Acute Coronary Syndrome Medications Practice Questions

73 multiple-choice questions on Acute coronary syndrome for paramedic and EMT students, from Chapter 15 (Emergency Medications). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

73 practice questions

1. A patient with suspected ACS takes apixaban for atrial fibrillation and has no signs of bleeding. Regarding aspirin, most protocols direct you to:

   1. A. Withhold it; apixaban already covers it
   2. B. Give 81 mg to reduce the bleeding risk
   3. C. Give it after a hospital INR check
   4. D. Give 162 to 325 mg chewed as usual
   Show answer

   Answer: D. Give 162 to 325 mg chewed as usual

   Anticoagulants such as apixaban act on clotting factors, not platelets, and do not replace aspirin's antiplatelet effect in ACS; without active bleeding or true allergy the usual chewed dose is given and the anticoagulant is reported. A reduced 81-mg dose gives an incomplete loading effect. INR does not measure apixaban's effect, and waiting delays a drug that lowers mortality.

2. A patient with suspected ACS has mild asthma and takes ibuprofen regularly without problems. Regarding aspirin:

   1. A. Give it rectally to avoid wheezing
   2. B. Give 81 mg with an albuterol nebulizer
   3. C. Give the usual chewed dose
   4. D. Withhold it because of the asthma
   Show answer

   Answer: C. Give the usual chewed dose

   Asthma alone is not a contraindication; only patients who have had bronchospasm after aspirin or other NSAIDs (aspirin-exacerbated respiratory disease) should not receive it, and this patient tolerates ibuprofen. A rectal route does not prevent a true sensitivity reaction. A reduced dose with a nebulizer is not needed and gives incomplete platelet inhibition.

3. A patient with an inferior STEMI has a normal right-sided ECG (no ST elevation in V4R), a BP of 148/88, and ongoing pain. Regarding nitroglycerin:

   1. A. Give it after a 1-L fluid bolus is complete
   2. B. Give a double dose for the inferior wall
   3. C. Avoid it because the STEMI is inferior
   4. D. Give it cautiously with an IV in place
   Show answer

   Answer: D. Give it cautiously with an IV in place

   Inferior STEMI is not itself a contraindication; the danger is right ventricular involvement or hypotension. With no RV infarct, a good BP, and an IV established in case of hypotension, sublingual nitroglycerin can be given and the BP rechecked before each dose. A routine liter of fluid is not needed, and doubling the dose raises the risk of hypotension.

4. A STEMI patient is 10 minutes from a hospital without a cath lab and 35 minutes from a PCI center. First medical contact to device can be met within 90 minutes. Where should you transport?

   1. A. Whichever hospital the family prefers
   2. B. The closer hospital for fibrinolytics
   3. C. The closer hospital, then a transfer by air
   4. D. The PCI center, bypassing the closer one
   Show answer

   Answer: D. The PCI center, bypassing the closer one

   When primary PCI can be done within 90 minutes of first medical contact, direct transport to a PCI-capable center is preferred, even if that means bypassing a closer hospital; it gives better outcomes than fibrinolysis. Stopping at the closer hospital adds a door-in-door-out delay. Family preference does not override a time-critical STEMI destination decision.

5. Caution with nitroglycerin is warranted in suspected right ventricular infarction because:

   1. A. It causes profound bradycardia in RV infarction
   2. B. It worsens chest pain by causing coronary steal
   3. C. It sharply increases heart rate and oxygen demand
   4. D. RV infarct patients are preload dependent
   Show answer

   Answer: D. RV infarct patients are preload dependent

   Nitroglycerin is a venodilator that reduces preload, and patients with right ventricular infarction depend on preload to fill the left heart, so they may become severely hypotensive; a right-sided ECG (V4R) helps identify them. Nitroglycerin does not cause profound bradycardia (RV infarction itself may), it does not cause coronary steal in ACS, and its reflex tachycardia is modest rather than a sharp rise in oxygen demand.

6. Morphine in acute coronary syndrome is used to:

   1. A. Dissolve the coronary clot and restore flow
   2. B. Relieve pain and anxiety and reduce preload
   3. C. Reduce bleeding risk from antiplatelet agents
   4. D. Increase the heart rate and cardiac output
   Show answer

   Answer: B. Relieve pain and anxiety and reduce preload

   Monitor for hypotension and respiratory depression. It is used when nitrates are inadequate.

7. Fentanyl is often chosen over morphine for analgesia because it:

   1. A. Lasts longer than morphine, needing fewer doses
   2. B. Causes no respiratory depression at usual doses
   3. C. Is not a controlled substance in most states
   4. D. Has rapid onset with less histamine release
   Show answer

   Answer: D. Has rapid onset with less histamine release

   It is dosed in micrograms, which makes dosing errors dangerous. It also causes less hypotension.

8. A 12-lead ECG in suspected ACS should be obtained:

   1. A. Only if chest pain persists after nitro
   2. B. After arrival at the receiving hospital
   3. C. After all medications have been given
   4. D. Within 10 minutes of patient contact
   Show answer

   Answer: D. Within 10 minutes of patient contact

   Early transmission activates the catheterization team sooner.

9. The main goal in ST-elevation myocardial infarction is:

   1. A. Rapid reperfusion by PCI or fibrinolytics
   2. B. Strict blood pressure control below 120
   3. C. Complete pain relief before any transport
   4. D. Rhythm control with prophylactic lidocaine
   Show answer

   Answer: A. Rapid reperfusion by PCI or fibrinolytics

   Transport destination is the key EMS decision.

