Aortic Stenosis Obstruction to outflow is most commonly localized to the aortic valve. However, obstruction may also occur above or below the valve.

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etiology

Aortic Stenosis Etiology Congenital Unicuspid produce severe obstruction in infancy and is fatal Bicuspid Valves Occurs in 2% of the population and is the most common congenital cardiac defect in the adult Presents with stenosis earlier in life Abnormal architecture leads to turbulent flow and fibrosis

Normal and Congenital Valves Tricuspid Valve Unicuspid Valve Bicuspid Valve

Aortic Stenosis Etiology Acquired Rheumatic Results from adhesion and fusion of the commissures and cusps leading to retraction and stiffening of the free borders with calcific nodules The valve is often regurgitant as well, and is often accompanied by evidence of MV involvement Degenerative (Senile) The cusps are immobilized by a deposit of calcium along the flexion lines in their bases

Rheumatic and Calcified Valves Calcific Bicuspid Valve Rheumatic Valve Calcific Tricuspid Valve

Mixed Valves Congenital Bicuspid Valve affected by Rheumatic Disease and Calcification Tricuspid Valve with Rheumatic Disease creating a functional bicuspid valve, and calcification

Aortic Stenosis Clues to diagnosis Aortic Regurgitation Isolated AS or MV involvement with calcification Rheumatic under 70 yrs. Old over 70 yrs. Old bicuspid valve senile degeneration

Aortic Stenosis Pathophysiology Outflow obstruction Outflow Resistance Concentric Hypertrophy Maintain CO & SV LV Compliance Diastolic Pressure Enhanced LA contraction Maintain LV filling S4

Aortic Stenosis Clinical Manifestations History Angina Occurs in 2/3 of patients with critical AS Half of the patients have normal coronaries Results from increased oxygen demand by a hypertrophied myocardium and decreased oxygen delivery secondary to compression of the vessels Average survival is 5 years

Aortic Stenosis Clinical Manifestations History Syncope Due to reduced cerebral perfusion May be orthostatic, exertional, medication related (nitrates, diuretics, etc.), or due to arrhythmias Average survival is 3 years

Aortic Stenosis Clinical Manifestations History Heart Failure Manifest as orthopnea, dyspnea, PND, pulmonary edema Average survival is 1 – 2 years

Aortic Stenosis Clinical Manifestations Physical Examination Venous System Venous pulse configuration and pressure are unremarkable in well compensated AS An increased A wave may occur as a result of decreased RV compliance secondary to LVH (Bernheim effect)

Aortic Stenosis Clinical Manifestations Physical Examination Carotid Arterial Pulse The classic arterial pulse is called pulsus parvus et tardus (slow and late) Precordium The apical impulse has a sustained lift There is little or no leftward displacement of the PMI

Aortic Stenosis Clinical Manifestations Physical Examination Auscultation S1 – usually normal, may be soft if CHF present S2 – the intensity of A2 decreases as the valve stiffens S2 splitting – with prolongation of LV ejection time A2 will occur later than P2 and cause paradoxical splitting of S2

Aortic Stenosis Paradoxical Splitting A P Inspiration Expiration

Aortic Stenosis Clinical Manifestations Physical Examination S3 – usually not a normal finding in aortic stenosis, it’s presence suggests LV dysfunction S4 – is usually present and suggests LV hypertrophy and decreased LV compliance Ejection click occurs when the leaflets abruptly halt after maximal upward excursion and imply a mobile valve. It disappears as the valve becomes severely calcified.

Murmur of Aortic Stenosis Heard best at the 2nd RICS radiating to the carotids, sometimes throughout the precordium. S4 S 1 S 2

Aortic Stenosis Severity Mild Moderate Severe

x-ray

ekg

Normal Tricuspid Valve tee Calcified Valvular Stenosis

Echocardiogram of Aortic Valve

Doppler Evaluation of the Valve

Catheterization of the Aortic Valve

Aortic Stenosis Natural History Symptomatic Patients Angina = 5 year Syncope = 3 year CHF = 1-2 years Asymptomatic Patients 4% risk of sudden death

Aortic Stenosis Medical Management All patients should follow SBE prophylaxis guidelines Avoid vigorous exercise Use nitrates and diuretics with caution Asymptomatic patients should report the onset of any symptoms promptly

Prosthetic Valves

Prosthetic Valves

Aortic Stenosis Surgical Management

Aortic Stenosis Valvuloplasty

Aortic Regurgitation