2026 APEX EKG TEST EXAM – QUESTIONS WITH
CORRECT ANSWERS & RATIONALES | Master ECG
Interpretation for Nursing & Cardiology Certification
Accelerate your cardiac rhythm recognition and pass your
certification with this definitive APEX EKG test preparation
guide packed with real questions, answers, and detailed
rationales. This comprehensive resource covers EKG grid
calculations, interval measurements, advanced cardiac
electrophysiology, and complex arrhythmia interpretation
(including heart blocks, AFib, and telemetry monitoring). It
is an essential study tool for nursing students and
telemetry professionals looking to secure a top grade and
clinical confidence
QUESTION 1
What is the normal axis range for a healthy adult heart?
A) -30 to +90 degrees
B) -30 to +90 degrees (0 to +90 is typical)
C) 0 to +180 degrees
D) -90 to +90 degrees
Answer: B) -30 to +90 degrees
Rationale: The normal QRS axis in adults ranges from -30 to +90 degrees,
with 0 to +90 being the most common. Left axis deviation is defined as an
axis less than -30 degrees, and right axis deviation is greater than +90
degrees .
,QUESTION 2
Left axis deviation is most commonly associated with which condition?
A) Right ventricular hypertrophy
B) Left ventricular hypertrophy
C) Pulmonary embolism
D) Lateral wall MI
Answer: B) Left ventricular hypertrophy
Rationale: Left axis deviation is most commonly associated with left
ventricular hypertrophy (LVH), left anterior fascicular block (LAFB), and
inferior wall myocardial infarction. It occurs when the electrical axis shifts to
the left due to left ventricular dominance .
QUESTION 3
Right axis deviation is most commonly associated with which
condition?
A) Left ventricular hypertrophy
B) Right ventricular hypertrophy
C) Anterior wall MI
D) Hyperkalemia
Answer: B) Right ventricular hypertrophy
Rationale: Right axis deviation is commonly seen in right ventricular
hypertrophy (RVH), pulmonary embolism, lateral wall MI, and left posterior
fascicular block (LPFB). It occurs when the electrical axis shifts to the right due
to right ventricular dominance .
,QUESTION 4
What is the significance of an extreme axis deviation (Northwest axis)?
A) Normal variant
B) Ventricular tachycardia or severe conduction abnormality
C) Left ventricular hypertrophy
D) Pulmonary embolism
Answer: B) Ventricular tachycardia or severe conduction abnormality
Rationale: Extreme axis deviation (axis between -90 and -180 degrees, also
called Northwest axis) suggests ventricular tachycardia, severe hyperkalemia,
or an intraventricular conduction defect. This finding requires prompt clinical
correlation .
QUESTION 5
The S1Q3T3 pattern is most suggestive of which condition?
A) Acute myocardial infarction
B) Pulmonary embolism
C) Pericarditis
D) Hyperkalemia
Answer: B) Pulmonary embolism
Rationale: The S1Q3T3 pattern (S wave in lead I, Q wave and inverted T
wave in lead III) is the classic ECG finding in pulmonary embolism, indicating
right heart strain. This pattern is seen in approximately 20-30% of patients
with acute pulmonary embolism .
, QUESTION 6
What is the characteristic ECG change associated with Wellens
syndrome?
A) ST elevation in V1-V4
B) Biphasic or deeply inverted T waves in V2-V3
C) Peaked T waves
D) Delta waves
Answer: B) Biphasic or deeply inverted T waves in V2-V3
Rationale: Wellens syndrome is a pattern of deeply inverted or biphasic T
waves in leads V2-V3, indicating critical stenosis of the left anterior
descending (LAD) coronary artery. It is a precursor to anterior wall ST-
elevation myocardial infarction .
QUESTION 7
What is the most common ECG finding in Wellens syndrome?
A) ST elevation in V2-V3
B) Deep T wave inversion in V2-V3
C) Pathologic Q waves
D) Short PR interval
Answer: B) Deep T wave inversion in V2-V3
Rationale: Wellens syndrome is characterized by biphasic or deeply inverted
T waves in leads V2 and V3 (Type A = biphasic, Type B = deep inverted). It is
associated with high-grade stenosis of the proximal LAD coronary artery and
requires urgent intervention .
