Aortic Regurgitation Flashcards
What are the signs/examination findings of aortic regurgitation? (6)
* denotes severe
A. Pulse
- Bounding, collapsing pulse
- Severe: *Wide pulse pressure
B. AR signs (refer AR signs card)
C. Apex beat - *deviated, thrusting
D. Heart Sound and Murmur
- Early diastolic murmur (EDM) over LLSE (valvular) vs RSE (aortic root)
- +/- ESM from functional or concomitant AS
- *Soft S2 (A2)
- *Third heart sound (S3)
- *Long duration of diastolic murmur
- *Austin Flint murmur (functional MDM at apex) - due to regurgitant jet striking MV anterior leaflet, obstructing flow from LA into LV
E. Manoeuver to lean forward, expiration
F. Signs of complications
- *Pulmonary hypertension
- *Heart failure
What are the characteristic signs in AR?
- Collapsing pulse
- Brachial dance
- Quickne - visible capillary pulsation in nail bed
- Corrigan - visible carotid pulsation in neck
- De Musset - head nodding with heart beat
- Mullet - uvula systolic pulsation
- Duroziez - femoral compression produces to/fro murmurs
- Traube (pistol shot) - booming sound over femoral arteries
- Hill - higher SBP in leg compared to arm
Describe this heart sound
Early diastolic murmur - AR
Differential diagnosis of diastolic murmur? (5)
(copied from MS - differentials of diastolic murmur)
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AR, atrial myxoma, thrombus, severe MR, MS
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- Austin flint murmur (severe AR)
- Left atrial mass (atrial myxoma)
- Left atrial thrombus (ball-valve thrombosis)
- Severe mitral regurgitation (increased flow through mitral valve during diastole)
- Mitral stenosis
- Flow across tricuspid valve in ASD
- Cor triatriatum - congenital defect with 3 atria divided by fibromuscular band
What are the causes of aortic regurgitation? (min 7)
- Acute, chronic (M: AIR CARS C:RARMH)
Congenital (bicuspid), Marfan, rheumatic, aortic dissection, CTD, SoV rupture, syphilis
Acute
Aortic dissection
Infective endocarditis (valvular)
Rupture of sinus of valsalva aneurysm
Chronic
Congenital: bicuspid aortic valve, VSD with aortic cusp prolapse
Aortitis
Rheumatic fever/heart disease (valvular - co-exist AS)
Syphilis (tertiary) (used to be no. 1 cause 200 years ago)
Connective tissues diseases (aortic root dilatation)
- Acquired: RA, AS, Reiter
- Congenital: Marfan
Hypertension
What is your expected findings on taking BP in AR?
- Wide pulse pressure
- Severe hypertension
- LL > UL SBP discrepancy (Hill’s sign)
How would you investigate a patient with aortic regurgitation?
- ECG (2), CXR (5), TTE, complete workup
ECG
- LVH with diastolic overload (deep narrow Q, ST-d, TWI in left leads)
- LBBB in late disease
CXR
- Calcified valve
- Cardiomegaly
- Widened aorta
- Pulmonary congestion
- Prominent pulmonary arteries
TTE
- Assess valve, establish cause and severity of AR
- Left ventricular size and function
- Complications
Coronary angiography: coronary artery disease
CT or cMRI: assess aortic root and ascending aorta
What are the complications of AR? (2)
- Left heart failure
- Infective endocarditis
How would you manage a patient with aortic regurgitation?
- Education
- Antibiotics prophylaxis
- Treat underlying cause
- Treat complications of CCF, IE
- Vasodilators if severe AR and LV dilatation: ACEi, CCB
- Consider for valve replacement *see indication
What are the types of surgery available for AR?
What is the operative mortality rate of AR?
- Transcatheter aortic valve implantation (TAVI) for non-surgical candidates
- Primary surgical repair - only torn/perforated leaflet
- Valve sparing aortic root reconstruction (David procedure)
- Aortic valve replacement
Operative mortality risk
2% isolated AVR
3.6% AVR + coronary artery bypass
What are the indications for aortic valve replacement in AR?
- Symptomatic - CCF, angina, severe AR
- LV dilatation: LV ESD > 55mm or LV EDD > 65mm
- Aortic root dilatation > 55mm
- Resting LVEF < 55%, exercise LVEF reduction >5%
What is the prognosis of AR?
Annually 4% develop symptoms or CCF
What are the causes of collapsing pulse?
Cardiac related
1. AR
2. PDA
3. Aortopulmonary window
4. Ruptured aortic sinus aneurysm
5. Severe bradycardia
6. Severe MR
Hyperdynamic circulation
7. Paget’s disease
8. High fever
9. Severe anaemia
10. Pregnancy
11. Thyrotoxicosis
How do you differentiate Austin Flint murmur of AR from MS?
MS
1. Opening snap
2. Loud S1
3. Tapping apex beat, not displaced
Pathophysiology of AR
Chronic AR
1. In severe AR, volume of regurgitant flow may be equal to effective forward stroke volume
- Compensatory LV dilation and eccentric hypertrophy to eject larger stroke volume
2. Eventual compensatory failure - LV function deteriorates with reduced stroke volume and EF
3. Myocardial ischaemia - increased oxygen requirement by LV dilation, hypertrophy and systolic tension, with compromised coronary blood flow
4. Failure of cardiac output to rise during strenous activities
Acute
1. LV unprepared for regurgitant volume load, leading to reduced compliance, rising diastolic pressures, pushing mitral valve to close prematurely
