Question 1

A 72-year-old man comes to the emergency department due to progressive shortness of breath and cough productive of yellowish sputum. The patient says, "I have been feeling breathless for the past several months while mowing the lawn or walking around the house, but it has been worse over the last 3 days." He has had no chest pain or leg swelling but notes that his heart "has been racing." The patient has a history of hypertension, peptic ulcer disease, and osteoarthritis. He was hospitalized for pneumonia a year ago and required intravenous antibiotics. Six months ago, the patient underwent a cardiac stress test for chest discomfort, which was unremarkable. The patient has smoked a pack of cigarettes daily for 45 years. Blood pressure is 160/90 mm Hg, pulse is 148/min, and respirations are 26/min. He is speaking in partial sentences and using accessory muscles of respiration but is alert and cooperative. There is no jugular venous distension or heart murmurs, rub, or gallops, but the heart sounds are irregular. Lung auscultation reveals bilateral rhonchi and expiratory wheezes. Arterial blood gases while breathing 2 L of oxygen via nasal cannula reveal PO₂ of 66 mm Hg, PCO₂ of 52 mm Hg, and pH 7.33. ECG shows narrow QRS complexes with distinct P waves of different morphologies and variable PR segments and R-R intervals. Chest x-ray reveals no pulmonary infiltrates or consolidation. Inhaled bronchodilators and systemic glucocorticoids are administered. Which of the following is the most appropriate additional step in management of this patient's arrhythmia?

Accepted Answer

Explanation: 11ec2b69_be3a_ae8d_8f63_1d62d1ef5c8b_MD0005_00 This patient's ECG findings are consistent with multifocal atrial tachycardia (MAT). MAT may result from atrial conduction abnormalities triggered by disturbances such as right atrial enlargement, catecholamine surge (eg, sepsis), or electrolyte imbalance. MAT is most commonly seen in elderly patients (eg, age >70) with an acute exacerbation of underlying pulmonary disease (eg, chronic obstructive pulmonary disease [COPD]). Patients typically present with symptoms of the underlying illness (eg, cough, wheezing, shortness of breath), and the tachycardia itself is usually asymptomatic (other than possible palpitations). Cardiac examination in patients with MAT should reveal an irregular rhythm with rapid rate. The diagnosis is confirmed by ECG showing distinct P waves of at least 3 different morphologies, irregular R-R intervals, and an atrial rate >100/min; the elevated atrial rate differentiates MAT from a diagnosis of wandering atrial pacemaker. The best treatment is appropriate management of the inciting illness; the administration of bronchodilators, systemic corticosteroids, and noninvasive ventilation (indicated due to respiratory distress with use of accessory muscles) for this patient's probable exacerbation of undiagnosed COPD can lead to resolution of the MAT. ECG (Choice A) Intravenous amiodarone is used for pharmacological cardioversion in patients with atrial fibrillation; however, it is not used in management of MAT. (Choices B and C) Intravenous nondihydropyridine calcium channel blockers (eg, verapamil, diltiazem) and beta blockers (eg, esmolol) can be used to control the rapid ventricular rate in patients with MAT. However, these medications do not address the underlying cause of MAT, and treatment of the inciting illness is the best initial management. (Choice E) Urgent synchronized cardioversion is appropriate for hemodynamically unstable supraventricular tachycardia; however, MAT rarely leads to hemodynamic instability. Management of the underlying COPD exacerbation is most appropriate in this patient with adequate blood pressure and organ perfusion. Educational objective: Multifocal atrial tachycardia most commonly occurs in elderly patients who are hospitalized with an exacerbation of underlying pulmonary disease (eg, chronic obstructive pulmonary disease). The diagnosis is made by ECG demonstrating P waves of at least 3 different morphologies and an atrial rate >100/min. Treatment involves appropriate management of the underlying inciting illness. References: Multifocal atrial tachycardia. (http://www.ncbi.nlm.nih.gov/pubmed/9440591) 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. (http://www.ncbi.nlm.nih.gov/pubmed/26399663)

Question 2

A 34-year-old woman comes to the office due to intermittent palpitations for 2 weeks. The patient has no chest pain or shortness of breath. She was diagnosed with hypertrophic cardiomyopathy 10 years ago and hypothyroidism 5 years ago. The patient takes metoprolol and levothyroxine. Temperature is 37.1 C (98.8 F), blood pressure is 120/80 mm Hg, pulse is 65/min and regular, and respirations are 15/min. BMI is 27 kg/m². Oxygen saturation is 98% on room air. Mucous membranes are moist. Jugular venous pressure is normal. The thyroid gland is symmetrically enlarged and nontender. The lungs are clear to auscultation. A grade 2/6 systolic murmur is heard best at the left sternal border. Complete blood count and serum chemistries are normal. Serum TSH concentration is 1.4 μU/mL. ECG shows normal sinus rhythm with T-wave inversions in the anterior leads, unchanged from 6 months ago. Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_be32_e651_8f63_ebc6af82fd2b_MD0005_00 Patients with hypertrophic cardiomyopathy (HCM) are at increased risk for cardiac arrhythmia, namely the following: Atrial fibrillation: The increased risk in HCM likely results from left ventricular diastolic dysfunction leading to left atrial enlargement, creating a substrate for atrial fibrillation. Thromboembolic stroke related to atrial fibrillation is an important cause of morbidity and mortality in patients with HCM. Ventricular tachycardia: The increased risk in HCM is related to myocardial disarray and fibrosis, as well as chronic myocardial ischemia resulting from myocardial oxygen supply-demand mismatch. Sustained ventricular tachycardia is the typical cause of sudden cardiac arrest, the most common cause of mortality in HCM. Periodic ambulatory ECG monitoring (eg, 24-hr Holter monitoring) is indicated in patients with HCM so that arrhythmic complications can be promptly recognized. This monitoring is especially important in those with symptoms suggestive of paroxysmal arrhythmia, as in this patient with palpitations. Evidence of atrial fibrillation on ECG monitoring warrants the initiation of chronic anticoagulation, and evidence of ventricular tachycardia (eg, bursts of nonsustained ventricular tachycardia) may warrant placement of an implantable cardioverter defibrillator. (Choice A) Adding verapamil to metoprolol for additional negative chronotropy and inotropy can be appropriate in HCM patients with persistent exertional symptoms (eg, dyspnea, chest pain) thought to be due to left ventricular outflow tract obstruction. However, palpitations are more suggestive of cardiac arrhythmia that needs to be investigated. (Choice C) Coronary angiography is of minimal use in relatively young patients with HCM as most have normal epicardial coronary arteries. The coronary microvascular dysfunction that is common with HCM and contributes to myocardial ischemia is not detectable (or treatable) via coronary angiography. (Choice D) CT pulmonary angiography is used to diagnose acute pulmonary embolism, which is unlikely in this patient with no shortness of breath and normal oxygen saturation. (Choice E) Serum free thyroxine (T4) concentration can help assess the degree of hyperthyroidism or hypothyroidism when the TSH level is abnormal. However, because a normal TSH level is accurately representative of normal T4 levels, free T4 concentration is of little use when the TSH level is normal, as in this patient. Educational objective: Patients with hypertrophic cardiomyopathy are at increased risk for atrial fibrillation and ventricular tachycardia. Periodic ambulatory ECG monitoring is indicated to facilitate prompt recognition and management of these arrhythmias, especially in patients with suggestive symptoms (eg, palpitations). References: Atrial fibrillation in hypertrophic cardiomyopathy: a turning point towards increased morbidity and mortality. (http://www.ncbi.nlm.nih.gov/pubmed/28219794)

Question 3

A 44-year-old man comes to the office due to progressive shortness of breath over the last 6 months. The patient says that lately he has been unable to walk even 2 blocks without stopping to rest. He finds this very unusual as one year ago he used to jog for 2 miles almost daily with no symptoms. The patient reports no chronic health problems and takes no medications. He is a lifetime nonsmoker and does not drink alcohol or use illicit drugs. The patient has no family history of premature cardiovascular disease or sudden cardiac death. Blood pressure is 138/80 mm Hg and pulse is 85/min and regular. BMI is 30 kg/m². Lungs are clear on auscultation. The point of maximal impulse is displaced to the left. There is normal splitting of S2 with presence of S3. A 3/6 holosystolic murmur is heard at the apex following a click. There are no carotid bruits. There is trace peripheral edema. Transthoracic echocardiogram is performed, which shows left ventricular and left atrial dilation. There is a flail segment of the posterior mitral leaflet with severe eccentric mitral regurgitation. Left ventricular ejection fraction is 55%. There are no other significant valvular abnormalities. Which of the following best describes this patient's condition?

