FISDAP CARDIOLOGY ACTUAL FINALS ANSWERS
AND QUESTIONS SET A+
✔✔Cardioversion involves delivering a shock that is synchronized to occur during the: -
✔✔R wave.
Cardioversion involves delivering a shock that is synchronized to occur during the R
wave, which is when the heart is absolutely refractory. This prevents the shock from
occurring during the relative refractory period (the downslope of the T wave).
Depolarization that occurs during the relative refractory period may induce a non-
perfusing ventricular dysrhythmia, such as pulseless V-Tach or V-Fib. Synchronized
cardioversion is indicated for patients with supraventricular or ventricular tachycardia
who have a pulse, but are hemodynamically unstable.
✔✔Which of the following electrolytes moves slowly into the cardiac cell and maintains
the depolarized state of the cell membrane? - ✔✔Calcium.
The process of depolarization begins as sodium ions rush into the cell. At the same
time, calcium ions enter the cell—albeit more slowly and through specialized
channels—to help maintain the depolarized state of the cell membrane and to supply
calcium ions for contraction of cardiac muscle tissue. During repolarization, the sodium
and calcium channels close, thus stopping the rapid influx of these ions. Then, special
potassium channels open, allowing potassium ions to rapidly exit the cell. This helps
restore the inside of the cell to its negative charge; the proper electrolyte distribution is
then reestablished by pumping sodium ions out of the cell and potassium ions back in.
After the potassium channels close, the sodium-potassium pump helps move sodium
and potassium ions back to their respective locations. For every three sodium ions the
pump moves out of the cell, it moves two potassium ions into the cell, thereby
maintaining the polarity of the cell membrane
✔✔Which of the following cardiac rhythms is associated with bradycardia, and is
characterized by regular R-R intervals and a greater ratio of P waves to QRS
complexes? - ✔✔3rd degree AV block.
,Third-degree AV block is caused by a complete block at the AV node. The SA node
initiates impulses as usual; however, when they reach the AV node, they are blocked.
Resultantly, the ventricles receive no electrical stimulus from the atria, so they initiate
their own impulses, although at a much slower rate. On the ECG, this manifests as a
bradycardic rhythm with more P waves than QRS complexes. The P-P intervals are
regular (some P waves may not be visible because they are buried in a QRS complex),
as are the R-R intervals; however, no relationship exists between a given P wave and
QRS complex. Second-degree AV block type I (Wenkebach) is caused by a progressive
delay at the AV node until an impulse is blocked from entering the ventricles. On the
ECG, this manifests as a progressively lengthening P-R interval until a P wave is
blocked (not followed by a QRS complex). At this point, the R-R interval becomes
irregular, and the presence of this lone P wave increases the ratio of P waves to QRS
complexes. Second-degree AV block type I may or may not be associated with
bradycardia. Second-degree AV block type II is caused by an intermittent block at the
AV node; it occurs when atrial impulses are not conducted to the ventricles. Unlike a
second-degree AV block type I, however, a type II block is characterized by consistent
P-R intervals of the P waves that are conducted. First-degree AV block is an abnormal
delay at the AV node; on the ECG, this manifests with PR intervals greater than 0.20
seconds (120 ms) in duration. In first-degree AV block, all of the atrial impulses are
conducted through the AV node and into the ventricles.
✔✔A 59-year-old male with a monomorphic wide-complex tachycardia at a rate of
220/min, a blood pressure of 80/50 mm Hg, and a decreased level of consciousness,
should be treated with: - ✔✔Synchronized cardioversion.
The patient in this scenario is likely in ventricular tachycardia (V-Tach). Approximately
90% of wide-complex tachycardias are ventricular in origin. Furthermore, he is
hypotensive and has a decreased level of consciousness—signs of hemodynamic
compromise. To prevent his condition from deteriorating further, immediate
synchronized cardioversion, starting with 100 joules, is indicated. Monophasic (or
biphasic equivalent) defibrillation is indicated for patients with pulseless V-Tach and
ventricular fibrillation (V-Fib). Amiodarone (150 mg over 10 minutes) is indicated for
patients with V-Tach who have a pulse, but are hemodynamically stable; it may also be
used as an adjunct for patients with unstable V-Tach when cardioversion alone is not
effective. Magnesium sulfate (1 to 2 g) is indicated for patients with torsade de
pointes—a variant of polymorphic V-Tach.
