Heart Valves Flashcards
What is the primary function of the heart valves?
A) To increase heart rate
B) To regulate the flow of blood between chambers of the heart
C) To generate electrical impulses for heart contraction
D) To supply oxygen to the heart muscle
B) To regulate the flow of blood between chambers of the heart
Rationale: Heart valves ensure that blood flows in one direction, preventing backflow and maintaining efficient circulation between the heart’s chambers and into the body or lungs.
Which valve prevents the backflow of blood from the left ventricle into the left atrium?
A) Aortic valve
B) Mitral valve
C) Pulmonary valve
D) Tricuspid valve
B) Mitral valve
Rationale: The mitral valve is located between the left atrium and left ventricle. It prevents blood from flowing back into the atrium during ventricular contraction.
What is the most common cause of mitral valve stenosis?
A) Hypertension
B) Rheumatic fever
C) Atherosclerosis
D) Congenital heart defect
B) Rheumatic fever
Rationale: Rheumatic fever, often resulting from untreated streptococcal infections, can cause inflammation and scarring of the mitral valve, leading to stenosis.
What is a key risk factor for developing aortic valve stenosis?
A) Diabetes
B) Aging
C) Asthma
D) Hyperthyroidism
B) Aging
Rationale: Aortic valve stenosis commonly occurs due to age-related calcification of the valve, leading to reduced valve opening and impaired blood flow.
Which heart valve condition is characterized by the backflow of blood from the aorta into the left ventricle?
A) Aortic regurgitation
B) Mitral stenosis
C) Tricuspid regurgitation
D) Pulmonary stenosis
A) Aortic regurgitation
Rationale: Aortic regurgitation occurs when the aortic valve fails to close properly, allowing blood to leak back into the left ventricle during diastole.
Which of the following is a common complication of untreated valvular heart disease?
A) Aneurysm
B) Heart failure
C) Myocarditis
D) Bradycardia
B) Heart failure
Rationale: Untreated valvular heart disease can lead to heart failure due to the heart’s inability to pump blood effectively, as valve dysfunction impairs normal circulation.
What is a common symptom of mitral valve prolapse?
A) High fever
B) Sharp chest pain
C) Productive cough
D) Leg swelling
B) Sharp chest pain
Rationale: Patients with mitral valve prolapse may experience sharp, non-exertional chest pain due to abnormal valve movement, but the condition is often asymptomatic.
Which valve is most commonly affected in infective endocarditis?
A) Aortic valve
B) Mitral valve
C) Pulmonary valve
D) Tricuspid valve
B) Mitral valve
Rationale: The mitral valve is the most commonly affected valve in infective endocarditis, particularly in individuals with pre-existing valve damage or prosthetic valves.
What is the preferred diagnostic tool to evaluate heart valve function?
A) Chest X-ray
B) Electrocardiogram (ECG)
C) Echocardiography
D) Cardiac catheterization
C) Echocardiography
Rationale: Echocardiography is the gold standard for evaluating heart valve structure and function, allowing visualization of valve movement and blood flow through the heart.
A 65-year-old patient presents with syncope, exertional dyspnea, and chest pain. Upon auscultation, you hear a harsh systolic ejection murmur at the right upper sternal border that radiates to the carotids. What is the most likely diagnosis?
A) Aortic regurgitation
B) Mitral stenosis
C) Aortic stenosis
D) Tricuspid regurgitation
C) Aortic stenosis
Rationale: The combination of syncope, exertional dyspnea, and chest pain, along with a systolic ejection murmur radiating to the carotids, is characteristic of aortic stenosis, a condition often caused by calcification of the aortic valve in older adults.
A 45-year-old patient with a history of untreated rheumatic fever presents with progressive fatigue and palpitations. Echocardiography reveals left atrial enlargement and restricted movement of the mitral valve leaflets. Which of the following hemodynamic changes is most likely in this patient?
A) Increased left ventricular end-diastolic pressure
B) Increased pulmonary venous pressure
C) Decreased right atrial pressure
D) Decreased pulmonary artery pressure
B) Increased pulmonary venous pressure
Rationale: Mitral stenosis due to rheumatic fever leads to increased pressure in the left atrium, which in turn raises pulmonary venous pressure. This can result in pulmonary congestion and right-sided heart failure if untreated
A 55-year-old patient with known aortic regurgitation presents with worsening dyspnea and fatigue. On physical examination, you note a bounding pulse and a high-pitched, decrescendo diastolic murmur at the left sternal border. Which of the following findings would you expect on echocardiography?
A) Left atrial enlargement
B) Left ventricular hypertrophy
C) Right ventricular hypertrophy
D) Mitral valve prolapse
B) Left ventricular hypertrophy
Rationale: Chronic aortic regurgitation leads to increased volume load on the left ventricle, causing it to dilate and hypertrophy as it tries to compensate for the regurgitated blood. The bounding pulse and decrescendo murmur are classic findings in this condition.
A 38-year-old woman presents with a history of progressive shortness of breath, orthopnea, and palpitations. An echocardiogram shows mitral valve prolapse with significant mitral regurgitation. Which of the following compensatory mechanisms is most likely present in her condition?