Accepted Answer

Explanation: This patient has chronic primary mitral valve regurgitation (MR) with impaired left ventricular systolic function. Primary MR is defined as that caused by an intrinsic defect of the mitral valve apparatus (eg, leaflets, chordae tendineae); myxomatous degeneration of the mitral valve leading to mitral valve prolapse (evidenced by a systolic click in this patient) is one of the most common causes of chronic primary MR. Chronic MR is classified as severe in the presence of associated symptoms (eg, dyspnea on exertion, heart failure) or specific echocardiogram findings (eg, left atrial and left ventricular [LV] enlargement, regurgitant jet prominence). In patients with severe MR, a large portion of the left ventricular ejection fraction (LVEF) flows back into the left atrium; therefore, the effective LVEF is much lower than estimated by echocardiogram. As a result, patients with severe chronic primary MR and LVEF <60% are considered to have impaired LV systolic function, and mitral valve repair or replacement is typically indicated. (Choice A) Acute MR occurs due to rupture of a chordae tendineae or papillary muscle, most often in the setting of acute myocardial infarction. The left atrium and left ventricle do not have time to dilate and compensate for the sudden increase in LV preload, and so patients typically present with acute and rapidly progressive pulmonary edema, hemodynamic collapse, and cardiogenic shock. This patient's gradual presentation is not consistent with acute MR. (Choice C) LVEF >50% is considered normal in most patients; however, in patients with severe, chronic primary MR, LVEF <60% is consistent with abnormal LV systolic function.(Choices D and E) Secondary (or functional) MR refers to that occurring due to a disease process involving the left ventricle (eg, myocardial ischemia, dilated cardiomyopathy). The mitral valve is usually intrinsically normal, and so the management of secondary MR mainly involves optimizing LV function (eg, medication, cardiac resynchronization therapy) rather than mitral valve surgery. Educational objective: Chronic primary mitral valve regurgitation (MR) is defined as mitral valve insufficiency that results from an intrinsic defect of the mitral valve apparatus (eg, leaflets, chordae tendineae). Patients with severe, chronic primary MR and left ventricular (LV) ejection fraction <60% are considered to have impaired LV systolic function, and mitral valve surgery is typically indicated. References: Mitral regurgitation: current trends in diagnosis and management. (http://www.ncbi.nlm.nih.gov/pubmed/21441774) Impact of echocardiography on indications for surgery in chronic mitral and aortic regurgitation. (http://www.ncbi.nlm.nih.gov/pubmed/15346838)

Question 4

A 70-year-old woman is brought to the emergency department by her son for evaluation of shortness of breath. She has had a sensation of choking since last night. According to her son, for the past several weeks she has had a dry cough at night and has been taking over-the-counter cough drops. The patient has had no chest pain, palpitations, back pain, abdominal symptoms, or lightheadedness. She has a history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. She has been refusing statin therapy, as she heard statins cause multiple side effects. The patient has also refused flu vaccinations over the last several years. Her only hospital admission occurred 6 years ago when she underwent a spinal fusion for lower back pain. She does not use tobacco, alcohol, or illicit drugs. Family history is not significant. Temperature is 36.1 C (97 F), blood pressure is 171/102 mm Hg, pulse is 92/min, and respirations are 34/min. Pulse oximetry is 85% on room air. BMI is 29 kg/m². Bilateral crackles are heard on lung examination. There are no heart murmurs. ECG shows normal sinus rhythm, increased voltage in the precordial leads, and T-wave inversion in leads V5 and V6. Chest x-ray is shown in the exhibit. Oxygen is administered via 100% nonrebreather facemask. The patient is placed on noninvasive positive pressure ventilation but still appears somewhat uncomfortable. Laboratory results are as follows: The first troponin I level is negative. Repeat blood pressure is 176/105 mm Hg, pulse is 82/min, and respirations are 24/min. Oxygen saturation is 94%. What is the best next step in management of this patient?

Accepted Answer

Explanation: The addition of an intravenous vasodilator is recommended in patients with acute decompensated heart failure (ADHF) who have an inadequate response to initial diuretic therapy. Nitroglycerin is most commonly used; as primarily a venous dilator, it leads to a rapid decrease in cardiac preload, resulting in reduced intracardiac filling pressures and improvement in pulmonary edema. Nitroprusside is less commonly used due to the risk of adverse effects (eg, cyanide toxicity, severe hypotension); it decreases intracardiac filling pressures through balanced vasodilation and reductions in both cardiac preload and afterload. Because intravenous vasodilator therapy often results in rapid improvement of acutely symptomatic pulmonary edema, it is indicated right away (prior to or instead of intravenous diuretics) in patients with "flash" pulmonary edema due to severe hypertension (>180/120 mm Hg) (ie, hypertensive emergency). (Choice A) Digoxin is a positive inotropic agent used in some patients with chronic heart failure due to left ventricular (LV) systolic dysfunction. However, it has no role in the management of ADHF. (Choice B) Pulmonary edema due to atrial fibrillation with rapid ventricular response is one ADHF scenario where metoprolol may actually provide benefit (by increasing markedly low ventricular filling times); however, in this patient with normal heart rate and sinus rhythm on ECG, metoprolol is likely to worsen pulmonary edema. (Choice C) Milrinone is a selective phosphodiesterase-3 inhibitor that causes positive inotropy as well as reductions in preload and afterload. It can be useful for ADHF due to LV systolic dysfunction; however, it is associated with increased risk of hypotension and atrial or ventricular arrhythmia, and is typically reserved for severe ADHF that is refractory to other management. (Choice E) Intravenous unfractionated heparin is indicated for acute myocardial infarction, which can lead to ADHF. However, there is currently no evidence of acute myocardial infarction in this patient with no chest pain, no ST elevation on ECG, and a negative initial serum troponin. Educational objective: Intravenous vasodilators (eg, nitroglycerin) reduce intracardiac filling pressures and are recommended in patients with acute decompensated heart failure who have an inadequate response to initial diuretic therapy. In addition, they are indicated as initial therapy (prior to or instead of intravenous diuretics) in patients with "flash" pulmonary edema due to severe hypertension. References: 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/23741058) HFSA 2010 comprehensive heart failure practice guideline. (http://www.ncbi.nlm.nih.gov/pubmed/20610207)

Question 5

A 52-year-old woman comes to the emergency department with left leg pain and swelling. She is a commercial truck driver and first noticed the swelling 3 days ago. The patient initially attributed the swelling to a long haul truck ride as she often gets mild "puffiness" of her ankles by the end of the day. However, the swelling has persisted and now involves her entire left leg below the knee. She has discomfort with walking but no chest pain, palpitations, syncope, or difficulty breathing. The patient has a history of hypothyroidism and hypertension and takes levothyroxine and hydrochlorothiazide. She has also been on menopausal hormone therapy using estrogen-progestin for intractable hot flashes. She smokes a pack of cigarettes daily and drinks 2 beers each night. Temperature is 37.2 C (99 F), blood pressure is 134/89 mm Hg, and pulse is 78/min. BMI is 31 kg/m². Extremity examination reveals a normal right leg and pitting edema and warmth over the left lower leg. ECG shows normal sinus rhythm, and chest x-ray is normal with no infiltrates. Serum creatinine level is 0.7 mg/dL. Duplex ultrasound of the lower extremities reveals noncompressibility of the left popliteal and femoral veins. The patient is started on rivaroxaban and scheduled to follow up with her primary care physician. She is counseled on smoking cessation and agrees to enroll in a smoking cessation clinic. The patient is also informed that her current menopausal hormone therapy (MHT) increases her risk of venous thromboembolism. She is concerned about experiencing hot flashes again. Which of the following is the most appropriate recommendation for treatment of this patient's menopausal symptoms?