✔✔ECG indicators of Wolff-Parkinson-White (WPW) syndrome include: - ✔✔Short PR
intervals, delta waves, and QRS widening.
Wolff-Parkinson-White (WPW) syndrome is a condition in which accessory pathways—
called the bundle of Kent—bypass the atrioventricular (AV) node, causing the ventricles
to depolarize earlier than normal (preexcitation). Because the normal delay at the AV
node does not occur, the PR intervals in patients with WPW are usually less than 0.12
seconds (120 ms). When conduction occurs down the AV node and simultaneously
along the bundle of Kent in an anterograde fashion, the two waves of depolarization
,meet (fusion). This manifests on the ECG as a delta wave—slurring or notching at the
beginning of the QRS complex—which may cause QRS widening. The bundle of Kent is
a potential site for a reentry circuit because it allows continued transmission of an
electrical impulse from the atria to the ventricles. Therefore, patients with WPW are
prone to reentry tachycardias—most notably, AV reentry supraventricular tachycardia
(SVT).
✔✔Sudden cardiac arrest in the adult population is MOST often secondary to: - ✔✔A
cardiac dysrhythmia.
Most cases of sudden cardiac arrest (SCA) in the adult population are secondary to a
cardiac dysrhythmia, usually ventricular fibrillation (V-Fib). This fact underscores the
criticality of early defibrillation. Respiratory failure is the most common cause of cardiac
arrest in the pediatric population.
✔✔After performing synchronized cardioversion on an unstable patient with a wide-
complex tachycardia, you look at the monitor and see coarse ventricular fibrillation. The
patient is unresponsive, apneic, and pulseless. You should: - ✔✔Start CPR, ensure the
synchronize mode is off, and defibrillate.
If a patient develops ventricular fibrillation (V-Fib) or pulseless ventricular tachycardia
(V-Tach) following synchronized cardioversion, immediately begin CPR (even if it's just
for a short period of time), ensure that the monitor/defibrillator is not in synchronize
mode, and defibrillate as soon as possible. CPR should be ongoing as the defibrillator is
charging in order to avoid unnecessary delays in performing chest compressions. The
synchronize mode must be turned off prior to defibrillation or the device will not deliver a
shock; this is because there are no R waves to synchronize with in V-Fib. Vascular
access (IV or IO), advanced airway management, and pharmacologic therapy should be
performed during the 2-minute cycles of CPR; they are not an immediate priority during
early cardiac arrest.
✔✔A 70-year-old man presents with an acute onset of confusion, slurred speech, and
left side weakness. According to his daughter, he has high blood pressure and has had
several "small strokes" over the past 6 months. Your partner applies supplemental
oxygen; assesses his vital signs, which are stable; and assesses his blood glucose
level, which reads 35 mg/dL. You attempt to perform the Cincinnati Prehospital Stroke
test, but the patient is unable to understand your instructions. After establishing IV
access, you should: - ✔✔Administer 50% dextrose, monitor his cardiac rhythm, protect
his impaired extremities, and transport.
This patient's clinical presentation and his history of hypertension and transient ischemic
attacks (TIAs) suggest acute ischemic stroke. However, his blood glucose level (BGL) is
significantly low and must be treated. Untreated hypoglycemia may cause irreversible
brain damage or death. Appropriate treatment for this patient involves administering
50% dextrose (consider giving 12.5 g) and then reassessing his BGL to determine the
need for additional glucose. Because the patient is confused, and because some
, patients with acute ischemic stroke lose protective airway reflexes, oral glucose should
be avoided. He may not be able to swallow it, which may result in aspiration. Further
treatment includes protecting his impaired extremities from injury, monitoring his cardiac
rhythm, and transporting him to the hospital. Notify the receiving facility early. Aspirin
should be avoided in the prehospital setting for patients with signs and symptoms of a
stroke. A CT scan of the head must be performed first to rule out intracranial
hemorrhage.
✔✔Which of the following clinical presentations is MOST consistent with an acute
ischemic stroke involving the left cerebral hemisphere? - ✔✔Dysarthria, confusion, right
side hemiparesis, left side facial droop.
