APEX EKG Test - 41 Questions with Detailed Solutions & Diagrams |
Complete Rhythm Interpretation Board Review 2026
Master complex cardiac electrophysiology and pass your assessment with this premium
APEX EKG test preparation bank featuring 41 high-yield practice questions. This
comprehensive study guide includes 100% verified solutions and detailed diagnostic
diagrams covering EKG grid calculations, interval measurements, and critical cardiac
arrhythmia identification. It is the ultimate tool for telemetry nurses, nursing students,
and cardiology professionals looking to build clinical confidence and secure an A+
grade.
1. A 55-year-old male with alcoholic cirrhosis develops ascites and is started on
torsemide. Which pharmacokinetic advantage does torsemide have over
furosemide in patients with hepatic impairment?
A) Shorter half-life requiring less frequent dosing
B) Higher oral bioavailability (80-100%) unaffected by hepatic metabolism
C) No effect on potassium levels
D) Exclusively renally eliminated
Correct Answer: B) Higher oral bioavailability (80-100%) unaffected by hepatic
metabolism
Rationale: Torsemide has excellent oral bioavailability (80-100%) compared to furosemide
(40-60%), making it more reliable in patients with hepatic congestion and impaired
absorption.
2. A 42-year-old woman with systemic lupus erythematosus is started on
belimumab. Which specific target does this monoclonal antibody bind to in the
treatment of SLE?
A) CD20 on B cells
B) B-lymphocyte stimulator (BLyS)
C) TNF-alpha
D) IL-6 receptor
Correct Answer: B) B-lymphocyte stimulator (BLyS)
Rationale: Belimumab is a monoclonal antibody that specifically binds to soluble B-
lymphocyte stimulator (BLyS/BAFF), reducing B-cell survival and autoantibody production
in SLE.
,3. A patient with chronic constipation and irritable bowel syndrome is started on
plecanatide. Which receptor does this guanylate cyclase-C agonist activate in the
intestinal epithelium?
A) CFTR chloride channel
B) Guanylate cyclase-C receptor
C) 5-HT4 receptor
D) Muscarinic M3 receptor
Correct Answer: B) Guanylate cyclase-C receptor
Rationale: Plecanatide activates guanylate cyclase-C receptors on intestinal epithelial cells,
increasing cGMP production, which stimulates fluid secretion and accelerates intestinal
transit.
4. A 60-year-old patient with heart failure with preserved ejection fraction is
started on vericiguat. What is the mechanism of action of this novel heart failure
medication?
A) Neprilysin inhibition
B) Soluble guanylate cyclase stimulation
C) Sodium-glucose cotransporter inhibition
D) Cardiac myosin activation
Correct Answer: B) Soluble guanylate cyclase stimulation
Rationale: Vericiguat directly stimulates soluble guanylate cyclase, increasing cGMP
production even in the absence of nitric oxide, promoting vasodilation and improving
cardiac function in HFpEF.
5. A 45-year-old male with acromegaly is started on pasireotide. Which receptor
affinity profile distinguishes this somatostatin analogue from octreotide?
A) Exclusive SSTR2 affinity
B) Broad SSTR1, SSTR2, SSTR3, SSTR5 affinity
C) Exclusive SSTR5 affinity
D) SSTR2 and SSTR5 affinity
Correct Answer: B) Broad SSTR1, SSTR2, SSTR3, SSTR5 affinity
Rationale: Pasireotide has high affinity for multiple somatostatin receptor subtypes (SSTR1,
SSTR2, SSTR3, SSTR5), making it effective in acromegaly patients who are resistant to
octreotide (which primarily targets SSTR2).
,6. A patient with refractory status epilepticus is started on ketamine. Which
receptor does this dissociative anesthetic primarily antagonize to produce its
anticonvulsant effect?
A) GABA-A receptor
B) NMDA receptor
C) AMPA receptor
D) Glycine receptor
Correct Answer: B) NMDA receptor
Rationale: Ketamine is a non-competitive NMDA receptor antagonist used in refractory
status epilepticus, reducing excitotoxicity and seizure activity through glutamate pathway
modulation.
7. A 50-year-old woman with postmenopausal osteoporosis is started on
romosozumab. Which dual mechanism of action makes this monoclonal antibody
unique among osteoporosis treatments?
A) PTH receptor agonism and RANKL inhibition
B) Sclerostin inhibition with both anabolic and antiresorptive effects
C) Estrogen receptor modulation and calcium sensing
D) Selective estrogen receptor modulator and bisphosphonate combination
Correct Answer: B) Sclerostin inhibition with both anabolic and antiresorptive
effects
Rationale: Romosozumab inhibits sclerostin, a Wnt signaling antagonist, leading to rapid
bone formation (anabolic) and decreased bone resorption (antiresorptive), providing
greater fracture reduction than alendronate.