10. A fibrinolytic checklist is used to:

    1. A. Calculate the transport time to the PCI center
    2. B. Confirm the STEMI diagnosis from the 12-lead ECG
    3. C. Determine the weight-based fibrinolytic dose
    4. D. Screen for bleeding and stroke contraindications
    Show answer

    Answer: D. Screen for bleeding and stroke contraindications

    It matters where PCI is not available quickly. Contraindications include recent surgery, bleeding, or stroke.

11. Heparin given in ACS acts to:

    1. A. Lower the blood pressure
    2. B. Relieve ischemic chest pain
    3. C. Prevent clot propagation
    4. D. Dissolve the existing clot
    Show answer

    Answer: C. Prevent clot propagation

    Its use in the field depends on local protocol.

12. Oxygen in acute coronary syndrome should be:

    1. A. Given only during transport, never on scene
    2. B. Withheld entirely, even when the patient is hypoxic
    3. C. Titrated to normal saturation; hyperoxia may harm
    4. D. Given to every patient at 15 L/min by mask
    Show answer

    Answer: C. Titrated to normal saturation; hyperoxia may harm

    Routine high-flow oxygen is no longer recommended for all ACS patients.

13. Your STEMI protocol for patients receiving fibrinolytics calls for unfractionated heparin 60 units/kg IV, maximum 4,000 units. What bolus does an 80-kg patient receive?

    1. A. 4,000 units IV
    2. B. 8,000 units IV
    3. C. 4,800 units IV
    4. D. 480 units IV
    Show answer

    Answer: A. 4,000 units IV

    60 units/kg x 80 kg = 4,800 units, which exceeds the 4,000-unit cap, so the patient receives 4,000 units. Giving the full 4,800 units ignores the maximum and raises bleeding risk with a fibrinolytic. 480 units is a tenfold error. 8,000 units uses 100 units/kg and ignores the cap.

14. Medical control orders a ticagrelor loading dose for a STEMI patient going to a PCI center. What dose is given?

    1. A. 180 mg orally
    2. B. 600 mg orally
    3. C. 18 mg orally
    4. D. 90 mg orally
    Show answer

    Answer: A. 180 mg orally

    The ticagrelor loading dose is 180 mg by mouth, followed later by 90 mg twice daily. 90 mg is the maintenance dose. 600 mg is the clopidogrel loading dose before PCI. 18 mg is a tenfold error.

15. Twenty minutes after a fibrinolytic, a STEMI patient has slow oozing from an IV site and no neurologic change. What is the most appropriate action?

    1. A. Give tranexamic acid IV for the oozing
    2. B. Pull that IV and start a new one elsewhere
    3. C. Divert to the closest hospital at once
    4. D. Apply direct pressure and keep monitoring
    Show answer

    Answer: D. Apply direct pressure and keep monitoring

    Minor oozing at puncture sites is common after fibrinolysis; firm direct pressure, avoiding new punctures and IM injections, and close monitoring for major bleeding or neurologic change are appropriate. Pulling the IV and puncturing a new site adds another bleeding point, minor oozing alone does not call for tranexamic acid or a diversion, and it still needs watching because it can herald serious bleeding.

16. Aspirin should be given to a suspected ACS patient:

    1. A. Only after the 12-lead confirms STEMI
    2. B. Only after arrival at the hospital
    3. C. Only after nitroglycerin has relieved pain
    4. D. Early, regardless of 12-lead findings
    Show answer

    Answer: D. Early, regardless of 12-lead findings

    Early aspirin benefits all ACS presentations. Give it as early as possible if there is no contraindication.

17. A patient's chest pain began 20 hours ago, and the ECG shows STEMI. The nearest PCI center is 2.5 hours away. Regarding routine fibrinolysis:

    1. A. Give half the usual dose to lower risk
    2. B. Give it; timing does not matter
    3. C. Give it after a heparin bolus first
    4. D. It is generally not given now
    Show answer

    Answer: D. It is generally not given now

    Fibrinolysis benefits STEMI patients most when given early and is generally indicated within 12 hours of symptom onset; beyond that, routine fibrinolysis is not recommended and transfer for PCI is preferred (especially with ongoing ischemia or shock). Timing matters greatly. Halving the dose is not an accepted way to extend the window, and a heparin bolus does not make late lysis beneficial.

18. A STEMI patient is 2.5 hours from a PCI center. The fibrinolytic checklist shows an ischemic stroke 6 weeks ago. This finding is:

    1. A. Relevant in patients over 75
    2. B. An absolute contraindication
    3. C. Not relevant after 30 days
    4. D. A relative contraindication
    Show answer

    Answer: B. An absolute contraindication

    Ischemic stroke within the past 3 months is an absolute contraindication to fibrinolysis (except acute stroke within 4.5 hours), because of the high risk of hemorrhagic conversion. It is not merely relative, it does not depend on age, and 6 weeks is well inside the 3-month window.

