Cardiomegaly Case 2

Cardiomegaly Case 2

A 23-year-old man presents to the urgent care clinic complaining of severe throat pain, fever, chills, and diffuse joint pains. He first developed symptoms two weeks ago and was evaluated by another physician at the same clinic. A throat culture was done, and the patient was given a
prescription for antibiotics that he did not filI. He now returns with a worsening of his symptoms. He has since developed severe joint pain and swelling, which first affected his right wrist, then spread to both knees, and now has also affected his left ankle. He also complains of
moderate to severe chest discomfort and shortness of breath. His temperature is 38.7 C (101.6 F), blood pressure is 118/86 mm Hg, pulse is 104/min, and respirations are 20/min. There is an exudate on his oropharynx and bilateral anterior cervical lymphadenopathy. On lung examination, there are bibasilar crackles, and the cardiac examination reveals tachycardia, but a normal rhythm and no murmurs or rubs. Examination of his joints reveals synovitis in his right wrist, Ieft ankle, and both knees.

Q 1:
Which of the following is the most likely cause of this patient's cardiac findings?
/ A. Acute myocardial infarction
/ B. Aortic dissection
/ C. Mitral regurgitation
/ D. Myocarditis
/ E. Wolff-Parkinson-White (WPW) syndrome

Q 2
What underlying condition can explain the patient's upper respiratory as well as cardiac and joint signs and symptoms?
/ A. Acute rheumatic fever
/ B. Budd-Chiari syndrome
/ C. Ebstein's anomaly
/ D. Sjögren syndrome
/ E. Takayasu arteritis

Q 3
Which of the following test results would help confirm the most likely diagnosis?
/ A. EIevated antinuclear antibody
/ B. Low anti-deoxyribonuclease B titer
/ C. Low anti-hyaluronidase titer
/ D. Low anti-streptolysin O titer
/ E. Throat culture positive for group A streptococci

Q 4
A biopsy of the affected cardiac tissue would most likely show which of the following?
/ A. Angiosarcoma
/ B. Aschoff body
/ C. Atheromas
/ D. Hyperplastic arteriolosclerosis
/ E. Libman-Sacks lesions


Q5
The patient continues to deteriorate, he develops worsening heart failure, and requires transfer to the intensive care unit for use of an
inotropic agent to increase his cardiac output. Which of the following agents would most likely be used?
/ A. Benazepril
/ B. Diltiazem
/ C. Dobutamine
/ D. Metoprolol
/ E. Phenylephrine

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Cardiomegaly Case 2 Answers
A1
The correct answer is D. The patient has myocarditis, which is an inflammation of the cardiac muscle. It is most commonly the result of an infectious process. Signs and symptoms can range from an asymptomatic state to arrhythmias, heart failure, and death. The patient often has an antecedent infection, and in this case, he had an exudative pharyngitis.
Acute myocardial infarction (choice A) usually presents with severe squeezing left-sided chest pain that can radiate down the left arm. Patients are generally middle-aged, and can have risk factors for cardiac disease such as hypertension, diabetes, hypercholesterolemia, or a history of tobacco use. The electrocardiogram can vary from nonspecific T wave changes to ST segment elevation.
Aortic dissection (choice B) would present as sudden onset of severe chest pain, which often radiates to the back. Patients can have hypotension, depending on the severity of the dissection, or hypertension, which is often a predisposing factor. Patients can also have unequal pulses in their extremities, if the dissection affects one of the major arteries branching off the aortic arch.
Mitral regurgitation (choice C) is a result of mitral valve insufficiency, in which there is a regurgitant flow of blood across the mitral valve, from the left ventricle, into the left atrium, during systole. It is often due to rheumatic heart disease, but can also result from mitral valve prolapse, or papillary muscle rupture. Physical examination should reveal a holosystolic murmur, heard best at the apex.
Wolff-Parkinson-White (WPW) syndrome (choice E) is a ventricular preexcitation syndrome associated with an atrioventricular bypass track. Patients often have paroxysmal tachycardias, and an electrocardiogram will often reveal a shortened PR interval, a delta wave, and a wide QRS complex.

