MCQs on Valvular Heart Diseases

Written by Dr. Daniel Fraser (MBBS, FRACP) – Physician

Question 1

A 38-year-old school teacher presents to the Emergency Department after she collapsed at school during exercise. She was unconscious for a few seconds with full recovery afterwards. She now complains of shortness of breath but denies chest pain. On examination, a systolic murmur is heard over the right second intercostal space radiating to the apex. Which one of the following could be the most likely diagnosis?

A) Patent ductus arteriosus
B) Aortic stenosis
C) Hypertrophic obstructive cardiomyopathy
D) Ventricular septal defect
E) Mitral stenosis

Correct Answer: B) Aortic stenosis

Exercise-induced collapse and a systolic murmur are most likely to result from structural heart disease such as valvular lesions, especially aortic stenosis (AS).

This patient’s murmur is best heard at the right second intercostal space and radiates to the apex, which is typical for aortic stenosis. The systolic ejection murmur of AS is harsh, commonly heard at the right upper sternal border and may radiate to the carotids or apex.

(Option A) Patent ductus arteriosus causes a continuous (systolic and diastolic) murmur known as Gibson’s murmur, heard best in the left infraclavicular region. It is a congenital condition and rarely presents for the first time in adults.

(Option C) Hypertrophic obstructive cardiomyopathy (HOCM) may cause exertional syncope, but the murmur is usually heard best along the left sternal border, not the right, and does not radiate to the neck.

(Option D) Ventricular septal defect (VSD) produces a holosystolic murmur best heard at the left lower sternal border, not the right upper sternal area.

(Option E) Mitral stenosis causes a diastolic murmur with maximum intensity at the apex, typically not systolic, and therefore unlikely given the auscultation findings.

Hence, based on the site, timing, and radiation of the murmur, aortic stenosis is the most likely diagnosis.

Question 2

A 63-year-old man visits you because of progressive shortness of breath brought on by exertion. He does not smoke and denies any chest pain, known cardiac disease, or hypertension. On examination, a systolic murmur over the left sternal border, a diastolic murmur over the left lower sternal border, and a systolic murmur over the apex are heard. Which one of the following is the most likely diagnosis?

A) Mitral valve stenosis
B) Mitral valve regurgitation
C) Aortic valve stenosis
D) Aortic valve regurgitation
E) Tricuspid valve regurgitation

Correct Answer: D) Aortic valve regurgitation

Aortic regurgitation (AR) is unique among valvular lesions in that it may produce three distinct murmurs:

  1. A diastolic decrescendo murmur over the left lower sternal border, caused by blood leaking from the aorta back into the left ventricle during diastole.
  2. A systolic flow murmur over the left sternal border or apex, due to the increased stroke volume from the regurgitated blood.
  3. In severe AR, an Austin-Flint murmur, a mid-diastolic rumble at the apex, may occur when the regurgitant jet strikes the anterior mitral leaflet, functionally mimicking mitral stenosis.

Other options:

  • (A) Mitral stenosis typically presents with an opening snap and a diastolic rumble at the apex, not a combination of murmurs over multiple regions.
  • (B) Mitral regurgitation causes a holosystolic murmur best heard at the apex, radiating to the axilla.
  • (C) Aortic stenosis produces a systolic ejection murmur at the right second intercostal space, often radiating to the neck.
  • (E) Tricuspid regurgitation produces a holosystolic murmur heard best at the lower left sternal border, often increasing with inspiration (Carvallo sign).

Thus, the constellation of multiple murmurs, including both systolic and diastolic, most strongly points to aortic valve regurgitation.

Question 3

A 67-year-old man presents to his general practitioner with complaints of increasing shortness of breath on exertion and occasional palpitations over the past several months. He also reports waking at night feeling breathless and needing to sit upright to relieve it. He has a past history of hypertension. On examination, his blood pressure is 128/76 mmHg and heart rate is 88 bpm. Cardiovascular examination reveals a pansystolic murmur best heard at the apex and radiating to the axilla. Bibasal crackles are heard on lung auscultation.

Which one of the following is the most likely diagnosis?

A) Aortic stenosis
B) Mitral stenosis
C) Aortic regurgitation
D) Mitral regurgitation
E) Tricuspid regurgitation

Correct Answer: D) Mitral regurgitation

Explanation:
Mitral regurgitation (MR) occurs when the mitral valve fails to close completely during systole, causing blood to leak backward from the left ventricle into the left atrium.

History and symptoms:
Patients often present with exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea, fatigue, and palpitations. These symptoms arise from reduced forward cardiac output and increased pulmonary venous pressure due to the volume overload in the left atrium.

Examination features:
The classic finding is a pansystolic (holosystolic) murmur, best heard at the apex, and typically radiates to the axilla. A displaced apex beat may be present due to left ventricular dilatation. Additional findings may include a soft S1, a widely split S2, and bibasal crackles indicating pulmonary congestion in more advanced cases.

Mitral regurgitation differs from:

  • Aortic stenosis: Ejection systolic murmur best heard at the right upper sternal border, radiating to the carotids.
  • Mitral stenosis: Mid-diastolic murmur with an opening snap, best heard at the apex.
  • Aortic regurgitation: Early diastolic decrescendo murmur best heard at the left sternal edge.
  • Tricuspid regurgitation: Pansystolic murmur at the lower left sternal border, which increases with inspiration (Carvallo’s sign).

Diagnosis is confirmed by echocardiography, which evaluates valve structure and function, and quantifies the severity of regurgitation.

2. Cardiology Module