Valvular heart disease US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for Valvular heart disease. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Valvular heart disease US Medical PG Question 1: A 62-year-old man comes to the physician for decreased exercise tolerance. Over the past four months, he has noticed progressively worsening shortness of breath while walking his dog. He also becomes short of breath when lying in bed at night. His temperature is 36.4°C (97.5°F), pulse is 82/min, respirations are 19/min, and blood pressure is 155/53 mm Hg. Cardiac examination shows a high-pitch, decrescendo murmur that occurs immediately after S2 and is heard best along the left sternal border. There is an S3 gallop. Carotid pulses are strong. Which of the following is the most likely diagnosis?
- A. Aortic valve regurgitation (Correct Answer)
- B. Tricuspid valve regurgitation
- C. Mitral valve prolapse
- D. Mitral valve regurgitation
- E. Mitral valve stenosis
Valvular heart disease Explanation: ***Aortic valve regurgitation***
- A **high-pitch, decrescendo murmur immediately after S2** and heard best along the **left sternal border** is characteristic of **aortic regurgitation**.
- Symptoms like **dyspnea on exertion** and **orthopnea**, an **S3 gallop**, and a **wide pulse pressure** (155/53 mmHg) further support heart failure due to chronic aortic regurgitation.
*Tricuspid valve regurgitation*
- This typically presents with a **holosystolic murmur** best heard at the **left lower sternal border** that increases with inspiration.
- Clinical signs often include **jugular venous distension** and **peripheral edema**, not primarily a decrescendo diastolic murmur.
*Mitral valve prolapse*
- Characterized by a **mid-systolic click** followed by a **late systolic murmur**, and symptomatically may be asymptomatic or cause palpitations.
- The described diastolic murmur and symptoms of heart failure do not align with mitral valve prolapse.
*Mitral valve regurgitation*
- Typically presents as a **holosystolic murmur** heard best at the **apex** and often radiating to the axilla.
- While it can cause dyspnea and an S3, the character and timing of the murmur reported (decrescendo, immediately after S2) are inconsistent with mitral regurgitation.
*Mitral valve stenosis*
- This condition presents with a **diastolic rumble** heard best at the **apex** with an opening snap.
- The murmur described is a high-pitch decrescendo murmur, which is distinct from the low-pitched rumble of mitral stenosis.
Valvular heart disease US Medical PG Question 2: A 47-year-old man presents for a routine physical examination as part of an insurance medical assessment. He has no complaints and has no family history of cardiac disease or sudden cardiac death. His blood pressure is 120/80 mm Hg, temperature is 36.7°C (98.1°F), and pulse is 75/min and is regular. On physical examination, he appears slim and his cardiac apex beat is of normal character and non-displaced. On auscultation, he has a midsystolic click followed by a late-systolic high-pitched murmur over the cardiac apex. On standing, the click and murmur occur earlier in systole, and the murmur is of increased intensity. While squatting, the click and murmur occur later in systole, and the murmur is softer in intensity. Echocardiography of this patient will most likely show which of the following findings?
- A. Left atrial mass arising from the region of the septal fossa ovalis
- B. Doming of the mitral valve leaflets in diastole
- C. Prolapse of a mitral valve leaflet of ≥2 mm above the level of the annulus in systole (Correct Answer)
- D. Retrograde blood flow into the right atrium
- E. High pressure gradient across the aortic valve
Valvular heart disease Explanation: ***Prolapse of a mitral valve leaflet of ≥2 mm above the level of the annulus in systole***
- The clinical presentation with a **midsystolic click** followed by a **late-systolic high-pitched murmur over the cardiac apex** is characteristic of **mitral valve prolapse (MVP)**.
- The changes in the click and murmur timing and intensity with **standing (earlier, louder)** and **squatting (later, softer)** are classic findings, reflecting changes in left ventricular volume that affect the onset of valve prolapse.
*Left atrial mass arising from the region of the septal fossa ovalis*
- This description is highly suggestive of a **myxoma**, typically found in the left atrium, which can cause symptoms of **obstructive heart failure** or **embolism**.
