Preparing for the American Board of Internal Medicine Maintenance of Certification

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

Questions 1-3 refer to the following clinical scenario.

A 57-year-old man presents to your office with intermittent palpitations. They last between 30 seconds and 10 minutes and have occurred several times per week over the past year. No associated symptoms (ie, dyspnea, chest pain, or diaphoresis) are present. His medical history is otherwise unremarkable and he takes no medications. His exam is remarkable only for a regular pulse. The electrocardiogram is essentially normal.

1. Appropriate investigation would include:

1. Stress test to evaluate for ischemia, echocardiogram for structural heart disease, chemistries including thyroid stimulating hormone (TSH), blood count, and Holter monitor.
2. Echocardiogram for structural heart disease, chemistries including TSH, complete blood count, and Holter monitor.
3. Implanted loop recorder if Holter is negative for tachyarrhythmias.
4. Holter monitor followed by event recorder if Holter is negative, followed by implanted loop recorder if event recorder is negative.
5. Tilt table test to evaluate for autonomic imbalance.

2. A 24-hour Holter monitor discloses one 30-second run of atrial fibrillation that was asymptomatic. Appropriate management would include:

1. Initiation of aspirin.
2. Initiation of warfarin.
3. Hospitalization for initiation of heparin simultaneously with warfarin, discharge upon international normalized ratio (INR) ≥ 2.0.
4. Initiation of aspirin and clopidogrel.
5. Initiation of outpatient enoxaparin, 1 mg/kg twice daily subcutaneously simultaneously with warfarin, stop enoxaparin when INR ≥ 2.0.

3. Echocardiography demonstrates essentially normal findings. Appropriate management would now include:

1. Sotalol or propafenone at starting doses, office electrocardiogram in 3-5 days, uptitrate as needed to eliminate palpitations provided QTc < 500 ms (sotalol) or QRS < 140 ms (propafenone).
2. Amiodarone, 200 mg twice daily for 2 weeks, then 200 mg daily for 3 months, then 100 mg daily if palpitations are eliminated.
3. ß blocker or rate-slowing calcium channel blocker in starting doses, uptitrate as needed to reduce or eliminate palpitations.
4. Digoxin, 0.25 mg daily.
5. Office discussion to review extent of symptoms, degree of impairment associated with palpitations, course of atrial fibrillation, and risks and benefits of rate control versus rhythm control strategies.

4. Which of the following statements is incorrect regarding peripartum cardiomyopathy?

1. Compared with other forms of dilated cardiomyopathy, myocarditis is more commonly encountered. Therefore, an endomyocardial biopsy is warranted, or a trial of steroids can be considered.
2. Recurrence rates in subsequent pregnancies may be 1/3 or more. Therefore, counseling regarding birth control and possible sterilizations is appropriate, though repeat pregnancy is not absolutely contraindicated.
3. ß blockers and angiotensin-converting enzyme (ACE) inhibitors are generally regarded as safe in lactating mothers, although ACE inhibitors are contraindicated during a subsequent pregnancy.
4. Prognosis at diagnosis is guarded, and the course may be variable.

5. Which statement is correct regarding patent foramen ovale (PFO)?

1. The incidence of PFO is increased in young patients with cryptogenic stroke. After investigation for possible heritable hypercoagulable states, warfarin should be initiated.
2. Percutaneous PFO closure should be undertaken when a significant right-to-left shunt is discovered on transthoracic echocardiography.
3. Patent foramen ovale can be detected in 40% of the asymptomatic adult population by echocardiogram and agitated saline contrast echocardiography.
4. Patients with confirmed migraine have a higher-than-expected incidence of PFO compared with the general population. Percutaneous PFO closure may reduce the frequency and duration of migraine, but should only be undertaken in the context of a randomized trial.
5. Detection of PFO at catheterization requires demonstration of right-to-left or left-to-right shunting by sequential oximetery ("saturation run").

Questions 6-10 refer to the following clinical scenario.

A 63-year-old woman with a history of hypothyroidism and hypertension is brought into the hospital emergency department by her family for the evaluation of mental status changes. The patient has been on antihypertensive medications, including metoprolol succinate 25 mg extended release (Toprol XL) daily and Lasix 40 mg PO twice a day. She is also taking thyroid supplements, but is not aware of the type of medication or dosage in this case. There is a strong suspicion that the patient has been noncompliant with prescribed medications.

On physical exam the patient's blood pressure is 128/64 mm Hg and her heart rate is 88 beats per minute (BPM). The patient is moderately obese (5'4", 210 lbs), appears lethargic but in no distress, and denies shortness of breath or chest pain. Physical exam demonstrates decreased breath sounds but no crackles. Sounds are distant but there are no murmurs or gallops. Her abdomen is slightly obese but not tender. There is bilateral trace edema on examination of the extremities.

Laboratory values include an elevated TSH level of 120 µ/dL. The white count is slightly elevated with a normal differential. The patient has normal oxygenation on room air. Electrocardiogram (ECG) reveals sinus rhythm and low QRS voltage (ie, < 0.7 mV in amplitude).

Echocardiography is ordered as part of the patients' workup. This study reveals moderate left ventricular dysfunction with an ejection fraction of 35%. There is a large circumferential pericardial effusion noted with a minimal degree of right-heart chamber compromise.

6. Based on the electrocardiography findings, the differential diagnosis for this patient could be:

1. Cardiomyopathy.
2. Pericardial effusion.
3. Hypothyroidism.
4. Obesity.
5. All of the above.

7. The echocardiographic findings of a pericardial effusion in this patient are most likely due to:

1. Viral infection.
2. Uremia.
3. Malignancy.
4. Myxedema.
5. The addition of erythropoietin.

The patient is admitted to the hospital and started on intravenous (IV) thyroid replacement. The next day, she is clinically unchanged. A cardiology consult is requested due to the echocardiographic findings.

8. Based on the findings of a large effusion with a minimal degree of right chamber collapse in a hemodynamically stable patient, pericardiocentesis would be required.

1. True.
2. False.

On the third hospital day the patient develops a low-grade temperature of 101.1°F. A physical exam reveals a slightly elevated respiratory rate of 23 breaths per minute. Repeat echocardiography is unchanged. The patient's heart rate now is 105 BPM and the blood pressure is 90/60 mm Hg.

9. Pericardiocentesis should be considered at this point.

1. True.
2. False.

The patient is sent for a pericardiocentesis on the 4th hospital day, and 1.5 liters of a yellowish colored fluid is removed successfully from the pericardial space. The drain is left overnight and removed only when drainage is less than 30 mL/24 hours. The patient's heart rate remains elevated at 110 BPM, but after treatment with IV vancomycin and ceftriaxone her heart rate normalizes. Repeat echocardiography is obtained 3 days later.

10. Findings on repeat echocardiography would likely include:

1. Re-accumulation of the pericardial effusion to its initial size.
2. Partial re-accumulation of the pericardial effusion to 50% of initial size.
3. Trivial pericardial effusion.
4. An increase in intensity during passive leg elevation.
5. Pericarditis.