Acute ischemic strokes represent approximately 75% of all strokes. Each cerebral
hemisphere controls functions on the contralateral (opposite) side of the body;
therefore, sensory and motor deficits (ie, hemiparesis, hemiparalysis) are observed on
the side of the body opposite the stroke. However, because the facial nerves do not
decussate (cross as they leave the cerebral cortex, move through the brainstem, and
arrive at the spinal cord), facial droop is typically observed on the ipsilateral (same) side
as the stroke. Pupillary changes, if present, will also occur on the same side as the
stroke because of optic nerve crossover in the brain. Other common signs of acute
ischemic stroke include dysarthria (slurred speech), dysphasia (difficulty speaking or
understanding), aphasia (inability to speak or understand), and mental status changes.
In contrast to acute ischemic stroke, acute hemorrhagic stroke (caused by a ruptured
cerebral artery) typically presents with more ominous signs, which include a sudden,
severe headache that is followed by a rapid decline in level of consciousness. Because
bleeding is occurring within the brain, intracranial pressure increases, resulting in signs
such as decorticate (flexor) or decerebrate (extensor) posturing, asymmetric or
bilaterally dilated pupils, and Cushing's triad (hypertension, bradycardia, abnormal
respiratory pattern).
✔✔A 27-year-old female complains of palpitations. The cardiac monitor reveals a
narrow-complex tachycardia at 180/min. She denies any other symptoms, and states
that this has happened to her before, but it typically resolves on its own. Her blood
pressure is 126/66 mm Hg, pulse is 180 beats/min, and respirations are 16 breaths/min.
After attempting vagal maneuvers and giving two doses of adenosine, her cardiac
rhythm and vital signs remain unchanged. You should: - ✔✔Transport at once, reassess
her frequently, and perform synchronized cardioversion if necessary.
Although the patient is in supraventricular tachycardia (SVT), she remains stable
following your initial efforts to slow her heart rate with vagal maneuvers and adenosine.
Her failure to respond to initial treatment does not automatically make her unstable.
Simply transport her, closely monitor her en route, and be prepared to cardiovert her if
she does become unstable (ie, hypotension, altered mental status, chest pain). Unless
specified in your local protocols, pharmacologic therapy beyond adenosine (ie, calcium
channel blockers, amiodarone) is typically not indicated in the field for stable patients
with SVT, although these medications may be given in the emergency department.
AND QUESTIONS SET A+
✔✔Cardioversion involves delivering a shock that is synchronized to occur during the: -
✔✔R wave.
Cardioversion involves delivering a shock that is synchronized to occur during the R
wave, which is when the heart is absolutely refractory. This prevents the shock from
occurring during the relative refractory period (the downslope of the T wave).
Depolarization that occurs during the relative refractory period may induce a non-
perfusing ventricular dysrhythmia, such as pulseless V-Tach or V-Fib. Synchronized
cardioversion is indicated for patients with supraventricular or ventricular tachycardia
who have a pulse, but are hemodynamically unstable.
✔✔Which of the following electrolytes moves slowly into the cardiac cell and maintains
the depolarized state of the cell membrane? - ✔✔Calcium.
The process of depolarization begins as sodium ions rush into the cell. At the same
time, calcium ions enter the cell—albeit more slowly and through specialized
channels—to help maintain the depolarized state of the cell membrane and to supply
calcium ions for contraction of cardiac muscle tissue. During repolarization, the sodium
and calcium channels close, thus stopping the rapid influx of these ions. Then, special
potassium channels open, allowing potassium ions to rapidly exit the cell. This helps
restore the inside of the cell to its negative charge; the proper electrolyte distribution is
then reestablished by pumping sodium ions out of the cell and potassium ions back in.
After the potassium channels close, the sodium-potassium pump helps move sodium
and potassium ions back to their respective locations. For every three sodium ions the
pump moves out of the cell, it moves two potassium ions into the cell, thereby
maintaining the polarity of the cell membrane
✔✔Which of the following cardiac rhythms is associated with bradycardia, and is
characterized by regular R-R intervals and a greater ratio of P waves to QRS
complexes? - ✔✔3rd degree AV block.
,Third-degree AV block is caused by a complete block at the AV node. The SA node
initiates impulses as usual; however, when they reach the AV node, they are blocked.
