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Aortic Regurgitation

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Background #

Aortic regurgitation (AR), also known as aortic insufficiency, is the diastolic backflow of blood from the aorta into the left ventricle due to inadequate closure of the aortic valve. This leads to volume overload of the left ventricle, progressive dilation, and eventually left ventricular systolic dysfunction. Chronic AR develops insidiously over years to decades, while acute AR is a medical emergency requiring urgent intervention.

Classification/Types

By Chronicity:

Chronic AR: Gradual LV dilation and eccentric hypertrophy with compensatory remodeling; symptoms develop late in the disease course.

Acute AR: Sudden volume overload without compensatory remodeling; causes rapid hemodynamic deterioration, cardiogenic shock, and pulmonary edema.

By Etiology:

Valve Leaflet Abnormalities:

  • Bicuspid aortic valve
  • Rheumatic heart disease
  • Infective endocarditis
  • Myxomatous degeneration
  • Degenerative calcific disease

Aortic Root Disease:

  • Aortic aneurysm or dissection
  • Marfan syndrome
  • Ehlers-Danlos syndrome
  • Syphilitic aortitis
  • Ankylosing spondylitis
  • Hypertensive aortopathy

Epidemiology

Aortic regurgitation is the third most common valvular heart disease.[1] The prevalence of any AR in the Framingham Heart Study was 4.9%, with moderate or severe AR occurring in 0.5% of the population.[2,3] AR is more common in men (13.0%) than women (8.5%).[2] The incidence of AR has been reported at 19.7 per 100,000 person-years in men and lower in women.[4]

The prevalence and severity increase progressively with age, peaking in the fourth to sixth decades of life, with AR occurring in approximately 2% of individuals older than 70 years.[5] In developing countries, rheumatic heart disease remains the most common etiology and may present in the second or third decade of life.[6] In industrialized nations, degenerative valve disease, bicuspid aortic valve, and aortic root dilation are the predominant causes, typically affecting older adults with associated comorbidities.[7]

Pathophysiology

The pathophysiology of AR differs markedly between acute and chronic presentations. In chronic AR, diastolic regurgitation of blood from the aorta into the left ventricle causes progressive volume overload. The left ventricle initially adapts through eccentric hypertrophy, in which sarcomeres are laid down in series, elongating myocardial fibers and increasing chamber compliance.[8,9] This compensatory mechanism allows the LV to accommodate the increased end-diastolic volume while maintaining normal filling pressures. Concurrently, the LV develops hypertrophy to normalize wall stress according to the Laplace law, maintaining the normal ratio of wall thickness to cavity radius.[10]

During the early compensated phase, the left ventricular ejection fraction remains normal or even elevated due to increased preload activating the Frank-Starling mechanism.[11] The total stroke volume ejected comprises both the effective forward flow and the regurgitant volume. AR also imposes pressure overload, as systolic hypertension develops from the ejection of both forward and regurgitant volumes into the aorta during systole.[12] The decreased aortic diastolic pressure and elevated systolic pressure result in a characteristically widened pulse pressure.[13]

Over time, when compensatory hypertrophy fails to keep pace with chronic volume overload, end-systolic wall stress increases, leading to LV decompensation with reduced systolic function and heart failure.[14] In acute AR, the sudden volume overload overwhelms a non-dilated, non-compliant left ventricle that cannot rapidly adapt. This causes a precipitous rise in LV end-diastolic pressure, premature mitral valve closure, pulmonary edema, reduced forward stroke volume, and cardiogenic shock.[15,16]

Etiology #

Chronic Causes:

  • Bicuspid aortic valve
  • Rheumatic fever
  • Connective tissue disorders (Marfan syndrome, Ehlers-Danlos syndrome)
  • Aortic root dilation (hypertension, aging, cystic medial necrosis)
  • Degenerative calcific valve disease
  • Syphilitic aortitis
  • Ankylosing spondylitis

Acute Causes:

  • Infective endocarditis
  • Aortic dissection
  • Chest trauma
  • Post-valvotomy or TAVR complications
  • Prosthetic valve dysfunction

