COMSAE Phase 6 Clinical Sciences
Practice Exam 2026 Edition Questions
with Answers and Detailed Rationales
1.
A 64-year-old man presents with crushing substernal chest
pain that began 45 minutes ago while he was mowing his
lawn. ECG demonstrates ST-segment elevation in leads II, III,
and aVF. Blood pressure is 86/58 mm Hg, and jugular venous
pressure is elevated. The lungs are clear. Which coronary
artery is most likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Left main coronary artery
Answer: C. Right coronary artery
An inferior myocardial infarction with hypotension, elevated
JVP, and clear lungs suggests right ventricular infarction, most
commonly caused by right coronary artery occlusion. The
right ventricle is preload dependent, so aggressive nitrate
administration can worsen hypotension.
2.
,A 27-year-old woman develops sudden pleuritic chest pain
and dyspnea 5 days after undergoing knee surgery. She is
tachycardic and mildly hypoxemic. CT pulmonary angiography
demonstrates a filling defect in a segmental pulmonary
artery. Which finding would most likely be present on ECG?
A. ST-segment elevation in leads V1–V4
B. S1Q3T3 pattern
C. Prolonged PR interval
D. Diffuse ST-segment depression
Answer: B. S1Q3T3 pattern
Acute pulmonary embolism can produce right ventricular
strain, classically reflected by an S1Q3T3 pattern, although
sinus tachycardia is more common. The clinical setting of
recent surgery and acute pleuritic symptoms strongly
supports venous thromboembolism.
3.
A 58-year-old man with hypertension has progressive
exertional dyspnea and orthopnea. Echocardiography reveals
an ejection fraction of 30%. Which medication class improves
survival in patients with chronic systolic heart failure?
A. Loop diuretics
B. ACE inhibitors
C. Digoxin
D. Nitrates alone
Answer: B. ACE inhibitors
,ACE inhibitors reduce afterload, limit adverse ventricular
remodeling, and decrease mortality in heart failure with
reduced ejection fraction. Loop diuretics primarily provide
symptomatic relief without a demonstrated mortality benefit.
4.
A 72-year-old woman presents with palpitations and
dizziness. ECG demonstrates an irregularly irregular rhythm
with no discernible P waves. Which complication is she at
greatest risk of developing?
A. Ventricular septal rupture
B. Ischemic stroke
C. Complete heart block
D. Infective endocarditis
Answer: B. Ischemic stroke
Atrial fibrillation promotes blood stasis in the left atrial
appendage, increasing the risk of thromboembolic stroke.
Stroke prevention is determined by the patient's
thromboembolic risk and may require anticoagulation.
5.
A 35-year-old man presents with fever, weight loss, night
sweats, and a new murmur. He has a history of injection drug
use. Blood cultures grow Staphylococcus aureus. Which
cardiac valve is most likely affected?
, A. Aortic
B. Mitral
C. Tricuspid
D. Pulmonic
Answer: C. Tricuspid
Injection drug use is strongly associated with right-sided
infective endocarditis, particularly involving the tricuspid
valve. S. aureus is the most common causative organism.
6.
A 69-year-old man with a 50-pack-year smoking history
presents with chronic cough and progressive dyspnea.
Pulmonary function testing shows a reduced FEV1/FVC ratio
and increased total lung capacity. Which diagnosis is most
likely?
A. Pulmonary fibrosis
B. Emphysema
C. Restrictive chest wall disease
D. Sarcoidosis
Answer: B. Emphysema
Emphysema causes obstructive physiology with reduced
FEV1/FVC and hyperinflation. Destruction of alveolar walls
decreases elastic recoil and increases lung compliance.
7.
Practice Exam 2026 Edition Questions
with Answers and Detailed Rationales
1.
A 64-year-old man presents with crushing substernal chest
pain that began 45 minutes ago while he was mowing his
lawn. ECG demonstrates ST-segment elevation in leads II, III,
and aVF. Blood pressure is 86/58 mm Hg, and jugular venous
pressure is elevated. The lungs are clear. Which coronary
artery is most likely occluded?
A. Left anterior descending artery
B. Left circumflex artery
C. Right coronary artery
D. Left main coronary artery
Answer: C. Right coronary artery
An inferior myocardial infarction with hypotension, elevated
JVP, and clear lungs suggests right ventricular infarction, most
commonly caused by right coronary artery occlusion. The
right ventricle is preload dependent, so aggressive nitrate
administration can worsen hypotension.
2.
,A 27-year-old woman develops sudden pleuritic chest pain
and dyspnea 5 days after undergoing knee surgery. She is
tachycardic and mildly hypoxemic. CT pulmonary angiography
demonstrates a filling defect in a segmental pulmonary
artery. Which finding would most likely be present on ECG?
A. ST-segment elevation in leads V1–V4
B. S1Q3T3 pattern
C. Prolonged PR interval
D. Diffuse ST-segment depression
Answer: B. S1Q3T3 pattern
Acute pulmonary embolism can produce right ventricular
strain, classically reflected by an S1Q3T3 pattern, although
sinus tachycardia is more common. The clinical setting of
recent surgery and acute pleuritic symptoms strongly
supports venous thromboembolism.
3.
A 58-year-old man with hypertension has progressive
exertional dyspnea and orthopnea. Echocardiography reveals
an ejection fraction of 30%. Which medication class improves
survival in patients with chronic systolic heart failure?
A. Loop diuretics
B. ACE inhibitors
C. Digoxin
D. Nitrates alone
Answer: B. ACE inhibitors
,ACE inhibitors reduce afterload, limit adverse ventricular
remodeling, and decrease mortality in heart failure with
reduced ejection fraction. Loop diuretics primarily provide
symptomatic relief without a demonstrated mortality benefit.
4.
A 72-year-old woman presents with palpitations and
dizziness. ECG demonstrates an irregularly irregular rhythm
with no discernible P waves. Which complication is she at
greatest risk of developing?
A. Ventricular septal rupture
B. Ischemic stroke
C. Complete heart block
D. Infective endocarditis
Answer: B. Ischemic stroke
Atrial fibrillation promotes blood stasis in the left atrial
appendage, increasing the risk of thromboembolic stroke.
Stroke prevention is determined by the patient's
thromboembolic risk and may require anticoagulation.
5.
A 35-year-old man presents with fever, weight loss, night
sweats, and a new murmur. He has a history of injection drug
use. Blood cultures grow Staphylococcus aureus. Which
cardiac valve is most likely affected?
, A. Aortic
B. Mitral
C. Tricuspid
D. Pulmonic
Answer: C. Tricuspid
Injection drug use is strongly associated with right-sided
infective endocarditis, particularly involving the tricuspid
valve. S. aureus is the most common causative organism.
6.
A 69-year-old man with a 50-pack-year smoking history
presents with chronic cough and progressive dyspnea.
Pulmonary function testing shows a reduced FEV1/FVC ratio
and increased total lung capacity. Which diagnosis is most
likely?
A. Pulmonary fibrosis
B. Emphysema
C. Restrictive chest wall disease
D. Sarcoidosis
Answer: B. Emphysema
Emphysema causes obstructive physiology with reduced
FEV1/FVC and hyperinflation. Destruction of alveolar walls
decreases elastic recoil and increases lung compliance.
7.