19. A STEMI patient being screened for fibrinolysis has a BP of 196/118 on arrival. On the checklist, this is:

    1. A. Not relevant to the decision
    2. B. A relative contraindication
    3. C. A reason to give a double dose
    4. D. An absolute contraindication
    Show answer

    Answer: B. A relative contraindication

    Severe uncontrolled hypertension on presentation (SBP above 180 or DBP above 110 mm Hg) is a relative contraindication because it raises the risk of intracranial hemorrhage; the physician weighs it and may lower the BP first. It is not on the absolute list. It is relevant to the decision, and hypertension never calls for a larger fibrinolytic dose.

20. A patient with suspected ACS is vomiting repeatedly and cannot safely chew or swallow. Per many protocols, which aspirin option may be used?

    1. A. A rectal aspirin suppository
    2. B. An IM injection of aspirin
    3. C. Aspirin dissolved and given IV
    4. D. Withhold aspirin until the hospital
    Show answer

    Answer: A. A rectal aspirin suppository

    When a patient with suspected ACS cannot take oral aspirin because of vomiting, an aspirin suppository (commonly 300 to 600 mg) is a safe alternative where carried. Simply withholding loses the early antiplatelet benefit. Aspirin is not given IM, and oral aspirin tablets must never be dissolved and given IV.

21. Sixty to 90 minutes after a fibrinolytic is given for STEMI, which finding best suggests successful reperfusion?

    1. A. ST elevation falls by at least half
    2. B. Rising chest pain with nausea
    3. C. New ST depression in the inferior leads
    4. D. A new left bundle branch block
    Show answer

    Answer: A. ST elevation falls by at least half

    Markers of successful reperfusion include resolution of ST elevation by 50% or more at 60 to 90 minutes, relief of pain, and reperfusion rhythms such as accelerated idioventricular rhythm. New ST depression, a new bundle branch block, and worsening pain suggest continued ischemia and possible failed fibrinolysis, which calls for rescue PCI.

22. IV nitroglycerin infusion for ACS is started at:

    1. A. 100 mcg/min, then tapered as pain resolves
    2. B. 5–10 mcg/min, titrated every 3–5 minutes
    3. C. 50 mcg/min, titrated every 30 to 60 minutes
    4. D. 1 mg/min, titrated every 3–5 minutes
    Show answer

    Answer: B. 5–10 mcg/min, titrated every 3–5 minutes

    Start at 5 to 10 mcg/min and increase by 5 to 10 mcg/min every 3 to 5 minutes to pain relief while the SBP stays at or above 90 mm Hg (and does not fall 30 mm Hg or more below baseline). Starting at 100 mcg/min risks sudden hypotension. Titrating every 30 to 60 minutes is far too slow for a drug with a minutes-long half-life. 1 mg/min is about 100 times the starting dose.

23. During an interfacility transfer, a STEMI patient on an eptifibatide infusion develops brisk bleeding from the gums and IV site. What is the first action?

    1. A. Halve the rate and keep it running
    2. B. Give TXA and continue the drip
    3. C. Stop the infusion; apply pressure
    4. D. Keep it running; apply pressure
    Show answer

    Answer: C. Stop the infusion; apply pressure

    Eptifibatide is a glycoprotein IIb/IIIa platelet inhibitor; significant bleeding calls for stopping the infusion, applying direct pressure, and contacting the receiving physician. Halving the rate or keeping it running with pressure or TXA still delivers the platelet inhibitor while the bleeding is brisk.

24. A patient with ongoing ischemic chest pain has a BP of 194/110 and no signs of RV infarction or PDE-5 inhibitor use. Which drug both treats the ischemia and lowers the BP?

    1. A. Furosemide 40 mg IV
    2. B. Labetalol alone, no nitrate
    3. C. Hydralazine 20 mg IM
    4. D. Nitroglycerin, titrated
    Show answer

    Answer: D. Nitroglycerin, titrated

    Nitroglycerin relieves ischemic pain and lowers BP by reducing preload and afterload, so it is the usual first drug in hypertensive ACS, titrated (IV in many systems) to pain and BP. Furosemide is for volume overload. Labetalol may be added in some hospitals but does not replace nitrates for ischemia, and it is avoided with heart failure or cocaine use. Hydralazine causes reflex tachycardia, which raises myocardial oxygen demand.

25. A patient with suspected ACS had a bleeding stomach ulcer 5 years ago that was treated, and has had no bleeding since. Regarding aspirin:

    1. A. Give 81 mg to protect the stomach
    2. B. Give the usual chewed dose
    3. C. Give it with an antacid first
    4. D. Withhold it because of the history
    Show answer

    Answer: B. Give the usual chewed dose

    A remote, treated GI bleed is not a contraindication; active or recent significant bleeding is. The usual chewed dose is given and the history is reported. A reduced dose gives incomplete platelet inhibition, and an antacid is not needed before a single loading dose.

26. A patient says his nitroglycerin tablets 'don't burn under my tongue anymore,' so they must be bad. What is accurate?

    1. A. Lack of burning is not a reliable test
    2. B. He should swallow the tablets instead
    3. C. Burning means the dose is too high
    4. D. Burning proves that the tablets are potent
    Show answer

    Answer: A. Lack of burning is not a reliable test

    Current sublingual nitroglycerin tablets often cause no tingling or burning, so the sensation is not a reliable test of potency; check the expiration date and whether the tablets were stored tightly closed in the original glass bottle, and use your own supply if in doubt. Burning does not prove potency or signal an excessive dose, and swallowed nitroglycerin is largely broken down by the liver, so it does not replace the sublingual route.

