flow-in
b. it is relaxed in diastole and stretched in systole
c. it is linked serial to the contractile elements
d. inhibits over extension of muscle
a. energy is stored in it due to the tension which is created by the blood flow-in
What is typical for the collagen-fiber system?
a. it is linked serial to the contractile elements
b. inhibits over extension of muscle
c. it is stretched in diastole and relaxed in systole
d. it has a fiber-mass value = 1
b. inhibits over extension of muscle
What is typical for the isometric phase of the heart activity?
a. movement at the same tension
b. SEC and PEC elements are tensed during this phase
c. there is tension but no movement
d. contractile elements are not contracting but are tensing
c. there is tension but no movement
What is typical for the isotonic phase of the heart activity?
a. sudden tension of the collagen fibers
b. no change in contraction of the contracting components during this phase
c. there is tension but no movement
d. there is movement but no change in tension
d. there is movement but no change in tension
What happens at the maximal loading of the heart?
a. collagen fibers extend and display maximal resistance
b. collagen fibers relax and reduce their resistance to minimal
c. tension of contractile elements increase
d. SEC and PEC components contract maximal
a. collagen fibers extend and display maximal resistance
What conditions allow isotonic contraction?
a. muscle can not move the load
b. muscle can freely move the load
c. muscle works against a spring
d. muscle is supported to a certain length
b. muscle can freely move the load
What condition is needed for isometric contraction?
a. muscle can freely move the load
b. muscle works against a spring
c. muscle can not move the load
d. muscle is supported to a certain length
c. muscle can not move the load
What condition is needed for auxotonic contraction?
a. muscle is supported to a certain length
b. muscle can not move the load
c. muscle can freely move the load
d. muscle works against a spring
d. muscle works against a spring
What type of muscle contraction can be demonstrated in the preload experiment?
a. two-components: first isometric, then isotonic
b. two-components: first isotonic, then isometric
c. one-component: isometric
d. one-component: isotonic
a. two-components: first isometric, then isotonic
What do we demonstrate in the “afterload” experiment?
a. two different type of contractions: first isometric, then isotonic
b. two different type of contractions: first isotonic, then isometric
c. the isometric contraction
d. the isotonic contraction
b. two different type of contractions: first isotonic, then isometric