Cardiology Intensive Board Review, 3 ed.

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.A 72-year-old woman is admitted to the hospital with acute STEMI. She has no other past medical history. She underwent BMS to the left circumflex artery with good subsequent flow. She is now free of chest pain and feels well. Echocardiogram revealed an estimated ejection fraction of 30%. In addition to aspirin and clopidogrel what other medications must be considered in the patient’s discharge medication regimen?

a.Atorvastatin, lisinopril, and carvedilol

b.Atorvastatin, lisinopril, carvedilol, and warfarin

c.Atorvastatin, lisinopril, carvedilol, and eplerenone

d.Lisinopril, metoprolol, eplerenone, and niacin

28.The above patient had a brief (10 seconds) episode of nonsustained ventricular tachycardia (VT) at a rate of 180 beats per minute on the day of admission in the catheterization laboratory that spontaneously converted to sinus rhythm. What additional therapy is warranted for this patient?

a.Amiodarone at the time of discharge

b.Intravenous lidocaine in the hospital and amiodarone at discharge

c.Only intravenous lidocaine in the hospital

d.Implantable cardioverter–defibrillator (ICD) placement prior to discharge

e.Cardiac Resynchronization Therapy with Defibrillator (CRT-D) device placement prior to discharge

f.None of the above

29.A 45-year-old man presents to an emergency room with 30 minutes of crushing chest pain. The nearest catheterization laboratory is 45 minutes away and a decision to transfer for primary PCI is made. What is the optimal door in door out that has been associated with decreased mortality?

a.60 minutes

b.45 minutes

c.Within 120 minutes

d.Within 30 minutes

e.Within 24 hours

30.A 46-year-old man develops sudden chest pain and collapses to the ground. Bystander Cardio-Pulmonary Resuscitation (CPR) is immediately initiated. On EMS arrival 8 minutes later, he is noted to be in ventricular fibrillation and is promptly defibrillated. His ECG shows ST elevation in the inferior leads. The patient is comatose and is intubated for airway protection. Apart from performance of primary PCI which of the following actions is associated with mortality benefit?

a.Bolus of 2 L of normal saline

b.Intravenous lidocaine initiation to prevent recurrent arrest

c.Initiation of transvenous pacing to prevent polymorphic VT

d.Initiation of hypothermia protocol

e.Placement on Extracorporeal Membrane Oxygenation (ECMO)

31.An 85-year-old man presents with increasing intensity of his typical angina pain associated with shortness of breath. His ECG is unchanged from prior tracings. He has a history of established coronary artery disease and has previously refused revascularization. A decision is made to manage him conservatively. Which of the following interventions would be considered inappropriate?

a.Initiation of anticoagulation with fondaparinux

b.Treatment with clopidogrel 300 mg followed by 75 mg daily

c.Initiate treatment with prasugrel bolus 60 mg followed by 5 mg once daily

d.Increase the dosage of prior β-blocker therapy

e.Continue treatment with aspirin

32.Which of the following is not a direct thrombin inhibitor?

a.Bivalirudin

b.Argatroban

c.Hirudin

d.Dabigatran

e.Apixaban

33.Which of the following is true regarding pericarditis in acute MI?

a.Fibrinolysis has no effect on the incidence of pericarditis in MI.

b.Fibrinolysis reduces the incidence of pericarditis in MI.

c.Fibrinolysis increases the incidence of pericarditis in MI.

d.No data have examined this issue.

34.Which of the following are potential indications for IABP in the setting of acute MI?

a.Refractory ischemia despite intensive medical therapy

b.STEMI and secondary acute mitral regurgitation

c.STEMI and refractory polymorphic VT

d.STEMI and refractory cardiogenic shock

e.All of the above

35.A 66-year-old man presents to the emergency with complaints of on–off episodes of chest discomfort for the last 24 hours. Each episode lasts from 15 to 45 minutes and occurs at rest. He denies any history of similar pain in the past. He has a past medical history of hypertension, diabetes mellitus, and peripheral vascular disease. He is an active smoker with 40 pack-year history. An ECG done reveals nonspecific ST-T wave changes. Troponin T is elevated at 0.62. He is taken to the catheterization laboratory and a 90% lesion is noted in first diagonal via a transfemoral approach. He is treated with overlapping BMSs with subsequent TIMI-3 flow. He is transferred to CCU in stable condition. About 4 hours later, the patient develops hypotension with BP of 80/40 mmHg and heart rate of 110 per minute. There is no jugular venous distension. He is pale, diaphoretic, and dizzy. Cardiac auscultation is unchanged. A repeat ECG done is similar to admission ECG. No pericardial effusion is noted on a bedside echocardiogram. Which of the following is most likely to identify the cause of his current condition?

a.Repeat left heart catheterization

b.CT chest with contrast

c.CT abdomen without contrast

d.Chest X-ray

e.Bedside transesophageal echocardiography

36.A 48-year-old man presents to the emergency room agitated after abusing cocaine. His heart rate is 110 per minute, his BP is 200/120 mmHg, and an ECG shows ST elevation in the inferior leads. On examination he is diaphoretic with clear lung sounds. Auscultation is pertinent for a diastolic murmur at the base of the heart that accentuates with expiration. What is the appropriate next step for definitive diagnostic evaluation?

