USMLE Step 2 Quiz: Acute Coronary Syndromes

What this quiz covers

This quiz focuses on Acute Coronary Syndromes, giving you a quick way to practice the rules, question types, and explanations that matter most for USMLE Step 2.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. Unstable angina due to transient thrombosis with normal cardiac biomarkers and no myocardial necrosis.
2. Acute pericarditis due to pleuritic pain with diffuse ST elevations and PR depressions on ECG.
3. NSTEMI due to subendocardial ischemia with elevated troponin and no persistent ST elevation on ECG. (correct answer)
4. STEMI due to complete coronary occlusion with ST elevation in contiguous leads and reciprocal changes.
5. Stable angina due to fixed coronary stenosis causing exertional pain relieved by rest within minutes.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI. The correct answer is C, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, D, fails because it overlooks the absence of ST elevation and elevated troponin, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as ST depressions and troponin elevation. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of ECG findings.

Question 2

1. Unstable angina with ischemic ECG changes and negative biomarkers indicating no myocardial necrosis. (correct answer)
2. NSTEMI because any ST depression automatically implies myocardial infarction regardless of troponin results.
3. STEMI because lateral ischemia typically presents with ST depression rather than ST elevation.
4. Stable angina because symptoms resolved and therefore cannot represent an acute coronary syndrome.
5. GERD because transient chest pain relieved spontaneously is most consistent with esophageal reflux disease.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of unstable angina. The correct answer is A, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, B, fails because it overlooks that troponin is negative, distinguishing from NSTEMI, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as resolved pain and ST depression. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of ECG findings.

Question 3

1. Administer IV beta-blocker immediately to reduce myocardial oxygen demand despite bradycardia and hypotension.
2. Give atropine and supportive care for symptomatic bradycardia while continuing ACS therapy and urgent evaluation. (correct answer)
3. Discontinue antiplatelet therapy because bradycardia indicates noncardiac chest pain and low ACS risk.
4. Order outpatient Holter monitoring only because arrhythmia evaluation precedes any ACS management decisions.
5. Administer thrombolysis because bradycardia signifies an occlusive MI requiring fibrinolysis regardless of ECG findings.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI with bradycardia. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks contraindication of beta-blockers in bradycardia and hypotension, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as low heart rate and ST depressions. Apply guideline-directed management, and avoid common pitfalls such as inappropriate antianginal use.

Question 4

1. Begin high-dose ibuprofen for pain control because it reduces inflammation and improves infarct healing.
2. Start dual antiplatelet therapy with a P2Y12 inhibitor and initiate anticoagulation while preparing for PCI. (correct answer)
3. Give prophylactic antibiotics because bacteremia is common during PCI and worsens myocardial injury.
4. Administer thrombolytics routinely before PCI because combined therapy is always superior to PCI alone.
5. Delay antithrombotic therapy until after coronary angiography confirms a culprit lesion requiring intervention.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of STEMI. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the anti-inflammatory effects not being beneficial in ACS, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as anterior ST elevation. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of adjunct therapies.

Question 5

1. Discharge with sublingual nitroglycerin because symptom relief indicates low risk and troponin elevation is nonspecific.
2. Admit, start antithrombotic therapy, and risk-stratify for early invasive coronary angiography due to NSTEMI. (correct answer)
3. Administer fibrinolysis because elevated troponin confirms MI and thrombolysis is indicated for all MI types.
4. Treat with NSAIDs and observe because pain relief with nitroglycerin excludes acute coronary syndrome.
5. Order outpatient stress test only because absence of ST elevation indicates stable angina rather than ACS.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the elevated troponin requiring admission, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as pain relief with nitroglycerin but positive biomarkers. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of symptom resolution.

Question 6

1. Administer high-flow oxygen routinely because it reduces infarct size in all patients with acute coronary syndrome.
2. Withhold supplemental oxygen because routine oxygen is not indicated when saturation is adequate and patient is stable. (correct answer)
3. Intubate early for airway protection because all STEMI patients require mechanical ventilation before PCI.
4. Administer oxygen only after troponin results return because oxygen is contraindicated in NSTEMI.
5. Administer oxygen and delay PCI until saturation reaches 100% to minimize myocardial oxygen extraction.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of STEMI. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks evidence that routine oxygen may harm when SpO2 is normal, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as adequate saturation. Apply guideline-directed management, and avoid common pitfalls such as overuse of supplemental oxygen.

Question 7

1. Start aspirin and anticoagulation, add antianginal therapy, and admit for monitoring and further ischemic evaluation. (correct answer)
2. Provide reassurance and discharge because normal troponin excludes acute coronary syndrome and admission is unnecessary.
3. Administer thrombolytics because unstable angina is an early STEMI and requires immediate fibrinolysis.
4. Treat with ibuprofen and schedule outpatient endoscopy because episodic pain suggests reflux disease.
5. Order exercise stress testing immediately during active symptoms to confirm ischemia before any medications.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of unstable angina. The correct answer is A, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, B, fails because it overlooks the risk despite normal troponin, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as recurrent rest pain. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of negative biomarkers.