Accepted Answer

Explanation: Hot flashes occur in >80% of women in the perimenopausal and early menopausal period. Manifestations largely arise due to estrogen withdrawal, and treatment with menopausal hormone therapy (MHT) can palliate symptoms significantly. Although healthy patients who receive MHT in the decade following menopause are at minimal risk for adverse outcomes, the rates of stroke, breast cancer, and venous thromboembolism (VTE) are mildly increased. The development of VTE while on MHT usually necessitates a cessation of hormone therapy as the benefit of continued treatment does not outweigh the risk of recurrent, potentially life-threatening VTE. The most common alternate treatments are selective serotonin reuptake inhibitors (SSRIs) (eg, escitalopram) or serotonin-norepinephrine reuptake inhibitors (eg, venlafaxine). Although the exact mechanism for how these medications improve hot flashes is currently unknown, 50%-70% of women who receive this therapy have a reduction in symptoms. (Choice A) SSRIs are not typically associated with an increased risk of deep venous thrombosis (DVT) and are a safe alternate therapy for those who develop DVT while on MHT. (Choice B) MHT should be discontinued, and this patient should receive 3-6 months of anticoagulation. Patients rarely need lifelong anticoagulation unless they have recurrent DVT or malignancy. (Choice D) Raloxifene is a breast cancer treatment for post-menopausal women due to estrogenic effects on bones and anti-estrogenic effects on the breasts and uterus. Raloxifene may increase (not decrease) the risk of hot flashes and is associated with an increased risk of VTE. (Choice E) Estrogen-only MHT also increases DVT risk and should not be used as a substitute in those who develop DVT while on combination (estrogen plus progestin) MHT. Educational objective: Patients who develop venous thrombosis while on menopausal hormone therapy (MHT) should discontinue MHT and begin an alternate treatment such as a selective serotonin reuptake inhibitor or a serotonin-norepinephrine reuptake inhibitor. References: Nonhormonal management of menopause-associated vasomotor symptoms: 2015 position statement of The North American Menopause Society (http://www.ncbi.nlm.nih.gov/pubmed/26382310)

Question 6

A 72-year-old man is brought to the emergency department after an episode of syncope during a family gathering.  The patient was sitting in his chair after dinner and passed out briefly.  There are no apparent injuries and no seizure-like activity was observed.  His granddaughter says that he has had frequent episodes of dizziness in the last 2 weeks.  These episodes are sometimes accompanied by confusion and are not related to physical activity or changes in position.  The patient's other medical problems include coronary artery disease and hypertension.  He does not use alcohol or tobacco.  His medications include aspirin, lisinopril, atorvastatin, and isosorbide mononitrate.  Blood pressure is 105/60 mm Hg and respirations are 14/min.  The patient is fully alert and oriented.  Examination reveals no neck bruits.  Lung fields are clear, and no cardiac murmurs are heard.  Neurologic examination is within normal limits.  ECG is shown in the exhibit.  Serum potassium is 4.1 mEq/L and serum creatinine is 1.1 mg/dL.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: This patient has bradycardia due to Mobitz type II second-degree atrioventricular (AV) block. Ischemia, electrolyte abnormalities, medications (eg, beta blockers, nondihydropyridine calcium channel blockers), infiltrative disease (eg, sarcoidosis), or age-related fibrosis can lead to impaired electrical conduction across the AV node. Patients may be asymptomatic or may have symptoms of poor cardiac output (eg, dyspnea, lightheadedness, syncope). The diagnosis of Mobitz type II AV block is made by ECG showing intermittent nonconducted P waves and a regular PR interval; it differs from Mobitz type I AV block, which shows nonconducted P waves following progressive elongation of the PR interval. ECG Unlike Mobitz type I AV block (usually asymptomatic and benign), Mobitz type II AV block has a high rate of progression to complete (third-degree) AV block and potentially devastating outcomes (eg, sudden cardiac death). Therefore, in the absence of a reversible cause (eg, pharmacologic AV nodal blockade, hyperkalemia, myocardial ischemia), Mobitz type II AV block necessitates the placement of a permanent pacemaker. (Choice B) This patient's ECG is diagnostic for Mobitz type II AV block. Although he should be closely monitored for progression to complete heart block until a pacemaker is placed, further diagnostic testing of his heart rhythm will not change the need for a pacemaker. (Choice C) Per advanced cardiac life support protocol, unstable patients (eg, those with hypotension, confusion, or chest pain) with Mobitz type II AV block or another bradycardia should be treated with intravenous atropine (0.5 mg every 3-5 minutes). However, atropine can sometimes worsen bradycardia due to Mobitz type II AV block and is not recommended in stable patients such as this one. (Choices D and E) Because Mobitz type II AV block often progresses to potentially fatal (complete) AV block, stress testing should not be performed without a pacemaker in place. If there is high suspicion for ischemia as a reversible cause, a temporary, rather than a permanent, pacemaker can be inserted prior to testing. Lack of chronotropic competence (an appropriate increase in heart rate with exertion) is expected in patients with advanced AV block, so testing for it is generally not useful. Educational objective: Mobitz type II second-degree atrioventricular block has a high rate of progression to complete (third-degree) atrioventricular block. In the absence of a reversible cause, all patients should undergo permanent pacemaker implantation. References: Second-degree atrioventricular block revisited. (http://www.ncbi.nlm.nih.gov/pubmed/23224264)

Question 7

An 8-year-old girl is brought to the emergency department by her mother for evaluation of blurry vision.  The patient reports that she woke up this morning with a sudden onset of blurry vision.  Her mother states, "She has worn thick glasses since age 2, but this morning she said that everything was blurry in her left eye, even with her glasses on."  There is no associated erythema or discharge.  The patient does not recall any trauma.  The girl has no chronic medical conditions and has had no surgeries.  She is an honor roll student in the 3rd grade.  The patient lives with her mother, and her father left when she was an infant.  The mother's medical history is unremarkable but she says, "I think her father had a similar problem when he was younger and had a weak heart."  The patient is at the 50th and >95th percentiles for weight and height, respectively.  She is alert and in no distress.  The right pupil is 4 mm and briskly reactive; the left pupil is 1 mm.  Bilateral globes appear intact with no conjunctival injection.  Extraocular eye movements are intact bilaterally and visual fields are full to confrontation bilaterally.  A dilated direct ophthalmoscopic examination followed by a slit-lamp examination of the left eye reveals the following:  Which of the following conditions is this patient at greatest risk of developing?

Accepted Answer

Explanation: 11ec2b69_be37_2c19_8f63_9d8886e63684_MD0005_00 Marfan syndrome (MFS) is an autosomal dominant condition due to a defect in the connective tissue glycoprotein fibrillin-1. Fibrillin-1 is found throughout the musculoskeletal and cardiovascular systems (eg, aorta, heart valves) as well as in the zonular fibers that suspend the ocular lens in place. Lens subluxation or dislocation (ectopia lentis) occurs due to failure of these fibers to support the lens. Ectopia lentis, particularly in the superotemporal direction, is a hallmark feature of MFS. This finding on slit-lamp examination in a child with minimal to no preceding trauma is concerning for MFS as an underlying etiology. The most concerning comorbidity of MFS is aortic root disease. Aortic root dilation occurs in the majority of patients with MFS and can lead to life-threatening aortic dissection; therefore, echocardiography is performed at the time of diagnosis and annually to monitor progression. A beta blocker is typically prescribed to decrease myocardial contractility and to reduce the stress on the aortic wall. In addition, if the aortic root diameter is significantly or rapidly enlarging, surgical replacement may be considered to reduce the risk of aortic dissection or rupture. (Choice B) Berry aneurysms occur in patients with Ehlers-Danlos syndrome (EDS) due to increased fragility of the cerebral artery walls. EDS causes joint hypermobility and skin hyperextensibility, features not present in this patient. (Choice C) Gigantism is typically due to a growth hormone-secreting pituitary adenoma. Growth hormone hypersecretion causes tall stature and often results in glucose resistance due to impaired insulin signaling. Typical findings include coarse facial features and frontal bossing, not seen in this patient. In addition, bitemporal hemianopsia may occur from the pituitary adenoma compressing the optic chiasm, not ectopia lentis. bitemporal hemianopsia (Choice D) Retinoblastoma is a common childhood eye cancer that presents with leukocoria and a white, fluffy intraocular mass on ophthalmologic examination. It is not a complication of ectopic lens or MFS. leukocoria (Choice E) Homocystinuria is an autosomal recessive disorder with features similar to MFS (eg, Marfanoid habitus, myopia, ectopia lentis). However, venous thromboembolism and intellectual disability are unique findings absent in this child. Also, the lens classically displaces downward in homocystinuria versus upward in MFS. Educational objective: Patients with a nontraumatic ectopia lentis should be evaluated for Marfan syndrome, an autosomal dominant condition with an increased risk for aortic root disease (eg, dilation, dissection). References: Ectopia lentis as the presenting and primary feature in Marfan syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/21932315) Health supervision for children with Marfan syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/24081994)

Question 8

A 55-year-old woman comes to the office for a preventive visit.  She has no concerns at this time.  The patient experienced a myocardial infarction 2 years ago.  Current medications are metoprolol and aspirin.  The patient does not smoke or use alcohol.  Blood pressure is 125/80 mm Hg and pulse is 65/min.  Physical examination is unremarkable.  Fasting blood glucose level is 100 mg/dL.  Laboratory results are as follows:  The initiation of which of the following medications is most appropriate in this patient?