- A myxoma would not typically present with the characteristic **midsystolic click** and **late-systolic murmur** that changes with position.
*Doming of the mitral valve leaflets in diastole*
- **Doming of the mitral valve leaflets in diastole** is characteristic of **mitral stenosis**, where the valve fails to open properly.
- Mitral stenosis would present with a **diastolic murmur**, not a midsystolic click and late-systolic murmur.
*Retrograde blood flow into the right atrium*
- **Retrograde blood flow into the right atrium** indicates **tricuspid regurgitation**, which would typically manifest as a **holosystolic murmur** best heard at the lower left sternal border, often with prominent jugular venous pulsations.
- This finding is inconsistent with the patient's auscultatory findings at the cardiac apex.
*High pressure gradient across the aortic valve*
- A **high pressure gradient across the aortic valve** signifies **aortic stenosis**, which is characterized by a **systolic ejection murmur** best heard at the right upper sternal border with radiation to the carotids.
- This condition would not produce a midsystolic click or a late-systolic murmur at the apex.
Valvular heart disease US Medical PG Question 3: A 32-year-old male presents for a new patient visit. He states that he is in good health but has had decreasing exercise tolerance and increased levels of shortness of breath over the past 5 years. He believed that it was due to aging; he has not seen a doctor in 10 years. On auscultation, you note an early diastolic decrescendo blowing murmur that radiates along the left sternal border. In the United States, what is the most likely cause of this patient's condition?
- A. Connective tissue disease
- B. Congenital bicuspid aortic valve (Correct Answer)
- C. Syphilis
- D. Rheumatic heart disease
- E. Myxomatous degeneration
Valvular heart disease Explanation: ***Congenital bicuspid aortic valve***
- The patient's age (32 years old), progressive symptoms of **aortic regurgitation** (decreasing exercise tolerance, shortness of breath, early diastolic decrescendo murmur), and location of the murmur are highly suggestive of a **bicuspid aortic valve**.
- This is the **most common congenital heart defect**, affecting 1-2% of the population, and is the leading cause of **aortic stenosis** and **aortic insufficiency** in younger adults in developed countries.
*Connective tissue disease*
- While connective tissue diseases such as **Marfan syndrome** or **Ehlers-Danlos syndrome** can cause aortic root dilation and regurgitation, they are less common than a bicuspid aortic valve as a primary cause of isolated aortic regurgitation in this age group.
- These conditions typically present with other systemic features (e.g., arachnodactyly, skin hyperextensibility) that are not mentioned in the patient's history.
*Syphilis*
- **Syphilitic aortitis** can cause aortic root dilation and aortic regurgitation, typically as a late-stage manifestation of **tertiary syphilis**.
- While possible, it is less common in developed countries today due to effective antibiotic treatment, and the patient's asymptomatic progression over 5 years might suggest a congenital rather than an infectious cause in this context.
*Rheumatic heart disease*
- **Rheumatic fever** is a common cause of valvular heart disease globally, but its incidence has significantly declined in developed countries due to improved hygiene and antibiotic use for **streptococcal infections**.
- While it can affect the aortic valve, it more commonly affects the **mitral valve** and usually presents with symptoms earlier in life or with a history of recurrent fevers.
*Myxomatous degeneration*
- **Myxomatous degeneration** primarily affects the **mitral valve**, leading to **mitral valve prolapse** and regurgitation.
- While it can sometimes affect the aortic valve, it is a less common cause of isolated aortic regurgitation and often presents with different clinical features or imaging findings.
Valvular heart disease US Medical PG Question 4: A 43-year-old man presents to his primary care physician for his yearly check-up exam. He has no new concerns but wants to make sure that his hypertension and diabetes are properly controlled. His past medical history is otherwise unremarkable and his only medications are metformin and lisinopril. He has smoked a pack of cigarettes per day since he was 16 years of age and drinks 3 beers per night. Physical exam is remarkable for a murmur best heard in the 5th intercostal space at the left mid-clavicular line. The murmur is high-pitched and blowing in character and can be heard throughout systole. Which of the following properties is characteristic of this patient's most likely disorder?
