, Question 1
During continuous telemetry monitoring, a patient's rhythm strip shows a
narrow-complex tachycardia at 168 bpm with sudden onset and termination.
Which maneuver or intervention is most appropriate as the initial diagnostic
and therapeutic step, assuming the patient is hemodynamically stable?
A. Administer intravenous adenosine 6 mg rapid push
B. Perform carotid sinus massage after ruling out carotid bruits
C. Initiate synchronized cardioversion at 50 J
D. Administer intravenous amiodarone 150 mg over 10 minutes
Correct Answer: B - Perform carotid sinus massage after ruling
out carotid bruits
RATIONALE
For stable narrow-complex tachycardia, vagal maneuvers (e.g., carotid
sinus massage) are first-line per ACLS guidelines. Adenosine is used
if vagal maneuvers fail, but it is not the initial step. Cardioversion is
reserved for unstable patients, and amiodarone is for wide-complex or
refractory rhythms.
Question 2
Which of the following best explains why the unipolar lead aVR is often
overlooked in telemetry monitoring despite its diagnostic value in detecting left
main coronary artery occlusion?
A. aVR is a unipolar lead that primarily reflects right ventricular activity,
limiting its sensitivity for left-sided ischemia.
B. aVR is frequently inverted on standard telemetry displays, making
ST-segment changes difficult to interpret.
C. aVR is a reciprocal lead that typically shows ST depression in left
main disease, which is often dismissed as nonspecific.
D. aVR is not included in standard 5-lead telemetry systems, so its data is
unavailable.
Page 2
,Correct Answer: C - aVR is a reciprocal lead that typically shows
ST depression in left main disease, which is often dismissed as
nonspecific.
RATIONALE
In left main coronary occlusion, aVR often shows ST elevation, but
reciprocal ST depression in other leads may overshadow it. Clinicians
may dismiss aVR changes as nonspecific, missing its diagnostic value.
aVR is included in 5-lead systems, and it reflects global left
ventricular ischemia, not right ventricular activity.
Question 3
A telemetry monitor shows a regular rhythm at 75 bpm with a PR interval of
0.28 seconds and a QRS duration of 0.12 seconds. The patient is
asymptomatic. Which of the following is the most likely underlying
electrophysiologic disturbance?
A. Enhanced vagal tone at the AV node
B. Delayed conduction through the His-Purkinje system
C. Concealed conduction in the AV node
D. Accelerated junctional rhythm with aberrancy
Correct Answer: B - Delayed conduction through the
His-Purkinje system
RATIONALE
A PR interval >0.20 s with a wide QRS suggests conduction delay
below the AV node, likely in the His-Purkinje system (e.g.,
bifascicular block). Enhanced vagal tone typically prolongs PR
without widening QRS. Concealed conduction and accelerated
junctional rhythm do not fit the regular sinus pattern with first-degree
AV block and bundle branch block.
Page 3
, Question 4
When interpreting a telemetry strip, which of the following features most
reliably distinguishes ventricular tachycardia (VT) from supraventricular
tachycardia (SVT) with aberrancy?
A. Presence of AV dissociation
B. Heart rate >150 bpm
C. Regularity of the rhythm
D. Response to adenosine
Correct Answer: A - Presence of AV dissociation
RATIONALE
AV dissociation is a hallmark of VT and is highly specific, though not
always present. Heart rate and regularity overlap between VT and
SVT with aberrancy. Adenosine response is not reliable for
differentiation and may be dangerous in VT.
Question 5
A patient on telemetry develops a rhythm with a sawtooth pattern at 300 bpm
and a ventricular rate of 150 bpm. The QRS is narrow. Which of the following
is the most appropriate immediate management?
A. Administer intravenous adenosine 6 mg
B. Perform synchronized cardioversion at 100 J
C. Administer intravenous diltiazem 0.25 mg/kg
D. Initiate vagal maneuvers
Correct Answer: C - Administer intravenous diltiazem 0.25
mg/kg
Page 4
During continuous telemetry monitoring, a patient's rhythm strip shows a
narrow-complex tachycardia at 168 bpm with sudden onset and termination.
