Aortic stenosis resident survival guide

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Alejandro Lemor, M.D. [2]

Aortic Stenosis Resident Survival Guide Microchapters
Overview
Causes
FIRE
Diagnosis
Treatment
General Approach
Choice of Intervention
Type of Valve and Discharge Anticoagulation Therapy
Do's
Don'ts

Overview

Aortic stenosis is the progressive narrowing of the diameter of the aortic valve (normal valve area is 3 - 4 cm²). Symptoms of aortic stenosis are evident when the stenosis is ≤ 1.0 cm². The symptoms are caused by a decrease in the stroke volume which leads to the subsequent decrease in perfusion to peripheral tissues. The most common etiology of arotic stenosis is calcific aortic valve disease. The management of aortic stenosis depends on whether the patient is symptomatic or asymptomatic. Aortic valve replacement is the treatment of choice for symptomatic patients.

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

Common Causes

Click here for the complete list of causes.

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients in need of immediate intervention.[1]
Abbreviations: AVR: aortic valve replacement; CK-MB: Creatine kinase myocardial type; ECG: electrocardiogram; NSTEMI: non ST elevation myocardial infarction; STEMI: ST elevation myocardial infarction; TTE: transthoracic echocardiography
Boxes in the salmon color signify that an urgent management is needed.

 
 
 
 
 
 
Identify cardinal findings that increase the pretest probability of aortic stenosis

Systolic ejection murmur
❑ Crescendo-decrescendo
❑ Associated with an ejection click
❑ Best heard at the upper right sternal border
❑ Bilateral radiation to the carotid arteries
❑ Increases with squatting and expiration
❑ Decreases with valsalva maneuver

Pulsus parvus et tardus

Narrow pulse pressure
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Does the patient have any of the following findings of decompensated aortic stenosis that require urgent management?
Tachycardia
Hypotension
Severe dyspnea
Loss of consciousness
Chest pain
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Yes
 
 
 
No
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
What is the complication of aortic stenosis that is causing decompensation?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

❑ Suspect in case of:
❑ Severe dyspnea
❑ Signs of volume overload
 

❑ Suspect in case of palpitations
❑ Order an ECG immediately looking for
❑ Irregularly irregular rhythm, and
❑ Absent P waves
 

❑ Suspect in case of loss of consciousness of:
❑ Short duration
❑ Rapid onset
❑ Complete spontaneous recovery
 

❑ Suspect in case of severe chest pain
❑ Order an ECG immediately

❑ Order troponin and CK-MB

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Treat the complications of aortic stenosis that lead to decompensation
❑ Order a TTE to evaluate the severity of the aortic stenosis
❑ Do not give nitrates (could cause severe hypotension)
❑ Monitor vital signs continuously
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Does the patient improve with medical therapy?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No
 
Yes
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Proceed with urgent AVR
 
 



Complete Diagnostic Approach

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.[1]

Abbreviations: AF: atrial fibrillation; AVR: aortic valve replacement; CXR: chest X-ray; ECG: electrocardiogram; LBBB: left bundle branch block; LVH: left ventricle hypertrophy; TAVR: transcatheter aortic valve replacement; TTE: transthoracic echocardiography; VHD: valvular heart disease

 
 
 
 
Characterize the symptoms:
❑ Asymptomatic
Dyspnea on exertion
Dizziness on exertion
Syncope
Chest pain
Palpitations
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Inquire about past medical history:
Cardiovascular disease
Hypertension
Bicuspid aortic valve
Rheumatic fever
Pulmonary disease
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Examine the patient:

Vitals
Heart rate

❑ Normal rhythm and rate (in most cases)
❑ Irregularly irregular rhythm (suggestive of AF in late stage disease)

Blood pressure

Narrow pulse pressure (<25 mmHg)
❑ Mild hypertension in moderate stenosis
Hypotension in severe stenosis

❑ Respiratory rate

❑ Normal in most cases
Tachypnea (suggestive of HF)


Cardiovascular examination
Cardiac palpation

Apical impulse (suggestive of LVH)
Palpable thrill

❑ Pulses

Pulsus parvus et tardus
Pulsus bisferiens (suggestive of mixed aortic stenosis and regurgitation)

Cardiac auscultation

Murmur
❑ Crescendo-decrescendo systolic ejection murmur with ejection click
❑ Best heard at the upper right sternal border
❑ Bilateral radiation to the carotid arteries
❑ Murmur increases with squatting and expiration
❑ Murmur decreases with valsalva maneuver

Click on the video below to listen to an aortic stenosis murmur. {{#ev:youtube|MJg257pyt4I|200}}