- A. Radiation of murmur to the axilla (Correct Answer)
- B. Results in mixing of blood between left and right ventricles
- C. Radiation of murmur to the right sternal border
- D. Presents with an opening snap
- E. Radiation of murmur to the neck
Valvular heart disease Explanation: ***Radiation of murmur to the axilla***
- The patient's presentation of a **systolic murmur** best heard at the **5th intercostal space at the left mid-clavicular line** (the apex) strongly suggests **mitral regurgitation**.
- A characteristic feature of **mitral regurgitation** is the **radiation of the murmur to the axilla**.
*Results in mixing of blood between left and right ventricles*
- This describes a **ventricular septal defect (VSD)**, which presents with a holosystolic murmur typically loudest at the **left sternal border** and not the apex.
- While VSD is a systolic murmur, its location and consequence of intracardiac shunting differ from the described clinical picture.
*Radiation of murmur to the right sternal border*
- This type of radiation is commonly associated with benign flow murmurs or sometimes **tricuspid regurgitation**, though tricuspid regurgitation is typically heard loudest at the **lower left sternal border** and increases with inspiration.
- It is not characteristic of a murmur heard best at the apex with the described qualities.
*Presents with an opening snap*
- An **opening snap** is a characteristic finding of **mitral stenosis**, which is a **diastolic murmur**, not a systolic murmur as described in the patient.
- The murmur in this patient is heard throughout systole, ruling out mitral stenosis.
*Radiation of murmur to the neck*
- Radiation to the neck is a classic feature of **aortic stenosis**, which is typically a **systolic ejection murmur** heard best at the **right upper sternal border**, radiating to the carotid arteries.
- This differs significantly from a murmur heard maximally at the apex.
Valvular heart disease US Medical PG Question 5: A 7-year-old boy is brought to the pediatrician by his parents for a routine checkup. The parents note that the patient recently joined a baseball team and has had trouble keeping up with his teammates and gets short of breath with exertion. The patient has otherwise been healthy and has no known history of asthma or allergic reaction. Today, the patient’s temperature is 98.2°F (36.8°C), blood pressure is 112/72 mmHg, pulse is 70/min, and respirations are 12/min. The physical exam is notable for a heart murmur that decreases when the patient bears down. Additionally, the hand grip and rapid squatting maneuvers increase the severity of the murmur. Which of the following is likely heard on auscultation?
- A. Continuous murmur inferior to the left clavicle
- B. Holosystolic murmur at the apex radiating to the axilla
- C. Crescendo-decrescendo systolic murmur radiating to carotids
- D. Late systolic murmur with a midsystolic click
- E. Holosystolic murmur at the lower left sternal border (Correct Answer)
Valvular heart disease Explanation: ***Holosystolic murmur at the lower left sternal border***
- This presentation is classic for a **ventricular septal defect (VSD)**, which is the most common congenital heart defect. The murmur is **holosystolic** and best heard at the **lower left sternal border**.
- The key physiological findings support VSD: the murmur **decreases with Valsalva** (decreased venous return → decreased left-to-right shunt) and **increases with handgrip and squatting** (increased systemic vascular resistance → increased left-to-right shunt across the defect).
- **Exertional dyspnea** in a previously healthy child can occur with moderate-sized VSDs due to increased pulmonary blood flow. Small VSDs may be asymptomatic until increased activity demands reveal the limitation.
*Continuous murmur inferior to the left clavicle*
- This describes a **patent ductus arteriosus (PDA)**, which produces a continuous **"machinery-like" murmur** heard best in the infraclavicular area and under the left clavicle.
- While PDA can cause exertional symptoms, the murmur characteristics don't match the holosystolic pattern described, and the dynamic maneuver responses differ from this case.
