Question 41
A clinical study is performed to document complications following upper respiratory tract infections with group A beta hemolytic streptococci, compared to a control group of patients with Libman-Sacks endocarditis. It is observed that 2 to 5 weeks following initial infection, some persons with the prior streptococcal infection developed fever, with laboratory studies showing an elevated antistreptolysin O and anti-DNAse B titer. Which of the following abnormalities is most likely to appear in the control group?
A Carditis
B Glomerulonephritis
C Erythema marginatum
D Migratory polyarthritis
E Sydenham's chorea
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(B) CORRECT. Strains of streptococci which cause acute rheumatic fever are not the same as the strains which can produce a post-streptococcal glomerulonephritis. Libman-Sacks endocarditis is most often seen in patients with autoimmune diseases such as systemic lupus erythematosus.
(A) Incorrect. This is one of the Jones' criteria for acute rheumatic fever.
(C) Incorrect. This is one of the Jones' criteria for acute rheumatic fever.
(D) Incorrect. This is one of the Jones' criteria for acute rheumatic fever.
(E) Incorrect. This is one of the Jones' criteria for acute rheumatic fever.
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Question 42
A 53-year-old man has had malaise for the past 3 months. On physical examination he is afebrile. On auscultation of the chest, heart sounds are distant and there is a friction rub. An echocardiogram shows a pericardial fluid collection. A pericardiocentesis yields 10 mL of bloody fluid. Which of the following conditions is most likely to give rise to these findings?
A Autoimmune disease
B Chronic renal failure
C Rheumatic fever
D Metastatic carcinoma
E Acute myocardial infarction
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(D) CORRECT. Pericardial tumor and tuberculosis are the typical causes for a hemorrhagic pericarditis.
(A) Incorrect. Serous or fibrinous pericarditis is more common with SLE and other autoimmune diseases.
(B) Incorrect. The pericarditis of uremia is typically fibrinous.
(C) Incorrect. Rheumatic fever is associated with a fibrinous pericarditis.
(E) Incorrect. This may lead to a fibrinous pericarditis.
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Question 43
A 56-year-old man goes to his physician for a routine checkup. He is found to have a blood pressure of 175/110 mm Hg. A month later his blood pressure is 170/105 mm Hg. He elects to do nothing about this, because he feels fine. If he remains untreated, this man is at greatest risk for which of the following conditions?
A Polyarteritis nodosa
B Pulmonary passive congestion
C Hyperplastic arteriolosclerosis
D Tricuspid insufficiency
E Giant cell myocarditis
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(B) CORRECT. The pressure load on the left ventricle leads to left venricular hypertrophy, but eventually the heart can no longer compensate and there is left heart failure, which leads to pulmonary congestion and edema.
(A) Incorrect. Hypertension is not typically related to any of the arteritides.
(C) Incorrect. Hyperplastic arteriolosclerosis can be seen in some cases of malignant hypertension. However, this is an uncommon complication.
(D) Incorrect. Some cardiac dilation may occur along with hypertrophy from hypertension, and this could cause minimal mitral insufficiency, but the tricuspid valve is on the right, and would only be affected after the right heart began to fail.
(E) Incorrect. Hypertension does not lead to myocarditis.
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Question 44
A 48-year-old man has had worsening severe headaches over the past 3 months. There are no abnormal findings on physical examination. Brain MR imaging shows a large 8 cm mass in the right posterior parietal region that extends across the splenium of the corpus callosum. A stereotaxic biopsy reveals an anaplastic astrocytoma. He is treated with radiation and chemotherapy. Several months later he experiences left upper quadrant abdominal pain, accompanied by hematuria. He then has an episode of sudden dyspnea and dies within an hour. At autopsy, large thromboemboli are seen to fill both main pulmonary arterial branches. Which of the following cardiovascular lesions is most likely to be found in this man?
A Tear in the ascending aortic intima
B Occlusive coronary atheromatous plaques
C Hypertrophic cardiomyopathy
D Epicardial metastases
E Small mitral platelet-fibrin thrombi
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(E) CORRECT. A He has both venous and arterial thromboembolic disease that suggests Trousseau syndrome. Non-bacterial thrombotic endocarditis (NBTE) is seen with this paraneoplastic condition. Though the small vegetations are bland, they often embolize, in this case in the systemic circulation to spleen and kidney. The highest rate of Trousseau syndrome occurs with high grade gliomas--about 25% of patients.
(A) Incorrect. Aortic dissection is a medical emergency associated with severe pain. Patients go into shock.
(B) Incorrect. These findings suggest embolic disease, which could come from mural thrombus overlying an area of infarction, but persons with malignant neoplasms tend to have regression of atherosclerosis.
(C) Incorrect. Hypertrophic cardiomyopathy is a process that is not associated with malignancies and is not typically accompanied by embolic events.
(D) Incorrect. Metastases to the heart are most often epicardial and can produce hemorrhagic pericarditis (without tamponade). Embolic events do not occur.
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Question 45
A 50-year-old man has noted increasing swelling of his lower legs along with shortness of breath for 5 months. On physical examination he is afebrile, but diffuse crackles are heard over the lung bases. His heart rate is 80/minute and regular, with no murmurs, rubs, or gallops. A chest radiograph reveals an increased size to the right heart border, along with bilateral pleural effusions. Laboratory studies show a serum troponin I of <0.4>
A Alcoholic cardiomyopathy
B Viral myocarditis
C Bicuspid aortic valve
D Constrictive pericarditis
E Pulmonary interstitial fibrosis
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(E) CORRECT. The findings suggest a predominantly right-sided congestive heart failure, which would be characteristic for cor pulmonale. Pulmonary hypertension most often results from obstructive or restrictive lung diseases.
(A) Incorrect. Alcoholic cardiomyopathy, like dilated cardiomyopathies, involves all four chambers, and he should have signs and symptoms of left as well as right heart failure.
(B) Incorrect. A viral myocarditis tends to affect the whole heart, leading to right and left-sided failure, but the process occurs over days to weeks, not months.
(C) Incorrect. A bicuspid aortic valve tends to calcify in older adults, leading to stenosis and obstruction to left ventricular outflow with signs and symptoms of left heart failure.
(D) Incorrect. Constrictive pericarditis leads to diminished cardiac motion with diminished diastolic filling, and the heart is not increased in size.
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