Aortic regurgitation

Overview

•Early diastolic murmur - high-pitched, blowing; best heard at left lower sternal border (3rd-4th ICS), patient sitting forward, leaning forward, breathing out

•Murmur loudest at right sternal border suggests aortic root dilatation (e.g. Marfan's, ascending aortic aneurysm)

•Austin-Flint murmur - mid-to-late diastolic rumble at apex in severe AR; mimics mitral stenosis but no pathological mitral valve

•Collapsing (water hammer) pulse - forceful beat with rapid collapse; wide pulse pressure (elevated systolic, reduced diastolic)

•Displaced apex beat - laterally and inferiorly, due to LV dilatation

•Chronic AR symptoms - exertional dyspnoea (earliest), orthopnoea, PND, angina (even without CAD - reduced diastolic coronary perfusion), palpitations, fatigue

•Acute AR symptoms - cardiogenic shock, acute pulmonary oedema, tachypnoea; eponymous signs often attenuated

Investigations

🥇 First-line

•Transthoracic echocardiography - confirms diagnosis, quantifies severity via colour Doppler, assesses LV dimensions (LVEDD, LVESD) and ejection fraction; guides surgical timing

•ECG - may show LV hypertrophy/strain; CXR - cardiomegaly (chronic) or pulmonary oedema (acute)

🥈 Second-line

•Cardiac MRI - best for quantifying regurgitant fraction; useful when echo inconclusive or to assess aortic root in Marfan's/bicuspid aortic valve

Differential Diagnosis

Diastolic murmur differentials
FeatureAortic regurgitationMitral stenosisPulmonary regurgitation
Murmur typeEarly diastolic, blowingMid-diastolic rumble + opening snapEarly diastolic (Graham-Steell)
LocationLeft lower sternal border (3rd-4th ICS)ApexLeft upper sternal edge
Pulse pressureWideNormal/narrowNormal
Eponymous signsPresent (De Musset's, Corrigan's, etc.)AbsentAbsent

Feature	Aortic regurgitation	Mitral stenosis	Pulmonary regurgitation
Murmur type	Early diastolic, blowing	Mid-diastolic rumble + opening snap	Early diastolic (Graham-Steell)
Location	Left lower sternal border (3rd-4th ICS)	Apex	Left upper sternal edge
Pulse pressure	Wide	Normal/narrow	Normal
Eponymous signs	Present (De Musset's, Corrigan's, etc.)	Absent	Absent

Management

•Aortic dissection causing AR: IV labetalol - target SBP 100-120 mmHg, HR <60 bpm as bridge to urgent cardiothoracic surgery

•Chronic symptomatic AR or LV dysfunction/dilatation at surgical threshold: aortic valve replacement

•Blood pressure optimisation: ACE inhibitor in chronic AR with hypertension or LV dilatation approaching thresholds

🚨
In aortic dissection with AR, do NOT use vasodilators alone - the underlying dissection requires definitive surgical repair. IV labetalol is given as a bridge to surgery.

Eponymous Signs

Eponymous signs of AR (all reflect wide pulse pressure / hyperdynamic circulation)
De Musset's sign - head nodding with each heartbeat
Quincke's sign - nailbed capillary pulsation on light pressure
Corrigan's sign - visible exaggerated carotid pulsation ('dancing carotids')
Traube's sign - 'pistol shot' over femoral artery
Duroziez's sign - diastolic femoral bruit with gentle pressure over femoral artery
Muller's sign - uvular pulsation with each heartbeat

🎯
De Musset's sign (head nodding) + early diastolic murmur = aortic regurgitation. All eponymous AR signs reflect the wide pulse pressure. Aortic stenosis, mitral regurgitation, and aortic sclerosis all produce systolic murmurs; mitral stenosis produces a mid-diastolic rumble but no AR eponymous signs.