Aortic stenosis: Difference between revisions

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==Background==
==Background==
*Younger patients: usually from a congenital bicuspid valve
*Older patients: usually from calcifications on aortic valve
*Rheumatic heart disease is the next most common
*Significant obstruction when orifice <1 cm or pressure grad is >50 mmHg


==Clinical Features==
==Clinical Features==
*Dyspnea, CP, syncope
*[[Dyspnea]], [[chest pain]], [[syncope]]
**Once symptoms present mean surival is 2-3yr
**Once symptoms present mean survival is 2-3yr
*ejection systolic murmur radiating to carotids
**Natural history is [[angina]], then [[syncope]], then dyspnea from [[CHF]] which is late stage
*Pulsus parvus et tardus, slow to rise and late peaking
*Ejection systolic [[murmur]] radiating to carotids
*''Pulsus parvus et tardus'' - slow to rise and late peaking
*Narrowed pulse pressure
*Narrowed pulse pressure
*Soft 2nd heart sound
*Soft 2nd heart sound
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{{Valvular emergencies DDX}}
{{Valvular emergencies DDX}}


==Diagnosis==
==Evaluation==
*Echocardiography, transthoracic
*[[Echocardiography]], TTE findings
**This will typically demonstrate minimal excursion of the aortic valve leaflet
**Minimal excursion of the aortic valve leaflet
**Continuous wave doppler across the aortic valve with typically demonstrate high velocities
**Calcifications of AV
**Color doppler will demonstrate turbulent flow across the valve
**Systolic "doming" on parasternal long
**The left ventricle will demonstrate left ventricular hypertrophy
**Turbulent flow through AV on color doppler
*Severity by CW Doppler velocity (m/s)<ref>Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP, Iung B, Otto CM, Pellikka PA, Quiñones M, American Society of Echocardiography, and European Association of Echocardiography. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr. 2009 Jan;22(1):1-23; quiz 101-2.</ref>
**LV hypertrophy
**Number of leaflets (unicuspid, bicuspid, tricuspid, quadricuspid)<ref>Baumgartner H et al. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. European Journal of Echocardiography (2009) 10, 1–25.</ref>
***Raphe in bicuspid aortic valve in diastole may false negatively appear like trileaflet valve
***Only comment on the number of leaflets in '''systole''' in parasternal short axis
*Severity by continuous wave (CW) Doppler peak velocity (m/s)<ref>Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP, Iung B, Otto CM, Pellikka PA, Quiñones M, American Society of Echocardiography, and European Association of Echocardiography. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr. 2009 Jan;22(1):1-23; quiz 101-2.</ref>
**'''AS is unlikely if peak CW velocity well below 2.5 m/s, and AVA measurements may not be necessary'''
**Ensure parallel intercept angle across aortic valve in apical view
**Ensure parallel intercept angle across aortic valve in apical view
**<2.5 = aortic sclerosis
**< 2.5 = aortic sclerosis
**2.6 - 2.9 = mild
**2.6 - 2.9 = mild
**3.0 - 4.0 = moderate
**3.0 - 4.0 = moderate
**>4.0 = severe
**> 4.0 = severe
*Aortic valve area (AVA) requires LVOT diameter (D) and velocity time integral (VTI) at LVOT and AV in the continuity equation
**More reliable than CW doppler peak velocity
**Obtain LVOT diameter just apical to AV in PSL at maximal systole
**Obtain the following in apical view at the aortic valve '''as parallel to flow as possible''' to avoid falsely low values
***AV VTI (continuous wave doppler), gate at tips of AV opening in systole, tracing below the line in systole
***LVOT VTI (pulse wave doppler), gate in LVOT just apical to AV, tracing below the line in systole
**Aortic stenosis valve area severity<ref>Saito T et al. Prognostic value of aortic valve area index in asymptomatic patients with severe aortic stenosis. Am J Cardiol. 2012 Jul 1;110(1):93-7.</ref>
***Normal, > 2.5 cm²
***Mild, 2.5 - 1.5 cm²
***Moderate, 1.0 - 1.5 cm²
***Severe, < 1.0 cm²
[[File:AVA continuity equation.PNG|thumbnail|AVA Continuity Equation]]
[[File:AS Measurement Table.png|thumbnail|AS Measurements and Grading]]
[[File:Lvot diameter.jpg|thumbnail|LVOT Diameter (D) in cm]]
[[File:LVOT VTI.png|thumbnail|LVOT VTI in cm]]
[[File:AV VTI.png|thumbnail|AV VTI in cm]]
[[File:AS doming.jpg|thumbnail|Systolic "doming"]]
*Caveats in TTE for AS
**Eccentric mitral regurgitation jets may interfere with AV flows
**Atrial fibrillation poses different levels of diastolic and systolic filling, requiring multiple tracings
**Poor LV function may reduce velocities upon measuring, while AS may still be present