Question 8

1. Start IV nitroglycerin titration aggressively to reduce preload despite hypotension and suspected cardiogenic shock.
2. Give IV fluids bolus and high-dose beta-blocker immediately to reduce myocardial oxygen demand.
3. Activate emergent PCI and start vasopressor/inotrope support as needed for cardiogenic shock physiology. (correct answer)
4. Discharge with outpatient cardiology follow-up because rales and S3 are common in anxiety-related chest pain.
5. Administer NSAIDs for chest pain and delay reperfusion until blood pressure stabilizes spontaneously.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of STEMI with cardiogenic shock. The correct answer is C, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the contraindication of nitrates in hypotension, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as rales, S3, and ST elevation. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of shock physiology.

Question 9

1. Continue heparin because thrombocytopenia is expected in ACS and does not affect anticoagulation choice.
2. Stop heparin and start a non-heparin anticoagulant due to suspected HIT in the setting of platelet fall. (correct answer)
3. Stop aspirin because thrombocytopenia indicates aspirin-induced platelet destruction and requires immediate cessation.
4. Administer thrombolytics because thrombocytopenia suggests coronary thrombosis requiring fibrinolytic therapy urgently.
5. Give platelet transfusion routinely and continue heparin because transfusion prevents thrombosis in ACS patients.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI with suspected HIT. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the risk of thrombosis in HIT, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as platelet drop on heparin. Apply guideline-directed management, and avoid common pitfalls such as continuing implicated anticoagulants.

Question 10

1. NSTEMI characterized by ischemic ECG changes and elevated cardiac biomarkers without persistent ST elevation. (correct answer)
2. Unstable angina characterized by normal biomarkers and transient symptoms without evidence of myocardial necrosis.
3. STEMI characterized by ST elevation in contiguous leads and immediate need for reperfusion therapy.
4. Stable angina characterized by exertional chest pain relieved by rest and no biomarker elevation.
5. Costochondritis characterized by reproducible chest wall tenderness and normal ECG and cardiac biomarkers.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI. The correct answer is A, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, B, fails because it overlooks the elevated troponin indicating necrosis, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as T-wave inversions and elevated troponin. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of ECG findings.

Question 11

1. Start dual antiplatelet therapy and anticoagulation, give high-intensity statin, and admit for early invasive evaluation. (correct answer)
2. Discharge with proton pump inhibitor and arrange outpatient cardiology follow-up because symptoms are atypical for ACS.
3. Administer thrombolytics immediately because T-wave inversions indicate an occlusive STEMI equivalent in all patients.
4. Treat with NSAIDs and reassurance because normal blood pressure and no chest pain make ischemia unlikely.
5. Order exercise treadmill testing now to confirm ischemia before initiating antiplatelet or anticoagulant therapy.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI. The correct answer is A, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, B, fails because it overlooks the atypical presentation in women and diabetics, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as T-wave inversions and elevated troponin. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of ECG findings.

Question 12

1. Administer aspirin, start heparin infusion, and schedule outpatient stress testing within 72 hours if pain resolves.
2. Give aspirin and a P2Y12 inhibitor, activate emergent PCI, and administer anticoagulation while preparing for cath lab. (correct answer)
3. Order D-dimer and CT pulmonary angiography now because diaphoresis suggests pulmonary embolism more than ACS.
4. Provide ibuprofen for analgesia and observe on telemetry while awaiting serial troponins and repeat ECG.
5. Administer IV thrombolysis routinely for all suspected ACS before confirming STEMI on ECG to save time.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of STEMI. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the need for emergent reperfusion in STEMI, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as ST elevation. Apply guideline-directed management, and avoid common pitfalls such as delaying PCI.

Question 13

1. Continue aspirin and add ibuprofen because bronchospasm is mild and NSAIDs improve platelet inhibition.
2. Stop aspirin and use an alternative antiplatelet strategy such as a P2Y12 inhibitor, given aspirin hypersensitivity. (correct answer)
3. Administer thrombolytics because antiplatelet therapy cannot be used when aspirin intolerance is suspected.
4. Discontinue heparin because aspirin reaction indicates bleeding risk and anticoagulation is contraindicated.
5. Discharge home because bronchospasm suggests asthma exacerbation rather than acute coronary syndrome.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI with aspirin hypersensitivity. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks the risk of aspirin-induced bronchospasm, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as wheezing post-aspirin. Apply guideline-directed management, and avoid common pitfalls such as ignoring drug allergies.

Question 14

1. Continue medical therapy only and plan outpatient stress testing because no ST elevation is present.
2. Proceed with early invasive strategy including coronary angiography due to refractory ischemia and high-risk features. (correct answer)
3. Administer fibrinolysis because refractory symptoms in NSTEMI indicate an occlusive thrombus requiring thrombolytics.
4. Stop antithrombotics and treat with NSAIDs because persistent pain suggests musculoskeletal chest wall strain.
5. Order D-dimer and lower-extremity ultrasound because dynamic ST changes are typical for pulmonary embolism.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of NSTEMI with refractory symptoms. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks high-risk features requiring invasive strategy, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as persistent pain and dynamic ST changes. Apply guideline-directed management, and avoid common pitfalls such as misinterpretation of refractory ischemia.

