B4M2Q1 21-22 Flashcards
Which of the following forms the base of the heart?
a. Left atrium
b. Right atrium
c. Right ventricle
d. Left ventricle
a. Left atrium
Lead II vector points to which of the following?
a. -30 degrees
b. +120 degrees
c. +60 degrees
d. +90 degrees
c. +60 degrees
The left coronary artery supplies the:
a. Right bundle branch
b. Sinoatrial node
c. Posterior 1/3 of the ventricular septum
d. Atrioventricular node
a. Right bundle branch
Which of the secondary pacemakers of the heart would have a discharge rate of 40-
60/min?
a. Purkinje fibers
b. Penetrating portions of the AV bundle
c. Atria
d. AV node
d. AV node
Which of the following conveys blood from the right ventricle to the lungs?
a. Aortic arch
b. Ascending aorta
c. Descending aorta
d. Pulmonary trunk
d. Pulmonary trunk
Which of the following chest lead placements is correct?
a. V6 -5th Intercostal space, left mid axillary line at the same horizontal level as V4 and V5
b. V5 - left posterior axillary line at the same horizontal level as V4
c. V1 - 5th intercostal space, right sternal border
d. V4 - 4th Intercostal space, left midclavicular line
a. V6 -5th Intercostal space, left mid axillary line at the same horizontal level as V4 and V5
The right coronary artery supplies the:
a. Right atrium
b. Right bundle branch
c. Anterior 2/3 of the ventricular septum
d. Most of the left atrium
a. Right atrium
Which of the following shows the correct pairing of clinical valve area to the area
where the heart sound is heard best?
a. Aortic area: upward along the aorta
b. Pulmonic area: over the left ventricle
c. Mitral area: over the right ventricle
d. Tricuspid area: upward along the pulmonary areas
a. Aortic area: upward along the aorta
Which of the following is derived from the right anterior cardinal vein and right
common cardinal vein?
a. Inferior vena cava
b. Superior vena cava
c. Aortic arch
d. Internal jugular vein
b. Superior vena cava
How does the ductus venosus form a bypass through the liver?
a. It shifts blood from the left to right side of the body.
b. It carries all blood from the placenta to the embryo.
c. It shunts blood from the left to the right anterior cardinal vein.
d. It enables most blood from placenta to pass directly to the heart without passing the liver.
d. It enables most blood from placenta to pass directly to the heart without passing the liver.
Which of the phases of the myocardial action potential shown below is characterized
primarily calcium entry via voltage-regulated, L-type calcium channels?
a. Phase 0
b. Phase 1
c. Phase 2
d. Phase 4
c. Phase 2
A person’s electrocardiogram (ECG) has no P wave, but has a normal QRS complex
and a normal T wave. Therefore, his pacemaker is located in the:
a. Bundle of His
b. Sinoatrial (SA) node
c. Purkinje system
d. Atrioventricular (AV) node
d. Atrioventricular (AV) node
Which of the phases of the myocardial action potential shown below corresponds to
rapid sodium entry through voltage-gated, fast sodium channels?
a. Phase 4
b. Phase 1
c. Phase 0
d. Phase 3
c. Phase 0
Which of the following components of an ECG represents ventricular depolarization?
a. PR interval
b. QRS complex
c. T wave
d. P wave
b. QRS complex
Which of the following structures is found in the right atrium?
a. Papillary muscles
b. Trabeculae carnae
c. Sinus venosus
d. Chordae tendinae
c. Sinus venosus
A 50-year-old man came in to the ER complaining of severe, crushing chest pain
noted about 30 minutes prior to consult. An ECG was immediately taken which
showed ST segment elevations at contiguous leads. Which myocardial wall is
involved?
a. Anterior wall
b. Anteroseptal wall
c. Inferior wall
d. High lateral wall
c. Inferior wall
Minnie is learning about the ECG. She knows that the PR interval is increased if
conduction velocity through the AV node is slowed. Where is the AV node located?
