Severe Aortic Regurgitation with Left Ventricular Dysfunction
A 60-year-old man reports 6 months of exertional dyspnoea. He has a collapsing pulse, blood pressure 160/45 mm Hg, an early diastolic murmur at the left upper sternal border, and bilateral fine basal crackles. Echocardiography shows severe aortic regurgitation with a left ventricular ejection fraction of 40%. Which of the following is the most appropriate treatment?
- A.Loop diuretic therapy
- B.Calcium channel blocker therapy
- C.Aortic valve replacementCorrect
- D.ACE inhibitor therapy
Explanation
This patient has severe chronic aortic regurgitation that has become symptomatic and has produced left ventricular systolic dysfunction, which together form a Class I indication for aortic valve replacement in both the ACC/AHA and ESC valvular heart disease guidelines. Chronic regurgitation imposes combined volume and pressure overload, causing eccentric hypertrophy and progressive dilatation; once the ventricle can no longer compensate, ejection fraction falls, symptoms appear, and irreversible myocardial damage begins. Surgery is indicated for symptomatic severe regurgitation regardless of ejection fraction, and for asymptomatic patients when ejection fraction is 55% or less or the left ventricle is markedly dilated, because operating before irreversible remodelling preserves long-term survival. The examination findings all reflect the wide pulse pressure of severe regurgitation: a collapsing Corrigan pulse, a systolic pressure of 160 mm Hg with a diastolic of 45 mm Hg, and the early diastolic murmur best heard at the left sternal border. Basal crackles indicate pulmonary congestion from decompensation. Diuretics relieve congestion and are useful as a bridge but do not change the natural history. Vasodilator therapy with an ACE inhibitor or dihydropyridine may modestly reduce afterload in patients with hypertension or those unfit for surgery, but it must not delay valve replacement when surgical criteria are met. Non-dihydropyridine calcium channel blockers are negatively inotropic and hazardous in reduced ejection fraction.
Why each option
- A.
- Diuretics relieve pulmonary congestion but do not alter progression or improve survival in severe aortic regurgitation.
- B.
- Calcium channel blockers offer no survival benefit and negatively inotropic agents are harmful in reduced ejection fraction.
- C.
- Correct. Symptomatic severe aortic regurgitation is a Class I indication for valve replacement regardless of ejection fraction.
- D.
- ACE inhibitors reduce afterload and help patients unfit for surgery or with hypertension, but should not substitute for indicated valve surgery.
Reference: ACC/AHA 2020 Guideline for the Management of Patients With Valvular Heart Disease
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