27. Two minutes after a sublingual nitroglycerin, a patient becomes pale and diaphoretic with a heart rate of 44 and a BP of 76/40. What is the most appropriate response?

    1. A. Give metoprolol 5 mg IV
    2. B. Lay flat, raise legs, give fluid
    3. C. Sit the patient upright and recheck
    4. D. Give a second nitroglycerin tablet now
    Show answer

    Answer: B. Lay flat, raise legs, give fluid

    Nitroglycerin can trigger a vasovagal (Bezold-Jarisch) reaction with paradoxical bradycardia and hypotension. Lay the patient flat with the legs raised and give fluids; atropine is used if the bradycardia persists. Another nitroglycerin and a beta blocker would worsen both problems. Sitting upright lowers venous return further.

28. Clopidogrel/ticagrelor (P2Y12 inhibitors) in ACS are:

    1. A. Given routinely by all paramedics to every ACS patient
    2. B. Given prehospital in some STEMI systems per protocol
    3. C. Classified as fibrinolytics that dissolve the clot
    4. D. Contraindicated in all patients receiving aspirin
    Show answer

    Answer: B. Given prehospital in some STEMI systems per protocol

    P2Y12 inhibitors are a loading dose adjunct in STEMI pathways. Prehospital use typically follows physician consultation.

29. You are transferring a patient on a nitroglycerin infusion. Why does the label call for non-PVC (polyvinyl chloride) tubing?

    1. A. Non-PVC tubing allows faster rates
    2. B. Nitroglycerin cracks PVC tubing
    3. C. PVC tubing absorbs the drug
    4. D. PVC tubing makes the drug toxic
    Show answer

    Answer: C. PVC tubing absorbs the drug

    Nitroglycerin is absorbed into standard PVC tubing, so less drug reaches the patient and the dose becomes unpredictable; the label calls for non-PVC sets (and glass bottles when not premixed). PVC does not make it toxic, non-PVC tubing does not change the possible rate, and the drug does not damage the tubing.

30. Fibrinolytics (e.g., tenecteplase) are indicated in STEMI when:

    1. A. PCI is delayed and no contraindications exist
    2. B. Symptoms started over 24 hours ago and pain persists
    3. C. Any chest pain with risk factors, before a 12-lead
    4. D. The patient is hypotensive and in cardiogenic shock
    Show answer

    Answer: A. PCI is delayed and no contraindications exist

    Fibrinolysis is time-sensitive, ideally within 30 minutes of arrival if PCI unavailable. PCI must be unavailable within the recommended window.

31. Absolute contraindications to fibrinolysis include:

    1. A. Prior ICH, active bleeding, or aortic dissection
    2. B. Type 2 diabetes with mild diabetic retinopathy
    3. C. Controlled hypertension on two daily medications
    4. D. Age over 65 years with a history of stable angina
    Show answer

    Answer: A. Prior ICH, active bleeding, or aortic dissection

    Bleeding risk, especially intracranial, drives contraindications. Prior intracranial hemorrhage (ICH), ischemic stroke within 3 months, active bleeding, and suspected aortic dissection are all absolute contraindications.

32. Beta blockers in ACS:

    1. A. Replace aspirin as the first antiplatelet drug
    2. B. Are absolutely contraindicated in every ACS patient
    3. C. Are given IV to every ACS patient before arrival
    4. D. Are usually given orally in hospital within 24 hours
    Show answer

    Answer: D. Are usually given orally in hospital within 24 hours

    Early IV beta blockade in shock-risk patients increases mortality. IV use is reserved for hypertension or tachycardia without heart failure or shock.

33. Which finding contraindicates beta blockers in ACS?

    1. A. Heart failure, hypotension, or cocaine use
    2. B. Sinus tachycardia at 110/min with normal BP
    3. C. Anxiety and restlessness during transport
    4. D. Hypertension with a systolic above 160 mm Hg
    Show answer

    Answer: A. Heart failure, hypotension, or cocaine use

    Cocaine-associated ACS is treated with benzodiazepines and nitrates; beta blockers cause unopposed alpha effects. Bradycardia is also a contraindication.

34. A STEMI patient who received a ticagrelor loading dose reports mild shortness of breath. SpO2 is 97%, the lungs are clear, and the BP is stable. What is the most likely explanation?

    1. A. A known, usually mild side effect
    2. B. Opioid toxicity needing naloxone
    3. C. An allergic reaction needing epinephrine
    4. D. Pulmonary edema needing furosemide
    Show answer

    Answer: A. A known, usually mild side effect

    Dyspnea is a recognized side effect of ticagrelor (about 1 in 7 patients in its main trial), usually mild and self-limited; with clear lungs, normal SpO2, and stable vital signs, monitor and report it. There are no hives, wheezing, or hypotension to suggest anaphylaxis. Clear lungs argue against pulmonary edema. Ticagrelor is not an opioid.

35. The 'MONA' mnemonic is outdated because:

    1. A. Oxygen is not routine and morphine is used cautiously
    2. B. Nitroglycerin is now contraindicated in most ACS patients
    3. C. Aspirin is now held until a STEMI is confirmed on the 12-lead
    4. D. Oxygen should now go by nonrebreather
    Show answer

    Answer: A. Oxygen is not routine and morphine is used cautiously

    Modern care: aspirin early, nitrates, oxygen only if hypoxic, opioids cautiously. The order also matters, with aspirin given first. Nitroglycerin is still used when no contraindication exists, aspirin is given for any suspected ACS without waiting for a STEMI, and routine high-flow oxygen can harm a patient who is not hypoxic.