Risk Factors

  • Congenital bicuspid aortic valve
  • History of rheumatic fever
  • Systemic hypertension
  • Connective tissue disorders
  • Aortic root disease or aneurysm
  • Risk factors for endocarditis (IV drug use, prosthetic valve, poor dental hygiene)
  • Advanced age

Clinical Presentation #

I) History (Symptoms)

Chronic AR:

  • Often asymptomatic for years to decades
  • Progressive exertional dyspnea
  • Orthopnea and paroxysmal nocturnal dyspnea
  • Fatigue and decreased exercise tolerance
  • Palpitations (from increased stroke volume)
  • Angina pectoris (even without coronary artery disease)
  • Awareness of heartbeat, especially when lying down
  • Nocturnal angina (due to bradycardia-related severe diastolic hypotension)

Acute AR:

  • Sudden onset severe dyspnea
  • Acute pulmonary edema
  • Hypotension and signs of cardiogenic shock
  • Chest pain (especially with aortic dissection)
  • Tachycardia and peripheral vasoconstriction

II) Physical Exam (Signs)

General Exam:

Patients with chronic compensated AR may appear relatively well despite significant valvular disease. In acute AR or decompensated chronic AR, patients appear acutely ill with respiratory distress and signs of shock.

Vital Signs:

  • Wide pulse pressure (e.g., BP 160/50 mmHg in chronic AR)
  • Tachycardia (especially prominent in acute AR)
  • Tachypnea in decompensated states

Cardiac Exam:

  • Early diastolic decrescendo murmur: high-pitched, blowing quality, best heard at left sternal border (2nd–4th intercostal space) with patient leaning forward in end-expiration
  • Austin Flint murmur: low-pitched mid-diastolic rumble at apex (due to AR jet causing functional mitral stenosis)
  • S3 gallop: indicates LV dysfunction
  • Systolic ejection murmur: may be present due to increased flow
  • Hyperdynamic, laterally displaced apical impulse (chronic AR)
  • Soft or absent murmur in acute severe AR despite hemodynamic severity

Peripheral Signs (in chronic AR with high stroke volume):

  • Corrigan pulse (water-hammer pulse): rapid upstroke and collapse
  • De Musset sign: head bobbing with each heartbeat
  • Quincke’s sign: capillary pulsations visible in nail beds
  • Traube’s sign: pistol-shot sounds over femoral arteries
  • Duroziez sign: systolic and diastolic murmur over compressed femoral artery

Pulmonary:

  • Bilateral crackles, especially in acute AR or decompensated heart failure

Differential Diagnosis #

  • Aortic stenosis with regurgitant component (mixed valve disease)
  • Mitral regurgitation
  • Tricuspid regurgitation
  • Patent ductus arteriosus
  • Ventricular septal defect
  • Hypertrophic cardiomyopathy
  • Heart failure with preserved ejection fraction (HFpEF)
  • Pulmonary regurgitation

Diagnostic Testing #

Initial Tests:

Transthoracic Echocardiogram (TTE):[17,18]

  • Determines AR severity using multiple parameters: jet width, vena contracta, regurgitant volume and fraction, effective regurgitant orifice area
  • Evaluates LV size (end-diastolic and end-systolic dimensions/volumes) and systolic function (ejection fraction)
  • Assesses aortic root dimensions
  • Identifies valve morphology and etiology
  • Holodiastolic flow reversal in descending aorta indicates severe AR

Transesophageal Echocardiogram (TEE):

  • Particularly useful when TTE image quality is suboptimal
  • Superior for evaluation of endocarditis (vegetations, abscesses)
  • Better visualization of aortic root and ascending aorta

Electrocardiogram (ECG):

  • Left ventricular hypertrophy with strain pattern
  • Left axis deviation
  • May show signs of LV volume overload

Chest X-ray:

  • Cardiomegaly with LV prominence (chronic AR)
  • Dilated ascending aorta or aortic knob
  • Pulmonary edema (acute AR or decompensated heart failure)

BNP/NT-proBNP:

  • Elevated in heart failure or LV dysfunction
  • May assist in risk stratification and monitoring

Cardiac MRI:[19]