a. Junction of the crista terminalis in the upper wall of the right atrium and the
opening of the superior vena cava
b. Inferior wall of the right atrium adjacent to the opening of the coronary sinus
c. Posterior wall of the right atrium immediately behind the tricuspid valve and
adjacent to the opening of the coronary sinus
d. Arises from the compact node and penetrates the central fibrous body of
the heart
c. Posterior wall of the right atrium immediately behind the tricuspid valve and
adjacent to the opening of the coronary sinus
Which of the following contains the lubricant that facilitates movements of the heart?
a. Pericardial cavity
b. Oblique pericardial sinus
c. Transverse pericardial sinus
d. Pericardium
a. Pericardial cavity
Which of the following opens between the inferior vena cava and the atrio-ventricular
openings and is guarded by the Thebesian valve?
a. Right Atrio-Ventricular Opening
b. Sinus Venosus
c. Coronary Sinus
d. Superior Vena Cava
c. Coronary Sinus
Which of the following separates the left and the right ventricles?
a. Atrial septum
b. Atrioventricular septum
c. Infundibular septum
d. Interventricular septum
d. Interventricular septum
In the sinoatrial (SA) node, phase 4 depolarization (pacemaker potential) is
attributable to which of the following?
a. An increase in K+ conductance
b. A decrease in Ca2+ conductance
c. An increase in Na+ conductance
d. A decrease in Cl- conductance
c. An increase in Na+ conductance
Which of the following is correct about Einthoven’s law?
a. Electrical potentials of any two of the three bipolar limb leads are known at
any given instant, the third one can be determined mathematically by
subtracting the first two limb leads.
b. Electrical potentials of any two of the three bipolar limb leads are known at
any given instant, the third one can be determined mathematically by
summing the first two limb leads.
c. Electrical potentials of any two of the three bipolar limb leads are known by
summing up the three limb leads.
d. An imaginary triangle with the heart at its center, can be approximated by
placing electrodes on both arms and both legs.
b. Electrical potentials of any two of the three bipolar limb leads are known at
any given instant, the third one can be determined mathematically by
summing the first two limb leads.
Which part of the cardiac conduction system generates the portion of the ECG
pointed by the arrow?
a. Right bundle branch
b. Purkinje fibers
c. AV node
d. Sinus node
c. AV node
Trisha, a level 1 student, was given an example of a 12-Lead ECG. Knowing the
components of a normal electrocardiogram, she noted that in the ECG she was
reading had no P wave. What happened to this patient’s heart?
a. There was an increased amplitude
b. The atrial muscle repolarized
c. There was no ventricular depolarization
d. The atrial muscle did not depolarize
d. The atrial muscle did not depolarize
Activation of the postganglionic parasympathetic nerves results in:
a. Constriction of coronary arteries
b. Cardiac acceleration
c. Increased force of cardiac contraction
d. Dilatation of cardiac chambers
a. Constriction of coronary arteries
Which of the following components of an ECG represents ventricular repolarization?
a. QT segment
b. QRS complex
c. T wave
d. P wave
c. T wave
A 45-year-old male patient, diabetic, with chronic kidney disease (CKD) came in to
the ER complaining of body malaise, anorexia and vomiting. The following ECG was
taken. Identify the axis.
a. Left axis deviation
b. Extreme right axis deviation
c. Right axis deviation
d. Normal axis
c. Right axis deviation
The vector of the waveform pointed in ECG points to what direction?
a. Towards the area of ventricular contraction
b. Towards the positive electrode of the lead
c. Towards both the positive and negative electrodes of the lead
d. Towards the negative electrode of the lead
b. Towards the positive electrode of the lead
Which of the following components of an ECG represents atrial depolarization?
a. QRS complex
b. PR interval
c. P wave
d. T wave
c. P wave
The waveform pointed by the arrow in figure represents which of the following?
a. QRS complex
b. R wave
c. P wave
d. T wave
b. R wave
Which of the following Phases of the ventricular action potential is the Resting
membrane potential?