Accepted Answer

Explanation: 11ec2b69_be30_282f_8f63_c73fc98c1a73_MD0005_00 This patient has established atherosclerotic cardiovascular disease (ASCVD) based on her previous myocardial infarction. Patients with known ASCVD are at high risk for future cardiovascular events and death. Several randomized trials for secondary prevention of ASCVD have shown significant risk reduction in cardiovascular events and overall cardiovascular disease mortality in patients treated with statins. Current guidelines recommend high-intensity statin therapy (eg, atorvastatin 40-80 mg, rosuvastatin 20-40 mg daily) for secondary prevention in all patients age ≤75 with known ASCVD (moderate-intensity statin therapy is recommended for those age >75), regardless of baseline LDL level. Statin therapy is also recommended for primary prevention of ASCVD in patients with serum LDL ≥190 mg/dL, age ≥40 with diabetes mellitus, or with an estimated 10-year risk of ASCVD >7.5%-10% (guidelines vary on the exact cutoff) using the Pooled Cohort Equations risk calculator. risk calculator (Choice B) Bile acid sequestrants (eg, cholestyramine, colestipol, colesevelam) are effective in reducing LDL levels, but there is limited evidence of improvement in cardiovascular outcomes. (Choice C) Estrogen replacement therapy (eg, estradiol) has favorable effects on lipid levels (ie, reduced LDL, increased HDL) but does not lead to a lower risk of cardiovascular events. Estrogen replacement may actually increase cardiovascular risk in older, postmenopausal women (eg, age >60). (Choice D) Fibrates (eg, gemfibrozil) are the most effective pharmacologic therapy available for reducing triglyceride levels and are recommended in patients with severe hypertriglyceridemia (ie, >1000 mg/dL) to reduce the risk of pancreatitis. However, due to superior evidence of overall cardiovascular benefit, statins are the recommended first-line therapy for both secondary and primary prevention of ASCVD in patients with mild hypertriglyceridemia (ie, 150-500 mg/dL). hypertriglyceridemia (Choice E) Niacin (ie, nicotinic acid) is effective in increasing HDL levels and has modest effects in reducing LDL levels. However, despite the favorable effects on lipid profile, niacin has not shown improvement in cardiovascular outcomes in patients with known ASCVD. Educational objective: Statin therapy is recommended for all patients with established atherosclerotic cardiovascular disease, regardless of baseline LDL level. Therapy with nonstatin lipid-lowering medications has not been shown to improve cardiovascular outcomes and is not usually recommended. References: 2019 ACC/AHA guideline on the primary prevention of cardiovascular disease: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/30879355) Effects of extended-release niacin with laropriprant in high-risk patients. (http://www.ncbi.nlm.nih.gov/pubmed/25014686)

Question 9

A 72-year-old man comes to the emergency department due to progressive shortness of breath and cough productive of yellowish sputum. The patient says, "I have been feeling breathless for the past several months while mowing the lawn or walking around the house, but it has been worse over the last 3 days." He has had no chest pain or leg swelling but notes that his heart "has been racing." The patient has a history of hypertension, peptic ulcer disease, and osteoarthritis. He was hospitalized for pneumonia a year ago and required intravenous antibiotics. Six months ago, the patient underwent a cardiac stress test for chest discomfort, which was unremarkable. The patient has smoked a pack of cigarettes daily for 45 years. Blood pressure is 160/90 mm Hg, pulse is 148/min, and respirations are 26/min. He is speaking in partial sentences and using accessory muscles of respiration but is alert and cooperative. There is no jugular venous distension or heart murmurs, rub, or gallops, but the heart sounds are irregular. Lung auscultation reveals bilateral rhonchi and expiratory wheezes. Arterial blood gases while breathing 2 L of oxygen via nasal cannula reveal PO₂ of 66 mm Hg, PCO₂ of 52 mm Hg, and pH 7.33. ECG shows narrow QRS complexes with distinct P waves of different morphologies and variable PR segments and R-R intervals. Chest x-ray reveals no pulmonary infiltrates or consolidation. Inhaled bronchodilators and systemic glucocorticoids are administered. The patient's dyspnea has improved after initial treatment in the emergency department, but he continues to have palpitations. Pulse is 125/min and irregular. Blood pressure is 140/88 mm Hg and respirations are 16/min. Oxygen saturation is 92% on 2 L oxygen via nasal cannula. ECG findings are unchanged from the time of admission. Laboratory results are as follows: Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: This patient has persistent multifocal atrial tachycardia (MAT) following initial treatment and improvement of his exacerbation of chronic obstructive pulmonary disease. Electrolyte disturbances (eg, hypokalemia, hypomagnesemia) are a common cause of MAT; therefore, laboratory results show another underlying disturbance that should be addressed. The next step in managing this patient's MAT should be adequate potassium replacement; further history should be collected as well to elucidate the cause of his hypokalemia (eg, diarrhea, diuretic use). Preferably, serum potassium should be replaced to a level of 4.0 mEq/L, and serum magnesium should be maintained at (or replaced to) a level of 2.0 mEq/L. Repletion of depleted electrolytes will often lead to conversion to sinus rhythm in patients with MAT. (Choice A) This patient's hyponatremia is likely due to poor oral intake and intravascular volume depletion in the setting of a recent upper respiratory illness. Gentle rehydration will likely correct the hyponatremia. Hypertonic saline is reserved for severe, symptomatic hyponatremia (eg, seizures, profound confusion). (Choices B and C) Intravenous beta blockers (eg, esmolol) and nondihydropyridine calcium channel blockers (eg, verapamil) slow conduction of the atrioventricular node and can be used to control the rapid ventricular rate of MAT. However, these drugs should not be initiated until the potentially correctable causes of MAT have been adequately addressed. (Choice E) Anticoagulation (eg, unfractionated heparin) is indicated in patients with atrial flutter or atrial fibrillation to lower the risk of systemic thromboembolism. However, patients with MAT do not have an increased risk of left atrial thrombus formation, and anticoagulation is not indicated. Educational objective: The initial management of multifocal atrial tachycardia (MAT) is directed toward correction of underlying disturbances (eg, exacerbation of pulmonary disease, hypokalemia). Calcium channel blockers or beta blockers can be used for rate control in patients for whom MAT persists despite correction of potential underlying causes. References: 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. (http://www.ncbi.nlm.nih.gov/pubmed/26399663) Magnesium and potassium therapy in multifocal atrial tachycardia. (http://www.ncbi.nlm.nih.gov/pubmed/4050650)

