Aortic Stenosis
A 73-year-old man has exertional dyspnea and two episodes of syncope while walking uphill. A harsh mid-systolic ejection murmur is heard at the right second intercostal space, radiating to both carotids. The carotid upstroke is delayed and low in volume, and the second heart sound is soft. Blood pressure is 112/78 mm Hg. What is the most likely diagnosis?
- A.Aortic regurgitation
- B.Mitral regurgitation
- C.Hypertrophic cardiomyopathy
- D.Aortic stenosisCorrect
Explanation
A crescendo-decrescendo mid-systolic murmur maximal in the right second intercostal space with radiation to the carotids is the signature of left ventricular outflow obstruction at the aortic valve. The supporting findings of pulsus parvus et tardus, a delayed low-amplitude carotid upstroke, a soft or absent aortic component of the second heart sound, and a narrow pulse pressure indicate severe stenosis. The classic symptom triad of angina, syncope, and exertional dyspnoea reflects the fixed obstruction: cardiac output cannot rise with exercise, subendocardial perfusion falls as hypertrophied myocardium raises oxygen demand, and heart failure develops as the ventricle decompensates. Calcific degeneration of a trileaflet valve is the usual cause after age 70, whereas a bicuspid valve presents in the fifth or sixth decade and rheumatic disease accompanies mitral involvement. Aortic regurgitation produces an early diastolic decrescendo murmur with a wide pulse pressure and a collapsing pulse, the opposite of this pulse character. Mitral regurgitation gives a pansystolic apical murmur radiating to the axilla with a normal or brisk upstroke. Hypertrophic obstructive cardiomyopathy also causes a systolic murmur and syncope but the murmur is loudest at the left sternal border, does not radiate to the carotids, has a brisk bifid upstroke, and increases with Valsalva or standing. Echocardiography is the diagnostic test, and symptomatic severe stenosis is an indication for surgical or transcatheter valve replacement.
Why each option
- A.
- Aortic regurgitation gives an early diastolic murmur with a wide pulse pressure and collapsing pulse, not a slow-rising pulse.
- B.
- Mitral regurgitation causes a pansystolic apical murmur radiating to the axilla with a normal carotid upstroke.
- C.
- Hypertrophic cardiomyopathy has a systolic murmur at the left sternal border without carotid radiation, a brisk bifid pulse, and augmentation on Valsalva.
- D.
- Correct. A mid-systolic ejection murmur radiating to the carotids with pulsus parvus et tardus and a soft second heart sound indicates severe aortic stenosis.
Reference: 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease
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