MOC Questions

Cardiology Review® Online, October 2006, Volume 23, Issue 10

The following questions can assist candidates for the Maintenance of Certification Exam in Cardiovascular Disease in preparing for this test. We hope you find this helpful and welcome your feedback.

Preparing for the American Board of Internal Medicine Maintenance of Certification Exam

Questions

1. A 63-year-old woman is referred to your office for evaluation of atrial fibrillation. She had presented to her family practitioner for a routine annual examination, had an irregular pulse, and her electrocardiogram (ECG) showed atrial fibrillation at a rate of approximately 80 beats per minute and nonspecific ST- and T-wave changes. At that time, she was on no medications except calcium supplements daily and a bisphosphonate weekly for osteoporosis. Her history is otherwise negative. The family practitioner started the patient on aspirin, 325 mg daily, found normal thyroid studies and chest x-ray, and performed an echocardiogram, which was essentially unremarkable. She is unaware of palpitations, but is concerned about the rhythm abnormality. An ECG at the time of your consultation is similar to the tracing from the primary physician’s office.

At this point, the most appropriate management would include:

a) stop aspirin, start warfarin, assess rate control with 24-hour Holter monitor, perform stress sestamibi study.

b) reduce aspirin to 81 mg daily, start warfarin, start digoxin and a proton pump inhibitor.

c) continue aspirin, assess rate control with 24-hour Holter monitor.

d) stop aspirin, start warfarin, arrange for outpatient transesophageal-facilitated cardioversion in the next week.

e) stop aspirin, start warfarin, arrange for elective cardioversion after international normalized ratio is therapeutic for 4 weeks.

2. You are asked to see a hospitalized 77-year-old man who has a nonhealing ulcer on his right ankle and peripheral vascular disease. A vascular surgeon requested “cardiology clearance” for femoral-popliteal bypass planned the next day. The patient has a history of hypertension and diabetes, both well controlled on oral medications including metformin, glyburide, amlodipine, hydrochlorothiazide, and valsartan. Prior to admission, he played golf twice weekly, but was otherwise sedentary. There was no history of angina, myocardial infarction (MI), or heart failure. He did not experience claudication. He had a stress test 6 years ago that he recalls was “fine.”

On examination, his blood pressure was 138/72 mm Hg and his pulse was 78 and regular. His jugular pulse was normal, lung fields clear, and cardiac exam showed an S4 and a grade 1 ejection systolic murmur. There were no peripheral arterial bruits but pulses in both legs were diminished. The ECG showed only minor nonspecific ST- and T-wave abnormalities.

At this point, cardiologist recommendations should include:

a) cancel surgery, schedule echocardiogram and adenosine sestamibi stress test.

b) clear for surgery but suggest intraoperative intravenous nitroglycerin and schedule creatinine kinase, CK-MB, and troponin blood tests and ECGs at 6-hour intervals postoperatively.

c) begin atenolol 25 mg twice daily, suggest surgery proceed as planned at low risk (<2% major cardiac complications).

d) schedule cardiac catheterization, then clear for surgery if coronary disease is absent or mild.

e) schedule adenosine cardiolyte, and clear for surgery if images are normal or show only small perfusion abnormalities.

3. A 47-year-old man with diabetes mellitus sustains an acute anterior wall MI. He undergoes early primary angioplasty and implantation of a tacrolimus-eluting stent in the left anterior descending artery. At the time of his catheterization procedure, his ejection fraction is 29% with anteroapical hypokinesis. His hospital course is uncomplicated by recurrent angina or heart failure, and no ventricular arrhythmias are seen. At the time of hospital discharge, which of the following medications might be expected to lead to reduced mortality over the next year?

a) digoxin.

b) isosorbide dinitrate and hydralazine.

c) amiloride.

d) dipyridamole.

e) trandolapril.

4. A 77-year-old woman is admitted with progressive shortness of breath, lower extremity edema, and an elevated level of B-type natriuretic peptide. She has a history of hypertension. Her exam is compatible with congestive heart failure. Echocardiography demonstrates mild concentric left ventricular hypertrophy, normal left ventricular systolic function, trace mitral and tricuspid regurgitation, and normal aortic valve flow velocity during systole. Which of the following treatments is best supported by clinical trials in this population?

a) angiotensin-converting enzyme (ACE) inhibitors.

b) diuretics.

c) rate-slowing calcium channel blockers (eg, verapamil or diltiazem).

d) atenolol.

e) candesartan.