Question 10

A 28-year-old woman comes to the office due to exertional shortness of breath for the last 2 weeks. She and her husband recently immigrated to the United States from Cambodia. She has a history of rheumatic mitral stenosis with an estimated mitral valve area of 1.5 cm², which was documented on her most recent transthoracic echocardiogram 4 months ago. The patient's exercise tolerance is about 5 blocks of brisk walking at baseline but is currently about 1 block. She has had no recent upper respiratory infection, sore throat, cough, orthopnea, lower extremity swelling, palpitations, syncope, or chest pain. Blood pressure is 108/67 mm Hg, and pulse is 92/min and regular. A diastolic rumble is heard at the apex in the left decubitus position. The lungs are clear on auscultation. Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_be3a_124c_8f63_cd83f1929c85_MD0005_00 This patient has known rheumatic heart disease with severe mitral stenosis, defined as a mitral valve area ≤1.5 cm² (normal: 4-6). Patients with mitral stenosis can remain asymptomatic for years and typically experience a gradual onset of symptoms. Dyspnea is often the first manifestation, followed by cough and hemoptysis (due to pulmonary edema) as well as symptoms of right-sided heart failure (eg, peripheral edema, hepatomegaly). Increased cardiovascular demand can hasten symptom development in patients with mitral stenosis. The normal physiologic changes of pregnancy include increases in plasma volume, heart rate, and cardiac output, which cause an increased flow gradient across the mitral valve (evidenced by a prominent diastolic murmur at the apex). This can lead to worsening symptoms in previously stable patients with mitral stenosis. This patient has experienced a relatively abrupt worsening of dyspnea on exertion and should be evaluated for pregnancy as the precipitating cause. (Choice A) Chest x-ray in mitral stenosis may show signs of left atrial enlargement (eg, straightened left heart border, left bronchus elevation); however, these findings are neither sensitive nor specific. Chest x-ray is useful to evaluate volume overload in patients with mitral stenosis but is unlikely to be helpful in this patient with no signs of pulmonary edema. (Choice B) Pulmonary function testing is helpful in diagnosing obstructive (eg, asthma) or restrictive lung disease (eg, interstitial lung disease). However, these conditions are a less likely cause of dyspnea on exertion in this patient with clear lungs and known severe mitral stenosis. (Choice C) Measurement of serum creatinine and electrolytes is indicated when acute renal failure is suspected. Although acute renal failure can present with dyspnea, the dyspnea is usually associated with signs of volume overload (eg, jugular venous distension, pulmonary crackles, peripheral edema). (Choice D) Transesophageal echocardiogram is often performed to confirm severity and to evaluate the subvalvular apparatus in patients with mitral stenosis. However, it is invasive and not needed to evaluate the most likely underlying cause of this patient's worsening dyspnea. Educational objective: The physiologic changes of pregnancy (eg, increased plasma volume and heart rate) cause an increase in flow gradient across the mitral valve, and can lead to worsening symptoms in previously stable patients with mitral stenosis. References: 2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/24603191)

Question 11

A 70-year-old woman is brought to the emergency department by her son for evaluation of shortness of breath. She has had a sensation of choking since last night. According to her son, for the past several weeks she has had a dry cough at night and has been taking over-the-counter cough drops. The patient has had no chest pain, palpitations, back pain, abdominal symptoms, or lightheadedness. She has a history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. She has been refusing statin therapy, as she heard statins cause multiple side effects. The patient has also refused flu vaccinations over the last several years. Her only hospital admission occurred 6 years ago when she underwent a spinal fusion for lower back pain. She does not use tobacco, alcohol, or illicit drugs. Family history is not significant. Temperature is 36.1 C (97 F), blood pressure is 171/102 mm Hg, pulse is 92/min, and respirations are 34/min. Pulse oximetry is 85% on room air. BMI is 29 kg/m². Bilateral crackles are heard on lung examination. There are no heart murmurs. ECG shows normal sinus rhythm, increased voltage in the precordial leads, and T-wave inversion in leads V5 and V6. Chest x-ray is shown in the exhibit. Oxygen is administered via 100% nonrebreather facemask. Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Acute decompensated heart failure (ADHF) results from a critical elevation in intracardiac filling pressures that most commonly occurs due to left ventricular (LV) systolic and/or diastolic dysfunction (eg, coronary ischemia, hypertensive cardiomyopathy). Other causes include valvular disease and marked elevations in preload (eg, excessive volume resuscitation) or afterload (eg, severe hypertension). This patient with chronic hypertension, possible medication nonadherence (eg, refusing statins and vaccinations), ECG evidence of LV hypertrophy (ie, increased voltage in the precordial leads), and several weeks of cough likely has chronic LV dysfunction due to hypertension. She has experienced gradually increasing LV filling pressures that reached a critical point, resulting in ADHF and pulmonary edema (bilateral crackles, vascular congestion on chest x-ray, tachypnea, hypoxia). Jugular venous distension is usually present but lower extremity edema may be absent, especially in patients without chronic heart failure. Early therapeutic goals include hemodynamic stabilization, improved oxygenation (ie, with supplemental oxygen or positive pressure ventilation), and optimization of volume status. Intravenous diuretics (eg, furosemide) are an important part of initial therapy as they reduce intravascular volume, lower intracardiac filling pressures, and improve pulmonary edema. (Choice A) This patient is without fever, purulent sputum production, or focal consolidation on chest x-ray to suggest respiratory failure due to pulmonary infection; intravenous antibiotics are not indicated. (Choice C) Glucocorticoids (eg, methylprednisolone) are indicated for an exacerbation of chronic obstructive pulmonary disease; however, this patient's bilateral crackles on lung examination, evidence of pulmonary edema on chest x-ray, and lack of tobacco use make ADHF more likely. (Choice D) Beta blockers (eg, metoprolol) are important in the management of chronic heart failure due to LV systolic dysfunction. They are also used in certain patients with tachyarrhythmias or ST-elevation myocardial infarction. However, they are usually contraindicated in ADHF due to the negative inotropy and chronotropy causing a potential worsening of pulmonary edema. (Choice E) Intravenous thrombolytic (eg, alteplase) therapy is indicated in patients with hypotension (ie, systolic blood pressure <90 mm Hg) or shock due to acute pulmonary embolism. This patient is not hypotensive and the several weeks of cough, marked pulmonary edema on chest x-ray, and absence of chest pain make ADHF more likely. Educational objective: Acute decompensated heart failure results from a critical elevation in intracardiac filling pressures, often due to left ventricular dysfunction, and leads to pulmonary edema. Intravenous diuretics (eg, furosemide) lower intracardiac filling pressures and improve pulmonary edema, and are an important part of initial therapy. References: HFSA 2010 comprehensive heart failure practice guideline. (http://www.ncbi.nlm.nih.gov/pubmed/20610207) 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/23741058)

Question 12

A 31-year-old man comes to the physician due to exertional shortness of breath over the last year. He gets short of breath after running 1-2 miles but feels mostly fine with daily activities. He has no chest pain, palpitations, or fainting spells. He also has no past medical history and takes no medications. There is no family history of sudden death. His blood pressure is 147/90 mm Hg, pulse is 77/min, and body mass index is 22 kg/m². The apical precordial impulse is hyperdynamic. S1 and S2 are normal and a fourth heart sound is heard. He has a 2/6 systolic murmur at the left sternal border which increases with Valsalva. The lungs are clear to auscultation. An echocardiogram shows interventricular septal thickness of 1.8 cm (normal <1.1 cm) and posterior left ventricular wall thickness of 0.9 cm (normal <1.1 cm). Left ventricular ejection fraction is 75%. There is systolic anterior motion of the mitral valve. At rest, his peak instantaneous left ventricular outflow gradient is 25 mm Hg; however, it is 65 mm Hg after exercise. Holter monitoring for 24 hours shows no abnormalities. Which of the following is the best next step in the management of this patient?

Accepted Answer

Explanation: This patient's clinical presentation - fatigue, exertional dyspnea, systolic murmur that accentuates with Valsalva, asymmetric septal hypertrophy, systolic anterior motion (SAM) of mitral leaflets, and increased left ventricular outflow tract (LVOT) gradient - is consistent with hypertrophic cardiomyopathy (HCM). HCM is an autosomal dominant genetic disorder of the cardiac sarcomere. It has a heterogeneous and variable clinical presentation depending on the degree of hypertrophy and LVOT obstruction. Patients with HCM may have no symptoms or have severe symptoms of fatigue, dyspnea, chest pain, palpitations, presyncope, or syncope. systolic murmur Patients with symptoms of heart failure and increased LVOT gradient should be treated with negative inotropic agents (beta-blockers, verapamil or disopyramide) as the initial medical therapy. Beta-blockers are the most commonly used agents for initial monotherapy; verapamil or disopyramide can be added to beta-blocker therapy in patients with persistent symptoms. (Choice A) Alcohol septal ablation involves injecting ethanol into the first or second septal perforator artery to cause a localized myocardial infarction in the basal septum. This causes localized scarring and remodeling over time and can lead to a reduction in LVOT gradient with improvement in symptoms and exercise capacity. It is usually reserved for patients with persistent symptoms that are refractory to medical therapy. (Choice B) Amiodarone is not routinely used in the management of patients with HCM. It can be used as an adjunctive therapy in patients who are at risk for sudden cardiac death and are not candidates for implantable cardioverter-defibrillator (ICD), or in patients with ICD who experience frequent arrhythmias. (Choice C) Vasodilators (dihydropyridine calcium channel blockers such as amlodipine and nifedipine), angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers, and nitrates can reduce systemic vascular resistance with worsening of the LVOT gradient and symptoms. These should not be used in patients with HCM. (Choice D) ICD therapy is indicated for primary prevention of sudden cardiac death in patients with >1 major high-risk features or for secondary prevention of sudden cardiac death in patients with a history of cardiac arrest or sustained spontaneous ventricular tachycardia. There is no such indication in this patient. high-risk features Educational objective: Negative inotropic agents (beta-blockers, verapamil or disopyramide) are recommended for the medical management of symptomatic patients with HCM and elevated left ventricular outflow tract gradient. Beta-blockers are preferred as initial therapy, and verapamil or disopyramide can be used as additional therapy in patients with persistent symptoms. References: Hypertrophic cardiomyopathy. (http://www.ncbi.nlm.nih.gov/pubmed/22874472) ß Blockers for prevention of exercise-induced left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy. (http://www.ncbi.nlm.nih.gov/pubmed/22633205)