36. A patient with chest pain takes riociguat (Adempas) for pulmonary hypertension. Regarding nitroglycerin:

    1. A. Allowed as nitroglycerin paste instead
    2. B. Allowed at half the usual 0.4-mg dose
    3. C. Contraindicated, like with PDE-5 inhibitors
    4. D. Safe, because riociguat is not a PDE-5 drug
    Show answer

    Answer: C. Contraindicated, like with PDE-5 inhibitors

    Riociguat stimulates soluble guanylate cyclase, the same pathway nitrates use, and its label contraindicates nitrates because the combination causes severe hypotension. That it is not a PDE-5 inhibitor does not make it safe. Paste and reduced doses still deliver nitrate and carry the same risk.

37. Ondansetron may be given in ACS for:

    1. A. Hypotension after nitroglycerin is given
    2. B. Bradycardia that occurs with inferior MI
    3. C. Nausea, common with inferior MI and opioids
    4. D. Chest pain that persists after nitroglycerin
    Show answer

    Answer: C. Nausea, common with inferior MI and opioids

    Monitor QT, since ondansetron can prolong it.

38. ST-elevation in leads II, III, and aVF indicates:

    1. A. Lateral MI
    2. B. Inferior MI
    3. C. Posterior MI
    4. D. Anterior MI
    Show answer

    Answer: B. Inferior MI

    Inferior MI is often RCA occlusion; check for RV involvement.

39. A patient with an inferior STEMI and RV involvement has a BP of 84/50 and clear lungs. Which fluid approach is typical?

    1. A. D5W at a keep-open rate alone
    2. B. 250–500 mL NS boluses, reassessing
    3. C. No fluid; it will cause pulmonary edema
    4. D. 4 L of NS as fast as possible
    Show answer

    Answer: B. 250–500 mL NS boluses, reassessing

    Right ventricular infarction is preload-dependent, so modest isotonic boluses (commonly 250 to 500 mL) with reassessment of BP and lung sounds after each are used. Withholding fluid leaves the RV underfilled. Several liters at once can overdistend the failing RV and cause pulmonary edema. D5W at a keep-open rate gives no volume.

40. Aspirin given to a patient who already took 81 mg at home:

    1. A. Is dangerous because of the bleeding risk
    2. B. Should be supplemented to reach 162–325 mg
    3. C. Should be given as a full 650 mg dose on top
    4. D. Should be withheld, since 81 mg is enough
    Show answer

    Answer: B. Should be supplemented to reach 162–325 mg

    Ensure a full antiplatelet loading dose.

41. A patient has sudden tearing chest pain radiating to the back and a 30 mm Hg difference in arm BPs. Which ACS drugs should be withheld?

    1. A. Fentanyl and ondansetron
    2. B. Labetalol and esmolol
    3. C. Aspirin and heparin
    4. D. Oxygen and IV fluids
    Show answer

    Answer: C. Aspirin and heparin

    These findings suggest aortic dissection, where antiplatelets and anticoagulants can worsen bleeding into the aortic wall, so aspirin and heparin are withheld until it is excluded. Oxygen and IV access are still appropriate as indicated. Analgesia and antiemetics are given. Beta blockers such as esmolol or labetalol are used to lower heart rate and shear stress.

42. Target heart rate and BP in suspected aortic dissection are achieved with:

    1. A. Large fluid boluses to maintain organ perfusion
    2. B. An IV beta blocker first, then a vasodilator
    3. C. Nitroglycerin alone, before any rate control
    4. D. Aspirin and heparin to prevent clot extension
    Show answer

    Answer: B. An IV beta blocker first, then a vasodilator

    Reduce shear stress by lowering heart rate before BP. Esmolol or labetalol are typical choices.

43. A 58-year-old with an inferior STEMI has a BP of 88/50, clear lungs, and took sildenafil yesterday. Which plan is most appropriate?

    1. A. Nitroglycerin paste in place of tablets
    2. B. Morphine 4 mg IV to reduce cardiac preload
    3. C. Aspirin and a cautious fluid bolus; no nitrates
    4. D. Sublingual nitroglycerin 0.4 mg, repeated
    Show answer

    Answer: C. Aspirin and a cautious fluid bolus; no nitrates

    Hypotension, a likely RV infarct, and recent PDE-5 inhibitor use all contraindicate nitrates; preload support is needed instead.

44. A patient with chest pain has a BP of 146/90 and a heart rate of 88. He last took tadalafil three days ago. Regarding nitroglycerin:

    1. A. It may be given because more than 48 hours have passed
    2. B. It is contraindicated for 7 days after tadalafil
    3. C. Only nitroglycerin paste may be used safely
    4. D. The dose must be halved to 0.2 mg sublingual
    Show answer

    Answer: A. It may be given because more than 48 hours have passed

    Nitrates are avoided within 24 hours of sildenafil or vardenafil and 48 hours of tadalafil.

