Aortic Regurgitation

🫀 Aortic Regurgitation (AR, “Aortic Incompetence”) = backward flow of blood from the aorta into the LV during diastole due to valve malcoaptation. ➡️ Produces LV volume overload, eccentric hypertrophy, and progressive dilatation. ⚡ Chronic AR develops insidiously, whereas acute AR is catastrophic (flash pulmonary oedema + cardiogenic shock).

📖 About

• Prevalence lower than AS but important in younger patients and those with connective tissue disease.
• Pathophysiology: volume overload → eccentric LV hypertrophy → progressive dilatation → eventual systolic dysfunction + heart failure.
• In severe AR, the regurgitant jet can impair coronary perfusion → exertional angina even with normal coronaries.

🫀 Anatomy

• Normal valve: 3 cusps (left coronary, right coronary, non-coronary).
• Sinuses of Valsalva ensure coronary filling in diastole.
• Effective cusp coaptation during diastole prevents regurgitation.

🧬 Aetiology

• Valve leaflet pathology OR aortic root dilatation → incomplete closure.
• Acute AR: LV has no time to adapt → pulmonary oedema + shock.
• Chronic AR: LV adapts with eccentric hypertrophy but decompensates over time.

⚠️ Causes

🩺 Clinical Features

• Acute AR: Severe dyspnoea, hypotension, flash pulmonary oedema, shock.
• Chronic AR: Asymptomatic for years → then exertional dyspnoea, orthopnoea, palpitations, angina, heart failure.
• Murmur: High-pitched, early diastolic “blowing” murmur, left sternal edge, louder on sitting forward in expiration.
• Pulse: Wide pulse pressure; collapsing “water-hammer” (Corrigan’s) pulse.

👨‍🏫 Eponymous Signs

• Austin Flint: Mid-diastolic rumble (regurgitant jet hits mitral leaflet).
• Corrigan:A jerky carotid pulse characterised by full expansion followed by quick collapse. Bounding “water hammer” pulse.
• Quincke: Capillary pulsations in nailbed.
• De Musset: Head bobbing with each beat.
• Traube: “Pistol shot” femoral sounds.
• Hill’s Sign: Popliteal cuff systolic pressure exceeding brachial cuff systolic pressure by more than 20 mmHg. A difference of 20-39 mmHg indicates mild AR. A difference of 40-59 mmHg indicates moderate AR. A difference of 60 mmHg or more indicates severe AR.
• Landolfi's sign Alternating dilatation and constriction of pupil synchronous with cardiac cycle
• Muller's sign Pulsations of the uvula
• Lighthouse sign Capillary pulsations on the forehead and face resulting in alternate blanching and flushing
• Rosenbach's sign pulsations of the liver
• Gerhardt's sign Pulsations of an enlarged spleen >li>Mayne sign More than a 15-mmHg decrease in diastolic blood pressure with arm elevation from the value obtained with the arm in the standard position
• Becker sign Accentuated retinal artery pulsations

🧪 Investigations

• Bloods: FBC, CRP, blood cultures (if IE suspected).
• CXR: Cardiomegaly, LV dilation, ± dilated ascending aorta. Enlargement of the left ventricle, with ‘duckback’ shape of left border.
• ECG: Left ventricular hypertrophy, with diastolic overload pattern in severe AR, conduction delay, ischaemia.
• Echocardiography: is vital for examining aortic valve, determining size of aortic root and assessing LV func tion. Aetiology of AR can thus be established. Severity of regurgitation can be established from Colour Doppler study.
• Cardiac MRI: Best for regurgitant volume & root dimensions.
• Cardiac catheterisation: Coronary anatomy pre-surgery. Cardiac catheterisation and aortography: in assessing the severity of regurgitation, aortic dilatation and the presence of coexisting coronary artery disease.
• Blood – Treponemal serology and determination of inflammatory indices in patients with aortic wall disease.

⚡ Complications

• Progressive LV failure & pulmonary oedema.
• Acute decompensation (endocarditis/dissection).
• Aortic aneurysm or rupture (root disease).
• Sudden death (arrhythmia, shock).

💊 Management

• 👀 Medical: – Vasodilators (ACEi, nifedipine, hydralazine) to reduce afterload. – Digoxin for AF rate control, diuretics, salt restriction and fluid restriction – Avoid β-blockers in acute AR (slows HR → worsens regurgitation). – Serial echo surveillance for LV function (EF, LVEDD, LVESD).
• 🔪 SAVR (surgical valve replacement): Definitive. Indications: any symptomatic severe AR; asymptomatic with EF <50%, LVESD ≥50 mm, or LVEDD ≥70 mm. 🩻 TAVI/TAVR: Not yet standard for isolated AR, but emerging role in high-risk cases. 🚨 Emergency surgery: Acute severe AR (endocarditis or dissection).

✂️ Indications for Surgery (Key Rules)

• Any symptomatic severe AR.
• Asymptomatic with LVEF <50%.
• Severe AR + LVESD ≥50 mm (“rule of 50”).
• Marfan/CTD with root dilatation >50 mm.

📊 Prognosis

• Asymptomatic + normal LV → excellent prognosis with monitoring.
• Once symptomatic or LV dysfunction develops → poor outlook unless surgically corrected.
• Timely valve replacement restores near-normal life expectancy in most.

📚 References

• 2017 ESC/EACTS Guidelines
• AHA/ACC Guidelines 2020
• Otto CM, NEJM 2020: “Aortic Regurgitation and Its Management.”