Question 13

A 12-year-old boy is brought to the clinic by his mother for a preparticipation sports physical.  The patient will be starting 6th grade in a few weeks and would like to join his school's cross-country team.  He ran several short races last year and had no chest pain, shortness of breath, or dizziness.  Last year, he did well in school and received mostly As and Bs.  The patient has a good relationship with his parents and has many friends.  He wears eyeglasses for myopia.  He has no allergies or other medical conditions.  His grandfather died of a "brain bleed" at age 75.  The patient's height and weight are at the 98th and 50th percentiles, respectively.  Temperature is 37 C (98.6 F), blood pressure is 110/72 mm Hg, pulse is 80/min, and respirations are 20/min.  Cranial nerves II-XII are intact.  Cardiac examination reveals a regular rate and rhythm.  The lungs are clear to auscultation bilaterally.  Achilles and patellar deep tendon reflexes are 2+ bilaterally.  The patient's arm span to height ratio is increased.  Physical examination is otherwise unremarkable.  Which of the following is the best next step in management?

Accepted Answer

Explanation: 11ec2b69_be37_c85a_8f63_598f854be660_MD0005_00 The most crucial component of a preparticipation sports physical is identification of any risk factors for sudden cardiac death during intense exercise. Evaluation should include close attention to any physical stigmata of undiagnosed Marfan syndrome (MFS). MFS is an autosomal dominant disorder caused by mutations in the FBN1 gene encoding the protein fibrillin-1. This patient has characteristic findings, including tall stature, increased arm span to height ratio, and myopia. Diagnosis is based on the presence of multiple clinical features. The main cause of morbidity and mortality in patients with MFS is aortic root disease, manifesting as aneurysmal dilation, aortic regurgitation, and/or dissection. Patients with suspected MFS require an echocardiogram prior to sports participation. If aortic root disease and/or a family history of aortic dissection or sudden death is present, patients are counseled to avoid strenuous physical activity, with intense/contact sports (eg, track, basketball, football) generally restricted. (Choice B) Klinefelter syndrome (47,XXY) can present with tall stature and is diagnosed by karyotype. However, gynecomastia and small or cryptorchid testes, not seen in this patient, are typically present in Klinefelter syndrome. (Choice C) MRI/MRA of the brain can identify berry aneurysms, which occur more commonly in Ehlers-Danlos syndrome, in contrast to aortic aneurysms in MFS. Joint hypermobility and skin hyperextensibility are characteristic of Ehlers-Danlos syndrome. (Choice D) A patient with a Marfanoid habitus should be restricted from sports participation until the aortic root has been evaluated. (Choice E) Serum growth hormone level is elevated in gigantism. Patients are typically tall but also have excessive weight gain and coarse facial features with frontal bossing, which are not seen in this patient. Educational objective: Marfan syndrome should be suspected in patients with tall stature, myopia, and increased arm span to height ratio. Because these patients are at higher risk for sudden cardiac death due to aortic root disease, screening echocardiography is required prior to sports participation. References: Health supervision for children with Marfan syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/24081994) The preparticipation sports evaluation. (http://www.ncbi.nlm.nih.gov/pubmed/26371570)

Question 14

A 70-year-old man comes to the hospital due to fever, lethargy, productive cough, and shortness of breath.  He has type 2 diabetes mellitus, hypertension, paroxysmal atrial fibrillation, and peripheral vascular disease.  His medications include warfarin, sotalol, insulin detemir, and lisinopril.  Chest x-ray shows infiltrates in the left lung base.  He is admitted and treated with azithromycin, ceftriaxone, and oxygen therapy. 
On the second day of hospitalization, he has 2 episodes of loss of consciousness associated with seizure-like activity.  The telemetry strips during one of these episodes is shown in the exhibit.  Which of the following is most likely to provoke a recurrent event in this patient?

Accepted Answer

Explanation: 11ec2b69_be33_8292_8f63_5d64681b7374_MD0005_00 This patient has developed acquired long QT syndrome (LQTS) as a result of interactions between medications (sotalol and azithromycin). The telemetry strips show 3 sinus beats with a prolonged QT interval, followed by a rapid ventricular rhythm consistent with polymorphic ventricular tachycardia (VT). Torsades de pointes (TdP) refers to the form of polymorphic VT that occurs in the setting of acquired or congenital QT prolongation and is characterized by cyclic alteration of QRS axis and/or morphology. TdP in patients with acquired LQTS is most commonly precipitated by premature ventricular beats followed by a compensatory pause (short-long RR intervals) that initiates the cycle of VT. It can also be provoked in patients with bradyarrhythmias (sinus bradycardia or frequent pauses), referred to as "pause-dependent" LQTS. Other causes of acquired LQTS are electrolyte imbalances (eg, hypomagnesemia, hypokalemia), selective serotonin reuptake inhibitors, hypothermia, and HIV infection. (Choice A) TdP can be triggered by an adrenergic surge (exercise or sudden arousal) in some patients with certain congenital forms of LQTS. However, there is no association with fever. (Choice B) Hyperglycemia (or hypoglycemia) is not a risk factor or trigger for drug-induced TdP. (Choice C) Hypokalemia, hypomagnesemia, and hypocalcemia (less common) increase the risk of developing recurrent episodes of TdP. No association is seen with hypernatremia. (Choice D) Structural heart disease, heart failure, and left ventricular hypertrophy are associated with an increased risk of developing drug-induced TdP. Hypertension alone is not associated with an increased risk of provoking TdP. Educational objective: The presence of bradyarrhythmias (sinus bradycardia or pauses) is associated with an increased risk of developing torsades de pointes in patients with drug-induced acquired long QT syndrome (LQTS). Common medications implicated in LQTS include antipsychotics, antidepressants, macrolides, fluoroquinolones, and antifungals. References: Polymorphic ventricular tachycardia, long QT syndrome, and torsades de pointes. (http://www.ncbi.nlm.nih.gov/pubmed/11233951)

Question 15

A 70-year-old woman is brought to the emergency department by her son for evaluation of shortness of breath. She has had a sensation of choking since last night. According to her son, for the past several weeks she has had a dry cough at night and has been taking over-the-counter cough drops. The patient has had no chest pain, palpitations, back pain, abdominal symptoms, or lightheadedness. She has a history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. She has been refusing statin therapy, as she heard statins cause multiple side effects. The patient has also refused flu vaccinations over the last several years. Her only hospital admission occurred 6 years ago when she underwent a spinal fusion for lower back pain. She does not use tobacco, alcohol, or illicit drugs. Family history is not significant. Temperature is 36.1 C (97 F), blood pressure is 171/102 mm Hg, pulse is 92/min, and respirations are 34/min. Pulse oximetry is 85% on room air. BMI is 29 kg/m². Bilateral crackles are heard on lung examination. There are no heart murmurs. ECG shows normal sinus rhythm, increased voltage in the precordial leads, and T-wave inversion in leads V5 and V6. Chest x-ray is shown in the exhibit. Oxygen is administered via 100% nonrebreather facemask. The patient is responding well to treatment. The second troponin I level is negative. Which of these tests is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Transthoracic echocardiogram should be performed in patients with acute decompensated heart failure (ADHF) of uncertain etiology. In this patient it will allow for confirmation of suspected left ventricular dysfunction (ie, hypertensive cardiomyopathy) and provide an assessment for valvular abnormalities (eg, mitral regurgitation) that may contribute to ADHF. (Choice A) There is no biochemical or significant ECG evidence that myocardial ischemia contributed to this patient's presentation of ADHF. However, if echocardiogram demonstrates left ventricular systolic (rather than only diastolic) dysfunction, stress testing or coronary angiography should be performed to rule out ischemic cardiomyopathy. (Choices B, C, and D) Negative D-dimer testing can rule out acute pulmonary embolism in patients with a low pretest probability of disease. Pulmonary function testing and noncontrast CT scan of the chest can allow for evaluation for other causes of respiratory failure (eg, chronic obstructive pulmonary disease, interstitial lung disease). However, these tests are not indicated in this patient with a clear presentation of ADHF that responded to typical therapy. Educational objective: Transthoracic echocardiogram should be performed in patients with acute decompensated heart failure of uncertain etiology to evaluate for left ventricular and valvular dysfunction. If significant left ventricular systolic dysfunction is present, evaluation for ischemic cardiomyopathy with stress testing or coronary angiography is indicated. References: Management of acute heart failure and the effect of systolic blood pressure on the use of intravenous therapies. (http://www.ncbi.nlm.nih.gov/pubmed/24222833)

