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Library102 banksSample
  • UWorld
  • NBME
  • BoardVitals
  • USMLE-Rx
  • Mehlman
  • PassMedicine
  • CanadaQBank
  • eMedici
  • UWorld · USMLE Step 1QBank3,659 questions11% used · 68% correctNew block
  • UWorld · USMLE Step 2 CKQBank4,085 questionsUnusedNew block
  • NBME · Step 1 ComprehensiveForm 21199 questions100% used · 74% correctNew block
  • BoardVitals · USMLE Step 1QBank3,545 questions2% used · 61% correctNew block
  • USMLE-Rx · USMLE-RxStep 12,150 questions11% used · 71% correctNew block
  • Mehlman · USMLE QbanksStep 1 QBank2,855 questions4% used · 79% correctNew block

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UWorld · USMLE Step 1QBank3,659 questions11% used · 68% correctSelected
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Item: 12 of 40
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A 74-year-old man comes to the physician because of a 4-month history of progressive dyspnea on exertion and two episodes of chest pressure while climbing stairs. His temperature is 36.9°C (98.4°F), pulse is 72/min, respirations are 16/min, and blood pressure is 118/84 mm Hg. The lungs are clear to auscultation. The carotid upstroke is delayed and diminished. Cardiac examination shows a harsh, grade 3/6, late-peaking crescendo-decrescendo systolic murmur at the right upper sternal border that radiates to both carotid arteries. A phonocardiogram and a carotid pulse tracing are shown.

Laboratory studies show:

Hemoglobin14.1 g/dL13.5–17.5 g/dL
Serum
Na⁺139 mEq/L136–146 mEq/L
K⁺4.3 mEq/L3.5–5.0 mEq/L
Urea nitrogen17 mg/dL7–18 mg/dL
Creatinine1.1 mg/dL0.6–1.2 mg/dL
Troponin I0.02 ng/mL≤0.04 ng/mL

Which of the following is the most likely diagnosis?

  • A. Hypertrophic cardiomyopathy
  • B. Aortic stenosis
  • C. Mitral regurgitation
  • D. Pulmonic stenosis
  • E. Aortic regurgitation

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Fig. 1. Phonocardiogram at the right upper sternal border, with lead II and the carotid pulse.Fig. 2. The aortic valve in short axis: three calcified cusps around a narrow orifice.
Q 12 of 40 · TutorBlock time 14:32Sample

A 74-year-old man comes to the physician because of a 4-month history of progressive dyspnea on exertion and two episodes of chest pressure while climbing stairs. His temperature is 36.9°C (98.4°F), pulse is 72/min, respirations are 16/min, and blood pressure is 118/84 mm Hg. The lungs are clear to auscultation. The carotid upstroke is delayed and diminished. Cardiac examination shows a harsh, grade 3/6, late-peaking crescendo-decrescendo systolic murmur at the right upper sternal border that radiates to both carotid arteries. A phonocardiogram and a carotid pulse tracing are shown. Which of the following is the most likely diagnosis?

IncorrectThe answer is B

Explanation

Aortic stenosis

KeepThe later the murmur peaks, the more severe the stenosis.

Three findings point the same way: a late-peaking systolic murmur at the right upper sternal border that radiates to the carotids, a delayed and diminished carotid upstroke (pulsus parvus et tardus), and exertional symptoms. Together they describe fixed left ventricular outflow obstruction.

  • AHypertrophic cardiomyopathy: loudest at the left sternal border, louder with Valsalva, does not radiate to the carotids, and the carotid upstroke is brisk, not delayed.
  • CMitral regurgitation: holosystolic, loudest at the apex, radiates to the axilla.
  • DPulmonic stenosis: a systolic ejection murmur loudest at the left upper sternal border that does not radiate to the carotids.
  • EAortic regurgitation: a diastolic decrescendo murmur with a wide pulse pressure.

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UWorld Step 1 QBank·412 used · 68% correctSample

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