a.Performance of a CT pulmonary embolus protocol

b.Performance of a gated CT of the aorta

c.Activation of the catheterization laboratory for primary PCI

d.Initiation of intravenous heparin and load with ticagrelor

e.Performance of a two-dimensional echocardiogram at the bedside

37.A 78-year-old man calls 911 because he has sudden-onset chest pain. On EMS arrival he has a BP of 120/80 mmHg and a heart rate of 80 beats per minute. His lungs are clear to auscultation and he has a left ventricular (LV) S4noted. ECG done on the field confirms an anterior MI with ST elevation from V1 to V4. He is given an aspirin and a sublingual nitroglycerin and transfer is initiated. Within 5 minutes while en route his BP is noted to be 60 mmHg and a saline bolus is initiated. Cardiovascular examination is unchanged and no murmurs are noted. Which of the following scenarios may likely explain his observed hemodynamic deterioration?

a.Hypotension resulting from bleeding due to administration of aspirin

b.Right ventricular (RV) infarction

c.Anaphylaxis reaction from aspirin

d.Recent exposure to a phosphodiesterase 5 inhibitor

e.Massive pulmonary embolism

38.A 42-year-old mother is visiting her child who is undergoing chemotherapy in the Children’s Hospital. She suddenly develops chest pain and is noted to be nauseous and diaphoretic. An ECG is performed (Fig. 3-1). On angiography, the coronaries are free of significant epicardial stenosis. A ventriculogram shows apical ballooning with an LVEF of 25%. The patient is admitted to the CCU. Which of the following statements will most likely define her clinical course?

a.She will likely require an ICD as LV function is unlikely to recover.

b.Her prognosis will likely be excellent with full recovery of LV function.

c.She is at risk for recurrent atherosclerotic ischemic events.

d.Indefinite anticoagulation with warfarin will be indicated.

e.She is at higher risk for a malignancy in the ensuing year.

Figure 3.1

39.A 91-year-old man with a history of prior CABGx2 is brought from the nursing home with shortness of breath and hypotension. He is debilitated and has required 24/7 nursing care for activities of daily living. His ECG shows diffuse ST-segment depression, and he is noted to be in pulmonary edema. His heart rate is 110 per minute and his BP is 70/40 mmHg. He has a recent stroke 3 months prior and has stage 4 chronic kidney disease. History is also relevant for a diagnosis of prostate cancer with extensive metastasis to his spine. Which of the following is indicated?

a.Discussion with the family explaining his poor prognosis and the near futility of escalating care

b.Emergent catheterization and revascularization as indicated by anatomy

c.Placement of an IABP for medical stabilization

d.Plan for emergent dialysis

e.Urgent oncology consultation to estimate his prognosis from his prostate cancer

40.A 64-year-old man presents with ST elevation and is taken for primary angioplasty (see Fig. 3-2). Identify the infarct-related artery?

a.LAD

b.Diagonal

c.RCA

d.Left Circumflex

e.Obtuse marginal

41.A 45-year-old man is status post hip replacement. He develops sudden-onset shortness of breath. On examination, he is hypotensive with a BP of 80/40 mmHg. An ECG shows sinus tachycardia at 100 beats per minute with ST elevation in V1 to V2. A bedside echo is performed (Fig. 3-3). What is the most appropriate intervention?

a.Activate catheterization laboratory to perform a primary PCI.

b.Perform a CT angiogram to rule out a dissection.

c.Initiate intravenous heparin and assess risks and benefits of fibrinolysis.

d.Perform a saline contrast study to assess right-to-left shunt.

e.Initiate antibiotics and perform blood cultures.

Figure 3.2

Figure 3.3

42.A 75-year-old woman presented with shortness of breath and generalized malaise of 1-week duration. Her heart rate was 90 per minute and BP was 90/50 mmHg. Examination revealed rales in bilateral lung bases, an elevated jugular venous pulse, and a loud systolic murmur in the left parasternal area. An echo (Fig. 3-4) was performed. What is the likely infarct-related artery?

a.Proximal LAD

b.Distal LAD

c.Obtuse marginal in a dominant circumflex

d.Mid-RCA in dominant RCA

e.Proximal nondominant RCA

Figure 3.4

43.A 42-year-old male nurse in a rural emergency room develops crushing chest pain 30 minutes after he smoked a cigarette during a break in his shift. An ECG (Fig. 3-5) is performed. What is the most appropriate intervention?

a.Load with clopidogrel 600 mg and initiate heparin for a diagnosis of NSTEMI ACS.

b.Load with prasugrel 60 mg once daily and transfer for primary PCI to a laboratory 4 hours away.

c.Treat with intravenous verapamil for vasospasm.

d.Initiate fibrinolytic therapy with reteplase with adjunctive treatment with aspirin and intravenous heparin.

e.Treat with intravenous metoprolol 5 mg three times.

Figure 3.5