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Showing posts with label Aortic regurgitation. Show all posts
Showing posts with label Aortic regurgitation. Show all posts

What are the investigation finding in aortic regurgitation

The main modalities of investigations in AR are ECG, chest X-ray, echocardiogram and cardiac catheterisation.
ECG findings in AR
1.    ECG – will show evidence of left ventricular hypertrophy (LVH)
2.    There will be diastolic overload pattern – that is prominent and tall T wave in lateral leads
3.    Increased chance of intraventricular conduction disturbance.
Chest X-ray in aortic regurgitation
1.    CXR reveal cardiomegaly
2.    Dilated – aorta
3.    Calcification of aortic valve or root.
Echocardiography in aortic regurgitation
1.  There is dilated left ventricle
2.  Regurgitant aortic valve can be seen.
3.  There is fluttering of anterior mitral leaflet.
Indication of cardiac catheterisation on AR
          It is routinely done in all patients with aortic regurgitation.

How will you manage a case of aortic regurgitation

Management of aortic regurgitation is both medical and surgical.
1.    Porphylaxis of rheumatic fever and infective endocarditis is given.
2.    Avoid all the precipitating factors.
-          Exertion
-          Anemia
-          Thyroid disease
-          Rheumatic fever
-          Infective endocarditis
-          Arrhythmia
Avoid and correct all these precipitating factors.
3.    Reduce the regurgitation.
          Long acting nifedipine can  increase the heart rate there by decreasing the duration of diastole.
Management of  symptomatic patients
          It include
-          Diuretics
-          ACE inhibitors
-          Digoxin

What is the effect of other cardiac lesions in aortic regurgitation

In this section we will learn about the effect of mitral stenosis, mitral regurgitation, aortic stenosis and cardiac failure on aortic regurgitation.
Effect of mitral stenosis on AR
1. Mitral stenosis will decrease the symptoms of AR
2. There is decrease in length and intensity of early diastolic murmur of AR and masking of peripheral signs of aortic regurgitation.
3. There is increased chance for
·         Atrial fibrillation
·         Pulmonary artery hypertension
4.    Due to co-existent MS – There will be loud S1 and opening snap.
What is the effect of MR on AR
          Mitral regurgitation will decrease the symptoms of AR. It will decrease the length and intensity of EDM of AR and mask the peripheral signs of AR. Due to the coexisting mitral regurgitation there is increased chance for atrial fibrillation and pulmonary artery hypertension.
What is the effect of aortic stenosis on aortic regurgitation
          If the patient has coexisting AS or AR pulse character and pulse pressure may be normal. There will be increased length and intensity of ejection systolic murmur.
What are the effect of cardiac failure on AR
If the patient has coexisting AS or AR pulse character and pulse pressure may be normal. There will be increased length and intensity of ejection systolic murmur.
What are the effect of cardiac failure on AR
In patients with cardiac failure pulse volume decrease and pulse pressure decreases. Early diastolic murmur will become softer and shorter. Ejection systolic murmur and mid diastolic murmur disappears.

Describe the murmurs in aortic regurgitation

Aortic regurgitation produce three type of murmurs
Describe the classical murmur of AR (EDM)
1.    Classical murmur of AR is a high pitched blowing descrendo murmur
2.    Best heard in 2nd aortic area
3.    Patient leaning forward
4.    Breath held in expiration 
Why the murmur of AR is early diastolic in nature
          Because the pressure in aorta is more than left ventricle during early part of systolic, which equalises in the middle part of diastolic .
Frequency of murmur
          It is due to high velocity of flow and due to small regurgitant volume.
Intensity of murmur
Mild AR        - Soft murmur is heard
Severe AR     - loud murmur is heard
These relation need not be true always
Duration of murmur
Mild AR – Murmur is confined to early part of diastole
Severe AR – Murmur is haldiastolic and descrendo in nature
Site of murmur
1.    Normally heard in the 2nd and 3rd right intercostals space.
2.    May be conducted down to lower sternal border.
3.    In AR due to aortic root dilatation, it may be heard down the right sternal border.
4.    In elderly people it may be heard at the apex.
What are the techniques that increases the audibility of murmur
1.    Hand grip
2.    Squatting
3.  Simultaneous application of pressure cuffs to both arms for about 20 seconds to a level of 20mm above the systolic blood pressure.
Why the murmur is early diastolic in severe AR with LV dysfunction
          Severe AR with LV dysfunction produce high left ventricular end diastolic pressure, which decreases the aorta to left ventricular gradient in the later part of diastolic as the murmur will decrease. 
Ejection systolic murmur in AR
          It is produced due to rapid ejection of increased stroke volume through the abnormal valve.
          Even though the murmur may be loud – it need not imply the associated AS.
Austin flint murmur
Mention the causes of absent murmur in AR
Low cardiac output
Cardiac failure
Pulmonary artery hypertension
Other valvular lesion
Mitral stenosis
Mitral regurgitation
Others
COPD
Obesity

