Acute Myocardial Infarction
Venu Menon • Bhuvnesh Aggarwal
QUESTIONS
1.Which one of the following statements is true regarding trends in incidence of acute coronary syndrome (ACS) in the United States?
a.Percentage of ACS with ST-segment elevation myocardial infarction (STEMI) is declining.
b.Percentage of ACS with non–ST-segment elevation myocardial infarction (NSTEMI) is declining.
c.Percentage of ACS with unstable angina (UA) is increasing.
d.Overall incidence of ACS is decreasing.
e.All of the above.
2.Which of the following processes represents the dominant initiating event in the pathogenesis of an ACS?
a.Plaque rupture
b.Plaque erosion
c.Platelet activation
d.Venous stasis
e.None of the above
3.What is the most important clinical predictor of 30-day mortality in a patient presenting with acute STEMI?
a.Age
b.Systolic blood pressure (BP)
c.Heart rate
d.Killip classification stage
e.Location of myocardial infarction (MI)
4.Which of the following is a prodrug and requires bioactivation?
a.Aspirin
b.Clopidogrel
c.Prasugrel
d.Ticagrelor
e.Both b and c
5.Which of the following statements regarding prasugrel is true?
a.Prasugrel has faster onset of action when compared with clopidogrel.
b.Unlike clopidogrel, prasugrel is not influenced by polymorphisms in cytochrome P450 enzyme pathway.
c.Prasugrel provided no net mortality benefit when compared with clopidogrel in patients with ACS in the Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition with Prasugrel–Thrombolysis in Myocardial Infarction (TRITON-TIMI)-38 trial.
d.Prasugrel is contraindicated in patients with a prior history of transient ischemic attack (TIA)/stroke.
e.All of the above.
6.A 72-year-old presents with sudden-onset chest pain at a local emergency department. He has a past medical history significant for hypertension, hyperlipidemia, and gastroesophageal reflux disease. On examination his BP is 95/60 mmHg and heart rate is 90 beats per minute and he is breathing at 90% on ambient air. He reports this is the first time he has had any episode of chest pain. His electrocardiogram (ECG) reveals ST elevation in V1 to V4. The nearest hospital with percutaneous coronary intervention (PCI) capability is 3 hours away. What is the next step in management?
a.Perform fibrinolysis; administer unfractionated heparin, aspirin, and clopidogrel; and admit to hospital.
b.Administer unfractionated heparin, aspirin, and clopidogrel and admit to hospital.
c.Administer unfractionated heparin, aspirin, and clopidogrel followed by transfer to PCI-capable hospital.
d.Computed tomography (CT) of the chest with intravenous contrast.
e.Perform fibrinolysis; low-molecular-weight heparin (LMWH), aspirin, and clopidogrel; and transfer to the hospital for possible PCI.
7.The above patient is given intravenous tenecteplase and started on aspirin, clopidogrel, and unfractionated heparin. Thirty minutes into treatment his chest pain has now completely resolved. A repeat ECG shows complete resolution of the earlier noted ST elevation. What is the next step in management?
a.Continue unfractionated heparin, aspirin, and clopidogrel and transfer to the nearest hospital with PCI capabilities.
b.Admit to local hospital for observation.
c.Discharge home with outpatient follow-up following a submaximal stress test.
d.Discharge home with plan for possible angiography after 4 to 6 weeks.
e.None of the above.
8.Which of the following is true for management of acute STEMI?
a.The administration of aspirin has a much larger treatment effect than streptokinase.
b.The administration of streptokinase has a much larger effect than aspirin.
c.Streptokinase and aspirin each have a similar effect on outcome.
d.When streptokinase and aspirin are used together, their effects are blunted.
e.None of the above.
9.Which of the following is the mechanism of action of ticagrelor?
a.Thromboxane inhibition
b.Glycoprotein (GP) IIb/IIIa receptor blockade
c.Adenosine diphosphate blockade
d.Increase in cyclic adenosine monophosphate production
e.Free radical scavenger
10.Which of the following is true regarding use of GP IIb/IIIa inhibitors in STEMI?
a.Routine upstream use of GP IIb/IIIa inhibitors has been shown to reduce target vessel revascularization (TVR).
b.Routine GP IIb/IIIa inhibitor use is associated with reduced incidence of recurrent MI.
c.Routine GP IIb/IIIa inhibitor use is associated with increased risk of bleeding.
d.Small-molecule GP IIb/IIIa inhibitor use has been shown to reduce 30-day mortality.
e.Upstream use of GP IIb/IIIa inhibitors is given a class I indication in current American College of Cardiology (ACC)/American Heart Association (AHA) guidelines.