*Holosystolic murmur at the apex radiating to the axilla*
- This is the classic presentation of **mitral regurgitation**. The murmur would **increase with squatting** (increased preload), but the location (apex radiating to axilla) doesn't match the lower left sternal border location described.
- Mitral regurgitation is uncommon in otherwise healthy children without rheumatic disease or structural abnormalities.
*Crescendo-decrescendo systolic murmur radiating to carotids*
- This describes **aortic stenosis**, which produces an **ejection systolic murmur** that radiates to the carotids.
- Aortic stenosis has a crescendo-decrescendo (ejection) pattern, not holosystolic, and the location and radiation pattern don't match this patient's findings.
*Late systolic murmur with a midsystolic click*
- This is pathognomonic for **mitral valve prolapse (MVP)**. In MVP, the click and murmur **move earlier and become louder with Valsalva** (decreased ventricular volume allows earlier prolapse), which is opposite to this patient's findings.
- MVP is the opposite response: louder with Valsalva, softer with squatting.
Valvular heart disease US Medical PG Question 6: A 55-year-old woman presents with fatigue, shortness of breath during ordinary activities, and occasional fluttering in her chest. She denies chest pain or lower extremity edema. She has no prior medical history. She does not smoke but drinks alcohol socially. Her blood pressure is 110/70 mm Hg, her temperature is 36.9°C (98.4°F), and her radial pulse is 95/min and regular. On physical examination, lungs are clear to auscultation, the apical impulse is slightly displaced, and a III/VI holosystolic murmur is audible at the apex and radiates to the axilla. Transthoracic echocardiography shows the presence of mitral regurgitation and an ejection fraction of 60 %. Which of the following is the optimal therapy for this patient?
- A. ACE inhibitors, beta-blockers, diuretics, and surgery (Correct Answer)
- B. Intra-aortic balloon counterpulsation
- C. Observation and echocardiographic followup
- D. Emergency surgery
- E. Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers
Valvular heart disease Explanation: ***ACE inhibitors, beta-blockers, diuretics, and surgery***
- This patient has **symptomatic chronic primary mitral regurgitation (MR)** with preserved ejection fraction, presenting with fatigue, dyspnea, and palpitations.
- According to **current ACC/AHA guidelines**, the definitive treatment for **symptomatic severe chronic primary MR** is **surgical intervention** (mitral valve repair or replacement).
- **Mitral valve repair** is preferred over replacement when feasible, with excellent outcomes in experienced centers.
- Medical management with **diuretics** may provide symptomatic relief for volume overload, while surgery addresses the underlying valvular pathology.
- **Note:** ACE inhibitors and vasodilators are **not recommended** for chronic primary MR with preserved LV function per current guidelines, but may be initiated if there is concurrent hypertension or as bridge therapy before surgery.
*Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers*
- **ACE inhibitors and vasodilators have no proven benefit** in chronic primary mitral regurgitation with preserved left ventricular function.
- These medications are primarily useful for **secondary (functional) MR** due to LV dysfunction or heart failure with reduced ejection fraction.
- Current guidelines **do not recommend** ACE inhibitors as primary therapy for chronic primary MR.
*Intra-aortic balloon counterpulsation*
- This therapy is used for **acute severe mitral regurgitation** or **cardiogenic shock** to improve cardiac output and reduce afterload.
- The patient has **chronic symptoms** and is **hemodynamically stable** with preserved EF, so this aggressive intervention is not indicated.
*Observation and echocardiographic followup*
- This approach is suitable for **asymptomatic patients with mild to moderate chronic primary MR** and preserved left ventricular function.
- However, this patient is experiencing **significant symptoms** (fatigue, dyspnea, palpitations), indicating that observation alone is insufficient.
*Emergency surgery*
- **Emergency surgery** is reserved for **acute, severe MR** with hemodynamic instability or pulmonary edema.
- This patient has **chronic compensated symptoms** with preserved EF, warranting **elective surgical evaluation** rather than emergency intervention.
