QUESTIONS AND ANSWERS (A+ GUIDE SOLUTION)
Question 1
Which valve is located between the right atrium and the right ventricle?
A) Aortic
B) Mitral
C) Pulmonary
D) Tricuspid
Correct Answer: D) Tricuspid
Rationale: The tricuspid valve is an atrioventricular valve that controls blood flow from the
right atrium into the right ventricle.
Question 2
What is the correct sequence of the heart's electrical conduction pathway?
A) AV node -> SA node -> Bundle of His -> Purkinje fibers
B) SA node -> AV node -> Bundle of His -> Purkinje fibers
C) Bundle of His -> SA node -> AV node -> Purkinje fibers
D) SA node -> Purkinje fibers -> AV node -> Bundle of His
Correct Answer: B) SA node -> AV node -> Bundle of His -> Purkinje fibers
Rationale: The electrical impulse originates in the SA node (the pacemaker), travels to the AV
node, is conducted down the Bundle of His, and is then distributed throughout the ventricles
via the Purkinje fibers.
Question 3
Preload is defined as the:
A) Resistance the ventricle must overcome to eject blood.
B) Volume of blood in the ventricles at the end of diastole.
C) Amount of blood ejected with each heartbeat.
D) Product of heart rate and stroke volume.
Correct Answer: B) Volume of blood in the ventricles at the end of diastole.
,Rationale: Preload is the stretch on the ventricular muscle fibers just before contraction. It is
determined by the volume of blood filling the ventricle during diastole (end-diastolic volume).
Question 4
Afterload is defined as the:
A) Resistance the ventricle must overcome to eject blood.
B) Volume of blood in the ventricles at the end of diastole.
C) Amount of blood ejected with each heartbeat.
D) Product of heart rate and stroke volume.
Correct Answer: A) Resistance the ventricle must overcome to eject blood.
Rationale: Afterload is the pressure or resistance against which the ventricles must pump to
open the semilunar valves (aortic and pulmonic) and eject blood. It is primarily determined by
systemic vascular resistance and blood pressure.
Question 5
A patient presents with a regular, narrow-complex tachycardia at a rate of 180 bpm. P waves are
not discernible. This rhythm is best identified as:
A) Sinus Tachycardia
B) Atrial Fibrillation
C) Supraventricular Tachycardia (SVT)
D) Ventricular Tachycardia
Correct Answer: C) Supraventricular Tachycardia (SVT)
Rationale: SVT is characterized by a regular, narrow QRS (<0.12 sec) rhythm with a rate
typically over 150 bpm where P waves are often hidden or absent. Sinus tachycardia usually
has visible P waves and a more variable rate.
Question 6
What is the first-line treatment for a stable patient with Supraventricular Tachycardia (SVT)?
A) Synchronized cardioversion
B) Vagal maneuvers
C) Amiodarone infusion
,D) Immediate defibrillation
Correct Answer: B) Vagal maneuvers
Rationale: For a stable patient in SVT, the initial intervention should be to attempt vagal
maneuvers (e.g., Valsalva, carotid sinus massage) to stimulate the vagus nerve and slow AV
conduction, which may terminate the rhythm.
Question 7
A stable patient in SVT does not respond to vagal maneuvers. What is the recommended first-
line medication and dose?
A) Adenosine 6 mg rapid IV push
B) Amiodarone 150 mg IV over 10 minutes
C) Diltiazem 0.25 mg/kg IV
D) Metoprolol 5 mg IV push
Correct Answer: A) Adenosine 6 mg rapid IV push
Rationale: Adenosine is the drug of choice for stable, narrow-complex SVT. The initial dose is 6
mg given as a rapid IV push, followed by a saline flush. If unsuccessful, a second dose of 12 mg
may be given.
Question 8
A patient with a regular, wide-complex tachycardia and a palpable pulse becomes unstable
(hypotensive, altered mental status). What is the priority intervention?
A) Administer adenosine 6 mg IVP.
B) Perform synchronized cardioversion.
C) Begin chest compressions.
D) Administer amiodarone 150 mg IV.
Correct Answer: B) Perform synchronized cardioversion.
Rationale: For any unstable tachycardia with a pulse (wide or narrow), immediate
synchronized cardioversion is the treatment of choice to rapidly restore a stable rhythm and
improve perfusion.
, Question 9
A patient presents with unstable bradycardia (HR 40, hypotensive, confused). Atropine is
ineffective. Which of the following is the next appropriate intervention?
A) Administer a fluid bolus.
B) Administer adenosine.
C) Begin transcutaneous pacing or an epinephrine/dopamine infusion.
D) Perform synchronized cardioversion.
Correct Answer: C) Begin transcutaneous pacing or an epinephrine/dopamine infusion.
Rationale: According to the ACLS bradycardia algorithm, if atropine is ineffective, the next
step is to initiate transcutaneous pacing or start a chronotropic infusion like epinephrine (2-10
mcg/min) or dopamine.
Question 10
Which of the following cardiac arrest rhythms are considered "non-shockable"?
A) Ventricular Fibrillation and Ventricular Tachycardia
B) Pulseless Electrical Activity (PEA) and Asystole
C) Supraventricular Tachycardia and Atrial Fibrillation
D) Asystole and Ventricular Fibrillation
Correct Answer: B) Pulseless Electrical Activity (PEA) and Asystole
Rationale: PEA and asystole are non-shockable rhythms because there is no organized or
chaotic electrical activity that can be reset by a shock. Treatment focuses on high-quality CPR,
epinephrine, and identifying/treating reversible causes.
Question 11
In the ACLS algorithm for VF/Pulseless VTach, after the first shock is delivered, what is the
immediate next step?
A) Check for a pulse.
B) Administer 1 mg of epinephrine.
C) Resume CPR for 2 minutes.
D) Analyze the rhythm again.
Correct Answer: C) Resume CPR for 2 minutes.