Heart sounds
❑ Normal S1
Paradoxical splitting of S2 (in severe disease)
S3 (suggestive of LVH)


Respiratory examination
Rales (suggestive of congestive heart failure)


Extremities
Peripheral edema (suggestive of congestive heart failure)

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Order tests:

TTE (most important evaluation test) (Class I; Level of Evidence: B)

Assess the following:
❑ Valve morphology
❑ Pressure gradient
Aortic valve area
Ejection fraction
Left ventricle wall thickness and motility

ECG (shows non-specific findings):

LVH
Left atrium enlargement
LBBB
AF (in late disease)

Chest X-ray:

Cardiomegaly
Valve calcification
❑ Dilatation of ascending aorta
Pulmonary congestion
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Classify aortic stenosis based on the following findings on TTE:
❑ Valve area
❑ Transvalvular pressure gradient
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No stenosis

❑ Valve area 2.5-3.5 cm²
❑ No pressure gradient across the valve
 
Mild stenosis

❑ Valve area 1.5-2.5 cm²
❑ Pressure gradient ≤ 25 mmHg
 
Moderate stenosis

❑ Valve area 1.0-1.5 cm²
❑ Pressure gradient 25-40 mmHg
 
Severe stenosis

❑ Valve area ≤ 1.0 cm²
❑ Pressure gradient ≥ 40 mmHg
 
 
 
 

Treatment

General Approach

Shown below is an algorithm for the treatment of aortic stenosis according to the stage of the disease based on the 2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease [1]

 
 
 
 
Classify aortic stenosis based on the following findings on TTE:
❑ Valve area
❑ Transvalvular pressure gradient
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No stenosis (Stage A)

❑ Valve area 2.5-3.5 cm²
❑ No pressure gradient
 
Mild to moderate stenosis (Stage B)
Mild
❑ Valve area 1.5-2.5 cm²
❑ Pressure gradient ≤ 25 mmHg
Moderate
❑ Valve area 1.0-1.5 cm²
❑ Pressure gradient 25-40 mmHg
 
 
 
 
 
Severe stenosis

❑ Valve area ≤ 1.0 cm²
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Asymptomatic patients
❑ Normal valve
Bicuspid valve
Sclerotic valve
 
Asymptomatic patients
Control hypertension (Class I; Level of Evidence: B)
Perform a periodic echocardiogram (Class I; Level of Evidence:B)
❑ Every 3 -5 years for mild stenosis
❑ Every 1 - 2 years for moderate stenosis
 
 
 
Asymptomatic
(Stage C)

❑ Pressure gradient ≥ 40 mmHg
 
 
 
 
Symptomatic
(Stage D)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
If patient undergoes another cardiac surgery:
Schedule for AVR (Class IIa; Level of Evidence: C)
 
Normal LVEF
(Stage C1)
 
LVEF < 50%
(Stage C2)
 
High gradient (ΔP ≥ 40 mmHg)
(Stage D1)
 
Low gradient (ΔP ≤ 40 mmHg)
❑ LVEF < 50% (Stage D2)
❑ Normal LVEF (Stage D3)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Perform a periodic echocardiogram every 6 - 12 months (Class I; Level of Evidence: B)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
If aortic velocity ≥ 5 m/s or there is a decrease in exercise tolerance:
Schedule for AVR (Class IIa; Level of Evidence: B)
 
 
 
 
 
 
 
 
 
 
 
 
 

Choice of Intervention

Shown below is an algorithm summarizing the choice of aortic valve replacement among patients with aortic stenosis based on the 2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease [1]

 
 
 
 
 
 
Assess the surgical and interventional risk of the patient
(The risk score is shown below)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
High risk
 
 
 
 
 
Low to moderate risk
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ A multidisciplinary group should decide intervention (surgical AVR or TAVR) (Class I; Level of Evidence: C)
❑ Consider TAVR (Class IIa; Level of Evidence: B)[1] [2]
 
 
 
 
 
❑ Schedule for surgical AVR (Class I; Level of Evidence: A)
 
 
 
 

Evaluation of Surgical and Interventional Cardiac Risk

Shown below is a table to assess the surgical and interventional risk which combines the STS risk estimate, frailty, major organ system dysfunction and procedure-specific impediments.[1]