  • Gold standard for LV volume and mass quantification
  • Accurate measurement of regurgitant volume and fraction
  • Assessment of myocardial fibrosis
  • Evaluation of aortic root and ascending aorta dimensions

Cardiac Catheterization:

  • Coronary angiography before valve surgery in patients with coronary disease risk factors
  • Aortic root angiography can confirm AR severity when noninvasive data inconclusive
  • Hemodynamic assessment in selected cases

Treatment #

I) Medical Management:

Chronic AR (Asymptomatic with Normal LV Function):[20,21]

  • Blood pressure control is essential, particularly in patients with hypertension or aortic root dilation
  • Angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin receptor blockers (ARBs) for hypertension
  • Dihydropyridine calcium channel blockers (e.g., nifedipine) may be considered for hypertension
  • Beta-blockers should generally be avoided in severe AR as they prolong diastole and may increase regurgitant volume; however, they are indicated for aortic dissection management
  • Serial echocardiographic monitoring is critical
  • Avoid isometric exercise in severe AR

Symptomatic or Severe AR with LV Dysfunction:

  • Heart failure management: diuretics for volume overload, vasodilators (ACE-I/ARBs) to reduce afterload
  • Medical therapy is a bridge to surgery, not definitive treatment
  • Optimize hemodynamics before surgical intervention

Acute Severe AR:[22]

  • Medical emergency requiring urgent intervention
  • Intravenous vasodilators (e.g., nitroprusside) to reduce afterload
  • Inotropic support if needed (e.g., dobutamine)
  • Avoid beta-blockers (worsen bradycardia and increase regurgitant time)
  • Intraaortic balloon pump is contraindicated (worsens regurgitation)
  • Stabilize hemodynamics while expediting surgical evaluation

II) Interventional/Surgical:

Indications for Aortic Valve Replacement (AVR):[23,24,25]

Class I Indications (Should be performed):

  • Symptomatic patients with severe AR regardless of LV function
  • Asymptomatic patients with severe AR and LVEF ≤50% (ESC/EACTS) or ≤55% (ACC/AHA)
  • Asymptomatic patients with severe AR and LVESD >50 mm or indexed LVESD >25 mm/m²
  • Patients with severe AR undergoing cardiac surgery for another indication

Class IIa Indications (Reasonable to perform):

  • Asymptomatic patients with severe AR and LVEF 50-55% (ACC/AHA: 55-60%)
  • Asymptomatic patients with severe AR and progressive LV dilation (LVEDD >65 mm)
  • Asymptomatic patients with indexed LVESD >20 mm/m² if low surgical risk (ESC/EACTS)

Surgical Aortic Valve Replacement (SAVR):[26]

  • Remains the gold standard treatment for AR
  • Preferred for younger patients, those with low surgical risk, and patients with concomitant ascending aortic disease requiring surgery
  • Mechanical prosthetic valves: recommended for patients <50 years (ACC/AHA) or <60 years (ESC/EACTS); require lifelong anticoagulation
  • Bioprosthetic valves: preferred for older patients or those with contraindications to anticoagulation; require anticoagulation for 3-6 months post-operatively
  • Valve repair may be considered in selected cases with suitable anatomy

Transcatheter Aortic Valve Replacement (TAVR) for AR:[27,28,29]

  • NOT currently approved for isolated native AR in standard-risk patients
  • Conventional TAVR devices designed for aortic stenosis have poor outcomes in pure AR due to lack of annular calcification, large annuli, and risk of valve embolization
  • Dedicated devices for AR (JenaValve Trilogy, J-Valve) showing promising results in high-surgical-risk patients:
    • ALIGN-AR trial: 7.8% 1-year mortality in high-risk AR patients treated with JenaValve Trilogy system
    • Device success rates >90% with dedicated AR devices
    • Phase 3 randomized trial (ARTIST) planned to compare dedicated TAVR device with SAVR
  • May be considered off-label for inoperable high-risk patients at experienced centers
  • Future: dedicated AR devices may expand treatment options for high-risk patients unsuitable for surgery