Describe the heart sounds in aortic regurgitation

First heart sound (S1)
          Intensity of S1 is usually decreased, it is due to  the partial closure of mitral valve leaflet in presystole. It indicates that the aortic regurgitation is of moderate to severe intensity.
If the  patient has loud S1 – think of coexisting mitral stenosis.



Comment on the A2 in AR
          A2 is usually variable.
          Loud A2 is due to aortic root dilatation.
          Soft A- is produced due to low ability of valve leafet to vibrate after the aortic valve closure.
Describe the split in AR
          Split may be normal, single S2 or prodoxically split. 
What is the significance of S3 in AR
Occur in AR due to increased LVEDV (Left ventricular end diastolic volume). Left ventricular dysfunction can also  cause LVS3. LVS3 is commonly associated with Austin – flint murmur and peripheral signs of aortic regurgitation. 
What is the significance of S4 in AR
          Seen usually in severe AR.
What is the significance of Aortic ejection click in AR
1.    Seen in patients with mild AR with normal LV function.
2.    Valvular Ejection Click – is due to bicuspid aortic valve.
3.    Vascular ejection click– is due to Aortic root dilatation.

What are the symptoms of aortic regurgitation

Aortic regurgitation is a volume overloaded situation. Patients experience the following symptoms.
1.    Palpitation
2.    Exertional dyspnea
3.    Angina
What is the mechanism fo angina in Aortic regurgitation ?

         It is due to the imbalance between myocardial oxygen demand and oxygen supply. There is increased demand due to the left ventricular hypertrophy. Decreased supply is due to decreased coronary artery perfusion gradient. Decreased  coronary artery perfusion gradient is due to increased left ventriocular end diastolic pressure (LVEDP) and decreased aortic diastolic blood pressure.

Surgical management of patients with AR (Aortic regurgitation)

Aortic valve replacement is indicated in
1.    Severe symptomatic AR
2.    Severe AR with echo evidence of left ventricular dysfunction known as 55-55 rule. Surgery is indicated if ejection fraction <55%
3.    Left ventricular end systolic volume >55ml/m2.
(Clink on the image to enlarge)

What are the clinical signs of aortic regurgitation

Aortic regurgitation may produce the following clinical signs
1.    High volume collapsing pulse.
2.    High pulse pressure.
3.    Jugular venous pressure may be normal or raised.
4.    Forceful apex beat.
5.    Diastolic thrill may be present.
6.    Soft S1.
7.    Paradoxic splitting of S2.
8.    Left ventricular S3/S4.
9.    Ejection click may be present.
Loud P2 and left parasternal heave is seen if pulmonary artery hypertension present.
High pitched blowing decrescendo early diastolic murmur may be heard at neoaortic area. It may be conducted down the lower left sternal border.

Peripheral  signs of AR
Aortic regurgitation produce peripheral signs due to volume overload.
1.    Collapsing pulse.
2.    Pulses bisferiens.
3.    Demusset sign.
4.    Corrigan’s sign.
5.    Becker’s sign.
6.    Quincke sign.
7.    Hills sign.
8.    Duroziez sign.
9.    Pistal shot femorals.
10. Mullers sign.
11. Rosen back sign.
12. Gerhat’s sign.

Most important clinical signs are:
-          Collapsing pulse and peripheral signs.
-          Forceful apex.
-          Soft S1.
-          Early diastolic murmur (EDM) in 2nd aortic area.
-          Mid diastolic murmur (MDM) at mitral area.
What is the apex beat in AR
          It is displaced and forceful.
          Undisplaced and forceful in mild to moderate AR.

Describe the palpatory findings in AR
1.   Forceful apex beat.
2.   Diastolic thrill may be present.

What are the causes of AR with absent peripheral signs ?
1.    Mild AR.
2.    Acute AR.
3.    AR with the following
-        Left ventricular dysfunction.
-        Pulmonary artery hypertension.
-        Associated aortic stenosis.
-        Associated mitral valve disease.
-        Hypovolemia.

What is the basis of Duroziez murmur
It is due to the exaggerated reversal of blood flow in diastole.