Valvular heart disease US Medical PG Question 7: A 26-year-old woman comes to the physician for a pre-employment examination. She has no complaints. She has a history of polycystic ovarian syndrome. She exercises daily and plays soccer recreationally on the weekends. Her mother was diagnosed with hypertension at a young age. She does not smoke and drinks 2 glasses of wine on the weekends. Her current medications include an oral contraceptive pill and a daily multivitamin. Her vital signs are within normal limits. Cardiac examination shows a grade 1/6 decrescendo diastolic murmur heard best at the left sternal border. Her lungs are clear to auscultation bilaterally. Peripheral pulses are normal and there is no lower extremity edema. An electrocardiogram shows sinus rhythm with a normal axis. Which of the following is the most appropriate next step in management?
- A. Exercise stress test
- B. No further testing
- C. CT scan of the chest with contrast
- D. Transthoracic echocardiogram (Correct Answer)
- E. X-ray of the chest
Valvular heart disease Explanation: ***Transthoracic echocardiogram***
- A **grade 1/6 decrescendo diastolic murmur** heard best at the **left sternal border** is consistent with **aortic regurgitation** and warrants further investigation with a **transthoracic echocardiogram** to evaluate for potential cardiac abnormalities, such as **bicuspid aortic valve** or **aortic regurgitation**, which can be congenital and lead to complications.
- Given the patient's young age, active lifestyle, and family history of hypertension, even a subtle cardiac finding should be thoroughly investigated to rule out underlying structural heart disease.
- **All diastolic murmurs are pathological** and require imaging evaluation.
*Exercise stress test*
- An **exercise stress test** is typically used to evaluate **ischemic heart disease** or exercise-induced arrhythmias, neither of which are suggested by the patient's presentation or murmur.
- It would not provide diagnostic information regarding the **etiology of a diastolic murmur**.
*No further testing*
- A **diastolic murmur** is almost always pathological and should be further investigated, even if the patient is asymptomatic.
- Ignoring a diastolic murmur could lead to delayed diagnosis and treatment of a potentially serious underlying cardiac condition.
*CT scan of the chest with contrast*
- A **CT scan of the chest** is not the primary imaging modality for evaluating heart murmurs.
- It is more commonly used for evaluating pulmonary diseases, aortic aneurysms, or aortic dissection, none of which are indicated here.
*X-ray of the chest*
- A **chest X-ray** can show gross cardiac enlargement or pulmonary congestion but will not provide the detailed anatomical and functional information needed to diagnose the cause of a diastolic murmur.
- It has low sensitivity for diagnosing specific valvular abnormalities.
Valvular heart disease US Medical PG Question 8: A 36-year-old healthy man presents to his physician to discuss his concerns about developing heart disease. His father, grandfather, and older brother had heart problems, and he has become increasingly worried he might be at risk. He takes no medications and his past medical history is only significant for an appendectomy at 20 years ago. He is married happily with 2 young children and works as a hotel manager and exercises occasionally in the hotel gym. He drinks 3–5 alcoholic beverages per week but denies smoking and illicit drug use. Today his blood pressure is 146/96 mm Hg, pulse rate is 80/min, and respiratory rate is 16/min. He has a body mass index of 26.8 kg/m2. His physical examination is otherwise unremarkable. Laboratory tests show:
Laboratory test
Serum glucose (fasting) 88 mg/dL
Serum electrolytes
Sodium 142 mEq/L
Potassium 3.9 mEq/L
Chloride 101 mEq/L
Serum creatinine 0.8 mg/dl
Blood urea nitrogen 10 mg/dl
Cholesterol, total 350 mg/dL
HDL-cholesterol 40 mg/dL
LDL-cholesterol 280 mg/dL
Triglycerides 130 mg/dL
Besides appropriate medications for his cholesterol and a follow-up for his hypertension, which of the following supplements is thought to provide a protective cardiovascular effect?
- A. Folic acid (Correct Answer)
- B. Thiamine
- C. Vitamin K
- D. Vitamin B12
- E. Vitamin E
Valvular heart disease Explanation: ***Folic acid***
- Folic acid (Vitamin B9) is involved in the metabolism of **homocysteine**, and elevated homocysteine levels are associated with increased cardiovascular risk.