Question 15

1. Continue warfarin at current dose and add full-dose heparin because triple anticoagulation is routinely recommended.
2. Assess bleeding risk and coordinate antithrombotic strategy, avoiding unnecessary overlapping anticoagulation given supratherapeutic INR. (correct answer)
3. Stop aspirin because antiplatelet therapy is contraindicated in all patients receiving chronic anticoagulation.
4. Administer thrombolytics because unstable angina requires immediate reperfusion when INR is elevated.
5. Order outpatient coronary calcium scoring because it guides therapy better than inpatient monitoring in unstable angina.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of unstable angina with anticoagulation overlap. The correct answer is B, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, A, fails because it overlooks bleeding risk with supratherapeutic INR, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as elevated INR. Apply guideline-directed management, and avoid common pitfalls such as ignoring anticoagulation status.

Question 16

1. Activate PCI team and give antiplatelet therapy and anticoagulation promptly while preparing for emergent reperfusion. (correct answer)
2. Order serial troponins before activating PCI because biomarkers must confirm MI prior to catheterization.
3. Administer thrombolytics immediately because they are preferred over PCI when symptoms are under 2 hours.
4. Treat with NSAIDs and observe because ST elevations can occur with benign early repolarization in older adults.
5. Schedule outpatient stress test after discharge because ST elevation does not require emergent intervention.

Explanation: This question tests understanding and management of Acute Coronary Syndromes as per USMLE Step 2 CK standards. Acute Coronary Syndromes encompass conditions like STEMI, NSTEMI, and Unstable Angina, characterized by acute myocardial ischemia. In this scenario, the patient's symptoms and ECG findings are indicative of STEMI. The correct answer is A, which aligns with current management guidelines and addresses the patient's immediate needs. A common distractor, B, fails because it overlooks that ECG is sufficient for activation in STEMI, leading to inadequate management. To approach similar questions, identify key symptoms and diagnostic markers such as ST elevation. Apply guideline-directed management, and avoid common pitfalls such as delaying reperfusion.

Question 17

1. Stable angina
2. Unstable angina (correct answer)
3. Non-ST-elevation myocardial infarction
4. Prinzmetal angina

Explanation: This patient's symptoms have changed from a stable pattern to one of increasing frequency and severity, now occurring at rest. This crescendo pattern and rest angina are hallmarks of unstable angina. Stable angina is characterized by predictable, exertional chest pain that is consistent over time. Non-ST-elevation myocardial infarction (NSTEMI) is excluded by the undetectable troponin level, which indicates no myocardial necrosis. Prinzmetal angina is caused by coronary vasospasm and typically occurs at rest, often during the night, but is less likely given the patient's preceding history of exertional symptoms.

Question 18

1. Left anterior descending artery
2. Left circumflex artery
3. Right coronary artery (correct answer)
4. Obtuse marginal branch

Explanation: ST-segment elevation in the inferior leads (II, III, and aVF) localizes the myocardial infarction to the inferior wall of the left ventricle. The right coronary artery (RCA) is the vessel that supplies the inferior wall in approximately 85% of individuals. The associated bradycardia and hypotension are also characteristic of an RCA occlusion, as this artery typically supplies the sinoatrial (SA) and atrioventricular (AV) nodes.

Question 19

1. Major surgery 4 weeks ago
2. Ischemic stroke 1 year ago
3. Prior intracranial hemorrhage at any time (correct answer)
4. Blood pressure of 190/110 mm Hg on presentation

Explanation: A history of any prior intracranial hemorrhage (ICH) is an absolute contraindication to fibrinolytic therapy due to the high risk of recurrent bleeding. Major surgery within the past 3 weeks is a relative contraindication. An ischemic stroke more than 3 months ago is a relative, not absolute, contraindication. Severe uncontrolled hypertension (systolic >180 mm Hg or diastolic >110 mm Hg) is a contraindication, but it can often be treated with antihypertensives to allow for fibrinolysis, making it a relative contraindication that can be mitigated.

Question 20

1. Discharge home with follow-up stress test in 1 week
2. Admit for observation and serial troponins only
3. Proceed with coronary angiography within 24 hours (correct answer)
4. Schedule for elective coronary artery bypass grafting

Explanation: This patient has an NSTEMI with multiple high-risk features (diabetes, prior MI, ST depressions, positive biomarkers), which gives him a high TIMI or GRACE risk score. Current guidelines recommend an early invasive strategy, defined as coronary angiography within 24 hours, for high-risk NSTEMI patients to identify and treat the culprit lesion. A conservative strategy or outpatient testing is inappropriate for a high-risk patient. CABG may be indicated eventually, but angiography is the necessary diagnostic step first.