A2
The correct answer is A. Acute rheumatic fever is an inflammatory disorder that affects multiple systems. There are five major criteria for rheumatic fever: carditis, migratory polyarthritis, subcutaneous nodules, Sydenham chorea, and erythema marginatum. There are also minor criteria: fever, arthralgia, elevated acute phase reactants, and a prolonged PR interval.
Budd-Chiari syndrome (choice B) is an occlusion of the major hepatic veins, which leads to congestive liver disease. Patients often have abdominal pain, jaundice, and hepatomegaly.
Ebstein's anomaly (choice C) is due to an anomalous attachment of the tricuspid leaflets, and results in downward displacement of the tricuspid valve into the right ventricle. This results in tricuspid regurgitation. Symptoms can vary from cyanosis to arrhythmias.
Sjögren syndrome (choice D) is an autoimmune disorder characterized by inflammatory changes in glands, producing dry eyes and dry mouth.
Takayasu arteritis (choice E) is a vasculitis syndrome that affects medium to large arteries, in particular, the aortic arch and its branches. It is also known as "pulseless disease" because patients have weak or absent pulses in their upper extremities. It primarily affects young Asian females.

A3
The correct answer is E. To meet criteria for the diagnosis of rheumatic fever, patients must have either two major, or 1 major and 2 minor criteria, plus evidence of an antecedent streptococcal infection. A throat culture positive for group A streptococci would fulfill the criteria in the presence of myocarditis and migratory polyarthritis.
Elevated antinuclear antibody (choice A) is not associated with rheumatic fever. In the appropriate clinical setting, it is helpful in the diagnosis of rheumatologic disorders such as systemic lupus erythematous.
Anti-streptolysin O (choice D), anti-deoxyribonuclease B (choice B), and anti-hyaluronidase (choice C) are all streptococcal antibody tests. In the setting of rheumatic fever associated with a recent group A streptococcal infection, the titers for these antibody tests would be elevated (in the absence of infection, they may actually be undetectable). A significant titer of any of these antibody tests would meet criteria for the documentation of an antecedent streptococcal infection.

A4
The correct answer is B. The Aschoff body is the classic lesion of rheumatic fever. It is an area of focal interstitial myocardial inflammation. It is characterized by large cells, known as Anitschkow myocytes, and Aschoff cells, which are multinucleated giant cells.
Angiosarcoma (choice A), a rare malignant tumor affecting the vascular tissue, can occur in the skin, breast, liver, or musculoskeletal system.
Atheromas (choice C) are fibrous plaques within the intima of arteries. They are a finding of atherosclerosis.
Hyperplastic arteriolosclerosis (choice D) is characterized by concentric, laminated thickening of arteriolar walls. It often occurs in the kidneys, and may lead to malignant nephrosclerosis.
Libman-Sacks lesions (choice E) are small vegetations that occur on valvular heart tissue. They can occur on either side of the valve, and are associated with endocarditis in systemic lupus erythematous

A5
The correct answer is C. Dobutamine is a positive inotropic agent used in severe cases of heart failure that require inotropic support.
Benazepril (choice A) is an angiotensin converting enzyme inhibitor. Medications in this class can be used in heart failure to decrease afterload, but they do not have any direct affect on cardiac tissue.
Diltiazem (choice B) and metoprolol (choice D) are both negative inotropic agents. When used in the setting of acute heart failure, the patient's course can worsen, although beta blockers such as metoprolol and carvedilol (mixed alpha and beta blocker) are sometimes cautiously used in some patients with CHF.
Phenylephrine (choice E) is an alpha-receptor agonist. It causes vasoconstriction, and is used in severe cases of hypotension