Aortic Regurgitation

Scenarios: Shortness of breath, angina, syncope, dyspnoea.

Examination of aortic regurgitation: On general inspection take note of any features that indicate an underlying connective tissue disorder or rheumatological disease. Look at the hands for Quincke’s sign and asses for a collapsing pulse. Inspect inside the mouth for the pulsating uvula of Muller’s sign, and check if the head is bobbing as part of De Musset’s sign. Looking at the neck, asses for prominent carotid pulsations suggestive of Corrigan’s sign. Feel for the displaced apex. Auscultate for an early diastolic murmur heard loudest at the lower left sternal edge in expiration. Check for additional features including heart failure (raised jugular venous pressure, 3rd heart sound, bi-basal crepitations, peripheral oedema) and infective endocarditis (see below). If you are confident about the diagnosis and wish to elicit further features, proceed to check for Durozier’s sign (systolic murmur over femorals with proximal compression and diastolic murmur with distal compression) and Traube’s sign (pistol-shot femorals with systolic and diastolic sounds).

Classic cases:

• Connective tissue disorders: Marfan’s (tall, arachnodactyly, hypermobility, high arched palate), ehlers danlos (hypermobility, hyperextensible skin, fish mouth scars), psuedoxanthoma elasticum (plucked chicken skin appearance at the neck, axillae and antecubital fossae), osteogenesis imperfecta (blue sclerae though these can be seen in the other three conditions as well, bony deformities from prior poor healing of fractures).
• Ankylosing spondylitis: Exaggerated thoracic kyphosis and loss of lumbar lordosis with compensatory extension of the neck and limited neck movements. If found, tell the examiner that you would like to enquire about features of inflammatory joint pain and uveitis, auscultate the lung apices for fibrosis and dipstick the urine for proteinuria of amyloidosis.
• Infective endocarditis: Splinter haemorrhages, clubbing, leukonychia, oslers nodes, janeway lesions, pale palmar creases, conjunctival pallor, long lines for antibiotics, fever, evidence of previous surgery.
• Syphilis: Argyll robertson pupil (small, irregular, depigmentation of the iris, accommodates but does not react to light).
• Mixed valve disease: Listen for an accompanying ESM radiating to the carotids of aortic sclerosis. If this is the case you will need to decide which is the predominant lesions and bear in mind that even if the absence of a stenotic valve you can get a flow murmur across the aortic valve in the presence of regurgitant valves. The latter would not radiate and gives a “to-and-fro” quality to the sound.

Differential diagnosis:

There is a similar murmur in pulmonary regurgitation either as a primary phenomenon or as a Graham Steell murmur secondary to pulmonary hypertension. The differential for an underlying cause of aortic regurgitation is:

• Degenerative: Bicuspid valves, age and factors like hypertension.
• Infective: Infective endocarditis, rheumatic fever, tertiary syphilis.
• Rheumatological: HLA B27 associated arthopathies like ankylosing spondylitis.
• Connective tissue disorders: Marfans, ehlers danlos, psuedoxanthoma elasticum, osteogenesis imperfecta.

If acute, think of dissection, infective endocarditis and prosthetic valve failure.

Investigations:

• Bedside tests: Blood pressure (looking for a wide pulse pressure) and ECG (conduction blocks, LVH criteria), and then for features of infective endocarditis with temperature, urine dipstick (haematuria, proteinuria), and fundoscopy (Roth spots, Becker’s sign of retinal pulsations).
• Bloods: FBC (anaemia, inflammatory markers), CRP/ESR (raised in infective endocarditis), treponemal tests (specific like EIA or TPHA, and non-specific like the VDRL and RPR).
• Imaging: Chest radiograph (pulmonary oedema, pleural effusions, kerley B lines), echocardiogram (left ventricular function, valve anatomy, aortic root size, vegetatios).
• Special tests:

Management:

• Non-pharmacological: Education.
• Medical: Manage co-existing heart failure, manage underlying cause (e.g.: antibiotics for infective endocarditis, penicillin for syphilis).
• Surgical: Aortic valve replacement (biological or mechanical).

Questions:

1. What might be the explanation if you heard a mid-diastolic murmur at the apex in a patient in whom you suspect aortic regurgitation? Austin flint murmur.
2. What is the differential diagnosis of Corrigan’s sign? Corrigan’s sign occurs because you are visually seeing the collapsing pulse within the carotid arteries and can be seen patent ductus arteriosus and other causes of a hyper dynamic circulation (e.g.: sepsis, thyrotoxicosis, anaemia). A rarer cause of prominent pulsations here is due to collateral flow in co-arctation of the aorta. Large pulsations within the jugular venous system can mimic this such as the large CV waves in tricuspid regurgitation, cannon A waves in heart block and giant A waves tricuspid stenosis and restrictive cardiomyopathies. Remember that pulsations within the venous system will not be palpable and can be obliterated by pressure.
3. Which features on examination would make you think that the patient had severe aortic regurgitation? Features of heart failure, wide pulse pressure, and presence of an austin flint murmur, soft S2.
4. What are the indications for valve replacement? Acute aortic regurgitation, symptomatic with heart failure, asymptomatic but aortic root diameter >50mm or left ventricular end-systolic diameter 55mm or ejection fraction <50%.
5. How would you monitor a patient with Marfan’s? Echocardiogram looking at root diameter and valve function, consider eye referral, beta blockers to prevent aortic root widening, then annual echocardiogram surveillance following that with surgical referral for aortic valve replacement and aortic root repair (when root >5cm).
6. What are the specific elements to examining a patient with Marfans? Check how tall they are, ask them to spread their arms out wide to demonstrate disproportionately wide arm span, ask them to place their thumb in their first (it may exceed the ulnar side of the hand) and to wrap their thumb and little finger round their wrist (they will overlap), ask them to look quickly from one side to another to see the shimmering/shaking of the iris (iridonesis) in lens dislocation. Mention relevant additional findings like kyphoscoliosis or chest wall abnormalities.
7. How does homocysteinuria differ from Marfans? Similar phenotype, but inherited autosomal recessively, not associated with aortic root disease, but is associated with learning difficulties and recurrent aortic and venous thromembolic events. In addition, lens dislocation tends to be upwards in Marfans but downwards in homocysteinuria.
8. What is the differential diagnosis of Marfan’s syndrome? Homocysteinuria and MASS syndrome (Mitral valve prolapse, mild non-progressive Aortic root dilatation, Skin and Skeletal manifestations).
9. What is the mode of inheritance of Marfan’s Syndrome? Autosomal dominant with complete penetrance but variable phenotype, due to fibrillin-1 defect, diagnosed using the Ghent criteria.