Ch 10 Aortic Valve, Stenosis, and insufficiency Flashcards
(112 cards)
1
Q
What are the 3 components of the aortic root?
A
- Aortic Valve
- Sinus of Valsalva
- Interleaflet Triangles
2
Q
What are all the names (List 4) of the 3 aortic cusps?
A
Cusps
Leaflets
Scallops
Valvules
3
Q
What is usually the largest aortic valve cusp?
A
Non-Coronary Cusp
4
Q
How are the aortic valve cusp named?
A
Corresponding sinus of Valsalva
5
Q
What % of people have bicuspid aortic cusp?
A
2.5%
6
Q
What is the most common configuration of bicuspid aortic valve?
A
Left and Right Fusion
***
7
Q
What are Lambl’s Excrescences?
A
Degenerative Filamentous straings on the ventricular free margin
8
Q
What is the lunula?
A
The rim of each valve cusp is slightly thicker than the cusp body and is known as the lunula.
9
Q
What is the nodule of Arantius?
A
During diastole, the normal leaflets form a three pointed star with a slight thickening or prominence at the central closing point formed by the aortic leaflet nodules, known as the nodules of Arantius
10
Q
What is the sinus of valsalva?
A
Expanded parts of the ascending aorta enclosed superiorily by the STJ and inferiorly by attachment of the valve cusps
11
Q
What is the role of the sinus of valsalva?
A
- Important role in AV cusp motion
- Distribution of stress in the cusps
- Act as reservoirs during diastole to perfuse the coronaries
12
Q
If the sinotubular junction exceeds free margin cusp length, what will happen?
A
STJ diltation >> Free margin length = Cusp Mal-coaptation and Central AI
13
Q
If you have isolated annular dilation excluding the STJ
1. What does this do to the commissural height?
2. Cause AI?
A
Reduces commissural height
Does not cause AI
14
Q
What two structures make up the free margin of the aortic valve?
A
Lunula + Nodule of Arantius
15
Q
The aortic cusp base is what relative length to the free margin length?
A
The aortic cusp base is 1.5x longer than the free margin length
16
Q
What is the composition of the aortic valve cusp base at the hing-points?
A
55% fibrous
45% muscular
(Green in picture)
17
Q
What aspect of the aortic valve architecture make the valve vulnerable to anuerysm formation?
A
Crown peaks (Interleaflet triangles) - Red in photo
- Composed of thin fibrous sinus of valsalva walls (Not LV myocardium)
18
Q
What are the 3 rings that describe the aortic root?
A
1. Aortic Annulus
- Basal cusp attachments in the LV)
2. Anatomic VA (Ventriculoarterial juntion)
- Ventricular structures changes to fibroelastic aortic wall
3. STJ - Give Structural support
19
Q
The aortic root forms the transformation of what two structures?
A
Muscular LV to the Elastic Aorta
20
Q
What defines the hemodynamic jucntion between the LV and the Aorta?
A
Cusp Attachment
21
Q
What pressures are seen by the cusps proximally and distally?
A
Proximally = Ventricular pressures
Distally = Aortic Pressures
22
Q
From the ME AV SAX view, how would you manipulate the probe to view the coronary ostia?
A
Withdraw the Probe
23
Q
From the ME AV SAX view, how would you manipulate the probe to view the LVOT?
A
Advance the Probe
24
Q
In the ME AV LAX view, the RCC is always anterior or posterior?
A
Anterior
25
For the ME AV LAX, when in the cardiac cycle do you measure the LVOT, AV, STJ and Ascending Aorta?
**Mid-Systole**
26
From what Transgastric view is it best to acquire TG LAX views?
TG Basal Short Axis
27
In the TG views of the Aortic Valve, which cusp signifies the RCC?
It is always located on the left of the screen
28
What are the normal aortic root measurements of:
## Footnote
***_Annulus?_***
20 - 31 mm
29
What are the normal aortic root measurements of:
**Sinuses of Valsalva**?
29 - 45 mm
30
What are the normal aortic root measurements of:
## Footnote
**Sinotubular Junction?**
22 - 36 mm
31
What are the normal aortic root measurements of:
## Footnote
**Ascending Aorta?**
22 - 36 mm
32
**What is the root height?**
What is the typical root height?
**Horizontal Distance between STJ - Annulus**
\< 22 mm
\*\*\* Insert Photo here \*\*\*
33
What are the three levels of aortic stenosis?
1. Subvalvular
2. Valvular
3. Supravalvular
34
What are the 3 most common etiologies of Aortic Stenosis in America?
1. Bicuspid (38%)
2. Degenerative Calcification (33%)
3. Rheumatic (24%)
35
Symptoms of AS are not seen usually until the valve area is what size?
\< 1.0 cm2
36
How much does the incidence of death rise each year with critical aortic stenosis?