Resultantly, the ventricles receive no electrical stimulus from the atria, so they initiate
their own impulses, although at a much slower rate. On the ECG, this manifests as a
bradycardic rhythm with more P waves than QRS complexes. The P-P intervals are
regular (some P waves may not be visible because they are buried in a QRS complex),
as are the R-R intervals; however, no relationship exists between a given P wave and
QRS complex. Second-degree AV block type I (Wenkebach) is caused by a progressive
delay at the AV node until an impulse is blocked from entering the ventricles. On the
ECG, this manifests as a progressively lengthening P-R interval until a P wave is
blocked (not followed by a QRS complex). At this point, the R-R interval becomes
irregular, and the presence of this lone P wave increases the ratio of P waves to QRS
complexes. Second-degree AV block type I may or may not be associated with
bradycardia. Second-degree AV block type II is caused by an intermittent block at the
AV node; it occurs when atrial impulses are not conducted to the ventricles. Unlike a
second-degree AV block type I, however, a type II block is characterized by consistent
P-R intervals of the P waves that are conducted. First-degree AV block is an abnormal
delay at the AV node; on the ECG, this manifests with PR intervals greater than 0.20
seconds (120 ms) in duration. In first-degree AV block, all of the atrial impulses are
conducted through the AV node and into the ventricles.
✔✔A 59-year-old male with a monomorphic wide-complex tachycardia at a rate of
220/min, a blood pressure of 80/50 mm Hg, and a decreased level of consciousness,
should be treated with: - ✔✔Synchronized cardioversion.
The patient in this scenario is likely in ventricular tachycardia (V-Tach). Approximately
90% of wide-complex tachycardias are ventricular in origin. Furthermore, he is
hypotensive and has a decreased level of consciousness—signs of hemodynamic
compromise. To prevent his condition from deteriorating further, immediate
synchronized cardioversion, starting with 100 joules, is indicated. Monophasic (or
biphasic equivalent) defibrillation is indicated for patients with pulseless V-Tach and
ventricular fibrillation (V-Fib). Amiodarone (150 mg over 10 minutes) is indicated for
patients with V-Tach who have a pulse, but are hemodynamically stable; it may also be
used as an adjunct for patients with unstable V-Tach when cardioversion alone is not
effective. Magnesium sulfate (1 to 2 g) is indicated for patients with torsade de
pointes—a variant of polymorphic V-Tach.
✔✔ECG indicators of Wolff-Parkinson-White (WPW) syndrome include: - ✔✔Short PR
intervals, delta waves, and QRS widening.
Wolff-Parkinson-White (WPW) syndrome is a condition in which accessory pathways—
called the bundle of Kent—bypass the atrioventricular (AV) node, causing the ventricles
to depolarize earlier than normal (preexcitation). Because the normal delay at the AV
node does not occur, the PR intervals in patients with WPW are usually less than 0.12
seconds (120 ms). When conduction occurs down the AV node and simultaneously
along the bundle of Kent in an anterograde fashion, the two waves of depolarization
,meet (fusion). This manifests on the ECG as a delta wave—slurring or notching at the
beginning of the QRS complex—which may cause QRS widening. The bundle of Kent is
a potential site for a reentry circuit because it allows continued transmission of an
electrical impulse from the atria to the ventricles. Therefore, patients with WPW are
prone to reentry tachycardias—most notably, AV reentry supraventricular tachycardia
(SVT).
✔✔Sudden cardiac arrest in the adult population is MOST often secondary to: - ✔✔A
cardiac dysrhythmia.
Most cases of sudden cardiac arrest (SCA) in the adult population are secondary to a
cardiac dysrhythmia, usually ventricular fibrillation (V-Fib). This fact underscores the
criticality of early defibrillation. Respiratory failure is the most common cause of cardiac
arrest in the pediatric population.
✔✔After performing synchronized cardioversion on an unstable patient with a wide-
complex tachycardia, you look at the monitor and see coarse ventricular fibrillation. The
patient is unresponsive, apneic, and pulseless. You should: - ✔✔Start CPR, ensure the
synchronize mode is off, and defibrillate.
If a patient develops ventricular fibrillation (V-Fib) or pulseless ventricular tachycardia
(V-Tach) following synchronized cardioversion, immediately begin CPR (even if it's just
for a short period of time), ensure that the monitor/defibrillator is not in synchronize
mode, and defibrillate as soon as possible. CPR should be ongoing as the defibrillator is
charging in order to avoid unnecessary delays in performing chest compressions. The
synchronize mode must be turned off prior to defibrillation or the device will not deliver a
shock; this is because there are no R waves to synchronize with in V-Fib. Vascular
access (IV or IO), advanced airway management, and pharmacologic therapy should be
performed during the 2-minute cycles of CPR; they are not an immediate priority during
early cardiac arrest.