5. A 74-year-old woman presents to a rural emergency department with 4 hours of retrosternal chest pain and pressure, shortness of breath, and diaphoresis. Initial ECG shows 0.4-0.5 mV of ST segment elevation of leads II, III, aVF, and V5 and V6 with ST depression in V1 and V2.

She has a history of mild emphysema and borderline hypertension. She has no prior stroke, diabetes, or known renal or hematologic diseases. There are no known allergies. On exam, her blood pressure is 110/62 mm Hg, heart rate is 90, and she is warm and dry. The lung fields are clear, and an S4 gallop is heard.

Ground transportation to an interventional catheterization facility is 4 hours away, and a medical helicopter could transport the patient to the catheterization facility in at least 2 1/2 hours. At this point, the most rational therapy would include:

a) aspirin, heparin, and air transportation to the catheterization laboratory for emergency angioplasty.

b) aspirin, enoxaparin, clopidogrel, and weight-adjusted tenecteplase.

c) aspirin, enoxaparin, eptifibatide, and 1/2 dose weight-adjusted tenecteplase.

d) aspirin, enoxaparin, eptifibatide, and 1/2 dose weight-adjusted tenecteplase with ground transportation to the interventional hospital for further evaluation.

e) aspirin, heparin, eptifibatide.

For the following items, the stem will be followed by a number of multiple choice questions. The references pertain to the stem and all questions.

Stem, Part 1

A 66-year-old woman with a history of hypertension controlled on 1 medication was seen in the emergency department of a community hospital complaining of left-sided chest pain radiating down her left arm. The patient remarked that the pain started while she was doing last-minute shopping in preparation for her granddaughter’s wedding. While being interviewed in the emergency department, the patient also realized that she had been “breathless” with normal activity for the past 2 days. Her initial evaluation included a 12-lead ECG demonstrating a normal rhythm with multiple premature atrial complexes and upsloping ST segment elevation in leads V2-V4. Her initial cardiac enzymes showed troponin I was 0.22 ng/mL (normal < 0.03 ng/mL), but initial CK and CK-MB levels were normal. Other laboratory values were unremarkable except for a brain natriuretic peptide level of 425 pg/mL. The patient’s blood pressure was 134/86 mm Hg and her heart rate was 72. The patient’s physical exam was significant for a displaced point of maximum impulse, slightly irregular rate and rhythm, and faint scattered crackles in the lung bases that cleared with cough. The patient was treated according to the institutional acute coronary syndrome (ACS) protocol with aspirin, low-molecular-weight heparin, metoprolol, and eptifibatide. In hospital, the medical therapy initiated in the emergency department was continued. A second and third set of cardiac enzymes indicated that the troponin-I level plateaued at 0.88 ng/mL. The patient was scheduled for a transthoracic echocardiogram and put on the schedule for a cardiac catheterization, coronary angiography, and left ventriculography the next day.

6. The differential diagnosis for this patient would include all of the following except:

a) Non—ST segment elevation myocardial infarction (NSTEMI).

b) Acute transmural MI.

c) Left ventricular (LV) aneurysm.

d) Myocarditis.

e) Transient LV apical ballooning (Takotsubo cardiomyopathy).

7. In which of the following conditions (in the differential diagnosis) is the ECG abnormal?

a) ACS.

b) Transient LV apical ballooning (Takotsubo cardiomyopathy).

c) LV aneurysm.

d) All of the above.

Stem, Part 2

The patient underwent transthoracic echocardiography. The overall LV ejection fraction was 35%. There was a significant wall motion abnormality in the apical and anteroapical region. Cardiac catheterization revealed the following: coronary angiography demonstrated minimal irregularities but no significant coronary artery stenoses. A left ventriculogram showed a calculated ejection fraction of 30% with the appearance of apical akinesis and hyperkinesis of the basal walls. The patient was discharged after 48 hours in the hospital on aspirin and beta blockers, with improvement in her symptoms.

8. The discharge diagnosis for this patient would be:

a) NSTEMI.

b) Transient LV apical ballooning (Takotsubo cardiomyopathy).

c) LV aneurysm.

d) Transmural MI.

e) None of the above.

9. Possible etiologies for the discharge diagnosis include:

a) Transmural ischemia secondary to coronary artery embolization.

b) MI.

c) Catecholamine excess.

d) Chest trauma.

10. Follow-up echocardiogram in 4 weeks would most likely demonstrate the following:

a) Persistent ballooning of the LV apex.

b) Anterior wall motion abnormality.

c) Severe mitral regurgitation.

d) Normal LV function without wall motion abnormalities.