10% per year
37
What is the survival rate after AV replacement for AS:
5 years?
10 years?
15 years?
5 = 75%
10 = 61%
15 = 49%
38
For Calcified aortic stenosis, what is usually calcified? (Specifics)
**Aortic annulus** and **mitro-aortic fibrosa** (MAIVF in picture)
Fibrocalcific changes in cusp body
39
What is a bicuspid valve associated with?
Coarctation of Aorta
Dilated Ascending Aorta
Interrupted Aortic Arch
VSD
ASD
PDA
40
What age is calcific aortic stenosis seen?
66 +/- 12 years
41
What age is bicuspid aortic stenosis seen?
48 +/- 6 years
42
What age is rheumatic aortic stenosis seen?
39 +/- 18 years
43
What is the appearance of rheumatic aortic stenosis?
Thick, Calcified Free Edge
Calcific nodules on both surfaces
Commissural fusion
Chordal Shortening
44
In Rheumatic AS, what is also seen almost always?
**Mitral valve pathology** (Isolated AS from Rheumatic is rare)
45
What defines reduced excursion of the valve in aortic stenosis?
\<15 mm in both short and long axis
46
For bicuspid valves, what is seen of the aortic cusp leaflets in systole in the ME AV LAX in terms of their relationship to the aorta?
Curve towards the aorta (**Systolic doming**)
47
What defines aortic sclerosis?
**Aortic valve thickening** but *_no hemodynamic gradient_*
48
What compensatory mechanism occurs within the LV for AS?
LVH (Left Ventricular Hypertrophy)
49
Why does LVH occus in AS?
Compensatory mechanism
- **Flow restriction** and **systolic pressure overload** that minimizes LV Systolic Wall stress (Think LaPlace Law)
50
**What does LVH do to:**
Stroke Volume?
Diastolic Function?
Small SV (Stroke volume)
Diastolic Dysfunction
51
Why is an AS patient at risk for subendocardial ischemia?
**Higher myocardial oxygen demand due to Thick LV wall**
CAD history may be prone to inferior wall hypokinesis
52
If you have MR in setting of Aortic Stenosis, what must be evaluated?
**Function MR = Secondary to AS**
- Why? Elevated LV systolic pressures
vs.
**Primary MR = Instrinic MV disease that will require repair**
53
What is a normal jet velocity across AV?
1.2 - 2.2 meters/second
54
What is a jet velocity across AV associated with Mild AS?
2.6 - 2.9 meters / second
55
What is a jet velocity across AV associated with Moderate AS?
**3.0 - 4.0 meters** / second
56
What is a jet velocity across AV associated with **Severe** AS?
**\> 4.0** meters /second
57
What **mean gradient** is associated with **mild AS**?
(Include American and European)
American \< 20 meters / second
European \< 30 meters / second
58
What mean gradient is associated with **Moderate AS**?
(Include American and European)
American 20 - 40 mmHg
European 30 - 50 mmHg
59
What mean gradient is associated with Severe AS?
(Include American and European)
American \> 40 mmHg
European \> 50 mmHg
60
What is a normal Aortic Valve size?
3 - 4 cm2
61
What is a valve size of **mild** AS?
\>1.5 - 2.5
62
What is a valve size of **moderate** AS?
1.0 - 1.5 cm2
63
What is a valve size of severe AS?
\< 1.0 cm2
64
What indexed ratio is mild AS?
\> 0.85
65
What indexed ratio is **moderate** AS?
0.6 - 0.85 cm2/m2
66
What indexed ratio is **severe** AS?
\< 0.6
67
What is a velocity ratio of mild AS?
\> 0.5
68
What is a velocity ratio of **moderate** AS?
0.25 - 0.5
69
What is a velocity ratio of **severe** AS?
\< 0.25
70
Does TEE measure Peak instantaneous or Peak to peak drop?
**Peak Instantaneous pressure drop (TEE) is higher**
Peak to peak (Cath) is lower
71
When you trace a gradient, what are you measuring?
Mean transaortic gradient = **Averages the instantaneous gradient** over the ejection time
72
What is the formula for mean pressure gradient to be estimated from peak velocity?
Mean PG = 2.4 (Vmax2)
73
How will Cardiac output affect your AS gradients?
High CO = Overestimate
Low CO = Underestimate
74
How will SVR affect your AS gradients?
Low SVR = Overestimate
High SVR = Underestimate
75
How will AI affect your gradients for AS?
AI = Overestimate the gradients
76
How will MR and MS affect your AS gradients?
Underestimate AS
77
The **anatomical** aortic valve area is determined by *_what?_*
Planimetry
78
The **functional** aortic valve area is determined by ***_what_***?
Doppler
79
What are the 3 doppler techniques to estimate AVA?
1. Continuity Equation
2. Simplified continuity equation
3. Velocity ratio
80
What is the velocity ratio (Dimensionless index) independent of?