45. A patient with chest pain reports hives and wheezing after taking aspirin in the past. What is the best action?

    1. A. Give 81 mg of enteric-coated aspirin instead
    2. B. Withhold aspirin and notify the receiving facility
    3. C. Give aspirin after diphenhydramine pretreatment
    4. D. Give aspirin rectally to avoid the reaction
    Show answer

    Answer: B. Withhold aspirin and notify the receiving facility

    A true aspirin hypersensitivity is a contraindication; the hospital can use an alternative antiplatelet agent.

46. A patient with suspected ACS reports two days of black, tarry stools and lightheadedness. Regarding aspirin, the most appropriate action is:

    1. A. Withhold it because of suspected active GI bleeding
    2. B. Give 324 mg because the benefit always outweighs risk
    3. C. Give it only after a 1-L fluid bolus
    4. D. Give 81 mg as a reduced, safer dose
    Show answer

    Answer: A. Withhold it because of suspected active GI bleeding

    Active gastrointestinal bleeding is a contraindication to aspirin; consult medical control per protocol.

47. A patient with suspected ACS chewed 324 mg of aspirin 30 minutes before you arrived. What is appropriate?

    1. A. No additional aspirin is needed
    2. B. Give 81 mg to top up the earlier dose
    3. C. Give aspirin IV to ensure absorption
    4. D. Give another 324 mg as a loading dose
    Show answer

    Answer: A. No additional aspirin is needed

    A full non-enteric-coated dose taken recently provides the intended antiplatelet effect.

48. A patient with chest pain has a BP of 132/84 and sinus bradycardia at 42/min. Regarding nitroglycerin:

    1. A. Give half a tablet (0.2 mg) instead
    2. B. Withhold it due to the rate below 50
    3. C. Give 0.4 mg because the BP is adequate
    4. D. Give it as an IV drip at 10 mcg/min
    Show answer

    Answer: B. Withhold it due to the rate below 50

    Nitrates are avoided with marked bradycardia (under 50/min) because the patient may not compensate for vasodilation. A heart rate below 50 is a contraindication. A smaller tablet or an IV drip still causes vasodilation the bradycardic patient may not compensate for.

49. A chest pain patient's baseline BP of 160/90 falls to 124/70 after one nitroglycerin, and the pain persists. Per AHA guidance:

    1. A. Withhold further nitrates; SBP fell 30 mm Hg or more
    2. B. Switch to nitroglycerin paste at 2 inches
    3. C. Double the next dose to relieve the pain faster
    4. D. Give the next dose since SBP remains above 90
    Show answer

    Answer: A. Withhold further nitrates; SBP fell 30 mm Hg or more

    Nitrates are avoided when SBP is below 90 mm Hg or has dropped 30 mm Hg or more below baseline.

50. A patient with an inferior STEMI has ST elevation in V4R, a BP of 100/60, and clear lungs. Which is most appropriate?

    1. A. Start a nitroglycerin infusion at 10 mcg/min
    2. B. Give furosemide 40 mg IV to reduce preload
    3. C. Avoid nitrates and give fluid boluses if hypotensive
    4. D. Give nitroglycerin 0.4 mg every 5 minutes
    Show answer

    Answer: C. Avoid nitrates and give fluid boluses if hypotensive

    Right ventricular infarction is preload-dependent; nitrates and diuretics can cause profound hypotension.

51. After a sublingual nitroglycerin, a chest pain patient becomes lightheaded with a BP of 70/40. What is the best management?

    1. A. Sit the patient fully upright to aid breathing
    2. B. Give a second nitroglycerin to relieve the pain
    3. C. Give epinephrine 1 mg IV push to restore BP
    4. D. Place supine, raise the legs, and give a fluid bolus
    Show answer

    Answer: D. Place supine, raise the legs, and give a fluid bolus

    Nitrate-induced hypotension usually responds to supine positioning and volume; further nitrates are withheld.

52. A STEMI patient has an SpO2 of 97% on room air and no dyspnea. What oxygen therapy is appropriate?

    1. A. CPAP at 10 cm H2O to reduce preload
    2. B. Nasal cannula at 6 L/min routinely
    3. C. No supplemental oxygen is needed
    4. D. Nonrebreather mask at 15 L/min
    Show answer

    Answer: C. No supplemental oxygen is needed

    AHA guidance gives oxygen in ACS only for hypoxemia (SpO2 below 90%) or respiratory distress.

53. Why has routine morphine in ACS been de-emphasized?

    1. A. It is chemically incompatible with chewed aspirin
    2. B. It may worsen outcomes and delay antiplatelets
    3. C. It directly increases platelet aggregation in the coronary arteries
    4. D. It causes coronary vasospasm in most patients with STEMI
    Show answer

    Answer: B. It may worsen outcomes and delay antiplatelets

    Observational data link morphine to worse outcomes, and it delays the absorption and effect of oral P2Y12 inhibitors.

54. A 90-kg STEMI patient has ongoing pain after three nitroglycerin doses and a BP of 130/80. Per many protocols, which fentanyl dose is appropriate?

    1. A. 1 to 2 mcg IV as a total dose
    2. B. 50 to 100 mcg IV, titrated
    3. C. 900 mcg IV (10 mcg/kg)
    4. D. 500 mcg IV over 1 minute
    Show answer

    Answer: B. 50 to 100 mcg IV, titrated

    Fentanyl is commonly dosed about 1 mcg/kg IV (often 25 to 100 mcg) and titrated to pain and BP.

55. A 30-year-old has chest pain after using cocaine, with a heart rate of 128, a BP of 172/100, and agitation. Which drugs are first-line?