a. Phase 2
b. Phase 4
c. Phase 1
d. Phase 3
b. Phase 4
TRUE regarding the right auricle:
a. it’s a remnant of the foramen ovale
b. it’s conical in shape
c. it contains the trabeculae carnae
d. it contains fibrous chords extending from the apices of the papillary muscles
to the cusps of the tricuspid valve
b. it’s conical in shape
Which of the following components of an ECG represents AV nodal conduction time?
a. QRS complex
b. PR interval
c. T wave
d. P wave
b. PR interval
Which of the following demonstrates the slowest action potential conduction velocity?
a. AV node
b. Purkinje fibers
c. Ventricular muscle
d. SA node
a. AV node
What part of the aorta lies at T-T12?
a. Descending aorta
b. Ascending aorta
c. Aortic arch
d. Abdominal aorta
a. Descending aorta
In the sinoatrial (SA) node, phase 0 is attributable to which of the following?
a. An increase in Na+ conductance
b. An increase in Ca2+ conductance
c. An increase in K+ conductance
d. A decrease in Cl- conductance
b. An increase in Ca2+ conductance
What is the waveform pointed by the arrow in the figure represent?
a. QRS complex
b. T wave
c. Q wave
d. P wave
b. T wave
Identify the ventricular rate of this ECG:
a. 50 bpm
b. 60 bpm
c. 75 bpm
d. 100 bpm
c. 75 bpm
Which of the following statements is TRUE of the cardiac skeleton?
a. The septum membranaceum is made of elastic fibers found around
atrioventricular openings.
b. The trigona fibrosi consists of triangular fibrous tissue between the right and
left atria.
c. The annulus fibrosi is found in the superior portion of the interventricular
septum.
d. It is made of osteoid tissue that serves as a central support of the heart.
b. The trigona fibrosi consists of triangular fibrous tissue between the right and
left atria.
Which of the following comes from the anastomotic shunt?
a. Posterior cardinal vein
b. Left brachiocephalic vein
c. Right brachiocephalic vein
d. Anterior cardinal vein
b. Left brachiocephalic vein
Mishka, a level 1 student, was presented this ECG. She was tasked to determine the
heart rate of the ECG. What is the heart rate of the ECG presented below?
a. 100
b. 300
c. 75
d. 150
a. 100
Which of the following conducting systems has the highest conducting velocity?
a. SA node
b. Atrial muscle
c. Purkinje fibers
d. AV node
c. Purkinje fibers
From which pair of aortic arches is the arch of the aorta derived from?
a. 1st
b. 3rd
c. 4th
d. 2nd
c. 4th
Which of the following methods for determining the heart rate in ECG is the least
accurate?
a. P-R method
b. R-R method
c. 6 second method
d. 1500 method
c. 6 second method
Which phase of the myocardial action potential shown below would be characterized
by increased potassium permeability and potassium efflux through delayed rectifier
potassium channels?
a. Phase 3
b. Phase 0
c. Phase 2
d. Phase 1
a. Phase 3
Which of the phases of the myocardial action potential shown below is associated
with the transient outward potassium current?
a. Phase 4
b. Phase 1
c. Phase 2
d. Phase 3
b. Phase 1
The His bundle electrogram (HBE) records the electrical activity in the AV node,
bundle of His, and the Purkinje system by inserting a catheter containing an electrode
positioning it close to the tricuspid valve. With the HBE and the standard
electrocardiographic leads, it is possible to accurately time 3 intervals. Which of the
following intervals represents the AV nodal conduction time, with a normal value of
92ms?
a. HV interval
b. AH interval
c. PA interval
d. PR interval
b. AH interval
PA AH HV 27 92 43
Which of the following return/s poorly oxygenated blood from the body of the embryo?
a. Right umbilical vein
b. Common cardinal veins
c. Vitelline veins
d. Left umbilical vein
b. Common cardinal veins
Which of the following tributaries of the coronary sinus is also called Thebesius’
veins?
a. Venae cordis minimae
b. Great cardiac vein
c. Posterior vein of the left atrium
d. Small cardiac vein
a. Venae cordis minimae
Which of the following structure connects directly with surrounding atrial muscle
fibers?
a. AV node
b. SA node
c. Purkinje fibers
d. Internodal pathways
d. Internodal pathways
