Cardiomyopathy Flashcards
(138 cards)
____ mutations with amino acid substitutions and truncating variants are the most common genetic abnormalities in cardiomyopathy.
Missense
The most commonly recognized genetic causes of DCM are truncating mutations of the giant protein ___, encoded by TTN, which maintains sarcomere structure and acts as a key signaling molecule.
titin
Which of the following best defines cardiomyopathy according to the 2013 classification?
A) Cardiac dysfunction caused by structural heart diseases such as coronary artery disease or valve disease.
B) Disorders characterized by morphologically and functionally abnormal myocardium in the absence of any other disease sufficient to cause the observed phenotype.
C) Any diffuse dysfunction attributed to multivessel coronary artery disease.
D) Cardiac abnormalities limited to genetic causes with no acquired component.
B
Which of the following is true about the traditional classification of cardiomyopathies?
A) Hypertrophic cardiomyopathy is characterized by low left ventricular ejection fraction.
B) Restrictive cardiomyopathy is defined primarily by abnormal diastolic function.
C) Dilated cardiomyopathy shows normal left ventricular cavity dimension.
D) The classification triad (dilated, restrictive, hypertrophic) adequately defines all phenotypes and therapies.
B
What is the primary difference between primary and secondary cardiomyopathies in the modern classification system?
A) Primary cardiomyopathies include only acquired causes.
B) Secondary cardiomyopathies are unrelated to systemic diseases.
C) Primary cardiomyopathies affect primarily the heart, while secondary cardiomyopathies result from systemic diseases.
D) Secondary cardiomyopathies are exclusively caused by genetic mutations.
C
What is a key reason that peripheral edema might be absent in young patients with severe fluid retention in cardiomyopathy?
A) Peripheral vasoconstriction prevents visible edema.
B) Fluid retention often manifests as abdominal discomfort due to hepato-splanchnic congestion and ascites.
C) Younger patients compensate by increasing diuresis.
D) Edema only occurs during the late stages of disease.
B
Often considered the hallmark of congestion
peripheral edema
What is the most common inheritance pattern seen in familial cardiomyopathies?
A) Autosomal recessive.
B) X-linked.
C) Autosomal dominant.
D) Matrilineal (mitochondrial).
C
Which of the following mutations is most commonly associated with dilated cardiomyopathy (DCM)?
A) Missense mutations causing dominant negative effects.
B) Truncating mutations of the TTN gene encoding titin.
C) Frameshift mutations in mitochondrial DNA.
D) Deletions of the dystrophin gene.
B
What is a key feature of the clinical expression of genetic cardiomyopathy?
A) It is always present at birth in affected individuals.
B) The phenotype is identical among family members with the same mutation.
C) Penetrance is age-dependent and incomplete.
D) Genetic testing always predicts the clinical course of the disease.
C
Which genetic abnormality is most commonly associated with familial hypertrophic cardiomyopathy?
A) Mutations in sarcomeric genes.
B) Mutations in cytoskeletal proteins.
C) Deletions of dystrophin gene.
D) Mutations in mitochondrial DNA.
A
Which of the following clinical features indicates incomplete penetrance in genetic cardiomyopathy?
A) All individuals with a mutation manifest severe disease.
B) The defining phenotype is present at birth.
C) Some individuals with a pathogenic mutation may never develop the disease.
D) Genetic mutations always lead to arrhythmias in affected individuals.
C
Which of the following statements about sex differences in genetic cardiomyopathy is correct?
A) Women are more likely than men to show severe disease.
B) Penetrance and clinical severity are greater in men for most cardiomyopathies.
C) Men and women are equally affected in terms of disease severity.
D) Cardiomyopathy severity depends only on genetic factors, not sex.
B
Mutations in dystrophin, encoded by the DMD gene, primarily result in which condition?
A) Hypertrophic cardiomyopathy (HCM).
B) Restrictive cardiomyopathy.
C) Duchenne’s and Becker’s muscular dystrophy with DCM.
D) Arrhythmogenic cardiomyopathy.
C
Which sarcolemmal channel protein mutation is associated with DCM with conduction disease?
A) SCN5A.
B) TTN.
C) DES.
D) Lamin A/C.
A
What is the hallmark structural feature of dilated cardiomyopathy (DCM)?
A) Thickened ventricular walls with normal cavity size.
B) Enlarged left ventricle with reduced systolic function.
C) Normal left ventricular dimensions with abnormal diastolic function.
D) Concentric hypertrophy with preserved ejection fraction.
B
What is the expected cardiac outcome for patients with fulminant myocarditis who receive timely and aggressive circulatory support?
A) Permanent systolic dysfunction with frequent arrhythmias.
B) Recovery of ejection fraction to near-normal levels, with possible residual diastolic dysfunction.
C) Irreversible progression to dilated cardiomyopathy.
D) High mortality despite therapy in most cases.
B
Which of the following is the most commonly implicated type of pathogen in infective myocarditis?
A) Bacteria.
B) Protozoa.
C) Viruses.
D) Fungi.
C
What is the primary role of Toll-like receptors during the nonspecific (innate) immune response in viral myocarditis?
A) To directly lyse infected cardiomyocytes.
B) To recognize common antigenic patterns and initiate cytokine release.
C) To suppress viral replication.
D) To produce antibodies specific to viral proteins.
B
Which phase of viral myocarditis is characterized by viral infection and replication causing myocardial injury?
A) Secondary acquired (adaptive) immune response.
B) Nonspecific (innate) immune response.
C) Direct viral invasion.
D) Chronic inflammatory phase.
C
Which of the following is a known consequence of prolonged cytokine activation during the acquired immune response in myocarditis?
A) Direct neutralization of viral proteins.
B) Myocyte hypertrophy and ventricular wall thickening.
C) Disruption of collagen and elastin scaffolding, leading to ventricular dilation.
D) Inhibition of profibrotic signaling pathways.
C
What is the typical initial symptom in a young adult with presumed viral myocarditis?
A) Progressive dyspnea and weakness within a few days to weeks following a viral syndrome.
B) Sudden onset of palpitations and syncope without prior illness.
C) Peripheral edema and ascites without systemic symptoms.
D) Chronic chest pain and stable exertional fatigue.
A
hich of the following is a feature of fulminant myocarditis?
A) Gradual worsening of dyspnea over months after a respiratory illness.
B) Rapid progression from febrile respiratory syndrome to cardiogenic shock involving multiple organ systems.
C) Stable ECG changes mimicking pericarditis without hemodynamic compromise.
D) Asymptomatic elevation of cardiac biomarkers following a viral infection.
B
Which of the following diagnostic modalities is increasingly used to support the diagnosis of myocarditis by detecting increased tissue edema and gadolinium enhancement?
A) Echocardiogram.
B) Electrocardiogram (ECG).
C) Magnetic Resonance Imaging (MRI).
D) Endomyocardial biopsy.
C