    1. A. Haloperidol 5 mg IM for the agitation
    2. B. Metoprolol 5 mg IV for rate control
    3. C. Labetalol 20 mg IV as the initial agent
    4. D. A benzodiazepine, aspirin, and nitroglycerin
    Show answer

    Answer: D. A benzodiazepine, aspirin, and nitroglycerin

    Benzodiazepines reduce sympathetic stimulation; beta blockers can cause unopposed alpha stimulation and worsen vasospasm.

56. A STEMI patient is 2.5 hours from a PCI center. The fibrinolytic checklist reveals a hemorrhagic stroke three years ago. This finding:

    1. A. Applies only if the stroke was in 3 months
    2. B. Is only a relative contraindication
    3. C. Is irrelevant after one year has passed
    4. D. Is an absolute contraindication to fibrinolytics
    Show answer

    Answer: D. Is an absolute contraindication to fibrinolytics

    Any prior intracranial hemorrhage is an absolute contraindication to fibrinolytic therapy.

57. A STEMI patient takes warfarin for atrial fibrillation. For fibrinolytic screening, current oral anticoagulant use is:

    1. A. A relative contraindication
    2. B. Not a contraindication at all
    3. C. An absolute contraindication
    4. D. An indication for a higher dose
    Show answer

    Answer: A. A relative contraindication

    Oral anticoagulant therapy increases bleeding risk and is listed among relative contraindications to fibrinolysis.

58. For a STEMI patient transported directly to a PCI-capable hospital, the recommended goal from first medical contact to device is:

    1. A. 12 hours or less
    2. B. 180 minutes or less
    3. C. 30 minutes or less
    4. D. 90 minutes or less
    Show answer

    Answer: D. 90 minutes or less

    AHA systems of care target first medical contact-to-device time of 90 minutes or less for direct transport.

59. A patient with an anterior STEMI has a BP of 168/100, crackles throughout, and an SpO2 of 88%. Which treatment combination is most appropriate?

    1. A. Metoprolol 5 mg IV along with aspirin
    2. B. A 500-mL normal saline bolus along with aspirin
    3. C. Morphine 10 mg IV with supine positioning
    4. D. CPAP and nitroglycerin, along with aspirin
    Show answer

    Answer: D. CPAP and nitroglycerin, along with aspirin

    Pulmonary edema with hypertension responds to nitrates for preload and afterload reduction and to CPAP for oxygenation.

60. A patient with an anterior STEMI is cool and clammy with crackles and a BP of 72/40. Which vasopressor is generally preferred?

    1. A. Norepinephrine infusion
    2. B. Dopamine at 5–20 mcg/kg/min
    3. C. Push-dose phenylephrine
    4. D. Nitroglycerin infusion
    Show answer

    Answer: A. Norepinephrine infusion

    Norepinephrine is commonly the first-line vasopressor in cardiogenic shock; large fluid volumes worsen pulmonary edema. Dopamine causes more dysrhythmias and is not preferred, pure-alpha phenylephrine raises afterload without supporting contractility, and nitroglycerin lowers an already low BP.

61. A patient with an inferior STEMI has sinus bradycardia at 44/min and a BP of 80/50. What is the most appropriate first drug?

    1. A. Metoprolol 5 mg IV
    2. B. Nitroglycerin 0.4 mg SL
    3. C. Diltiazem 10 mg IV
    4. D. Atropine 1 mg IV
    Show answer

    Answer: D. Atropine 1 mg IV

    Inferior MI often causes vagally mediated bradycardia that responds to atropine.

62. A patient with chest pain has 2 mm ST depression in V5, V6, I, and aVL and no ST elevation in any lead. What is the correct approach to fibrinolytics?

    1. A. Give them at half the dose
    2. B. Give them if the pain lasts 5 minutes
    3. C. Give them for ST depression too
    4. D. Withhold them for ST depression
    Show answer

    Answer: D. Withhold them for ST depression

    Fibrinolytics benefit patients with ST elevation (or new LBBB with a compatible picture) and do not help, and may harm, patients with ST depression or NSTE-ACS. Lateral ST depression in V5, V6, I, and aVL without elevation points to NSTE-ACS, so treat medically and transport for possible early catheterization. A reduced dose or a pain-duration rule does not make ST depression an indication.

63. A patient with known severe aortic stenosis has chest pain. Nitroglycerin should be used:

    1. A. Only at double doses to overcome the fixed obstruction
    2. B. Cautiously, because preload reduction can cause severe hypotension
    3. C. Liberally, because aortic stenosis raises the BP threshold
    4. D. Without concern, since the valve does not affect preload
    Show answer

    Answer: B. Cautiously, because preload reduction can cause severe hypotension

    A fixed outflow obstruction makes cardiac output preload-dependent, so vasodilators can drop BP sharply.

64. A patient with chest pain is intoxicated with alcohol. What is the main added concern with nitroglycerin?

    1. A. Alcohol speeds nitrate breakdown
    2. B. Alcohol masks the nitrate headache
    3. C. Additive vasodilation and hypotension
    4. D. Alcohol blocks nitroglycerin absorption
    Show answer

    Answer: C. Additive vasodilation and hypotension

    Alcohol is a vasodilator, and the nitroglycerin label warns that it can enhance nitrate-induced hypotension, so check the BP carefully before each dose and keep the patient seated or supine. Alcohol does not block absorption or speed nitrate breakdown, and a masked headache is not the danger; the drop in BP is.