A) Increased right atrial pressure
B) Left ventricular dilation
C) Pulmonary artery dilation
D) Increased left atrial contraction force
B) Left ventricular dilation
Rationale: In mitral regurgitation, blood flows back into the left atrium during systole, leading to increased preload in the left ventricle. Over time, this causes dilation of the left ventricle as it attempts to compensate for the increased volume.
A 60-year-old man with a history of bicuspid aortic valve presents with worsening fatigue and exertional dyspnea. His echocardiogram reveals severe aortic stenosis with a valve area of 0.8 cm². What is the most appropriate next step in management?
A) Medical management with beta-blockers
B) Valve replacement surgery
C) Percutaneous coronary intervention
D) Observation with serial echocardiograms
B) Valve replacement surgery
Rationale: Severe aortic stenosis with a valve area of less than 1.0 cm² is considered a critical condition, and symptomatic patients require surgical intervention, typically valve replacement, to prevent progression to heart failure or sudden cardiac death.
A 72-year-old patient presents with complaints of worsening peripheral edema, fatigue, and ascites. He has a history of rheumatic fever. Physical examination reveals a diastolic murmur best heard over the left lower sternal border, and echocardiography shows severe tricuspid regurgitation. Which of the following is the most likely underlying cause?
A) Pulmonary hypertension
B) Left ventricular hypertrophy
C) Chronic obstructive pulmonary disease (COPD)
D) Aortic stenosis
A) Pulmonary hypertension
Rationale: Severe tricuspid regurgitation is often secondary to right ventricular dilation caused by pulmonary hypertension. This is a common consequence of left-sided heart diseases such as mitral stenosis or left ventricular failure, often stemming from previous rheumatic fever.
A 55-year-old man presents with a sudden onset of chest pain and shortness of breath. Physical examination reveals a new holosystolic murmur at the apex. Echocardiography shows rupture of the chordae tendineae. What is the most likely diagnosis?
A) Aortic stenosis
B) Mitral regurgitation
C) Tricuspid stenosis
D) Pulmonary valve stenosis
B) Mitral regurgitation
Rationale: Rupture of the chordae tendineae causes acute mitral regurgitation, leading to a new holosystolic murmur. The sudden backflow of blood into the left atrium can cause pulmonary congestion and rapid hemodynamic deterioration
A 58-year-old woman presents with complaints of palpitations, chest pain, and shortness of breath. Physical examination reveals a mid-systolic click followed by a late systolic murmur. Echocardiography confirms mitral valve prolapse. Which of the following is a common associated finding in this patient?
A) Left ventricular outflow obstruction
B) Mitral regurgitation
C) Aortic stenosis
D) Pulmonary hypertension
B) Mitral regurgitation
Rationale: Mitral valve prolapse is often associated with mitral regurgitation due to the incomplete closure of the mitral valve during systole. The characteristic mid-systolic click is due to the sudden tensing of the prolapsed valve leaflets.
A patient with a history of intravenous drug use presents with fever, new-onset murmur, and signs of heart failure. Blood cultures are positive for Staphylococcus aureus. Echocardiography shows a vegetation on the tricuspid valve. Which of the following is the most likely diagnosis?
A) Non-bacterial thrombotic endocarditis
B) Rheumatic heart disease
C) Infective endocarditis
D) Libman-Sacks endocarditis
C) Infective endocarditis
Rationale: Intravenous drug users are at increased risk for infective endocarditis, particularly affecting the tricuspid valve. Staphylococcus aureus is a common pathogen, and vegetations on the valve can lead to septic emboli and heart failure.
A patient with chronic aortic regurgitation is undergoing serial echocardiograms for monitoring. At what stage of disease progression is surgical intervention typically indicated?
A) When symptoms of heart failure appear
B) As soon as the diagnosis is made
C) When left ventricular end-diastolic dimension (LVEDD) exceeds 60 mm
D) When the ejection fraction drops below 60%
A) When symptoms of heart failure appear
Rationale: In chronic aortic regurgitation, surgical intervention is typically indicated when the patient becomes symptomatic, or there is evidence of left ventricular dysfunction, such as an LVEDD exceeding 60 mm or an ejection fraction below 50%
Which of the following heart valve disorders causes blood to flow from the left ventricle into the left atrium during ventricular systole?
B: Mitral regurgitation. Mitral regurgitation occurs when insufficiency of the mitral valve causes blood to flow from the left ventricle into the left atrium during ventricular systole.
If a valvular lesion causes no symptoms or cardiac dysfunction, management commonly requires which of the following?
A. Diet modification
B. Drug therapy
C. Exercise regimen
D. Periodic monitoring
D: Periodic monitoring. Management of a valvular lesion commonly requires only periodic observation and monitoring, with no active treatment for many years
A 68-year-old woman who requires valve replacement for treatment of aortic stenosis comes to the office to discuss the types of prosthetic valves available. The physician explains that she can choose a bioprosthetic (porcine or bovine) or a mechanical (manufactured) valve. She is not on anticoagulants. It is most appropriate for the physician to recommend the bioprosthetic valve to this patient because of which of the following reasons?
A. Patient age is > 65 years
B. Rate of valve thrombosis is lower
C. Reintervention is less likely
D. Survival rate is higher
A: Patient age is > 65 years. A bioprosthetic valve is recommended to replace the aortic valve for patients > 65.