1: c Stroke prevention in patients younger than 65 (or maybe 75) years old who have no risk factors for stroke and normal LV function is most safely accomplished with aspirin. Warfarin has better stroke preventive effects, but a higher bleeding profile, so when stroke risk is low, aspirin is preferred. Current guidelines recommend some clinical assessment of the extent of rate control both at rest and with activity; this can be accomplished with a 24-hour monitor, a brief walk around the office, or a nonimaging stress test. This patient does not meet “appropriateness criteria” for stress sestamibi testing on the basis of the arrhythmia. Achieving and maintaining sinus rhythm with cardioversion and/or antiarrhythmic drugs is a reasonable alternative, but is not preferred over rate control, particularly in an asymptomatic patient with normal LV function, even if atrial fibrillation is chronic.

Answers

Circulation

Fuster V, Ryden LE, Asinger RW, for the American College of Cardiology/American Heart Association Task Force on Practice Guidelines; European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients with Atrial Fibrillation); North American Society of Pacing and Electrophysiology. ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation: executive summary a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients with Atrial Fibrillation) developed in collaboration with the North American Society of Pacing and Electrophysiology. . 2001;104(17):2118-2150.

2: c Preoperative evaluation guidelines suggest consideration of both the patient factors and characteristics of the operation that might increase risk of death, MI, or other cardiac complication of noncardiac surgery. Here, the patient has risk factors for coronary disease, but no clinical manifestations of angina, heart failure, or aortic stenosis, and a fair functional status. The operation is moderate risk, involving vascular beds but not the thoracic or abdominal cavity or the aorta. Therefore, no preoperative testing for coronary disease is necessary. A recent update to the guidelines emphasizes the protective role of beta blockers in reducing risks of high-risk patients or high-risk operations, particularly vascular surgery.

Eagle KA, Berger PB, Calkins H, et al. Perioperative cardiovascular evaluation for noncardiac surgery update. Available at:

. Accessed May 11, 2006.

www.acc.org/clinical/guidelines/perio/update/periupdate_index.htm

J Am Coll Cardiol

Eagle KA, Berger PB, Calkins H, et al. ACC/AHA guideline update for perioperative cardiovascular evaluation for noncardiac surgery. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1996 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). . 2002;39:542-553.

J Am Coll Cardiol

Fleisher LA, Beckman JA, Brown KA, et al. AHA/ACC 2006 guideline update on perioperative evaluation for noncardiac surgery: focused update on perioperative beta-blocker therapy. . 2006;47(11):2343-2355.

3: e The patient would benefit from aspirin, clopidogrel, statin, and a beta blocker, based on multiple trials showing prevention of death and reinfarction. Angiotensin-converting enzyme inhibitors such as trandolapril have been demonstrated to reduce mortality after MI, particularly in the presence of LV dysfunction or heart failure. Digoxin has never been shown to reduce mortality. Isosorbide dinitrate and hydralazine may reduce mortality in patients with stable advanced heart failure but not soon after MI. Amiloride is a potassium-sparing diuretic and dipyridamole an old antiplatelet agent, neither of which has been evaluated early post MI. Eplerenone reduces mortality in post-MI LV dysfunction as well.

J Am Coll Cardiol

Smith SC Jr, Allen J, Blair SN, et al. AHA/ACC Guidelines for Secondary Prevention for Patients with Coronary and Other Atherosclerotic Vascular Disease: 2006 Update—Endorsed by the National Heart, Lung, and Blood Institute. . 2006;47:2130-2139.

4: e Heart failure with preserved systolic function is a common form of heart failure, but has not been extensively studied in clinical trials, which for the most part have only included patients with diminished systolic function. One exception is the CHARM trial of candesartan, which included a subset of patients with heart failure and preserved systolic function, and demonstrated that heart failure readmissions were reduced, although mortality was not. Judicious use of diuretics to treat congestion and beta blockers are both generally recommended, but neither have been well studied and are therefore not supported by clinical trials. Rate-slowing calcium blockers are not supported by trials evidence. Angiotensin-converting enzyme inhibitors are well established for systolic failure and are supported by mechanistic rationale in diastolic failure, but clinical data are again lacking.

Yusuf S, Pfeffer MA, Swedberg K, et al. Effects of candesartan in patients with chronic heart failure and preserved left-ventricular ejection fraction: the CHARM-Preserved Trial. Lancet. 2003;362(9386):777-781.

