Cardiology > Aortic Regurgitation

   Background 

Aortic regurgitation (AR), also known as aortic insufficiency, is the backflow of blood from the aorta into the left ventricle during diastole 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, while acute AR is a medical emergency. 

II) Classification or Types 

By Chronicity: 

• • Chronic AR: Gradual LV dilation and eccentric hypertrophy; symptoms develop late. 

• • Acute AR: Sudden volume overload without compensatory remodeling; causes cardiogenic shock and pulmonary edema. 

By Etiology: 

• • Valve Leaflet Abnormalities: 

• • Bicuspid aortic valve 

• • Rheumatic heart disease 

• • Infective endocarditis 

• • Myxomatous degeneration 

• • Aortic Root Disease: 

• • Aortic aneurysm or dissection 

• • Marfan syndrome 

• • Ehlers-Danlos syndrome 

• • Syphilitic aortitis 

• • Ankylosing spondylitis 

III) Epidemiology 

• • Sex: More common in males 

• • Age: Chronic AR usually presents in middle to older age; acute AR can occur at any age 

• • Geography: Rheumatic AR more common in low-income countries; aortic root dilation more common in developed regions 

• • Comorbidities: Associated with connective tissue disorders and hypertension 

  Etiology

I) What Causes It 

Chronic Causes: 

• • Bicuspid aortic valve 

• • Rheumatic fever 

• • Connective tissue disorders (e.g., Marfan, Ehlers-Danlos) 

• • Aortic root dilation (hypertension, syphilis, cystic medial necrosis) 

Acute Causes: 

• • Infective endocarditis 

• • Aortic dissection 

• • Chest trauma 

• • Post-valvotomy or TAVR complications 

II) Risk Factors 

• • Congenital bicuspid valve 

• • History of rheumatic fever 

• • Hypertension 

• • Connective tissue disease 

• • Aortic root disease 

• • Endocarditis risk (IV drug use, prosthetic valve, poor dental hygiene) 

   Clinical Presentation

I) History (Symptoms) 

Chronic AR: 

• • Often asymptomatic for years 

• • Progressive exertional dyspnea 

• • Orthopnea and PND 

• • Fatigue, decreased exercise tolerance 

• • Palpitations (increased stroke volume) 

• • Angina (even without CAD) 

• • Awareness of heartbeat (especially in lying position) 

Acute AR: 

• • Sudden onset severe dyspnea 

• • Pulmonary edema 

• • Hypotension and signs of shock 

• • Chest pain (especially with dissection) 

II) Physical Exam (Signs) 

Vital Signs: 

• • Wide pulse pressure (e.g., BP 160/50) 

• • Tachycardia (especially in acute AR) 

Cardiac Exam: 

• • Early diastolic decrescendo murmur best heard at left sternal border (2nd–4th ICS) 

• • Austin Flint murmur: low-pitched mid-diastolic rumble at apex (due to AR jet hitting mitral leaflet) 

• • S3 gallop: with LV dysfunction 

• • Hyperdynamic apical impulse, displaced laterally 

Peripheral Signs (due to high stroke volume): 

• • Corrigan pulse (water-hammer pulse) 

• • De Musset sign (head bobbing) 

• • Quincke’s sign (capillary pulsation in nails) 

• • Traube’s sign (pistol-shot femoral sounds) 

• • Duroziez sign (systolic/diastolic murmur over femoral artery) 

Pulmonary: 

• • Crackles (especially in acute AR) 

  Differential Diagnosis (DDx)

• • Aortic stenosis with regurgitant component 

• • Mitral regurgitation 

• • Tricuspid regurgitation 

• • Patent ductus arteriosus 

• • Ventricular septal defect 

• • Hypertrophic cardiomyopathy 

• • Heart failure with preserved ejection fraction (HFpEF) 

  Diagnostic Tests

Initial Tests: 

Transthoracic Echocardiogram (TTE): 

• • Determines AR severity (jet width, vena contracta, regurgitant volume) 

• • Evaluates LV size and function 

• • Aortic root dilation 

Transesophageal Echocardiogram (TEE): 

• • Useful in endocarditis or if TTE suboptimal 

Electrocardiogram (ECG): 

• • Left ventricular hypertrophy (LVH) 

• • Left axis deviation 

Chest X-ray: 

• • Cardiomegaly (chronic AR) 

• • Pulmonary edema (acute AR) 

• • Aortic root dilation 

BNP/NT-proBNP: 

• • May be elevated with LV dysfunction or heart failure 

Cardiac MRI: 

• • Quantifies regurgitant fraction and volume 

• • Evaluates aortic root and LV 

Cardiac Catheterization: 

• • Coronary assessment before valve surgery 

• • Confirms severity when noninvasive data is inconclusive 

  Treatment

I) Medical Management: 

Chronic AR (asymptomatic): 

• • Afterload reduction with ACE inhibitors, ARBs, or nifedipine (if LV dilation) 

• • Monitor LV function and size 

Symptomatic or Severe AR: 

• • Heart failure management: diuretics, vasodilators 

• • Avoid beta-blockers in aortic root dilation if Marfan syndrome suspected 

Acute AR: 

• • Medical emergency; initiate vasodilators (e.g., nitroprusside) and inotropes 

• • Avoid beta-blockers (worsen bradycardia) 

• • Urgent surgical intervention 

II) Interventional/Surgical: 

Indications for Aortic Valve Replacement (AVR): 

• • Symptomatic severe AR (Class I) 

• • Asymptomatic with LVEF <55% 

• • Asymptomatic with LVESD >50 mm or LVEDD >65 mm 

• • Undergoing other cardiac surgery 

Surgical AVR: 

• • Preferred for low surgical risk candidates 

TAVR (Transcatheter AVR): 

• • Off-label use for AR; reserved for high-risk patients in some centers 

 Patient Education, Screening, Vaccines

• • Importance of symptom reporting (dyspnea, fatigue, palpitations) 

• • Routine follow-up and imaging 

• • Avoid isometric exercises in severe AR 

• • Dental hygiene to reduce endocarditis risk 

Vaccinations: 

• • Annual influenza vaccine 

• • Pneumococcal vaccine 

• • COVID-19 vaccine 

  Consults/Referrals

• • Cardiology: For diagnostic confirmation and medical optimization 

• • Cardiothoracic Surgery: For surgical AVR evaluation 

• • Infectious Disease: If infective endocarditis suspected 

• • Genetics: For patients with connective tissue disorders (e.g., Marfan) 

• • Primary Care: Comorbidity management 

  Follow-Up

• • Echocardiography: 

• • Mild AR: every 3–5 years 

• • Moderate AR: every 1–2 years 

• • Severe AR (asymptomatic): every 6–12 months 

• • Monitor: 

• • LV size and systolic function 

• • Symptoms progression 

• • Blood pressure control 

• • Reevaluate for surgical indication