ABPath Cardiovascular System Pathology 3 — Questions and Answers
Question 1: Concentric left ventricular hypertrophy without dilation is most typical of which cardiomyopathy pattern?
- Dilated cardiomyopathy
- Hypertensive/pressure-overload hypertrophy (Correct answer)
- Restrictive cardiomyopathy
- Arrhythmogenic right ventricular cardiomyopathy
Correct answer: Hypertensive/pressure-overload hypertrophy
Pressure overload (e.g., hypertension, aortic stenosis) causes concentric hypertrophy with parallel sarcomere addition.
Question 2: Myofiber disarray on histology is the hallmark of which condition?
- Dilated cardiomyopathy
- Hypertrophic cardiomyopathy (Correct answer)
- Ischemic cardiomyopathy
- Cardiac sarcoidosis
Correct answer: Hypertrophic cardiomyopathy
Hypertrophic cardiomyopathy shows haphazard myofiber and myofibril disarray, often with sarcomeric gene mutations.
Question 3: Apple-green birefringence under polarized light after Congo red staining indicates deposition of what?
- Hemosiderin
- Amyloid (Correct answer)
- Glycogen
- Calcium
Correct answer: Amyloid
Amyloid shows apple-green birefringence with Congo red and causes restrictive cardiomyopathy.
Question 4: Which infectious agent is classically associated with dilated cardiomyopathy in South America?
- Borrelia burgdorferi
- Trypanosoma cruzi (Correct answer)
- Coxsackievirus A
- Toxoplasma gondii
Correct answer: Trypanosoma cruzi
Chagas disease (Trypanosoma cruzi) is a leading cause of dilated cardiomyopathy in endemic regions.
Question 5: Fibrofatty replacement of the right ventricular myocardium is characteristic of which disorder?
- Restrictive cardiomyopathy
- Arrhythmogenic right ventricular cardiomyopathy (Correct answer)
- Hypertensive heart disease
- Rheumatic heart disease
Correct answer: Arrhythmogenic right ventricular cardiomyopathy
ARVC features fibrofatty replacement of RV myocardium, predisposing to arrhythmias and sudden death.
Question 6: A boggy, dilated heart with a mixed inflammatory infiltrate and myocyte necrosis on biopsy most suggests which diagnosis?
- Lymphocytic myocarditis (Correct answer)
- Amyloidosis
- Hemochromatosis
- Chronic ischemic scarring
Correct answer: Lymphocytic myocarditis
Lymphocytic (often viral) myocarditis shows interstitial lymphocytic infiltrate with adjacent myocyte necrosis.
Question 7: Cardiac hemochromatosis leads to which functional pattern, and iron is best demonstrated by which stain?
- Dilated pattern; PAS stain
- Restrictive/dilated pattern; Prussian blue stain (Correct answer)
- Hypertrophic pattern; Congo red
- Constrictive pattern; trichrome
Correct answer: Restrictive/dilated pattern; Prussian blue stain
Iron overload causes a restrictive-then-dilated cardiomyopathy, and Prussian blue highlights myocyte iron.
ABPath Cardiovascular System Pathology 3
Concentric left ventricular hypertrophy without dilation is most typical of which cardiomyopathy pattern?