AS

• Congenital abnormality
• Degenerative calcification
• Postinflammatory process (rheumatic)

In isolated valve stenosis, symptoms typically occur when the orifice is reduced to ¼ its normal size.

In mixed stenosis and regurgitation, sx can occur when each is moderate

• Imaging of the valve to determine the etiology
• Quantification of stenosis severity
• Evaluation of coexisting valvular lesions
• Assessment of LV systolic function
• Response of chronic overload on upstream chambers and vascular bed

• Thickened leaflets
• Restricted leaflet motion with lack of normal systolic fluttering
• Narrowed valve orifice

• AI (80%)
• LVH due to pressure overload, leads to increased LVEDP and LAP
• LAE
• Decreased LVSF late in course
• Post-stenotic dilatation of the ascending aorta (follow aorta in the PSLAX or SSN)

• DOE = most common sx of AS
• Sx of LCHF: DOE, dyspnea, cough, orthopnea, paroxysmal nocturnal dyspnea, crackles, fatigue (50%)
• Angina (35%)
• Dizziness/syncope with exertion (15%)
• Right heart failure late in course: JV distention, hepatomegaly, peripheral edema, ascites
• Narrow pulse pressure (decreased SBP)
• Parvus et tardus palpation of RCA

• Muffled S2
• Harsh mid-systolic ejection murmur
• S4 (grunt) with decreased LV compliance

• LV pressures rise much higher than aortic pressure during systole
• Aortic root pressure decreased, curve appears sunken in during rise with later peak, narrower pointed tip
• >>shorter ejection period: longer R-wave to onset of flow
• loss of dicrotic notch

• LVH ( >QRS amplitude: voltage criteria; i.e., tall R-waves in LV leads, deep S-waves in RV leads)
• LAE (wide p-wave)

• Increased risk of syncope and low SBP (narrow pulse pressure)
• Lethal arrhythmias
• Endocarditis
• Systemic embolus

• Calcified/senile valvular stenosis tends to present at ages 70-85
• Bicuspid valve congenital AS typically presents at age 45-65

• Calcified valve appears very echogenic and filled in
• Normal M-Mode AV cusp flutter not seen in AS
• Reduced ACS <1.5cm, <.8cm severe (degree of stenosis determined by CW/PW Doppler)

• short axis shows only 2 leaflets open in systole
• long axis bowing of leaflets into aorta gives domelike appearance (doming in diastole as well)
• M-mode may show eccentric closure line
• typically anterior or rightward leaflet is larger with a raphe which makes it look tricuspid in diastole

• Congenital unicuspid valves causing AS may be seen in childhood, young adulthood
• may be due to restenosis after valvulotomy
• seen as single eccentric orifice (teardrop) with prominent systolic doming

• 9% AS due to Rheumatic - strep bacteria attacks connective tissue, Rheumatic Heart Disease
• occurs concurrently with mitral rheumatic disease
• presents in young adults
• results in commissural fusion of the aortic leaflets
• 2D shows increased echogenicity along leaflet edges, commissural fusion and systolic doming

turbulent (aliased) jet seen past aortic valve due to increased velocities and post-stenotic turbulence

• PPG (Bernoulli equation)
• MPG (Doppler trace)
• AVA (continuity equation)
• Aortic valve index
• V1/V2 ratio

Bernoulli Equation:

PPG = 4 (V2² - V1²)

If V1<1 m/sec use simplified Bernoulli: PPG = 4 (V2²)

• <36 mmHg = mild AS
• 36-64 mmHg = moderate
• >64 mmHg = Severe AS

• <20 mmHg = mild AS
• 20-40 mmHg = moderate
• >40 mmHg = severe

• Dependent on volume flow rate
• elevated or reduced SV can lead to erroneous conclusions regarding severity of AS
• (SV increase due to anxiety, exercise, AI, etc; decrease due to sedation, CHF, hypovolemia, MR)

significant AI >> incr. SV >> incr. velocity >> incr. PPG/MPG >> AS looks worse than it really is

Continuity equation: AVA cm² = .785 * LVOTd² * VTI _lvot / VTI _av


Simplified Continuity equation substitutes max velocities for VTIs:

AVA cm² = .785 * LVOTd² * V1/V2

* LVOT diameter needs to measured 3 times

• Normal = 2.5 - 4.5 cm²
• Mild AS = > 1.5 cm²
• Moderate = 1.0 - 1.5 cm²
• Severe = < 1 cm²

• It can overestimate the severity of AS in patients with significant LV dysfunction.
• (Low dose dobutamine can be given to increase SV and AVA in suspect cases)

Subaortic stenosis may be mistaken for AS

LVOTd can be difficult to measure errors are squared - some physicians encourage LVOTd close to 2cm

AV Index = AVAcm² / BSAm

• Norms:
• Mild = >.85
• Moderate = .6 - .85
• Severe = < .6

Normal V1/V2 = 1

Ratio of .5 indicates valve area is half normal, .25 = 1/4, etc

Generally, V1/V2 < .25 is considered severe (AVA <.75cm²)

• Mild: > .5
• Moderate: .25 - .5
• Severe: <.25

Advantages: takes LVOT diameter out of equation, allows easy tracking of patient over time

small, non imaging probe can obtain the highest velocities or VTI through the AV

used at the apex, RSB and SSN