✔✔A 70-year-old man presents with an acute onset of confusion, slurred speech, and
left side weakness. According to his daughter, he has high blood pressure and has had
several "small strokes" over the past 6 months. Your partner applies supplemental
oxygen; assesses his vital signs, which are stable; and assesses his blood glucose
level, which reads 35 mg/dL. You attempt to perform the Cincinnati Prehospital Stroke
test, but the patient is unable to understand your instructions. After establishing IV
access, you should: - ✔✔Administer 50% dextrose, monitor his cardiac rhythm, protect
his impaired extremities, and transport.
This patient's clinical presentation and his history of hypertension and transient ischemic
attacks (TIAs) suggest acute ischemic stroke. However, his blood glucose level (BGL) is
significantly low and must be treated. Untreated hypoglycemia may cause irreversible
brain damage or death. Appropriate treatment for this patient involves administering
50% dextrose (consider giving 12.5 g) and then reassessing his BGL to determine the
need for additional glucose. Because the patient is confused, and because some
, patients with acute ischemic stroke lose protective airway reflexes, oral glucose should
be avoided. He may not be able to swallow it, which may result in aspiration. Further
treatment includes protecting his impaired extremities from injury, monitoring his cardiac
rhythm, and transporting him to the hospital. Notify the receiving facility early. Aspirin
should be avoided in the prehospital setting for patients with signs and symptoms of a
stroke. A CT scan of the head must be performed first to rule out intracranial
hemorrhage.
✔✔Which of the following clinical presentations is MOST consistent with an acute
ischemic stroke involving the left cerebral hemisphere? - ✔✔Dysarthria, confusion, right
side hemiparesis, left side facial droop.
Acute ischemic strokes represent approximately 75% of all strokes. Each cerebral
hemisphere controls functions on the contralateral (opposite) side of the body;
therefore, sensory and motor deficits (ie, hemiparesis, hemiparalysis) are observed on
the side of the body opposite the stroke. However, because the facial nerves do not
decussate (cross as they leave the cerebral cortex, move through the brainstem, and
arrive at the spinal cord), facial droop is typically observed on the ipsilateral (same) side
as the stroke. Pupillary changes, if present, will also occur on the same side as the
stroke because of optic nerve crossover in the brain. Other common signs of acute
ischemic stroke include dysarthria (slurred speech), dysphasia (difficulty speaking or
understanding), aphasia (inability to speak or understand), and mental status changes.
In contrast to acute ischemic stroke, acute hemorrhagic stroke (caused by a ruptured
cerebral artery) typically presents with more ominous signs, which include a sudden,
severe headache that is followed by a rapid decline in level of consciousness. Because
bleeding is occurring within the brain, intracranial pressure increases, resulting in signs
such as decorticate (flexor) or decerebrate (extensor) posturing, asymmetric or
bilaterally dilated pupils, and Cushing's triad (hypertension, bradycardia, abnormal
respiratory pattern).
✔✔A 27-year-old female complains of palpitations. The cardiac monitor reveals a
narrow-complex tachycardia at 180/min. She denies any other symptoms, and states
that this has happened to her before, but it typically resolves on its own. Her blood
pressure is 126/66 mm Hg, pulse is 180 beats/min, and respirations are 16 breaths/min.
After attempting vagal maneuvers and giving two doses of adenosine, her cardiac
rhythm and vital signs remain unchanged. You should: - ✔✔Transport at once, reassess
her frequently, and perform synchronized cardioversion if necessary.
Although the patient is in supraventricular tachycardia (SVT), she remains stable
following your initial efforts to slow her heart rate with vagal maneuvers and adenosine.
Her failure to respond to initial treatment does not automatically make her unstable.
Simply transport her, closely monitor her en route, and be prepared to cardiovert her if
she does become unstable (ie, hypotension, altered mental status, chest pain). Unless
specified in your local protocols, pharmacologic therapy beyond adenosine (ie, calcium
channel blockers, amiodarone) is typically not indicated in the field for stable patients
with SVT, although these medications may be given in the emergency department.