- **Historically**, it was hypothesized that lowering homocysteine with folic acid would reduce cardiovascular events.
- However, **large randomized controlled trials (HOPE-2, NORVIT, VISP) have failed to demonstrate cardiovascular benefit** from folic acid supplementation despite successfully lowering homocysteine levels.
- Among the options listed, folic acid was the supplement most **historically thought** to provide cardiovascular protection, though current evidence does not support routine supplementation for this purpose.
- **Current guidelines do NOT recommend** folic acid supplementation for cardiovascular disease prevention in the general population.
*Thiamine*
- **Thiamine** (Vitamin B1) is crucial for carbohydrate metabolism and nerve function.
- Thiamine deficiency can lead to **beriberi** (including wet beriberi with cardiac manifestations), but supplementation in individuals without deficiency provides **no cardiovascular protection**.
*Vitamin K*
- **Vitamin K** is essential for blood clotting and bone metabolism, and may play a role in preventing vascular calcification.
- However, there is **insufficient evidence** to recommend vitamin K supplementation for cardiovascular protection in clinical practice.
*Vitamin B12*
- **Vitamin B12** is important for nerve function, red blood cell formation, and homocysteine metabolism.
- Like folic acid, B12 was studied for cardiovascular protection through homocysteine reduction, but **clinical trials failed to show benefit**.
- Routine B12 supplementation for cardiovascular protection in individuals with normal B12 levels is **not recommended**.
*Vitamin E*
- **Vitamin E** is an antioxidant that was extensively studied for cardiovascular protection in the 1990s-2000s.
- **Large clinical trials (HOPE, GISSI) conclusively showed NO cardiovascular benefit** from vitamin E supplementation, and some studies suggested potential harm at high doses.
- Vitamin E supplementation for cardiovascular disease prevention is **not recommended**.
Valvular heart disease US Medical PG Question 9: A 43-year-old woman presents to the emergency department complaining of palpitations, dry cough, and shortness of breath for 1 week. She immigrated to the United States from Korea at the age of 20. She says that her heart is racing and she has never felt these symptoms before. Her cough is dry and is associated with shortness of breath that occurs with minimal exertion. Her past medical history is otherwise unremarkable. She has no allergies and is not currently taking any medications. She is a nonsmoker and an occasional drinker. She denies illicit drug use. Her blood pressure is 100/65 mm Hg, pulse is 76/min, respiratory rate is 23/min, and temperature is 36.8°C (98.2°F). Her physical examination is significant for bibasilar lung crackles and a non-radiating, low-pitched, mid-diastolic rumbling murmur best heard at the apical region. In addition, she has jugular vein distention and bilateral pitting edema in her lower extremities. Which of the following best describes the infectious agent that led to this patient’s condition?
- A. A bacterium that induces partial lysis of red cells with hydrogen peroxide
- B. A bacterium that requires an anaerobic environment to grow properly
- C. A bacterium that does not lyse red cells
- D. A bacterium that induces heme degradation of the red cells of a blood agar plate
- E. A bacterium that induces complete lysis of the red cells of a blood agar plate with an oxygen-sensitive cytotoxin (Correct Answer)
Valvular heart disease Explanation: ***A bacterium that induces complete lysis of the red cells of a blood agar plate with an oxygen-sensitive cytotoxin***
- This describes **Group A Streptococcus (GAS)**, specifically *Streptococcus pyogenes*, which causes **rheumatic fever** leading to **mitral stenosis**. Mitral stenosis is characterized by a **mid-diastolic rumbling murmur** at the apex, left atrial enlargement causing **palpitations**, and **pulmonary congestion** leading to dyspnea, cough, and bibasilar crackles.
- The delayed onset of symptoms (immigrated at 20, symptoms at 43) is typical for **rheumatic heart disease**, where repeated GAS infections in childhood/adolescence lead to valve damage that manifests years later. GAS produces **streptolysin O**, an **oxygen-labile cytotoxin** responsible for **beta-hemolysis** (complete lysis) on blood agar.