11.In the setting of primary angioplasty for acute MI, which of the following have stents been convincingly shown to do compared with balloon angioplasty alone?
a.Decrease subsequent repeat TVR.
b.Decrease long-term mortality.
c.Decrease long-term MI risk.
d.Decrease the incidence of heart failure.
12.Which of the following is true about reteplase in Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO-III)?
a.It had a significantly higher rate of stroke than alteplase.
b.It significantly reduced mortality compared with alteplase.
c.It significantly reduced mortality, but increased stroke compared with alteplase.
d.It had similar rates of mortality compared with alteplase.
13.Which of the following statements is true regarding non–ST-segment elevation (NSTE)-ACS?
a.NSTEMI has poorer prognosis than UA.
b.Elevated troponin is associated with worse prognosis in NSTE-ACS.
c.ST-segment deviation is associated with increased risk of long-term ischemic events.
d.One in five patients with NSTEMI has normal ECG.
e.All of the above.
14.A 46-year-old man presents to the emergency with complaints of sudden, severe chest pain radiating to his right arm. He admits to snorting crack cocaine 2 hours prior to the development of chest pain. His BP is 180/100 mmHg and heart rate is 96 per minute. An ECG done reveals downsloping ST depression and T-wave inversion in V2 to V4. What is the next best step in management?
a.Administer aspirin, sublingual nitroglycerin, and intravenous metoprolol.
b.Administer aspirin and sublingual nitroglycerin.
c.Administer aspirin, sublingual nitroglycerin, and heparin.
d.Administer activated charcoal.
15.The patient is started on aspirin, nitroglycerin, and intravenous heparin. He continues to have severe substernal chest pain. Repeat ECG is unchanged. Troponin T is borderline elevated to 0.04 ng/mL. What is the next best step in management?
a.Activate the catheterization laboratory for emergent left heart catheterization.
b.Administer diazepam and let the patient rest.
c.Administer tissue plasminogen activator.
d.Cycle cardiac biomarkers and monitor the patient.
e.None of the above.
16.A 64-year-old man is brought to the emergency room for complaints of chest pressure, difficulty breathing, and palpitations. He has a past medical history of hypertension and type 2 diabetes and ischemic stroke and his home medications include metformin, glyburide, lisinopril, and aspirin. ECG on arrival reveals ST-segment elevation in leads I, avL and V5 to V6. Catheterization laboratory is activated and the patient is given 325 mg of aspirin and started on nitroglycerin drip. Which of the following additional therapies is currently indicated?
a.Clopidogrel 300 mg, fondaparinux, and atorvastatin 80 mg
b.Prasugrel 60 mg, unfractionated heparin, and atorvastatin 80 mg
c.Ticagrelor 90 mg, unfractionated heparin, and atorvastatin 80 mg
d.Clopidogrel 600 mg, bivalirudin drip, and atorvastatin 80 mg
e.Both a and d are correct
17.Which of the following is true regarding adjunctive medical therapy in patients with acute MI receiving primary PCI?
a.Routine intravenous β-blocker within 24 hours improves mortality.
b.Intravenous angiotensin-converting enzyme inhibitor (ACEI) within 24 hours improves mortality.
c.Mortality benefit with routine intravenous nitroglycerin is not established.
d.Intravenous magnesium improves mortality when used as an adjunct to reperfusion.
18.Which of the following statements is incorrect with regard to acute MI?
a.Primary PCI is associated with reduced rate of intracerebral hemorrhage as compared with fibrinolysis.
b.If rapidly available, primary PCI provides a mortality benefit as compared with fibrinolysis.
c.Primary PCI may be considered 12 hours after symptom onset in patients with signs of ongoing ischemia.
d.Routine PCI of the totally occluded infarct-related artery should be avoided after 24 hours of presentation in hemodynamically stable patients without signs of ischemia.
e.Fibrinolysis should be considered 12 hours after symptom onset in hemodynamically stable patients with signs of ongoing ischemia.
19.Which of the following is an absolute contraindication for use of fibrinolytics for acute MI?
a.History of ischemic stroke
b.Pregnancy
c.Concomitant use of warfarin for another indication
d.Suspected aortic dissection
e.History of seizure disorder
f.All of the above
20.Which of the statements is true regarding ventricular septal rupture (VSR) after acute MI?
a.VSR is more common in men when compared with women.
b.VSR is more likely after recurrent MI.
c.Presence of collateral circulation in the infarct zone reduces risk of VSR.
d.Fibrinolysis is associated with increased risk of VSR.
e.VSR is more likely after anterior wall MI as compared with nonanterior wall MI.