Flow
81
What is the continuity equation based on?
**Conservation of mass**
(Blood flow through different orifices of a continuous vascular system is equal
82
What does the simplified continuity equation use?
What does it remove
Peak velocities
Removes *_LVOT diameter_*
83
What is **mild AS** from mild dimensionless index?
\> 0.5
84
What is **moderate AS** from mild dimensionless index?
0.25 - 0.5
85
What is **moderate AS** from mild dimensionless index?
\< 0.25
86
What is the formula for coninuity equation?
SV (LVOT) = SV (AV)
Area (LVOT) \* VTI (LVOT) = **Area (AV)** \* VTI (AV)
**Solve for AVA**
87
What is the Simplified Continuity equation?
AVA = *_**V(Max) \* CSA (LVOT)**_* / ***_V(Max) AV_***
88
What is the formula for dimensionless index?
VR = *_V (LVOT)*_ / _*V (AVA)_*
89
What is the formula for CSA of the LVOT?
CSA = πr2
= π(d/2)2
= 0.785 d2
90
When in the cardiac cycle do you measure LVOT diameter?
Where and how do we measure it?
**Mid - systole (Just before T wave)**
**Inner edge to Inner Edge**
91
When in the cardiac cycle do you measure Aortic Root and Ascending Aorta diameter?
**End - Diastole (Before R wave)**
Leading edge to leading edge
92
What two scenarios can you have Low Gradient AS?
1. **Low EF**
2. **Normal EF with MR or low diastolic volume**
93
What is low gradient AS, low EF defined as?
Aortic stenosis (AVA \<1.0 cm2)
- Transvalvular gradient of \<30 - 40 mmHg
- LV EF \< 40%
94
What is the pathophysiology of low gradient AS?
Insufficient forward flow from LV dysfunction to fully open the stenotic valve, resulting in a low gradient and estimated AVA
95
What is the key differentiation of Low Gradient AS?
**Key Question**
1. *_True AS_* by AVA (Reduced cusp mobility)
vs.
2. *_Pseudo AS_* which has reduced cusp opening (but normal AVA) from reduced flow
96
What is the key test to differentiate Low Gradient AS?
**Dobutamine Stress Echo**
97
How does a dobutamine stress echo help you differentiate true AS vs. pseudo AS in low gradient AS?
Alters SV and assessing changes in:
## Footnote
**1. Aortic velocity**
**2. Mean gradient**
**3. AVA**
98
What is the starting dose of dobutamine in low gradient AS?
**2.5 - 5.0 mcg/kg/mi**n by *_5.0 mcg/kg/min every 3 minutes_* to a maximum of **40 mcg/kg/min**
99
What is the cutoff for pseudo AS for dobutamine stress echo by:
## Footnote
**AVA (Absolute or relative value)**
1. Increase AVA by \>0.3 cm2 (Relative)
2. Increase AVA to over 1 (Absolute)
100
Why is Dobutamine Stress Echo done in terms of surgical outcomes?
If you identify a group with contractile reserve, those patients have **better surgical outcomes after aortic valve replacement**
101
What phase in the cardiac cycle does not truly exist in Aortic insufficiency?
**Isovolumetric relaxation**
(As the LV relaxes), even before the MV opens, the LV volume increases from AI flow
102
What happens to the pressure volume loop in AI?
LV filling enhanced (AI and MV inflow)
- Increased preload
- Higher contractile forces
- Raises SV
103
What are the two main etiologies of AI?
1. Intrinsic disease of the cusps
2. Root/Ascending disease causing secondary AI
104
How do we classify etiology of AI on echo?
Based on **cusp motion**
105
What is Type 1 AI?
Normal cusp motion but coapts at or above the annulus in the sinus of valsalva
106
How do we further subclassify AI into:
Type 1A
Normal cusp motion but coapts at or above the annulus in the sinus of valsalva **specifically dilatation of the STJ**
107
How do we further subclassify AI into:
Type 1B
Normal cusp motion but coapts at or above the annulus in the sinus of valsalva specifically dilatation of the **Sinus of Valsalva**
108
How do we further subclassify AI into:
Type 1C
Normal cusp motion but coapts at or above the annulus in the sinus of valsalva specifically **dilatation of the Annulus**
109
How do we further subclassify AI into:
## Footnote
**Type 1D**
Normal cusp motion but coapts at or above the annulus in the sinus of valsalva specifically **dilatation of the Cusp Fenestration**
110
How do we further subclassify AI into:
Type 2
Excessive Cusp Motion occurs when the body (belly) of the cusp falls below the AV annulus as with prolapse or flail cusps
111
How do we further subclassify AI into:
## Footnote
**Type 3**
**Restricted cusp motion from calcification** or *_rheumatic results in central malcoaptation_*
112