Society of Thoracic Surgeons Predicted Risk of Mortality Score [3]
Frailty* Major organ system compromised without postoperative improvement Specific procedural impediment **
Low risk <4%
AND
None
AND
None
AND
None
Intermediate risk 4% to 8%
OR
1 index
OR
1 organ system
OR
Possible
High risk >8%
OR
≥2 indices (moderate to severe)
OR
No more than 2 organ systems
OR
Possible
Prohibitive risk >50% of predicted risk of death or major morbidity at 1 year
OR
>50% of predicted risk of death or major morbidity at 1 year
OR
≥3 organ systems Severe

*Seven frailty indices: Katz Activites of Daily Living (self-sufficient in feeding, bathing, dressing, transferring, toileting and urinary continence) and self-sufficient in deambulation (no walking aid or assist required or 5-meter walk in <6 s).
**Examples of specific procedural impediment: tracheostomy present, heavily calcified ascending aorta, chest malformation, arterial coronary graft adherent to posterior chest wall or radiation damage.

Type of Valve and Discharge Anticoagulation Therapy

 
 
 
 
 
 
Determine:
Age
Contraindications for anticoagulation
❑ Major bleeding diathesis or coagulopathy
❑ Uncontrolled severe hypertension (systolic BP >200 mmHg)
❑ Recent head trauma
❑ Platelet count < 100 000
Pregnancy
❑ Hypersensitivity to warfarin
Hemorrhagic stroke
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Patients ≤ 60 years old (Class IIa; Level of Evidence: B), AND
❑ No contraindication for anticoagulation
 
❑ Patients 60 - 70 years old
❑ No contraindication for anticoagulation
 
❑ Patients ≥ 70 years old (Class IIa; Level of Evidence: B), OR
❑ Patients with contraindications for anticoagulation therapy (Class I; Level of Evidence: C)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Mechanical Prosthesis
Avoid the use of direct thrombin inhibitors or anti-Xa agents in patients with mechanical prosthesis (Class III; Level of Evidence: B)
 
Either a bioprosthesic or mechanical valve is reasonable (Class IIa; Level of Evidence: B).
 
Bioprosthesis
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Patient with risk factors†
 
Patient without risk factors†
 
Surgical AVR
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Administer for long term:
Warfarin to achieve INR of 3.0
Aspirin 75-100 mg/d
 
Administer for long term:
Warfarin to achieve INR of 2.5
Aspirin 75-100 mg/d
 
❑ Administer warfarin to achieve INR of 2.5 for 3 months
❑ Then administer aspirin 75-100 mg/d long term
 
Administer for 6 months:
Clopidogrel 75 mg/d
Aspirin 75-100 mg/d
 


†Risk factors for thromboembolism include atrial fibrillation, hypercoagulable conditions, LV dysfunction, and previous thromboembolism.

Do's

Don'ts

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 Nishimura, R. A.; Otto, C. M.; Bonow, R. O.; Carabello, B. A.; Erwin, J. P.; Guyton, R. A.; O'Gara, P. T.; Ruiz, C. E.; Skubas, N. J.; Sorajja, P.; Sundt, T. M.; Thomas, J. D. (2014). "2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines". Circulation. doi:10.1161/CIR.0000000000000031. ISSN 0009-7322.
  2. Smith, Craig R.; Leon, Martin B.; Mack, Michael J.; Miller, D. Craig; Moses, Jeffrey W.; Svensson, Lars G.; Tuzcu, E. Murat; Webb, John G.; Fontana, Gregory P.; Makkar, Raj R.; Williams, Mathew; Dewey, Todd; Kapadia, Samir; Babaliaros, Vasilis; Thourani, Vinod H.; Corso, Paul; Pichard, Augusto D.; Bavaria, Joseph E.; Herrmann, Howard C.; Akin, Jodi J.; Anderson, William N.; Wang, Duolao; Pocock, Stuart J. (2011). "Transcatheter versus Surgical Aortic-Valve Replacement in High-Risk Patients". New England Journal of Medicine. 364 (23): 2187–2198. doi:10.1056/NEJMoa1103510. ISSN 0028-4793.
  3. "Online STS Risk Calculator". Retrieved 7 March 2014.
  4. Chambers, J. (2005). "The left ventricle in aortic stenosis: evidence for the use of ACE inhibitors". Heart. 92 (3): 420–423. doi:10.1136/hrt.2005.074112. ISSN 1355-6037.
  5. Bonow, RO.; Carabello, BA.; Chatterjee, K.; de Leon, AC.; Faxon, DP.; Freed, MD.; Gaasch, WH.; Lytle, BW.; Nishimura, RA. (2008). "2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons". Circulation. 118 (15): e523–661. doi:10.1161/CIRCULATIONAHA.108.190748. PMID 18820172. Unknown parameter |month= ignored (help)


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