Aortic Regurgitation

Key Features

• Rheumatic causes less common since advent of antibiotics

• Nonrheumatic causes predominate

  • Congenitally bicuspid valve

  • Infective endocarditis

  • Hypertension

  • Marfan syndrome

  • Aortic dissection

  • Ankylosing spondylitis

• Rarely atherosclerotic in nature

Clinical Findings

• High-pitched, decrescendo aortic diastolic murmur along the left sternal border; no change with respiration

• Hyperactive, enlarged left ventricle (LV)

• Wide pulse pressure with peripheral signs

  • Water-hammer pulse or Corrigan pulse: rapid rise and fall with an elevated systolic and low diastolic pressure

  • Quincke pulses: pulsatile nail beds

  • Duroziez sign: to and fro murmur over a partially compressed femoral peripheral artery

  • Musset sign: head bob with each pulse

  • Hill sign: leg systolic pressure > 40 mm Hg higher than arm

• Angina pectoris or atypical chest pain may occasionally be present

• Associated coronary artery disease and syncope are less common than in aortic stenosis

• Exertional dyspnea and fatigue are the most frequent symptoms, but paroxysmal nocturnal dyspnea and pulmonary edema may also occur

• Usually slowly progressive and asymptomatic until middle age, although onset may sometimes be rapid, as in infective endocarditis or aortic dissection

Diagnosis

• ECG: LV hypertrophy

• Chest radiograph: Cardiomegaly with LV prominence and sometimes aortic dilation

• Doppler echocardiography

  • Confirms the diagnosis

  • Estimates severity

• Annual echocardiographic assessments of LV size and function are critical in determining the timing of valve replacement when the aortic regurgitation is severe

• CT or MRI

  • Can estimate aortic root size

  • Can exclude ascending aneurysm

• Cardiac catheterization

  • Can help quantify severity

  • Can evaluate the coronary and aortic root anatomy preoperatively

Treatment

• Medications that decrease afterload can reduce regurgitation severity

  • Current recommendations advocate afterload reduction when there is associated systolic hypertension (systolic > 140 mm Hg)

• Angiotensin receptor blockers (ARBs)

  • Preferred over β-blockers as additions to medical therapy in patients with Marfan disease

  • Reduce aortic stiffness (by blocking TGF-beta) and slow the rate of aortic dilation

• Elective surgery is indicated

  • Once aortic regurgitation causes symptoms

  • Before symptoms emerge for those who have an ejection fraction < 50% or increasing end-systolic LV volume

  • For asymptomatic ascending aneurysm indicated when maximal dimension > 5.0 cm (> 4.5 cm in patients with Marfan syndrome)

• Urgent surgery is indicated in acute aortic regurgitation (usually due to endocarditis or dissection)

• Operative mortality is usually 3–5%