Question 16

A 43-year-old man comes to the physician for a follow-up visit.  He was diagnosed with coronary artery disease and received a stent to the left circumflex artery a year ago.  At that time, he was started on aspirin, clopidogrel, metoprolol, and atorvastatin.  About a week ago, the patient was seen in the emergency department for pain in both thighs following a 15-mile walk sponsored by a local organization.  His serum creatine kinase level was 500 units/L (normal 25-90 units/L).  Atorvastatin was discontinued, and he was discharged with a prescription for ibuprofen.  The patient also was advised to consult his primary care physician.  His symptoms have improved markedly since discharge from the emergency department.  His physical examination is normal.  The patient's most current lipid profile, performed about 15 days ago while on medication, shows low-density lipoprotein cholesterol of 132 mg/dL, triglycerides of 100 mg/dL, and high-density lipoprotein cholesterol of 40 mg/dL.  He asks about restarting atorvastatin.  Which of the following is the best recommendation for this patient?

Accepted Answer

Explanation: Statin therapy is an effective treatment for hypercholesterolemia and is recommended for secondary prevention of cardiovascular events in all patients with known coronary heart disease. Statin-induced myopathy is the most common complication of statin use and can range from asymptomatic elevation of serum creatine kinase (CK) levels to rhabdomyolysis. Statins can also potentiate muscle injury with elevation of CK levels in patients with an episode of prolonged vigorous exercise. Patients with symptomatic myopathy from statin use should discontinue therapy. In asymptomatic patients, a CK level >10 times the upper limit of normal range is considered an indication for discontinuation of statin therapy. This patient developed clinically significant myopathy. However, it seems to be temporally related to prolonged exercise as he had tolerated atorvastatin previously without any significant side effects. The most appropriate next step is to recheck CK levels and restart atorvastatin if the levels have normalized. (Choices A, B, and C) The elevated CK levels are most likely related to prolonged vigorous exercise, and atorvastatin should not be completely discontinued. Statin therapy is preferred over non-statin drugs (eg, gemfibrozil, nicotinic acid, ezetimibe) for the secondary prevention of cardiovascular events in patients with known coronary heart disease in light of superior evidence showing reduction in cardiac risk. (Choice E) This patient should have serum CK levels rechecked to ensure that they are normalized prior to restarting therapy with atorvastatin. This will confirm resolution of the initial injury and avoid confounding future assessment in case he was to develop recurrent symptoms. Educational objective: Statin therapy can potentiate muscle injury and elevation of creatine kinase (CK) levels following prolonged and vigorous exercise. Most such patients should be restarted on statin therapy after CK levels have normalized. References: Statin-associated myopathy and its exacerbation with exercise. (http://www.ncbi.nlm.nih.gov/pubmed/20878737)

Question 17

A 62-year-old man is brought to the emergency department with pain and numbness in the right leg.  He says "I was watching television 2 hours ago when the pain started, and then my leg became numb."  Past medical history includes coronary artery disease with anterior wall myocardial infarction, ischemic cardiomyopathy, hypertension, and hyperlipidemia.  He does not adhere regularly to prescribed medications.  The patient does not smoke cigarettes but consumes alcohol occasionally.  He appears to be in significant discomfort due to pain.  His temperature is 36.7 C (98 F), blood pressure is 150/90 mm Hg, pulse is 102/min and regular, and respirations are 14/min.  Physical examination shows a cool right lower extremity with delayed capillary refill.  Even with Doppler examination, no pulses are detected at the right popliteal and dorsalis pedis arteries.  Which of the following is the best next step in the management of this patient?

Accepted Answer

Explanation: 11ec2b69_be30_c370_8f63_bb61cde50b9e_MD0005_00 This patient has acute limb ischemia (ALI) with an immediately threatened extremity. ALI is defined as a sudden decrease in limb perfusion and is most often caused by acute arterial occlusion due to systemic embolism from a cardiac source (eg, atrial fibrillation, left ventricular thrombus, or septic emboli from infective endocarditis). Patients typically have the six P's of acute ischemia: pain, pallor, paresthesia, pulselessness, poikilothermia, and paralysis. Patients with ALI with threatened viability of the limb have severe pain (rest pain) with sensory and/or motor loss, delayed capillary refill, and inaudible arterial Doppler signals. All patients with clinical signs and symptoms of ALI should receive anticoagulation (ie, intravenous heparin bolus followed by continuous heparin infusion) immediately while awaiting further interventions. Anticoagulation prevents thrombus propagation and formation of new distal thrombus due to stasis. Patients with an immediately-threatened extremity are at increased risk for irreversible myonecrosis within 4-6 hours and should have emergency surgical revascularization. (Choice A) Noninvasive vascular imaging with duplex ultrasonography, CT angiography, or magnetic resonance angiography is a reasonable option for patients with viable ALI that is not under immediate threat of tissue necrosis. Such patients typically have intact arterial and venous Doppler signals and no sensory or motor deficits. However, patients with immediately-threatened limbs need urgent surgical revascularization to salvage the limb; obtaining further vascular imaging would lead to an unnecessary delay in definitive care. (Choice C) Observation is not recommended as any further delay in immediate revascularization may result in acute limb necrosis. Prophylactic antibiotics are usually given within 1 hour of surgical revascularization procedures involving groin incisions and are not indicated at this time. (Choice D) Patients with an ischemic but viable extremity on examination can be managed with catheter-based thrombolytic therapy or surgical revascularization. Catheter-based intra-arterial administration has better clinical outcomes and fewer bleeding complications than intravenous administration of thrombolytic agents. However, this patient has a threatened lower extremity and should be managed with emergency surgical revascularization. (Choice E) Transthoracic echocardiogram is not indicated at this time but may be obtained later as part of a comprehensive diagnostic evaluation. Educational objective: Patients with an immediately-threatened extremity (severe pain, delayed capillary refill, absent arterial Doppler signals, and sensory or motor deficits) are at risk for irreversible myonecrosis within 4-6 hours and should have anticoagulation and emergency surgical revascularization. References: Antithrombotic therapy in peripheral artery disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/22315275) Analysis of associated diseases in patients with acute critical lower limb ischemia. (http://www.ncbi.nlm.nih.gov/pubmed/23534299)