*A bacterium that induces partial lysis of red cells with hydrogen peroxide*
- This describes **alpha-hemolytic** bacteria like *Streptococcus pneumoniae* or *Viridans streptococci*, which cause **partial hemolysis** (greenish discoloration) on blood agar due to **hydrogen peroxide** production.
- While *Viridans streptococci* can cause **infective endocarditis**, the clinical picture of **rheumatic mitral stenosis** is more consistent with a history of recurrent streptococcal pharyngitis (GAS).
*A bacterium that requires an anaerobic environment to grow properly*
- This description typically refers to **anaerobic bacteria**, such as *Clostridium* or *Bacteroides* species.
- These bacteria are generally not associated with the primary cause of acute rheumatic fever or the subsequent development of chronic valvular heart disease like mitral stenosis.
*A bacterium that does not lyse red cells*
- This describes **gamma-hemolytic** (non-hemolytic) bacteria, such as *Enterococcus faecalis* or some *Staphylococcus* species.
- These organisms do not cause the characteristic hemolysis seen with the streptococci responsible for rheumatic fever.
*A bacterium that induces heme degradation of the red cells of a blood agar plate*
- This description is **too vague** and does not specifically identify the organism. While heme degradation occurs with various types of hemolysis, the key distinguishing feature of **Group A Streptococcus** is **complete lysis (beta-hemolysis)** combined with production of the **oxygen-sensitive toxin streptolysin O**.
- This option lacks the specificity needed to identify GAS as the causative agent of rheumatic fever. Both alpha- and beta-hemolytic organisms can degrade heme, but only beta-hemolytic GAS causes rheumatic heart disease.
Valvular heart disease US Medical PG Question 10: A patient with a history of Tetralogy of Fallot is being evaluated for long-term complications. This patient is at greatest risk of damage to which of the following cardiovascular structures?
- A. Cardiac septum
- B. Coronary artery
- C. Temporal artery
- D. Pulmonary valve (Correct Answer)
- E. Cardiac conduction system
Valvular heart disease Explanation: ***Pulmonary valve***
- Patients with **Tetralogy of Fallot** often have severe **pulmonary stenosis**, which can lead to significant long-term damage and insufficiency of the pulmonary valve, frequently requiring replacement.
- The elevated right ventricular pressure from **outflow obstruction** and the **ventricular septal defect** alter flow dynamics, putting continuous strain on the pulmonary valve and the right ventricular outflow tract.
*Cardiac septum*
- While a **ventricular septal defect (VSD)** is a key feature of Tetralogy of Fallot, it is a structural anomaly present from birth and usually does not *suffer additional damage* over time in the same way a valve does, although its size can impact shunt dynamics.
- Damage to the septum itself (beyond the initial defect) is not the primary long-term risk for this cardiovascular structure in Tetralogy of Fallot.
*Coronary artery*
- Anomalies of the **coronary arteries** can occur in Tetralogy of Fallot but are not consistently present and are not the primary structure at greatest risk of *damage* as a direct consequence of the typical hemodynamics of the condition.
- Coronary artery disease is generally a later-life atherosclerotic process and not directly linked to the congenital defect itself.
*Temporal artery*
- The **temporal artery** is an extracardiac artery and is not a cardiovascular structure at risk of damage in Tetralogy of Fallot.
- Conditions like giant cell arteritis affect the temporal artery, which is unrelated to this congenital heart defect.
*Cardiac conduction system*
- While there is a risk of **arrhythmias** in patients with Tetralogy of Fallot, particularly with surgical repairs, the direct *damage* to the cardiac conduction system itself from the pathophysiology is not the greatest risk compared to the structural deterioration of the pulmonary valve.
- Scarring from corrective surgery can predispose to conduction abnormalities, but the primary pathology and greatest unaddressed risk is often related to the right ventricular outflow tract and pulmonary valve.
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