1) Aortic stenosis is a narrowing of the aortic valve that obstructs blood flow from the left ventricle to the aorta. 2) The most common presenting symptoms are dyspnea on exertion, exertional dizziness, and exertional angina, reflecting the stiff left ventricle's inability to increase cardiac output during exercise. 3) On examination, the carotid pulse is weak and slow rising, and a crescendo-decrescendo murmur is best heard at the right upper sternal border when leaning forward.

1. AORTIC STENOSIS
CLINICAL COMPETENCY
S.R.SRUTHI MEENAXSHI

2. AORTIC STENOSIS
Aortic Stenosis (AS) is narrowing of the
aortic valve resulting in obstruction of
blood flow from the left ventricle to the
ascending aorta during systole.

5. ETIOLOGY

6. Aortic stenosis

7. Williams syndrome

8. PATHOPHYSIOLOGY

9. Symptoms
The classic symptoms due to AS are heart failure(HF), syncope and angina.
However, these “classic” symptoms reflect end stage disease
Now, with earlier diagnosis by echocardiography and prospective followup of patients, the most
common presenting symptom are
1. Dyspnea on exertion or decreased exercise tolerance
2. Exertional dizziness
3. Exertional angina

10. Dyspnea and decreased exercise
tolerance
The most common symptom of AS is dyspnea , usually with exertion
2 factors can contribute : diastolic dysfunction , with an increase in LV filling pressure with exercise
and an inability of LV to increase the CO during exercise because of stiff AV obstructs flow
Systolic LV dysfunction is rare and overt HF is a late end stage finding,usually in who haven’t received
regular medical care .
Once overt HF occurs ,the patient may complain of SOB,easy fatiguability , debilitation and other s/s
of a low CO state.
AF ,which is uncommon in isolated AS ,often accompanies HF

11. Inspection : Carotid Pulse
The quality of the arterial pulse reflects the obstruction to blood flow into the peripheral arterial
circulation
The arterial pulse : as “parvus and tardus “ ie ,it is small or weak and rises slowly
Best appreciated in the carotid artery where the pulse is reduced in amplitude and delayed in
occurrence
The delay can be appreciated by simultaneous palpation of the apex (PMI) and the carotid
artery
There may be an associated carotid artery thrill or coarse vibration (“ shuddering”) due to the
marked turbulence of blood flow across the stenotic valve.

14. PALPATION OF PRECORDIUM
The cardiac impulse at the apex is sustained and is initially normal in location.
However, it becomes displaced late in the course of AS when left ventricular failure occurs
A systolic thrill : at the base of the heart (2nd ICS) ,especially during full expiration with the
patient leaning forward

15. Cardiac Auscultation :Heart sounds
S2: soft and single A2 ( due to AV closure ) is delayed and tends to occur simultaneously with P2
(due to PV closure )
S2 may become paradoxically split when the stenosis is severe and associated with LV
dysfunction
With increasingly severe, fixed AS and A2 closing sound may disappear
The presence of a normal split S2 is the most reliable finding to exclude severe AS in adults

19. The S1 is usually N.
However,an aortic ejection click, which is more commonly heard with congenital bicuspid valve,
may be heard after S1 ( when the leaflets are stiff ,but still somewhat compliant and mobile )
Vigorous LA contraction can lead to a S4

20. AS :Murmur
The hallmark finding is a crescendo – decrescendo ejection murmur ,heard best with the
diaphragm of the stethoscope at the right upper sternal border when a patient is sitting upright
leaning forward
The murmur typically radiates to one or both carotid arteries and has a harsh or grating quality
The intensity of systolic murmur does not correspond to the severity of AS .
The more severe the stenosis, the longer the duration of the murmur and the more likely it
peaks at late systole .

21. In elderly persons with calcific AS ,however the murmur may be more prominent at the apex
,because of radiation of its high frequency components( Gallavardian phenomenon) .
This may lead to its misinterpretation as a murmur of MR
The murmur is soft when stenosis is less severe ,grows louder as stenosis progresses, and
becomes longer and peaks in volume later in systole ( ie crescendo phase becomes longer and
decrescendo phase becomes shorter) as stenosis becomes more severe .

23. As LV contractility decreases in critical AS ,the murmur becomes softer and shorter.
The intensity of the murmur may therefore be misleading in these circumstances .
The murmur of AS typically increases with maneuvers that increase LV volume and
contractility (eg leg raising , squatting , Valsalva release) and decreases LV volume (Valsalva
maneuvers ) or increase afterload (isometric handgrip)

25. A high pitched, diastolic blowing murmur may be present if the
patient has associated aortic regurgitation
Rarely, right ventricular failure with systemic venous
congestion ,hepatomegaly and edema precede LV failure.
This probably due to the bulging of the interventricular septum
into the right ventricle, with impedence in filling ,elevated
jugular venous pressure , and prominent a wave ( Bernheim
effect)

26. Management
Patients with symptomatic severe AS should have prompt AV replacement
Old age is not a contraindication to valve replacement
Aortic balloon Valvuloplasty is useful in congenital aortic stenosis but is of no value in older
patients with calcific aortic stenosis
Anticoagulants are only required in patients who have Afib or those who have had a valve
replacement with a mechanical prosthesis.