8. A 38-year-old male with treatment-resistant depression is started on
esketamine. What is the recommended administration route and monitoring
requirement for this medication?
A) Oral daily with routine blood monitoring
B) Intranasal twice weekly with blood pressure monitoring for 2 hours post-dose
C) Intravenous weekly with cardiac monitoring
D) Subcutaneous daily with seizure monitoring
Correct Answer: B) Intranasal twice weekly with blood pressure monitoring for 2
hours post-dose
Rationale: Esketamine is administered intranasally twice weekly under REMS requirements,
, with mandatory blood pressure monitoring for at least 2 hours due to transient but
significant BP increases.
9. A 55-year-old diabetic patient with neuropathic pain is started on duloxetine.
What is the maximum recommended daily dose for diabetic peripheral neuropathy
based on clinical guidelines?
A) 30 mg daily
B) 60 mg daily
C) 120 mg daily
D) 150 mg daily
Correct Answer: B) 60 mg daily
Rationale: Duloxetine for diabetic peripheral neuropathy is dosed at 60 mg daily (may
start at 30 mg), with no additional benefit at higher doses; maximum recommended dose
is 60 mg for this indication.
10. A patient with rheumatoid arthritis is started on baricitinib. Which laboratory
monitoring is specifically recommended due to the mechanism of JAK inhibition?
A) Complete blood count, LFTs, and lipid profile
B) Serum creatinine and BUN
C) Troponin and BNP
D) TSH and free T4
Correct Answer: A) Complete blood count, LFTs, and lipid profile
Rationale: Baricitinib (JAK inhibitor) requires monitoring of CBC (neutropenia,
thrombocytopenia), LFTs (hepatotoxicity), and lipid profile (increased LDL/HDL) at baseline
and periodically during therapy.
11. A 62-year-old patient with symptomatic bradycardia and heart failure is
started on ivabradine. Which ion channel does this drug block to reduce heart
rate?
A) L-type calcium channels
B) Funny current (If) channels in the sinoatrial node
C) Potassium channels in the ventricle
D) Sodium channels in the atria
Correct Answer: B) Funny current (If) channels in the sinoatrial node
Rationale: Ivabradine selectively and specifically inhibits the hyperpolarization-activated
Complete Rhythm Interpretation Board Review 2026
Master complex cardiac electrophysiology and pass your assessment with this premium
APEX EKG test preparation bank featuring 41 high-yield practice questions. This
comprehensive study guide includes 100% verified solutions and detailed diagnostic
diagrams covering EKG grid calculations, interval measurements, and critical cardiac
arrhythmia identification. It is the ultimate tool for telemetry nurses, nursing students,
and cardiology professionals looking to build clinical confidence and secure an A+
grade.
1. A 55-year-old male with alcoholic cirrhosis develops ascites and is started on
torsemide. Which pharmacokinetic advantage does torsemide have over
furosemide in patients with hepatic impairment?
A) Shorter half-life requiring less frequent dosing
B) Higher oral bioavailability (80-100%) unaffected by hepatic metabolism
C) No effect on potassium levels
D) Exclusively renally eliminated
Correct Answer: B) Higher oral bioavailability (80-100%) unaffected by hepatic
metabolism
Rationale: Torsemide has excellent oral bioavailability (80-100%) compared to furosemide
(40-60%), making it more reliable in patients with hepatic congestion and impaired
absorption.
2. A 42-year-old woman with systemic lupus erythematosus is started on
belimumab. Which specific target does this monoclonal antibody bind to in the
treatment of SLE?
A) CD20 on B cells
B) B-lymphocyte stimulator (BLyS)
C) TNF-alpha
D) IL-6 receptor
Correct Answer: B) B-lymphocyte stimulator (BLyS)
Rationale: Belimumab is a monoclonal antibody that specifically binds to soluble B-
lymphocyte stimulator (BLyS/BAFF), reducing B-cell survival and autoantibody production
in SLE.
,3. A patient with chronic constipation and irritable bowel syndrome is started on
plecanatide. Which receptor does this guanylate cyclase-C agonist activate in the
intestinal epithelium?
A) CFTR chloride channel
B) Guanylate cyclase-C receptor
C) 5-HT4 receptor
D) Muscarinic M3 receptor
Correct Answer: B) Guanylate cyclase-C receptor
Rationale: Plecanatide activates guanylate cyclase-C receptors on intestinal epithelial cells,
increasing cGMP production, which stimulates fluid secretion and accelerates intestinal
transit.
