Cardiomyopathy Flashcards
____ 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
What is a primary indication for performing an endomyocardial biopsy in a patient with suspected myocarditis?
A) Elevated cardiac biomarkers without symptoms.
B) Evidence of conduction blocks or ventricular tachyarrhythmias with new-onset heart failure.
C) Mild left ventricular dysfunction on echocardiogram.
D) Chronic dyspnea without a clear diagnosis.
B
What laboratory finding supports a diagnosis of acute viral myocarditis when comparing acute and convalescent blood samples?
A) Elevated anti-heart antibodies.
B) Increasing circulating viral titers.
C) Persistent elevation of CK-MB.
D) Normal troponin levels with ECG abnormalities.
B
The most common cause of death in patients with this infection (Diphtheria)
Cardiac
The most commonly diagnosed noninfective inflammatory process affecting the myocardium is _____, including both _____ and ____
granulomatous myocarditis
sarcoidosis
giant cell myocarditis.
___ is the most common toxin implicated in chronic DCM.
Alcohol
_____ are the most common drugs implicated in toxic cardiomyopathy.
Chemotherapy agents
The most common restrictive cardiomyopathy is ____, in which a common protein assembles into β-pleated sheets of amyloid fibrils that infiltrate between cells of target organs
amyloidosis
There are multiple mutations in the transthyretin molecule, of which the most common is ____, which confers a 50% increased risk of heart failure in the 3-4% of African Americans who are heterozygous, but it is often clinically silent.
V1221
Endomyocardial biopsy is virtually 100% reliable for the diagnosis of all amyloid due to the characteristic ____ pattern of ___ of the amyloid fibrils under polarized light
birefringence
Congo red staining
____frequently accompany e omyocardial fibrosis but are not common in Löffler’s endocarditis.
Pericardial effusions
Which of the following is characteristic of hypertrophic cardiomyopathy (HCM)?
A. Left ventricular hypertrophy caused by hypertension
B. Left ventricular hypertrophy without a hemodynamic cause
C. Concentric left ventricular hypertrophy caused by infiltrative disease
D. Right ventricular hypertrophy due to pulmonary hypertension
B
Which term is now the preferred nomenclature for hypertrophic cardiomyopathy?
A. Idiopathic hypertrophic subaortic stenosis (IHSS)
B. Hypertrophic obstructive cardiomyopathy (HOCM)
C. Asymmetric septal hypertrophy (ASH)
D. Hypertrophic cardiomyopathy with or without obstruction
D
What percentage of hypertrophic cardiomyopathy cases are associated with sarcomere mutations?
A. 10%
B. 25%
C. 50%
D. 80%
C
Which two genes are most commonly mutated in hypertrophic cardiomyopathy?
A. MYBPC3 and MYH7
B. TNNI3 and TNNT2
C. LAMP2 and PRKAG2
D. GLA and TTN
A
Which maneuver increases the systolic ejection murmur in hypertrophic cardiomyopathy?
A. Squatting
B. Valsalva maneuver
C. Handgrip
D. Passive leg raise
B
The primary imaging modality for diagnosing hypertrophic cardiomyopathy is:
A. Chest X-ray
B. Echocardiography
C. Cardiac catheterization
D. Nuclear perfusion imaging
B
Which feature distinguishes athlete’s heart from hypertrophic cardiomyopathy?
A. Increased wall thickness
B. Diastolic dysfunction
C. Regression of hypertrophy after cessation of training
D. Left ventricular outflow tract obstruction
C
Which feature distinguishes athlete’s heart from hypertrophic cardiomyopathy?
A. Increased wall thickness
B. Diastolic dysfunction
C. Regression of hypertrophy after cessation of training
D. Left ventricular outflow tract obstruction
B
The first-line medication for symptomatic hypertrophic cardiomyopathy is:
A. ACE inhibitors
B. β-blockers
C. Digoxin
D. Nitrates
B
Which of the following is true regarding surgical myectomy?