5: b American Heart Association/American College of Cardiology guidelines suggest primary angioplasty is preferred over thrombolysis for ST elevation MI if percutaneous transluminal coronary angioplasty can be performed within 90 (±30) minutes; otherwise, thrombolysis should be considered. Although either unfractionated or low-molecular-weight heparin (eg, enoxaparin) can be used, unfractionated heparin is preferred if renal impairment is present. The recent COMMIT and CLARITY-TIMI-28 trials support the use of clopidogrel as an adjunct to thrombolysis. Large clinical trials have shown no benefit and increased bleeding when full- or half-dose thrombolytics are used with eptifibatide or other platelet glycoprotein IIb/IIIa receptor blockers.

Lancet

Chen ZM, Jiang LX, Chen YP, et al for the COMMIT (ClOpidogrel and Metoprolol in Myocardial Infarction Trial) collaborative group. Addition of clopidogrel to aspirin in 45,852 patients with acute myocardial infarction: randomised placebo-controlled trial. . 2005;366(9497):1607-1621.

N Engl J Med

Sabatine MS, Cannon CP, Gibson CM, et al for the CLARITY-TIMI 28 Investigators. Addition of clopidogrel to aspirin and fibrinolytic therapy for myocardial infarction with ST-segment elevation. . 2005;352(12):1179-1189.

6: c The diagnosis of LV aneurysm is excluded due to the fact that the patient manifests chest pain and had a positive troponin level on initial evaluation. Left ventricular aneurysm formation is the response of the myocardium to a large transmural anterior MI, and is not an acute process. In general, troponin-I does not rise to significant levels with an LV aneurysm, but does with the other diagnoses. Non-ST segment elevation MI and transmural MI manifest with high cardiac enzyme levels, whereas Takotsubo cardiomyopathy shows mild enzyme elevations.

7: d The ECG is abnormal in all of the above conditions. Acute coronary syndromes typically have ST segment elevation or depression. Left ventricular aneurysm manifests as persistent ST segment elevation. Transient LV apical ballooning (Takotsubo cardiomyopathy) manifests as a number of possible ECG abnormalities, including ST segment elevation, deep T-wave inversions, Q-waves, ST segment depression, and prolonged QT intervals. The ECG changes in Takotsubo cardiomyopathy may mimic the entire spectrum of ACS.

8: b Transient LV apical ballooning or Takotsubo cardiomyopathy typically manifests in elderly women. Stress is believed to be a causative agent. Patients with this condition present with chest pain and mild symptoms of heart failure, similar to ACS. The ECG and cardiac enzymes are usually abnormal. Non-ST segment elevation MI and MI would usually present with abnormal coronary angiography. Left ventricular aneurysm would have a negative workup with regards to cardiac enzymes.

9: c Although the exact etiology is unknown, studies suggest that excessive catecholamine levels may lead to the myocardial dysfunction associated with Takotsubo cardiomyopathy. The mechanisms include vasospasm of the coronary arteries and/or the microvasculature. This finding has been confirmed with molecular imaging with neurologic perfusion agents such as I-123 metaiodobenzyl-guanidine and I-123 metyliodopheny pentadecanoid acid. Although answer “A” is clearly a possibility, transmural ischemia due to embolization severe enough to cause this degree of ventricular dysfunction would result in more dramatic ECG and enzyme abnormalities, as would MI. Chest trauma could be ruled out by history and physical, and would not cause the specific abnormalities on the ventriculogram.

10: d Transient LV apical balloon, or Takotsubo cardiomyopathy, characteristically has an excellent prognosis, leading to complete recovery of LV function and normalization of the echocardiogram. The 2-dimensional echocardiogram would likely be entirely normal. Myocardial infarction very often leaves residual changes on the echocardiogram. Left ventricular aneurysm usually persists on follow-up studies.

WMJ

Guttormsen B, Nee L, Makielski JC, et al. Transient left ventricular apical ballooning: a review of the literature. . 2006;105(3):49-54.

Clin Cardiology

Elian D, Osherov A, Matetzky S, et al. Left ventricular apical ballooning: not an uncommon variant of acute myocardial infarction in women. . 2006;29(1):9-12.

Clin Cardiology

Conti CR. Four left ventricular apical abnormalities. . 2006;29(2):50-51.

Heart.

Connelly KA, MacIsaac AI, Jelineck VM. Stress, myocardial infarction and the “Tako-Tsubo” phenomenon. 2004;90(9):e52.

Mayo Clin Proc

Ibanez B, Benezet-Mazuecos J. Takotsubo syndrome: a Bayesian approach to interpreting its pathogenesis. . 2006;81(6):732-735.