Consults #

  • Cardiology: Essential for diagnostic confirmation, severity assessment, and medical optimization
  • Cardiothoracic Surgery: For surgical AVR evaluation and timing optimization
  • Interventional Cardiology: For consideration of transcatheter options in high-risk patients
  • Infectious Disease: If infective endocarditis is suspected or confirmed
  • Genetics/Medical Genetics: For patients with suspected or confirmed connective tissue disorders (e.g., Marfan syndrome, Ehlers-Danlos syndrome)
  • Primary Care/Internal Medicine: For cardiovascular risk factor modification and comorbidity management

Patient Education #

Counseling:

Disease-Specific Education:

  • Importance of recognizing and reporting new or worsening symptoms: dyspnea, fatigue, chest pain, palpitations, syncope
  • Understanding the natural history and potential progression of AR
  • Adherence to prescribed medications and follow-up appointments
  • Importance of serial imaging to monitor LV size and function

Activity and Exercise:

  • Avoid isometric exercise (weightlifting, heavy resistance training) in severe AR
  • Regular aerobic exercise as tolerated is generally safe in mild-moderate AR
  • Discuss appropriate activity levels with healthcare provider

Dental Hygiene and Endocarditis Prophylaxis:

  • Maintain excellent oral hygiene to reduce risk of bacteremia
  • Antibiotic prophylaxis before dental procedures is NOT routinely recommended for native valve AR
  • Prophylaxis IS recommended for patients with: prosthetic valves, previous endocarditis, certain congenital heart disease, cardiac transplant with valvulopathy[30]

Screening (USPSTF Recommendations):

The USPSTF does not have specific recommendations for screening for valvular heart disease. However, the following cardiovascular prevention recommendations apply to patients with AR:

Blood Pressure Screening:[31]

  • Screen all adults aged 18 years or older for hypertension
  • Blood pressure control is particularly important in AR patients to reduce afterload and slow aortic root progression

Statin Use for Primary CVD Prevention:[32]

  • Consider statins for adults aged 40-75 years with ≥1 CVD risk factor and 10-year CVD risk ≥10%
  • Particularly relevant for AR patients with additional cardiovascular risk factors

Behavioral Counseling:[33]

  • Offer or refer adults with CVD risk factors to behavioral counseling interventions to promote healthful diet and physical activity
  • All adults: counsel on smoking cessation if applicable

Cardiovascular Risk Assessment:[34]

  • The USPSTF recommends against screening with resting or exercise ECG for CVD risk assessment in asymptomatic adults at low risk (D recommendation)
  • Insufficient evidence for intermediate- or high-risk adults (I statement)

Vaccinations:

The USPSTF defers to the CDC Advisory Committee on Immunization Practices (ACIP) for vaccine recommendations.[35] Patients with AR, especially those with heart failure or preparing for valve surgery, should receive:

  • Influenza vaccine: Annual vaccination recommended
  • Pneumococcal vaccine: As per ACIP schedule based on age and risk factors
  • COVID-19 vaccine: Keep up to date with current recommendations
  • Tetanus-diphtheria-pertussis (Tdap/Td): As per routine schedule

Follow-Up #

Echocardiographic Surveillance:[36,37]

Mild AR:

  • Repeat TTE every 3-5 years if asymptomatic with normal LV size/function

Moderate AR:

  • Repeat TTE every 1-2 years if asymptomatic with normal LV size/function

Severe AR (Asymptomatic):

  • Repeat TTE every 6-12 months
  • More frequent monitoring (every 3-6 months) if LVEF approaching threshold or LVESD/LVEDD increasing

Severe AR with Symptoms or LV Dysfunction:

  • Urgent referral for surgical evaluation

Clinical Monitoring:

  • Regular assessment of symptoms and functional capacity
  • Blood pressure monitoring and optimization
  • Management of cardiovascular risk factors
  • Serial evaluation for surgical indication development
  • Cardiac MRI may be considered for more precise LV volume quantification and assessment of myocardial fibrosis if echocardiographic data are inconclusive
  • Exercise stress testing may provide prognostic information in selected asymptomatic patients

References #

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Updated on November 24, 2025