Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2. Cardiac > Aortic Valve > Flashcards

Aortic Valve Flashcards

0
Q

What is the relative use of mechanical vs tissue valves?

A

15%, USA 2011

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Name 5 points in evaluating a valve procedure’s effectiveness

A
  1. Ease of performance
  2. Safety
  3. Efficacy (haemodynamics, EOA)
  4. Durability
  5. Event-free survival
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Should patients having other cardiac surgery and moderate AS undergo AS?

A

Yes, class IIa indication, level of evidence B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Give 4 indicators of prosthetic aortic valve dysfunction

A
  1. Valve area 20mmHg
  2. Peak velocity >3m/s
  3. Moderate or severe AR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Give 3 class I indications for AVR in aortic stenosis

A
  1. Severe AS and symptoms
  2. Severe AS and LVEF <50%
  3. Severe AS undergoing other cardiac surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What class of indication is AVR for an asymptomatic patient with exercise induced symptoms or abnormal blood pressure response (hypotension)

A

Class IIb, level of evidence C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Is severe asymptomatic AS with high likelihood of progression (age, calcification, CAD) a class I indication for AVR?

A

No. Class IIb, level of evidence C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define severe aortic stenosis (with normal LV)

A
  1. Peak Doppler echo >4m/s
  2. Mean gradient >4mmHg
  3. Valve area <1.0cm2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Is AVR indicated for asymptomatic very severe AS (area 5 m/s, mean >60mmHg)?

A

Only a class IIb, level C indication if operative mortality <1.0%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give 3 class I indications for AVR in aortic regurgitation

A
  1. Symptomatic severe AR
  2. Asymptomatic severe AR and LVEF <50%
  3. Severe AR undergoing other cardiac surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When is AVR indicated in severe asymptomatic AR and normal LV systolic function?

A 
LVESD >50mm
LVEDD >70mm
Or progressive LV dilatation
Or declining exercise tolerance
Or abnormal haemodynamic response to exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define severe aortic regurgitation

A 
Evidence of volume load on LV &:
Regurgitant orifice area >0.3cm2
Regurgitant fraction>60%
Regurgitant volume >60ml/beat
Vena contracta width >0.6cm (point in a fluid stream where the diameter is the least)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Give 3 indications for surgery in aortic valve endocarditis

A
  1. Severe heart failure
  2. Abscesses, heart block, resistant infection
  3. Recurrent emboli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give 5 measurements indicating a need for replacement of the ascending aorta or root when aortic valve is bicuspid

A
  1. Diameter > 5.0cm (5.5 if tricuspid)
  2. Diameter > 2.5cm/m2
  3. Cross-section : Ht ratio >10cm2/m
  4. Dilating >0.5cm/yr
  5. > 4.5cm if undergoing AVR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give the 4 main factors to consider in the preoperative assessment of AS

A
  1. Verify disease severity
  2. Evaluate LV function
  3. Assess for coronary disease
  4. Delineate major comorbidities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the expected survival for untreated severe symptomatic AS?

A

Mean survival 2 years (1yr 50%, 5 yr 20%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Give a definition of frailty

A

3 or more of following present:

  • unintentional weight loss >10lb/yr
  • self-reported exhaustion
  • weakness (grip strength)
  • slow walk speed (<5m/6sec)
  • low physical activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give 3 physical signs of AR

A
  • decrescendo diastolic murmur left sternal border
  • wide pulse pressure
  • bounding pulses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Give 3 physical findings in AS

A
  • ejection systolic murmur, radiation to carotids
  • single or paradoxically split 2nd sound
  • diminished carotid upstroke
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What features might be seen on a CXR in AS?

A
  • rounded heart border due to LVH
  • aortic calcification
  • pulmonary oedema + cephalic blood flow in left heart failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What PFT values predict increased postoperative morbidity after AVR?

A
  • pCO2 >50mmHg

* FEV1 <50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How might chronic pulmonary disease be distinguished from AS as a cause of dyspnoea?

A

Balloon aortic valvuloplasty (BAV) as a physiological test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the Gallavardin phenomenon in AS?

A

The musical component of an AS murmur best heard at the apex

23
Q

What ECG changes occur with AS?

A
  • Evidence of LVH

* Conduction abnormalities (LBBB or RBBB with R/L axis deviation)

24
Q

Give 6 class I indications for rchocardiography in AS or AR

A
  • check severity
  • assess LV size, function, wall thickness
  • changing signs & symptoms
  • monitor asymptomatic patients
  • monitor change in pregnancy
  • check intra-operative repair / replacement
25
Q

How often should asymptomatic AS or AR patients have echo assessment?

A
  • severe 6 months
  • moderate 1-2 years
  • mild 3-5 years
26
Q

What is the role of exercise testing in AS or AR?

A

May be considered if asymptomatic to induce symptoms or abnormal blood pressure response [<20mmHg rise] (class IIb). It should not be performed if symptomatic (high risk complications)

27
Q

How can true gradients be determined in AS with LV dysfunction?

A

This is low-flow low-gradient AS → low-dose dobutamine infusion

28
Q

What ECG changes occur with exercise testing in AS?

A

80% develop ST-depression, of no known prognostic value

29
Q

What are the uses of CT in assessment for TAVI?

A
  • potential leaflet calcium obstructing coronary ostia
  • aortic annulus diameter
  • assess aortoiliac system (size, disease,(tortuosity)
30
Q

What is a positive test in dobutamine stress echo?