CORRECT ANSWERS & RATIONALES | Master ECG
Interpretation for Nursing & Cardiology Certification
Accelerate your cardiac rhythm recognition and pass your
certification with this definitive APEX EKG test preparation
guide packed with real questions, answers, and detailed
rationales. This comprehensive resource covers EKG grid
calculations, interval measurements, advanced cardiac
electrophysiology, and complex arrhythmia interpretation
(including heart blocks, AFib, and telemetry monitoring). It
is an essential study tool for nursing students and
telemetry professionals looking to secure a top grade and
clinical confidence
QUESTION 1
What is the normal axis range for a healthy adult heart?
A) -30 to +90 degrees
B) -30 to +90 degrees (0 to +90 is typical)
C) 0 to +180 degrees
D) -90 to +90 degrees
Answer: B) -30 to +90 degrees
Rationale: The normal QRS axis in adults ranges from -30 to +90 degrees,
with 0 to +90 being the most common. Left axis deviation is defined as an
axis less than -30 degrees, and right axis deviation is greater than +90
degrees .
,QUESTION 2
Left axis deviation is most commonly associated with which condition?
A) Right ventricular hypertrophy
B) Left ventricular hypertrophy
C) Pulmonary embolism
D) Lateral wall MI
Answer: B) Left ventricular hypertrophy
Rationale: Left axis deviation is most commonly associated with left
ventricular hypertrophy (LVH), left anterior fascicular block (LAFB), and
inferior wall myocardial infarction. It occurs when the electrical axis shifts to
the left due to left ventricular dominance .
QUESTION 3
Right axis deviation is most commonly associated with which
condition?
A) Left ventricular hypertrophy
B) Right ventricular hypertrophy
C) Anterior wall MI
D) Hyperkalemia
Answer: B) Right ventricular hypertrophy
Rationale: Right axis deviation is commonly seen in right ventricular
hypertrophy (RVH), pulmonary embolism, lateral wall MI, and left posterior
fascicular block (LPFB). It occurs when the electrical axis shifts to the right due
to right ventricular dominance .
,QUESTION 4
What is the significance of an extreme axis deviation (Northwest axis)?
A) Normal variant
B) Ventricular tachycardia or severe conduction abnormality
C) Left ventricular hypertrophy
D) Pulmonary embolism
Answer: B) Ventricular tachycardia or severe conduction abnormality
Rationale: Extreme axis deviation (axis between -90 and -180 degrees, also
called Northwest axis) suggests ventricular tachycardia, severe hyperkalemia,
or an intraventricular conduction defect. This finding requires prompt clinical
correlation .
QUESTION 5
The S1Q3T3 pattern is most suggestive of which condition?
A) Acute myocardial infarction
B) Pulmonary embolism
C) Pericarditis
D) Hyperkalemia
Answer: B) Pulmonary embolism
Rationale: The S1Q3T3 pattern (S wave in lead I, Q wave and inverted T
wave in lead III) is the classic ECG finding in pulmonary embolism, indicating
right heart strain. This pattern is seen in approximately 20-30% of patients
with acute pulmonary embolism .
, QUESTION 6
What is the characteristic ECG change associated with Wellens
syndrome?
A) ST elevation in V1-V4
B) Biphasic or deeply inverted T waves in V2-V3
C) Peaked T waves
D) Delta waves
Answer: B) Biphasic or deeply inverted T waves in V2-V3
Rationale: Wellens syndrome is a pattern of deeply inverted or biphasic T
waves in leads V2-V3, indicating critical stenosis of the left anterior
descending (LAD) coronary artery. It is a precursor to anterior wall ST-
elevation myocardial infarction .
QUESTION 7
What is the most common ECG finding in Wellens syndrome?
A) ST elevation in V2-V3
B) Deep T wave inversion in V2-V3
C) Pathologic Q waves
D) Short PR interval
Answer: B) Deep T wave inversion in V2-V3
Rationale: Wellens syndrome is characterized by biphasic or deeply inverted
T waves in leads V2 and V3 (Type A = biphasic, Type B = deep inverted). It is
associated with high-grade stenosis of the proximal LAD coronary artery and
requires urgent intervention .