21.An 82-year-old woman calls 911 after developing sudden-onset chest pain, nausea, and lightheadedness. An ECG done by emergency medical service (EMS) reveals 3-mm ST elevation in leads II, III, and aVF. The nearest catheterization laboratory is activated and the patient undergoes PCI to the right coronary artery (RCA) with drug-eluting stent. She is transferred to the intensive care unit (ICU) in stable condition after the procedure. Two days later, the patient develops sudden-onset lightheadedness and left-sided chest pain. Her vitals reveal BP of 115/60 mmHg, heart rate of 90 per minute and SaO2 of 92% on ambient air. Physical examination reveals new systolic murmur at the left sternal border that radiates to the apex. An ECG done immediately reveals Q waves in leads II, III, and aVF. No new ST-T changes are noted. A stat bedside echocardiogram reveals basal septal VSR with left-to-right shunt and moderate mitral regurgitation. A pulmonary artery (PA) catheter is placed and shunt fraction (Qp/Qs) is calculated at 1.3. What is the next best step in management?
a.Left heart catheterization with ventriculography for better assessment of septum
b.Cardiac magnetic resonance imaging (MRI) to better assess the size of septal rupture
c.Intravenous nitroprusside for afterload reduction
d.Intra-aortic balloon pulsation (IABP) placement
e.Urgent surgical repair
22.Which of the following statements is true regarding ventricular free wall rupture complicating acute MI?
a.Incidence of ventricular free wall rupture is higher after fibrinolysis when compared with that after primary angioplasty.
b.Ventricular free wall rupture usually presents with acute-onset signs and symptoms of cardiac tamponade, or sudden death.
c.Type I rupture usually occurs within 24 hours of MI.
d.All of the above.
23.Which of the following is true?
a.Ventricular aneurysm is more common than ventricular pseudoaneurysm after MI.
b.Most ventricular pseudoaneurysms resolve over time and require no specific therapy.
c.Ventricular aneurysm is more common with inferior wall MI when compared with anterior MI.
d.Ventricular pseudoaneurysm is more common with anterior wall MI as compared with inferior wall MI.
e.All of the above.
24.A 63-year-old woman presents to the clinic after an episode of sudden transient left-sided vision loss. Symptoms lasted about 15 minutes with spontaneous resolution. Her past medical history is significant for an anterior MI 3 weeks ago treated with PCI with bare metal stent (BMS) to the left anterior descending artery (LAD). Other medical conditions include hypertension, type 2 diabetes mellitus, and hyperlipidemia. Current medications are aspirin, prasugrel, atorvastatin, metformin, and metoprolol. Physical examination is normal. There are no carotid bruits. Ophthalmologic examination is within normal limits. An ECG reveals sinus rhythm with persistent ST elevations in V2 to V4. What is the next step in management?
a.Exercise stress test with nuclear imaging
b.MRI of the brain with contrast
c.Carotid ultrasound
d.Left heart catheterization
e.Transthoracic echocardiogram
25.A previously healthy and independently functional 77-year-old man is brought to the catheterization laboratory after developing sudden-onset chest pain radiating to the jaw and shortness of breath. ECG by EMS during transfer revealed ST elevation in V2 to V4 and leads I and aVL. The patient was in respiratory distress during transfer requiring emergent endotracheal intubation. His BP is 70/30 mmHg and heart rate is 110 per minute. Angiogram reveals fresh mural thrombus in proximal LAD, which is stented with BMS with resultant TIMI-2 flow. No significant disease is noted in the RCA and circumflex vessels. An echo reveals a left ventricular ejection fraction (LVEF) of 30% with no significant valvular pathology. He is subsequently transferred to the critical care unit (CCU) in critical condition. His current vital signs are as follows: BP 80/40 mmHg, HR 120 beats per minute, and SaO of 92% on 60% FiO2. A PA catheter is placed. Which of the following readings is associated with worst prognosis in this patient?
a.Pulmonary capillary wedge pressure (PCWP) 30, Cardiac Index (CI) 1.6
b.PCWP 24, CI 3.2
c.PCWP 10, CI 1.8
d.PCWP 16, CI 2.4
26.What is the next step to be considered in the management of this patient?
a.Consideration for advanced mechanical support
b.IV nitroprusside
c.Refer for urgent coronary artery bypass grafting (CABG)
d.Repeat left heart catheterization
27.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