==Treatment==
==Management==
*Avoid negative inotropes such as BBs, CCBs
*''Avoid'' negative inotropes such as beta-blockers, calcium-channel blockers
*Afterload reduction is controversial and in decompensated AS should only be conducted in a monitored setting
*Afterload reduction is controversial and in decompensated AS should only be conducted in a monitored setting
**Consider cards consult  
**Consider cardiology consult  
*AS + A-fib = emergency
*AS + [[A-fib]] = emergency
**Consider emergent cardioversion
**Consider emergent [[cardioversion]]
*Pulm edema
*[[Pulmonary edema]]
**Diuretics, NIV, and intubation if necessary
**[[Diuretics]], [[NIPPV|NIV]], and [[intubation]] if necessary
**Extreme caution with use of nitrates/vasodilators
***[[Etomidate]] is the induction agent of choice
*In critical cases, particularly in those unstable to undergo emergent surgery, balloon aortic valvuloplasty may be an option as bridge to AVR
**Extreme caution with use of nitrates/vasodilators (preload reducers)
**Blood transfusions may cause flash pulmonary edema
**[[IVF|Fluid administration]] takes precedence over worsening pulmonary edema in order to increase preload in patients who are hypotensive
*[[Vasopressors]]
**[[Phenylephrine]] is the vasopressor of choice<ref>Goertz AW, Lindner KH, Schutz W, Schirmer U, Beyer M, Georgieff M. Influence of phenylephrine bolus administration on left ventricular filling dynamics in patients with coronary artery disease and patients with valvular aortic stenosis.  Anesthesiology. 1994;81(1):49-58.</ref>
***Increase in afterload  and diastolic blood pressure increases perfusion of coronary arteries
***Reflex bradycardia may also be beneficial
**[[Norepinephrine]] is a reasonable choice
**Avoid [[epinephrine]] as beta-1 agonism may increase tachycardia and myocardial perfusion demand
*In critical cases, particularly in those unstable to undergo emergent surgery, balloon aortic valvuloplasty may be an option as bridge to AVR or palliative care in nonsurgical candidates


==Disposition==
==Disposition==
*Severe HF symptoms resistant to medical management require urgent surgery
*Severe [[heart failure]] symptoms resistant to medical management require urgent surgery
*Class I indications for AVR:
*Class I indications for AVR:
**Severe AS in symptomatic pt
**Severe AS in symptomatic pt
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*[[Heart murmurs]]
*[[Heart murmurs]]
*[[Cardiogenic shock]]
*[[Cardiogenic shock]]
*See [https://www.youtube.com/watch?v=HztsPbymUhA Intro to Aortic Stenosis by Joseph Minardi on YouTube]
==External Links==
*[https://www.emra.org/emresident/article/the-crashing-patient-with-critical-aortic-stenosis/ EMRA: The Crashing Patient with Critical Aortic Stenosis]
*[http://www.emdocs.net/pocus-for-aortic-stenosis/ emDocs - Pocus for Aortic Stenosis]


==References==
==References==
<references/>
<references/>
[[Category:Cards]]
 
[[Category:Cardiology]]

Latest revision as of 22:24, 16 September 2021

Background

  • Younger patients: usually from a congenital bicuspid valve
  • Older patients: usually from calcifications on aortic valve
  • Rheumatic heart disease is the next most common
  • Significant obstruction when orifice <1 cm or pressure grad is >50 mmHg

Clinical Features

  • Dyspnea, chest pain, syncope
    • Once symptoms present mean survival is 2-3yr
    • Natural history is angina, then syncope, then dyspnea from CHF which is late stage
  • Ejection systolic murmur radiating to carotids
  • Pulsus parvus et tardus - slow to rise and late peaking
  • Narrowed pulse pressure
  • Soft 2nd heart sound

