CARDIOLOGY FISDAP 2 REVISION HANDBOOK
2026 CARDIAC PHYSIOLOGY AND
DYSRHYTHMIA RECOGNITION
◉ ECG indicators of Wolff-Parkinson-White (WPW) syndrome
include:
Answer: 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:
Answer: 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:
Answer: 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:
Answer: 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?
Answer: 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
2026 CARDIAC PHYSIOLOGY AND
DYSRHYTHMIA RECOGNITION
◉ ECG indicators of Wolff-Parkinson-White (WPW) syndrome
include:
Answer: 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:
Answer: 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:
Answer: 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:
Answer: 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?
Answer: 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