Question 18

A 70-year-old man comes to the hospital due to fever, lethargy, productive cough, and shortness of breath.  He has type 2 diabetes mellitus, hypertension, paroxysmal atrial fibrillation, and peripheral vascular disease.  His medications include warfarin, sotalol, insulin detemir, and lisinopril.  Chest x-ray shows infiltrates in the left lung base.  He is admitted and treated with azithromycin, ceftriaxone, and oxygen therapy. On examination, the patient is now awake and alert but oriented only to person.  His blood pressure is 120/70 mm Hg, pulse is 65/min, and respirations are 14/min.  Laboratory tests ordered 30 minutes before the first event are shown below.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Torsade de pointes (TdP) is usually a brief arrhythmia that terminates spontaneously. However, patients can have recurrent episodes in rapid succession, with a risk of degenerating into ventricular fibrillation and death. Intravenous magnesium sulfate is considered the first-line therapy in conscious and hemodynamically stable patients with TdP. It is useful for acute treatment and also for the prevention of recurrent TdP episodes in patients with acquired long QT syndrome (LQTS). Treatment with intravenous magnesium sulfate is effective even in patients with normal serum magnesium levels, and it should not be withheld or delayed in patients with normal baseline serum magnesium levels. (Choice A) Amiodarone is a class III antiarrhythmic agent that can markedly prolong the QT interval. It has no role in the acute therapy or prevention of TdP. (Choice B) Class IB antiarrhythmic drugs (eg, lidocaine, phenytoin) shorten the action potential duration and have been effective in the acute management of TdP in some cases. However, these drugs are less effective and predictable and should not be used as initial acute therapy for TdP. (Choice D) Metoprolol has beta-blocking properties that can cause further bradycardia and increase TdP recurrence. It has no role in the acute termination or prevention of TdP. (Choice E) Temporary transvenous pacing is indicated in patients with long QT-related TdP who do not respond to initial intravenous magnesium sulfate. It is especially useful in the management of patients with LQTS associated with bradycardia or sinus pauses (pause-dependent LQTS). Educational objective: Intravenous magnesium sulfate is indicated as first-line therapy for the treatment and prevention of recurrent episodes of torsade de pointes, regardless of the patient's baseline serum magnesium levels. Temporary transvenous pacing should be used in patients who do not respond to intravenous magnesium sulfate. References: Preventing torsades de pointes by careful cardiac monitoring in hospital settings. (http://www.ncbi.nlm.nih.gov/pubmed/18019519) Drug-induced torsade de pointes. Incidence, management and prevention. (http://www.ncbi.nlm.nih.gov/pubmed/7727055)

Question 19

A 56-year-old man is brought to the emergency department with a 4-hour history of crushing, substernal chest pain.  His ECG shows a 3-mm ST-segment elevation in leads V2-V4.  He is taken for cardiac catheterization and undergoes primary angioplasty and stenting of the occluded mid-left anterior descending artery.  There is 30%-40% stenosis of the right coronary artery that does not require intervention.  After the procedure, the patient is admitted to the coronary care unit.  Echocardiogram shows mild anterior wall hypokinesis and a normal left ventricular ejection fraction.  He remains chest pain free throughout his 3-day hospital stay.  The patient is started on dual antiplatelet therapy.  He begins a progressive supervised activity program, which is uneventful, and he is subsequently discharged home.  At a follow-up appointment 3 weeks later, he reports that he has been walking for 20 minutes each day without any problems.  The patient occasionally has some bleeding when brushing his teeth, but is otherwise asymptomatic.  He asks whether it would be safe for him to resume sexual activity.  Which of the following is the most appropriate recommendation?

Accepted Answer

Explanation: Patients with cardiac disease are often anxious about their ability to engage in sexual activity, especially after a myocardial infarction (MI). Sexual activity is associated with an increase in heart rate and blood pressure, and a small but measurable absolute increase in the risk of MI. Studies have estimated the cardiovascular exertion of sexual activity to be relatively modest, in the range of 3-4 metabolic equivalents. metabolic equivalents In general, based on cardiovascular disease (CVD) status, patients can be classified into 3 categories with regard to sexual activity: Low-risk patients can perform light-intensity exercise without symptoms and should be able to initiate or resume sexual activity. Examples include those with few CVD risk factors, controlled hypertension, asymptomatic left ventricular dysfunction, or successful revascularization of clinically significant lesions (>50%-60%). High-risk patients should be referred for a detailed assessment prior to advising on activity. Examples include those with refractory angina, New York Heart Association class IV heart failure, significant arrhythmias, or severe valvular disease. For indeterminate/intermediate-risk patients, stress testing is recommended to reclassify them as low- or high-risk and to help guide decisions. In the period immediately following an acute MI, the myocardium may be vulnerable to increases in demand. Nonetheless, MI patients who have undergone successful revascularization or have no evidence of ischemia on exercise testing can be considered low-risk. They may safely resume sexual intercourse soon after the MI, within 3-4 weeks (Princeton guidelines) and possibly as early as 1 week (American Heart Association guidelines). (Choice B) Dual antiplatelet therapy is not a contraindication to physical activity. It is not unusual for patients on dual antiplatelet therapy to experience a small amount of bleeding when brushing their teeth or shaving; they can be counseled to use a soft toothbrush or an electric razor. (Choices C and D) This patient had successful revascularization, an uncomplicated hospital course, and normal left ventricular function with mild anterior wall hypokinesis (likely myocardial stunning) on echocardiogram. More than 3 weeks after his MI, he is asymptomatic and able to perform moderate walking (corresponding to sexual intercourse in metabolic equivalents). He can be classified as a low-risk patient and should be able to resume sexual activity at this time without further stress testing; he does not need to defer sexual activity to allow for myocardial remodelling. (Choice E) The patient may participate in cardiac rehabilitation, but this should not impact his ability to engage in sexual activity, especially if he remains asymptomatic. Educational objective: Patients who are at low risk of developing cardiovascular complications can initiate or resume sexual activity soon after myocardial infarction. References: Sexual activity and cardiovascular disease: a scientific statement from the American Heart Association. (http://www.ncbi.nlm.nih.gov/pubmed/22267844) The second Princeton consensus on sexual dysfunction and cardiac risk: new guidelines for sexual medicine. (http://www.ncbi.nlm.nih.gov/pubmed/16409215) The Princeton III Consensus recommendations for the management of erectile dysfunction and cardiovascular disease. (http://www.ncbi.nlm.nih.gov/pubmed/22862865)

Question 20

A 57-year-old woman undergoes aortic valve replacement with a bileaflet mechanical valve for bicuspid aortic valve stenosis after an episode of syncope.  Her past medical history is also significant for hypertension.  Preoperative coronary angiogram showed no evidence of coronary artery disease and postoperative course was uncomplicated.  Six months later, she comes to the physician for follow-up.  Her medications include aspirin, warfarin, amlodipine, and candesartan.  Transthoracic echocardiogram shows a mildly enlarged left atrium, left ventricular ejection fraction of 60%, a normally functioning mechanical aortic valve, and normal aortic root size.  Which of the following is the best treatment option for this patient?

Accepted Answer

Explanation: 11ec2b69_be38_649b_8f63_49a1ed0a7355_MD0005_00 The risk of systemic thromboembolism (eg, stroke) is approximately 4% per patient per year in those with mechanical prosthetic valves with no anticoagulation, compared to about 2% in patients treated with aspirin, and <1% in patients treated with warfarin. Patients with mechanical mitral valves have twice the risk compared to those with aortic valve prostheses. Therefore, long-term treatment with aspirin and warfarin is recommended for all patients with mechanical aortic or mitral valve replacement to reduce the rates of systemic thromboembolism. Current guidelines on the target International Normalized Ratio (INR) vary with the valve position (aortic vs mitral), type of mechanical valve, and associated comorbid conditions. In patients with mechanical aortic valve and no other risk factors (eg, atrial fibrillation, severe left ventricular dysfunction [ejection fraction <30%], prior thromboembolism, presence of hypercoagulable state), guidelines recommend long-term treatment with aspirin and warfarin to achieve a goal INR of 2.0-3.0.(Choice A) Patients who cannot take warfarin due to bleeding complications may benefit from aspirin therapy alone. (Choice C) INR goal of 2.5-3.5 is recommended in patients with mechanical mitral valves and those with mechanical aortic valves and associated risk factors. (Choices D and E) Combined antiplatelet (aspirin) and anticoagulant (warfarin) therapy significantly reduces the risk of thromboembolism and mortality compared to anticoagulant therapy alone. Educational objective: Antithrombotic therapy with aspirin and warfarin is recommended for all patients with mechanical aortic or mitral valve replacement to reduce the rates of systemic thromboembolism. Target International Normalized Ratio (INR) for aortic valves without risk factors is 2.0-3.0. Target INR for mechanical aortic valves with high-risk features (eg, atrial fibrillation, left ventricular dysfunction [ejection fraction <30%], prior thromboembolism, presence of hypercoagulable state) and mechanical mitral valves is 2.5-3.5. References: Antithrombotic and thrombolytic therapy for valvular disease: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. (http://www.ncbi.nlm.nih.gov/pubmed/22315272)

Exam 1: Advanced Clinical Medicine