Differential Diagnosis

Valvular Emergencies

Evaluation

  • Echocardiography, TTE findings
    • Minimal excursion of the aortic valve leaflet
    • Calcifications of AV
    • Systolic "doming" on parasternal long
    • Turbulent flow through AV on color doppler
    • LV hypertrophy
    • Number of leaflets (unicuspid, bicuspid, tricuspid, quadricuspid)[1]
      • Raphe in bicuspid aortic valve in diastole may false negatively appear like trileaflet valve
      • Only comment on the number of leaflets in systole in parasternal short axis
  • Severity by continuous wave (CW) Doppler peak velocity (m/s)[2]
    • AS is unlikely if peak CW velocity well below 2.5 m/s, and AVA measurements may not be necessary
    • Ensure parallel intercept angle across aortic valve in apical view
    • < 2.5 = aortic sclerosis
    • 2.6 - 2.9 = mild
    • 3.0 - 4.0 = moderate
    • > 4.0 = severe
  • Aortic valve area (AVA) requires LVOT diameter (D) and velocity time integral (VTI) at LVOT and AV in the continuity equation
    • More reliable than CW doppler peak velocity
    • Obtain LVOT diameter just apical to AV in PSL at maximal systole
    • Obtain the following in apical view at the aortic valve as parallel to flow as possible to avoid falsely low values
      • AV VTI (continuous wave doppler), gate at tips of AV opening in systole, tracing below the line in systole
      • LVOT VTI (pulse wave doppler), gate in LVOT just apical to AV, tracing below the line in systole
    • Aortic stenosis valve area severity[3]
      • Normal, > 2.5 cm²
      • Mild, 2.5 - 1.5 cm²
      • Moderate, 1.0 - 1.5 cm²
      • Severe, < 1.0 cm²
AVA Continuity Equation
AS Measurements and Grading
LVOT Diameter (D) in cm
LVOT VTI in cm
AV VTI in cm
Systolic "doming"
  • Caveats in TTE for AS
    • Eccentric mitral regurgitation jets may interfere with AV flows
    • Atrial fibrillation poses different levels of diastolic and systolic filling, requiring multiple tracings
    • Poor LV function may reduce velocities upon measuring, while AS may still be present

Management

  • Avoid negative inotropes such as beta-blockers, calcium-channel blockers
  • Afterload reduction is controversial and in decompensated AS should only be conducted in a monitored setting
    • Consider cardiology consult
  • AS + A-fib = emergency
  • Pulmonary edema
    • Diuretics, NIV, and intubation if necessary
    • Extreme caution with use of nitrates/vasodilators (preload reducers)
    • Blood transfusions may cause flash pulmonary edema
    • Fluid administration takes precedence over worsening pulmonary edema in order to increase preload in patients who are hypotensive
  • Vasopressors
    • Phenylephrine is the vasopressor of choice[4]
      • Increase in afterload and diastolic blood pressure increases perfusion of coronary arteries
      • Reflex bradycardia may also be beneficial
    • Norepinephrine is a reasonable choice
    • Avoid epinephrine as beta-1 agonism may increase tachycardia and myocardial perfusion demand
  • In critical cases, particularly in those unstable to undergo emergent surgery, balloon aortic valvuloplasty may be an option as bridge to AVR or palliative care in nonsurgical candidates

Disposition

  • Severe heart failure symptoms resistant to medical management require urgent surgery
  • Class I indications for AVR:
    • Severe AS in symptomatic pt
    • Severe AS undergoing CABG, aortic, or valve surgery
    • Severe AS with LV dysfunction, EF < 50%

See Also

External Links

References

  1. Baumgartner H et al. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. European Journal of Echocardiography (2009) 10, 1–25.
  2. Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP, Iung B, Otto CM, Pellikka PA, Quiñones M, American Society of Echocardiography, and European Association of Echocardiography. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr. 2009 Jan;22(1):1-23; quiz 101-2.
  3. Saito T et al. Prognostic value of aortic valve area index in asymptomatic patients with severe aortic stenosis. Am J Cardiol. 2012 Jul 1;110(1):93-7.
  4. Goertz AW, Lindner KH, Schutz W, Schirmer U, Beyer M, Georgieff M. Influence of phenylephrine bolus administration on left ventricular filling dynamics in patients with coronary artery disease and patients with valvular aortic stenosis. Anesthesiology. 1994;81(1):49-58.