65. A patient's chest pain resolves after one nitroglycerin. How should this be interpreted?

    1. A. It proves the pain is from esophageal spasm only
    2. B. It confirms the pain is cardiac and rules out other causes
    3. C. It rules out acute MI, so a 12-lead ECG can be skipped
    4. D. It does not reliably distinguish cardiac from noncardiac pain
    Show answer

    Answer: D. It does not reliably distinguish cardiac from noncardiac pain

    Pain relief after nitroglycerin is not diagnostic; esophageal spasm and other causes may also respond.

66. A woman taking sildenafil (Revatio) for pulmonary hypertension has chest pain. Regarding nitroglycerin:

    1. A. Withhold it; the PDE-5 interaction applies regardless of the indication
    2. B. Give it only as paste, which avoids the interaction completely
    3. C. Give it, because the interaction applies only to erectile dysfunction
    4. D. Give it at double dose to overcome the pulmonary vasoconstriction
    Show answer

    Answer: A. Withhold it; the PDE-5 interaction applies regardless of the indication

    Sildenafil causes the same dangerous hypotension with nitrates whether it is prescribed for pulmonary hypertension or erectile dysfunction.

67. A patient with nitroglycerin paste applied to the chest becomes hypotensive. What should be done first?

    1. A. Leave it on, since paste has no systemic effect
    2. B. Cover the paste with an occlusive dressing
    3. C. Apply a second inch to stabilize absorption
    4. D. Wipe off the paste and treat the hypotension
    Show answer

    Answer: D. Wipe off the paste and treat the hypotension

    Removing the paste stops further absorption; the patient is then positioned supine and given fluids as needed.

68. Why is morphine particularly risky in a patient with right ventricular infarction?

    1. A. It raises left ventricular afterload, which worsens the RV's forward flow
    2. B. It raises pulmonary pressures and worsens RV strain
    3. C. It triggers histamine-driven bronchospasm in most patients
    4. D. Its venodilation reduces the preload the right ventricle depends on
    Show answer

    Answer: D. Its venodilation reduces the preload the right ventricle depends on

    Like nitrates, morphine lowers preload and can cause marked hypotension in RV infarction. Morphine lowers rather than raises afterload, and histamine-related bronchospasm is uncommon and not the specific RV concern.

69. A patient with suspected ACS takes ibuprofen daily for arthritis. Why are NSAIDs other than aspirin avoided during ACS?

    1. A. They make the 12-lead ECG unreadable for STEMI
    2. B. They inactivate aspirin in the stomach completely
    3. C. They cause coronary vasodilation and steal syndrome
    4. D. They increase the risk of cardiovascular events and bleeding
    Show answer

    Answer: D. They increase the risk of cardiovascular events and bleeding

    AHA guidance recommends stopping non-aspirin NSAIDs in ACS because they are associated with reinfarction, heart failure, and death.

70. After a sublingual nitroglycerin, a patient's heart rate rises from 82 to 104 while the BP falls from 130/80 to 118/74. What explains the rise in heart rate?

    1. A. A new SVT that needs adenosine
    2. B. An allergic reaction to the drug
    3. C. Nitroglycerin's direct beta-1 effect
    4. D. Reflex tachycardia from vasodilation
    Show answer

    Answer: D. Reflex tachycardia from vasodilation

    Nitroglycerin lowers BP by vasodilation, and baroreceptors respond with a reflex increase in heart rate; it is an expected effect, but it raises oxygen demand, so monitor. A sinus rate that rises with a modest BP drop is not SVT. There are no signs of allergy. Nitroglycerin has no direct beta-1 action.

71. For a STEMI patient with true aspirin anaphylaxis, the receiving team may use which alternative antiplatelet strategy?

    1. A. A double dose of enteric-coated aspirin
    2. B. Diphenhydramine before a reduced aspirin dose
    3. C. A P2Y12 inhibitor such as clopidogrel
    4. D. An extra nitroglycerin dose instead of antiplatelets
    Show answer

    Answer: C. A P2Y12 inhibitor such as clopidogrel

    When aspirin cannot be used, a P2Y12 inhibitor such as clopidogrel provides antiplatelet therapy.

72. A STEMI patient who just received fibrinolytics suddenly develops a severe headache and confusion. What should you suspect?

    1. A. Intracranial hemorrhage
    2. B. Expected reperfusion effect
    3. C. Nitroglycerin headache only
    4. D. Hypoglycemia from fibrinolytics
    Show answer

    Answer: A. Intracranial hemorrhage

    Intracranial hemorrhage is the most feared complication of fibrinolysis; any neurologic change requires immediate evaluation.

73. Shortly after fibrinolytic therapy for STEMI, the patient develops an accelerated idioventricular rhythm at 80/min with a stable BP. This most likely represents:

    1. A. Hyperkalemia that needs calcium chloride
    2. B. Ventricular tachycardia that needs amiodarone
    3. C. Failure of fibrinolysis that needs a second fibrinolytic dose
    4. D. A reperfusion rhythm that usually needs no treatment
    Show answer

    Answer: D. A reperfusion rhythm that usually needs no treatment

    Accelerated idioventricular rhythm is a common, usually benign marker of reperfusion and is not suppressed with antidysrhythmics.