Which maneuver or intervention is most appropriate as the initial diagnostic
and therapeutic step, assuming the patient is hemodynamically stable?
A. Administer intravenous adenosine 6 mg rapid push
B. Perform carotid sinus massage after ruling out carotid bruits
C. Initiate synchronized cardioversion at 50 J
D. Administer intravenous amiodarone 150 mg over 10 minutes
Correct Answer: B - Perform carotid sinus massage after ruling
out carotid bruits
RATIONALE
For stable narrow-complex tachycardia, vagal maneuvers (e.g., carotid
sinus massage) are first-line per ACLS guidelines. Adenosine is used
if vagal maneuvers fail, but it is not the initial step. Cardioversion is
reserved for unstable patients, and amiodarone is for wide-complex or
refractory rhythms.
Question 2
Which of the following best explains why the unipolar lead aVR is often
overlooked in telemetry monitoring despite its diagnostic value in detecting left
main coronary artery occlusion?
A. aVR is a unipolar lead that primarily reflects right ventricular activity,
limiting its sensitivity for left-sided ischemia.
B. aVR is frequently inverted on standard telemetry displays, making
ST-segment changes difficult to interpret.
C. aVR is a reciprocal lead that typically shows ST depression in left
main disease, which is often dismissed as nonspecific.
D. aVR is not included in standard 5-lead telemetry systems, so its data is
unavailable.
Page 2
,Correct Answer: C - aVR is a reciprocal lead that typically shows
ST depression in left main disease, which is often dismissed as
nonspecific.
RATIONALE
In left main coronary occlusion, aVR often shows ST elevation, but
reciprocal ST depression in other leads may overshadow it. Clinicians
may dismiss aVR changes as nonspecific, missing its diagnostic value.
aVR is included in 5-lead systems, and it reflects global left
ventricular ischemia, not right ventricular activity.
Question 3
A telemetry monitor shows a regular rhythm at 75 bpm with a PR interval of
0.28 seconds and a QRS duration of 0.12 seconds. The patient is
asymptomatic. Which of the following is the most likely underlying
electrophysiologic disturbance?
A. Enhanced vagal tone at the AV node
B. Delayed conduction through the His-Purkinje system
C. Concealed conduction in the AV node
D. Accelerated junctional rhythm with aberrancy
Correct Answer: B - Delayed conduction through the
His-Purkinje system
RATIONALE
A PR interval >0.20 s with a wide QRS suggests conduction delay
below the AV node, likely in the His-Purkinje system (e.g.,
bifascicular block). Enhanced vagal tone typically prolongs PR
without widening QRS. Concealed conduction and accelerated
junctional rhythm do not fit the regular sinus pattern with first-degree
AV block and bundle branch block.
Page 3
, Question 4
When interpreting a telemetry strip, which of the following features most
reliably distinguishes ventricular tachycardia (VT) from supraventricular
tachycardia (SVT) with aberrancy?
A. Presence of AV dissociation
B. Heart rate >150 bpm
C. Regularity of the rhythm
D. Response to adenosine
Correct Answer: A - Presence of AV dissociation
RATIONALE
AV dissociation is a hallmark of VT and is highly specific, though not
always present. Heart rate and regularity overlap between VT and
SVT with aberrancy. Adenosine response is not reliable for
differentiation and may be dangerous in VT.
Question 5
A patient on telemetry develops a rhythm with a sawtooth pattern at 300 bpm
and a ventricular rate of 150 bpm. The QRS is narrow. Which of the following
is the most appropriate immediate management?
A. Administer intravenous adenosine 6 mg
B. Perform synchronized cardioversion at 100 J
C. Administer intravenous diltiazem 0.25 mg/kg
D. Initiate vagal maneuvers
Correct Answer: C - Administer intravenous diltiazem 0.25
mg/kg
Page 4