A. It is associated with high perioperative mortality.
B. It is ineffective for relieving LVOT obstruction.
C. It is the treatment of choice for severe refractory symptoms.
D. It does not improve long-term survival.
C
Alcohol septal ablation achieves symptomatic relief in hypertrophic cardiomyopathy by:
A. Excising the septum
B. Inducing controlled infarction of the proximal septum
C. Replacing the mitral valve
D. Reducing myocardial fibrosis
B
What is the most common complication of surgical myectomy and alcohol septal ablation?
A. Stroke
B. Atrial fibrillation
C. Complete heart block
D. Pulmonary edema
C
A 42-year-old male with known hypertrophic cardiomyopathy presents for routine evaluation. He denies chest pain, dyspnea, or syncope. His echocardiogram shows preserved ejection fraction and no evidence of left ventricular outflow tract (LVOT) obstruction at rest. Risk stratification reveals a family history of sudden cardiac death in a sibling. What is the next best step in management?
A. Prescribe disopyramide to prevent obstruction
B. Implant an implantable cardioverter-defibrillator (ICD)
C. Begin beta-blocker therapy
D. Follow with serial evaluations
B
A 55-year-old woman with hypertrophic cardiomyopathy presents with worsening exertional dyspnea and angina. Physical exam reveals a late-peaking systolic murmur at the left sternal border that increases with the Valsalva maneuver. Echocardiography confirms significant LVOT obstruction. She is on maximal doses of beta-blockers and calcium channel blockers with limited improvement. What is the most appropriate next step?
A. Perform cardiac transplantation
B. Prescribe disopyramide
C. Consider septal ablation
D. Initiate diuretics
B
A 68-year-old man with hypertrophic cardiomyopathy and NYHA class III heart failure presents with severe symptoms despite beta-blockers and disopyramide. Echocardiography shows significant LVOT obstruction with a gradient of 70 mmHg. What is the next step in management?
A. Mitral valve replacement
B. Refer for septal ablation
C. Prescribe high-dose diuretics
D. Reevaluate for underlying causes of symptoms
B
______ is common in patients with hypertrophic cardiomyopathy and may lead to hemodynamic deterioration and embolic stroke.
Atrial fibrillation
A 45-year-old male presents with dyspnea on exertion and significant exertional intolerance. Echocardiography reveals an ejection fraction of 25%, a left ventricular diastolic dimension of 65 mm, and normal left ventricular wall thickness. What is the most likely type of cardiomyopathy?
A. Dilated cardiomyopathy
B. Restrictive cardiomyopathy
C. Hypertrophic cardiomyopathy
D. Constrictive pericarditis
A
Which of the following is a characteristic finding in restrictive cardiomyopathy?
A. Normal atrial size
B. Increased atrial size, often involving both atria
C. Decreased atrial size due to reduced filling pressures
D. Increased left atrial size with normal right atrial size
B
A 52-year-old woman is evaluated for progressive fatigue and shortness of breath. Imaging reveals mild mitral and tricuspid regurgitation associated with endocardial involvement and preserved ejection fraction. Which cardiomyopathy does this most likely represent?
A. Dilated cardiomyopathy
B. Restrictive cardiomyopathy
C. Hypertrophic cardiomyopathy
D. Arrhythmogenic cardiomyopathy
B
Which arrhythmia is most commonly associated with hypertrophic cardiomyopathy?
AF
VTachyarrhythmias
A 60-year-old male presents with abdominal discomfort, ascites, and peripheral edema. He denies pulmonary symptoms such as orthopnea or paroxysmal nocturnal dyspnea. Echocardiography shows normal ejection fraction, mildly reduced LV diastolic dimension, and enlarged atria. Which cardiomyopathy is the most likely diagnosis?
A. Dilated cardiomyopathy
B. Restrictive cardiomyopathy
C. Hypertrophic cardiomyopathy
D. Constrictive pericarditis
B