4. A 60-year-old patient with heart failure with preserved ejection fraction is
started on vericiguat. What is the mechanism of action of this novel heart failure
medication?
A) Neprilysin inhibition
B) Soluble guanylate cyclase stimulation
C) Sodium-glucose cotransporter inhibition
D) Cardiac myosin activation
Correct Answer: B) Soluble guanylate cyclase stimulation
Rationale: Vericiguat directly stimulates soluble guanylate cyclase, increasing cGMP
production even in the absence of nitric oxide, promoting vasodilation and improving
cardiac function in HFpEF.
5. A 45-year-old male with acromegaly is started on pasireotide. Which receptor
affinity profile distinguishes this somatostatin analogue from octreotide?
A) Exclusive SSTR2 affinity
B) Broad SSTR1, SSTR2, SSTR3, SSTR5 affinity
C) Exclusive SSTR5 affinity
D) SSTR2 and SSTR5 affinity
Correct Answer: B) Broad SSTR1, SSTR2, SSTR3, SSTR5 affinity
Rationale: Pasireotide has high affinity for multiple somatostatin receptor subtypes (SSTR1,
SSTR2, SSTR3, SSTR5), making it effective in acromegaly patients who are resistant to
octreotide (which primarily targets SSTR2).
,6. A patient with refractory status epilepticus is started on ketamine. Which
receptor does this dissociative anesthetic primarily antagonize to produce its
anticonvulsant effect?
A) GABA-A receptor
B) NMDA receptor
C) AMPA receptor
D) Glycine receptor
Correct Answer: B) NMDA receptor
Rationale: Ketamine is a non-competitive NMDA receptor antagonist used in refractory
status epilepticus, reducing excitotoxicity and seizure activity through glutamate pathway
modulation.
7. A 50-year-old woman with postmenopausal osteoporosis is started on
romosozumab. Which dual mechanism of action makes this monoclonal antibody
unique among osteoporosis treatments?
A) PTH receptor agonism and RANKL inhibition
B) Sclerostin inhibition with both anabolic and antiresorptive effects
C) Estrogen receptor modulation and calcium sensing
D) Selective estrogen receptor modulator and bisphosphonate combination
Correct Answer: B) Sclerostin inhibition with both anabolic and antiresorptive
effects
Rationale: Romosozumab inhibits sclerostin, a Wnt signaling antagonist, leading to rapid
bone formation (anabolic) and decreased bone resorption (antiresorptive), providing
greater fracture reduction than alendronate.
8. A 38-year-old male with treatment-resistant depression is started on
esketamine. What is the recommended administration route and monitoring
requirement for this medication?
A) Oral daily with routine blood monitoring
B) Intranasal twice weekly with blood pressure monitoring for 2 hours post-dose
C) Intravenous weekly with cardiac monitoring
D) Subcutaneous daily with seizure monitoring
Correct Answer: B) Intranasal twice weekly with blood pressure monitoring for 2
hours post-dose
Rationale: Esketamine is administered intranasally twice weekly under REMS requirements,
, with mandatory blood pressure monitoring for at least 2 hours due to transient but
significant BP increases.
9. A 55-year-old diabetic patient with neuropathic pain is started on duloxetine.
What is the maximum recommended daily dose for diabetic peripheral neuropathy
based on clinical guidelines?
A) 30 mg daily
B) 60 mg daily
C) 120 mg daily
D) 150 mg daily
Correct Answer: B) 60 mg daily
Rationale: Duloxetine for diabetic peripheral neuropathy is dosed at 60 mg daily (may
start at 30 mg), with no additional benefit at higher doses; maximum recommended dose
is 60 mg for this indication.
10. A patient with rheumatoid arthritis is started on baricitinib. Which laboratory
monitoring is specifically recommended due to the mechanism of JAK inhibition?
A) Complete blood count, LFTs, and lipid profile
B) Serum creatinine and BUN
C) Troponin and BNP
D) TSH and free T4
Correct Answer: A) Complete blood count, LFTs, and lipid profile
Rationale: Baricitinib (JAK inhibitor) requires monitoring of CBC (neutropenia,
thrombocytopenia), LFTs (hepatotoxicity), and lipid profile (increased LDL/HDL) at baseline
and periodically during therapy.
11. A 62-year-old patient with symptomatic bradycardia and heart failure is
started on ivabradine. Which ion channel does this drug block to reduce heart
rate?
A) L-type calcium channels
B) Funny current (If) channels in the sinoatrial node
C) Potassium channels in the ventricle
D) Sodium channels in the atria
Correct Answer: B) Funny current (If) channels in the sinoatrial node
Rationale: Ivabradine selectively and specifically inhibits the hyperpolarization-activated