A

Fixed valve area with an increase in gradient and stroke volume
Failure to increase stroke volume => lack of contractile reserve → very poor prognosis (with medicine or surgery)

31
Q

Give 4 class I indications for cardiac catheterisation in assessment of AS or AR

A
  • look for coronary disease if risk factors
  • look for coronary disease if >45 years
  • haemodynamic measurements if inconclusive non-invasive tests
  • Ross procedure planned
32
Q

What measurements are made, if indicated, to assess AS at cardiac catheterisation?

A
  • simultaneous LV and ascending aortic pressures

* cardiac output by Fick principle or indicator-dilution

33
Q

How often is the Circle of Willis incomplete?

A

15%

34
Q

What are the cannulation options for AVR and aortic root surgery?

A
  • ascending aorta
  • aortic arch
  • axillary /subclavian (with 8mm dacron graft)
  • femoral artery (right is spared in 80% of dissections)
  • LV apex
35
Q

What are the disadvantages of femoral artery cannulation?

A
  • size (achieving adequate body perfusion)
  • distal limb perfusion compromise
  • atherosclerotic disease involvement (emboli)
36
Q

Give 4 class I management recommendations for patients receiving mechanical AVR

A
  • preoperative coronary angiogram for CAD symptoms, risk or age >45
  • perioperative antibiotic prophylaxis
  • warfarin for life
  • dental antibiotic cover
37
Q

What orientation gives the least turbulence in mechanical bileaflet AVR?

A

Axis of leaflets in middle of non-coronary cusp

38
Q

Give 5 potential late complications of mechanical AVR

A
  • thromboembolism & bleeding (warfarin)
  • structural dysfunction
  • non-structural dysfunction (paravalvular leak, haemolysis)
  • tissue ingrowth
  • endocarditis
39
Q

What are the approximate rates of mechanical AVR complications?

A
  • structural dysfunction 0.1% / yr
  • non-structural dysfunction 0.2% / yr
  • thromboembolism 1-2% / yr
  • bleeding 1-2% / yr
  • endocarditis 0.5% / yr
40
Q

Give 4 indications for tissue over mechanical AVR

A
  • Contraindication to anticoagulation (class I)
  • age >65 (class I)
  • patient preference (class IIa)
  • woman of childbearing age (class IIb)
41
Q

What are the 3 types of tissue prosthesis?

A
  • xenograft (stented, stentless) - porcine, pericardial
  • homograft (=allograft)
  • autograft (Ross procedure)
42
Q

How does the internal diameter of a bioprosthesis relate to it’s labelled valve sizer?

A

standard valve 4-6mmHg smaller

suprannular valve 2-4mmHg smaller

43
Q

What are the pros and cons of collagen cross-linking with gluteraldehyde of bioprostheses?

A 
Pros:
* block immune response
* tissue stabilisation
Cons:
* creates calcium influx
* exposes residual phospholipids (→ Ca++ binding)
44
Q

What factors increase to rate of structural valve deterioration of bioprostheses?

A 
Age
Female
Larger valve
Mitral position
Renal failure
Hyperparathyroidism
Hypertension
45
Q

What are the structural valve deterioration incidence by 15 years for a bioprosthesis inserted at age: >65, <40?

A

> 65 → 10%

<40 → 40%

46
Q

How does structural valve deterioration differ between porcine and pericardial valves?

A

Porcine valve calcification at areas of high stress (commissures) leading to acute tears
Pericardial calcification diffuse, leading to gradual AS

47
Q

In aortic valve replacement, what is the effective orifice area (EOA) index?

A

EOA/BSA, used to identify patient prosthesis mismatch (ppm)

48
Q

What is patient-prosthesis mismatch and how is it defined?

A

Present when the effective prosthetic heart valve area, after insertion into the patient, is less than that of a normal human valve. Use same criteria as for native valve stenosis (e.g. severe if <0.6cm2/m2

49
Q

When should patch enlargement of aortic root be considered in AVR?

A

When EOA of prosthesis will be <0.65cm2/m2

50
Q

Give 5 methods to increase inserted prosthesis size in the small aortic root

A
  1. Konno - through R sinus into muscular septum
  2. Manouguian - through NC/LC commissure, may involve LA dome
  3. Nicks - through mid NC sinus, maybe onto anterior MV leaflet
  4. Supra-annular insertion
  5. Root replacement
51
Q

Give 2 class I recommendations in homograft replacement of the aortic valve

A
  1. Consider in endocarditis with extensive destruction of annulus
  2. Use as a root replacement preferred
52
Q

Describe 3 types of homograft AVR

A
  1. Sub-coronary implantation
  2. Root inclusion cylinder
  3. Total root replacement
53
Q

Give 3 pros & 3 cons of stentless aortic valve replacement

A 
Pros:
1. Excellent haemodynamics
2. Avoid anticoagulation
3. Readily available
Cons:
1. More demanding insertion
2. Uncertain durability
3. TAVI replacement difficult
54
Q

Give 3 potential indications for stentless aortic root replacement

A
  1. Small root with high risk patient-prosthesis mismatch
  2. Aneurysmal root
  3. Endocarditis with annular destruction
55
Q

What is the main indication for AVR using the Ross procedure?

A

Children with no suitable alternative

56
Q

What are the long-term disadvantages of the Ross procedure?

A
  • neo-aortic dilatation
  • neo-aortic valve regurgitation
  • pulmonary homograft failure

2. Cardiac (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions