Hjerte Flashcards
1
Q
Hvordan bedre cardiac vindu
A
- Armer over hodet
- Len over på ve. side
- Prøv å sitt foroverlent
2
Q
Cardiac UL - Focused questions
A
- Pericardial effusion
- Global function/contractility
- Signs of right ventricular strain
3
Q
Which ventricle lies more anterior/closer to the probe
A
The right ventricle (The heart is slightly anteriorly rotated)
4
Q
Which two views allow for four-chamber visualization and comparison of right and left ventricular cavity size?
A
The apical and subxiphoid views
5
Q
Probe positioning for subxiphoid/subcostal
A
Plce the probe in the subxiphoid position Aim toward the left shoulder and place the probe at a 15-degree angle to the chest wall. The probe indicator should be pointing toward the patient’s right (Start with the screen at maximum depth)
6
Q
Subxiphoid/subcostal - Orientation
A
7
Q
Tip for problem with visualizing the subcostal view (4)
A
- Try increasing the depth to its maximal level to make sure the beam is reaching the part of the thoracic cavity containing the heart
- Flatten the probe on the abdominal wall to make sure the beam is angling toward the left thoracic cavity
- Slide the probe over to the right to use the liver as an acoustic window and to get away from the stomach, which may be scattering the sound waves
- Have the patient bend his or her knees if possible. This helps relax the abdominal wall muscles and can sometimes make visualization clearer
8
Q
Parasternal long axis view - How
A
Assuming the long axis of the heart to be from the patient’s right shoulder to the left hip, the transducer probe should be placed in the third or fourth intercostal space, immediately left to the sternum
The probe indicator should be pointing toward the 5 o’clock/left hip position
9
Q
Which three points define the plane of the parasternal long axis view
(When these three structures are visualized simultaneously, the probe is oriented correctly along the long axis of the heart.)
A
- Mitral valve
- Aortic valve
- Cardiac apex
10
Q
Important function of parasternal long axis in relation to pericardial effusion
A
Can help distinguish pleural from pericardial effusions. Large pleural effusions can appear to surround the heart, but they will taper to the descending aorta, which can often be seen in the parasternal view. Pericardial effusions will cross anterior to the descending aorta.
(This is because the pleura will insert where the descending aorta travels through the thoracic cavity.)
11
Q
How to find the parasternal short-axis view
A
Assume the short axis to be from the patient’s left shoulder to the right hip.
The transducer probe should be placed in the 3rd or 4th intercostal space, immediately left of the sternum.
If the parasternal long-axis view has already been obtained, simply rotate the transducer 90 degrees clockwise toward the patient’s right hip. Usually this view visualizes the mitral valve in cross-section. By sliding toward the right shoulder the aortic valve can be seen and toward the left hip the heart’s apex.
12
Q
How to help find the parasternal long-axis view (4)
A
- Try angling the probe obliquely to sneak through the intercostal space
- Try sliding the probe along the 3rd or 4th intercostal space toward and away from the sternum. Occasionally, the long-axis view is not adajcent to the stenrum but more in the midline of the thoracic cavity
- Have the patient lie in the left lateral decubitus position to bring the heart closer to the chest wall and limit interference from the lung
- Have the patient have his arms over his head
13
Q
Tip for visualizing the parasternal short-axis view (2)
A
- Try sliding the probe in the intercostal space toward and away from the stenrum.
- Try angling the probe obliquely
- Try having the patient have his hands over his head
- If the patient can sit forward or be positioned in the left lateral decubitus position, the heart will be brought forrward in the chest and will be closer to the probe, making for easier scanning
14
Q
Parasternal short-axis - Name the three views
A
- Aortic valve
- Mitral valve
- Mid-ventricle (papillary muscle visible)
15
Q
Parasternal short-axis - Which level
A
Mitral valve
By tilting the transducer downward but staying perpendicular to the long axis of the heart, you will first arrive at the plane of the mitral valve. Here the mitral valve is seen orthogonally with its anterior as well as posterior leaflet. This view is ideal to observe the opening and closing motion of the mitral valve; this motion has been compared to a fish opening and closing its mouth.
The PSAX base view should not be used to assess LVF. You are too far at the base of the ventricle here. These segments are not representative.
16
Q
Parasternal short-axis - Which level
A
Aortic valve view
17
Q
Parasternal short-axis - Which level
A
Mid-ventricle / Papillary-muscle level
By tilting the transducer even further towards the apex you will gradually see the papillary muscles appearing. Now you are transecting the left ventricle nearly in the middle. The papillary muscle may vary in terms of size as well as position. The right ventricle is also seen in this view, but is more narrow here than on the PSAX LV base view. This view is ideal to inspect features such as left ventricular function (regional and global), the size of the ventricles, and characteristics of left ventricular hypertrophy.
18
Q
Orient the image, name the different structures
A
It is important to adjust the image so that the aortic root is seen as a round structure in which all three aortic valve cusps are visible. The appearance of the aortic valve during diastole resembles that of a “Mercedes star”.
Given good quality of the image, you will be able to visualize the origins of the coronary artery, especially that of the right coronary artery. The aorta is in the “center” of the image, surrounded by the left atrium, the interatrial septum, the right atrium, the right ventricle and the pulmonary artery (starting at the bottom and moving in clockwise direction). From here you can see all cusps of the aorta. Therefore this view is ideal to observe the opening and closing motion of the aortic valve. This view also enables you to estimate the size of the left atrium and detect interatrial septal defects (ASD). However, in most cases you will have to use an atypical short-axis view from a position that is one or two intercostal spaces lower in order to detect atrial septal defects. The PSAX base view should also be used to study the tricuspid valve and identify any membranous ventricular septal defect, pathologies of the right ventricular outflow tract (RVOT), or the pulmonary valve (PV). Use a modification of the PSAX base view to assess the PV and the pulmonary artery: direct the transducer more to the left and tilt it ventrally. Sometimes it may be necessary to obtain the image from a lower intercostal space. Here it is possible to see the bifurcation of the pulmonary artery and its branches. The right pulmonary artery is visualized here as it passes beneath the aortic arch. This view will also permit you to detect a patent ductus arteriosus (PDA).
19
Q
How to find the apical four-chamber view
A
Usually located along the T4-5 level or nipple line. Position the transducer at the patient’s PMI or about the 5th ICS, aiming toward the patient’s right shoulder.
The probe indicator should be pointed toward the patient’s right.
If possible, rotate the patient onto his or her left side to reduce any lung artifact and to bring the heart closer to the anterior chest wall.
20
Q
Tip for obtaining the apical four-chamber view
A
- Have the patient in left lateral decubitus position or sitting forward
- Have the patient have his hands above his head
- Sometimes sliding the probe around where you think the PMI might be will result in a recognizable image popping into view
- Try to start with a parasternal long-axis view, and slide the probe laterally along the chest wall until the apx is centered on the screen. Then adjust the angle and direction of the transducer to create an apical window
21
Q
Name the chambers in the A4C view
A
22
Q
How to measure the right and left ventricle diameter
Normal and abnormal values
A
Measure the width from the myocardial inner wall to septal inner wall at the level of the tricuspid and mitral valves.
Normally the ratio of right ventricle diameter to left ventricle diameter is < 0.5.
Some authors use > 0.7 and some > 1.0 to indicate a dilated right ventricle
(Abnormal movement of the septum away from the right ventricle / toward the left ventricle indicates increased right ventricular pressures. Normally the right ventricle is a low-pressure system, and therefore relaxation would mean the septum would bow away from the right ventricle.)
23
Q
Forkortelser - LVIDd og LVIDs
A
Left ventricular internal diameter end diastole and end systole.
Normal LVIDd: 3.5-5.6 cm
Normal LVIDs: 2.0-4.0 cm
24
Q
Forkortelser - IVSd og IVSs
A
Interventricular septal end diastole and end systole. The normal range is 0.6-1.1 cm.
The IVSd and IVPWd measurements are used to determine left ventricular hypertrophy, which is the thickening of the muscle of the left ventricle. LV hypertrophy is a marker for heart disease. In general, a measurement of 1.1-1.3 cm indicates mild hypertrophy, 1.4-1.6 cm indicates moderate hypertrophy, and 1.7 cm or more indicates severe hypertrophy.
25
Forkortelser - LVPWd og LWPWs
Left ventricular posterior wall end diastole and end systole. The normal range is 0.6-1.1 cm.
The IVSd and IVPWd measurements are used to determine left ventricular hypertrophy, which is the thickening of the muscle of the left ventricle. LV hypertrophy is a marker for heart disease. In general, a measurement of 1.1-1.3 cm indicates mild hypertrophy, 1.4-1.6 cm indicates moderate hypertrophy, and 1.7 cm or more indicates severe hypertrophy.
26
Forkortelser - LVOT
2D parasternal long-axis view † † Zoom mode † † Adjust gain to optimize the blood tissue interface †
Inner edge to inner edge
Mid-systole
Parallel and adjacent to the aortic valve or at the site of velocity measurement (see text)
DIameter is used to calculate a circular CSA
27
Forkortelser - RVAWd
Right ventricular anterior wall end diastole diameter
Measured in PSLX, M-mode.
When right ventricular anterior wall thickness was more than 4.0 mm, pulmonary hypertension was detected, with a sensitivity of 97.5% and a specificity of 90.9%. (-\> Hjelpe til å skille LE fra cor pulmonale)
28
Forkortelser - EPSS
E-point septal separation
The distance from the anterior mitral valve leafleft and the ventricular septum in early diastole.
The measurement is made in m-mode and is simply the closest the mitral valve gets to the septum in the cardiac cycle. In early diastole, the anterior mitral valve should approach or even touch the septum. In SHF, the ballooning heart with increased preload will pull valve away from the septum.
Like the LVEDD, the EPSS is a simple linear m-mode measurement obtained from the parasternal long axis view.
EPSS of \>7mm is thought to be an indication of poor LV function. Some use 1cm as the mark to increase their sensitivity for low ejection fraction. So, you can see that it should be a good indicator of LV function.
29
Forkortelser - AVA
Aortic valve area
Calculated based on
1. LVOT from PLAX
2. LVOT velocity and/or VTI from the 5-chamber or apical long axis view
3. The velocity of VTI at the aortic valve from the 5 chamber or apical long axis view
30
EPSS - Values
a. Normal
b. Left ventricular dysfunction
c. Severe left ventricular dysfunction
a. \< 6 mm
b. \> 7 mm
c. \> 13 mm
31
EPSS can reliably estiamte left ventricular function in patients with aortic stenosis, but is usually misleading in patients with ... (2)
1. Significant MS
2. Significant AR
32
Fractional shortening - How to
Measure left ventricle during diastole and systole. Measure left ventricular end-diastolic diameter (LVEDD) and LVESD with M-mode at the level of the papillary muscles at PSLX or PSSX.
(FS) = (LVEDD-LVESD)/LVEDD
(Measure LVEDD and LVESD at internal diameter)
33
Fractional shortening (FS)
a. Normal value, correspond to which EF%
b. Severe left ventricular dysfunction, correspond to which EF%
a. \>25% (= \>55%)
b. \< 15% (= \<30%)
34
Fractional shortening (FS) - Limitations for estimating EF
1. RWMAs
2. Oddly shaped ventricles
3. Inaccurate if the M-mode cursor is not exactly perpendicualr to the septum and posterior wall
35
Patients with significant MR may have a hypercontractile LV bu a very low CO, and patients with dilated cardiomyopathy may have a good SV despite a low EF. When these clinical conditions are known or suspecte, it may be reasonable to correlate left ventricular EF with measurements of stroke volume. Which two measurements are necessary for this
1. Area of LVOT
2. Velocity time integral (VTI) of the flow through the aortic valve during systole
36
Left ventricular EF may not be a good indicator of cardiac output in patients with (4)
1. AS
2. MR
3. Concentric left ventricular hypertrophy (LVH)
4. Isolated left ventricular diastolic dysfunction (Make up 50% of patients with overt CHF)
37
Left atrial enlargement - Causes
1. Left ventricular diastolic dysfunction (Most common)
2. Volume overload from valvular regurgitation
3. High output states like chronic anemia
38
Left atrial enlargement
a. Normal value
b. How to measure
a. \< 4 cm / Significantly larger than the proximal aortic diameter
b. End-systolic atrial diameter (internal) in PSLX
39
Findings with LVH
1. LV internal chamber diameter \> 55-60 mm
2. Wall thickness in end-diastole \> 12 mm
40
Sonographic predictors of hypovolemia with fluid responsiveness (5)
1. IVC size and respiratory changes
2. Changes in cardiac output with respiratory cycle or passive leg raise
3. Hyperdynamic cardiac function
4. Small left ventricular end-diastolic area
5. left ventricular systolic collapse
41
Hypovolemia - Findings of IVC with
a. Low CVP pressure (0-5 mmHg)
b. High CVP pressure (\>15 mmHg)
a. IVC size \< 2 cm with \> 50% collapse on inspiration/sniff test
b. IVC size \> 2 cm with no collapse on inspiration/sniff test and dilated hepatic vein
(The inbetween is less accurate)
(Collapse \> 50% indicate pressure \< 10 mmHg)
(Say in text \< 1 cm is compatible with hypovolemia)
42
IVC size and collapsibility - May be misleading in ..
1. COPD, right heart failure or other causes of chronically elevated RA pressure
43
IVC size in children, which ratio correlate with low CVP
Equal to or more than the aortic diameter and an IVC/aorta ratio of equal to or less than 0.8 correlates with low CVP
44
Acute dyspnea - IVC finding which is 96% specific for acute heart failure
IVC collapsibility \< 15% and an IVC/aorta ratio \> 1.2
45
Children - Evaluation for dehydration. AN IVC/aorta ratio of ... has been found to be a relatively good indicator of significant dehydration requiring IV rehydration (Sensitivity 86%, specificity 56%)
\< 0.8
46
Definition of a hyperdynamic left ventricle
Near or complte obliteration of the left ventricular cavity, meaning that the endocardial surfaces of the septum and posterior wall come in close contact with each other.
47
'Kissing papillary muscle sign' - What, significance
Papillary muscles touching in PSSX.
100% senssitive for detecting hypovolemia, but only 30% specific for predicting volume responsiveness
48
How to use ventricular volume to predict hypovolemia
In parasternal short-axis over papillary muscles measure the cross-sectional area in end-diastole by tracing the endocardial border
\< 10 cm^2 generally indicates hypovolemia
49
Top 2 causes of acute MR
1. Rupture of chordae tendinae or papillary muscles secondary to AMI (More probably with inferior wall MI with involvement of the RCA)
2. Infective endocarditis
50
Mitral valve
a. Where to visualize the two leaflets
b. Findings if ruptured
a. PSLX and PSSX
b. Clearly visible flail leaflet if the entire papillary muscle is ruptured
(Normal valve leaflets should appear thin, produce uniform echoes, and be unrestricted in their motion. Thickened, immobile valve leaflets are often associated with regurgitation)
51
Color flow doppler is the key to detecting regurgitation and the easiest way to determine the sverity of regurgitation. Mitral regurgitation is severe if ...
.. the regurgitant jet area fills \> 40% of the left atrial area
52
AR is an acute process in about 20% of cases and most commonly caused by ... (2)
1. Infective endocarditis
2. Proximal aortic dissection
53
AR - Patients with chronic AR are more likely to have obvious abnormalities such as ...
1. Thickened and immobile valve leaflets
2. LV enlargement
(Those with acute AR may have a normal-sized left ventricle and thin valve leaflets on 2D imaging.)
54
Aortic valve leaflets
a. Normal leaflets are best visualized in which view
b. Normal leaflets should appear
a. PSLX
b. Thin, produce uniform echoes, be unrestricted in their motion, coapt in the center of the aortic root during diastole and snap open and lie parallel to the aortic wall during systole
55
AR
a. Screening test
b. Severe aortic regurgitation
a. Color flow doppler in A5C, measurement of the maximal proximal jet width and its ratio to the LVOT diameter
b. \> 65% is diagnostic of severe AR
56
Where to measure LVOT diameter
In PSLX in mid-systole, from the white-black interface of the septal endocardium to the anterior mitral leaflet, parallel to the aortic valve plane and within 5-10 mm from the valve orifice
57
Signs of aortic dissection on TTE (4)
1. Pericardial effusion (Sign of imminent mortality without surgical intervention)
2. Presence of ascending aorta involvement
3. Presence of descending aorta involvement
4. Presence of abdominal aorta involvement
58
Cardiac windows - Which views are best when the patient exhales and which are best when the patient inhales
Exhale -\> parasternal and apical
Inhale -\> Subcostal
59
Basic goals of point-of-care US (7)
Basic goals of point-of-care US
1. Identifying moderate or large pericardial effusions
2. Identifying gross cardiac activity or cardiac standstill
3. Assessing relative and gross chamber sizes (A4C)
4. Assessing the EF by 2D vsiual estimation (Subcostal, PSLX, A4C)
5. Measuring EPSS to estimate EF
6. Evaluating gross valvular motion (PSLX, PSSX)
7. Assessing volume status by IVC size and collapsibility (subcostal sagittal view)
60
Where is the IVC measured in sagittal view
3-4 cm distal to its junction with the atrium or 2-cm distal to the entry of the hepatic veins
61
RWMA - PSLX (3)
Anterior and apical = LAD
Mid-posterior = Left circumflex artery
Basal posterior = Posterior descending artery of RCA and Cx
62
RWMA - - PSSX, midpapillary level (3)
Septal & anterior & anterolateral = LAD
Posterolateral = LCx
Inferior/posteriolateral = Posterior descending artery of RCA and LCx
63
RWMA - A4C (2)
Lateral & apical = LAD
Basal septal & mid septal = Posterior descending artery of RCA and LCx
64
Apical five chamber view - How to obtain
Beginning frmo the apical four-chamber view, the transducer is tilted or swept slightly anterior, to allow visualization of the LVOT (proximal aorta and aortic valve), which is the "5th chamber".
65
A5C view - Applications
1. Primary view for measuring Doppler flow across the LVOT and for calculation of stroke volume and CO
2. Good for differentiating right-left ventricle if uncertain in a A4C view
66
A2C view - How to obtain
Obtain the A4C view -\> Rotate the transducer about 60 degrees counter-clockwise
67
How to obtain the A3C view
A4C view -\> rotate counterclockwise beyond the A2C view until the aortic valve is visualized on the right side of the image (About 90 degrees).
68
Suprasternal view
1. How to obtain
2. Allows visualization of
1. Place the transducer in the sternal notch with the transducer marker pointed toward the patient's right scapula (if non-cardiology preset) and the transducer aimed as far anterior as possible
2. Aortic arch with its three main branches - Brachiocephalic, left carotid, left subclavian. used for visualization of aortic aneurysm or dissection
69
Methods of estimating left ventricular structure and function
1. Visual estimation of EF
2. EPSS
3. 2D measurements of LV chamber area/volume to calculate EF
4. M-mode measurements to calculate EF and LV mass
5. Doppler flow measurements to calculte SV and CO
70
Limitations for measuring/estimating EF
1. Technical
2. Patient-related
1. Poor virews, oblique, foreshortened
2. RWMAs, tachycardias, BBB
71
How to visually estimate LV EF
Obtain an A4C view (or any view for gross estimation) Does the volume of blood ejected from the LV appear to be \>50-55% (Normal), 30-50% (Mild-to-moderate reduction in EF) or \< 25% (severely reduced EF).
72
Abnormal values - LV diastolic diameter (PLAX view)
\> 5.3 cm (female), \> 5.9 cm male
73
Abnormal values - Septal thickness and/or posterior wall thickness in diastole (PLAX view)
(Moderate to severely abnormal values. LV mass/BSA is more accurate for diagnosing LVH)
\> 1.2 cm (female)
\> 1.3 cm (male)
74
EPSS - Abnormal value
\> 7 mm
75
Abnormal value - Fractional shortening (FS) (PLAX view)
\> 25%
76
Abnormal values - Left atrium diameter (PLAX view)
\> 4.0 cm
(Should be measured in systole when/where it is largest)
(The left atrium often distends in other dimensions while the AP diameter remains normal)
77
Abnormal values - Left atrium area (A4C view)
\> 20 cm^2
78
Abnormal values - RV free wall thickness (Subcostal view)
\> 0.5 cm
79
Abnormal values - Ascending aorta diameter (PLAX)
\> 3.5 cm
80
Aortic root
1. Where to measure, abnormal value
2. Causes of increased diameter
1. PLAX, above left atrium, when/where largest
2. Most often age-related change. Aortic aneurysm, aortic dissection.
81
Right ventricular dimensions. When the right ventricle becomes equal or larger in size than the left ventricle, it si easy to recognize RV enlargement. In more subtle cases, it is useful to perform measurements of the RV. Normal measurements of the mid-RV diameter in diastole is 1. and of the basal RV diameter is 2.
Which other two findings are caused by significantly elevated right-sided pressure and should be looked for if the RV is enlarged 3.
1. \> 3.5 cm
2. \> 4 cm
3. Bowing of the IVS and significant tricuspid regurgitation
82
An M-mode tracing at the mitral valve level in the PLAX view allows measurements of the (5)
1. RV free wall
2. IVS
3. Mitral valve leaflets
4. Posterior LV wall
5. Pericardium
83
EPSS - An M-mode tracing through the anterior leaflet of the mitral valve produces a double peak pattern, what does these peaks represent
The first peak/E-point is caused by passive filling of the left ventricle in early diastole.
The second peak/A-point is caused by atrial contraction.
(This double peak pattern is evidence of sinus rhythm.)
84
EPSS
1. What
2. A large EPSS reflects LV systolic dysfunction in the absence of (2)
3. Normal value
4. Value equal to EF \< 50%
5. Value equal to EF \< 35%
1. Distance between the E-point and the IVS
2. MS or AR
3. \< 6 mm
4. \> 7 mm
5. \> 13 mm
85
M-mode over PSAX mid-papillary level or PSLX proximal to mitral valve leaflets
1. Which measurements
2. Which calculations are possible with these measurements
1. The following in systole and diastole - IVS, LVID and PVPW
2. LV mass, diagnostis of concentric or eccentric LVH
3. LV fractional shortening / EF
(Note that determining LV contractility using these measurements is technically called FS but most modern US machines report EF rather than FS when these measurements are made, because EF is a more familiar term and there is a linear correlation between EF and FS)
86
M-mode assessment of the IVC
1. If the CVP is normal (\< 10 mmHg), the IVC will ...
2. If the CVP is elevated (\> 10 mmHg), the IVC will ...
1. \< 2.0 cm (Most often), collapse \> 50% with inspiration/sniff
2. \> 2.0 cm, collapse \< 50% or not at all, dilated hepatic veins
(Taken from the subcostal long axis view)
87
Color doppler - Optimizing the color flow image is accomplished by using the highest possible velocity scale. How can this be accomplished/facilitated?
By decreasing the size of the color box, this increases pulse repetition frequency (PRF) and allows more accurate depiction of high-frequency flow without artifacts.
88
Bruksområder for spectral doppler
1. PW
2. CW
3. TDI
1. Flow through the LVOT to calculte the left ventricular stroke volume, document transmitral flow patterns to evaluate LV diastolic function
2. To measure higher flow rates through stenotic or regurgitant valves. To measure TR to estimate RV systolic pressure (RVSP) and to measure flow rates through stenotic lesions for valve area calculations
3. To measure the movement of the mitral annulus during diastole, to assess LV diastolic function
89
How to measure stroke volume
1. Cross-sectional area of the LVOT from PLAX
2. VTI by Doppler flow through LVOT in A5C/A3C
(The doppler waveform is traced to measure the VTI. The product of the VTI and the area equals the stroke volume)
90
1. How is the peak velocity of the LVOT related to stroke volume
2. Clinical relevance
1. Vpeak or Vmax (peak velocity of the pulsed Doppler blood flow) has a linear correlation with stroke volume.
2. Visual estimation or measurements of changes in Vpeak, after passive leg raising, with respirations or after a fluid challenge may be helpful in predicting fluid responsiveness.
91
Cardiac tamponade - Findings
1. Pericardial effusion
2. Right atrial systolic collapse
3. Right ventricle diastolic collapse
4. Lack of respiratory variation in IVC and hepatic veins
5. \>25% variation in diastolic filling in right/left ventricle with expiration/inspiration (Use A4C and PWD)
92
Pericardial effusion - Size / severity classification
1. Small - Anechoic space \< 1 cm thick and are often localized, usually between the posterior pericardium and left ventricular epicardium
2. Large - \> 1.5 cm, usually completely surround t he heart.
93
Pericardial volume up to .... may be normal
50 ml
94
Findings for pulmonary embolism
1. Thrombus in the right heart
2. RV dilation (Normal end-diastolic diameter in A4C is \< 3.5 cm at mid and \< 4 cm at the base of the ventricle)
3. RV hypokinesis
4. TR regurgitation
5. Abnormal septal motion
95
RV - Normal ratio to left ventricle
Normal 0.5-10
\> 1.0 is seen with significant RV enlargement
(The right ventricle may be round in shape with significant enlargement)
96
PE - McConnell's sign
Diffuse hypokinesis of the RV free wall with apical sparing
(Described as right apex flirting)
(A very specific but insensitive indicator of PE)
97
PE - Septal flattening/D-sign
Septal motion toward the LV in PSSX
(A blood clot in the lung may cause decreased venous return to the left heart. This may result in decreased LVEDD as well as "paradoxical septal motion". The normal IVS relaxes toward the RV in diastole. With increased right end-diastolic pressures and decreased left-sided pressures, abnormal motion of the septum in diastole may be visaulized. May also be observed in systole, but is more pronounced in diastole. Especially prominent in the acute phase of massive PE)
98
Tricuspid regurgitation may occur when pulmonary artery pressure exceed RV end-diastolic (right atrial) pressures.
1. How to obtain tricuspid regurgitation velocity measurement
2. How many % with PE will have measurable TR
3. Normal pulmonary artery systolic pressure
4. Cutoff values for diagnosis of PE
1. A4C view, PWD over TR regurgitation
2. 90%
(Though many healthy will have trivial TR)
3. 25 mmHg corresponding to \< 2 m/s
4. \> 2.5-2.7 m/s
99
PE - TR
1. Other causes of significant TR
2. How to differentiate
1. COPD, primary pulmonary artery HT, RV infarct
2. The acutely strained right-sided heart rarely has the muscle mass to elevate pulmonary artery pressure into an extremely high range and values well over 40 mmHg should suggest a chronic elevation.
An increase in muscle mass on measurement of the right ventricular free wall may also indicate a more chronic etiology for RV strain as opposed to a thin, acutely dilated right ventricle.
100
1. What is the normal thickness of the right ventricular free wall.
2. When is it generally considered hypertrophied
1. 2.4 +- 0.5 mm
2. \> 5 mm
101
It is best to use a combination of findings to get the most accurate picture of overall cardiac function, including (6)
1. Visual estimation of LV function
2. EPSS
3. Visual inspection of the valves
4. IVC size and collapsability
5. Pulmonary US findings
6. Simple measurements of systolic and diastolic function
102
Method of discs/Modified Simpson's rule for estimating EF
Document the change in LV volume between diastole and systole by tracing the endocardial border.
Calculations are most accurate if measurements are performed in both A4C and A2C views
103
How many % of patients with clinical heart failure have isolated diastolic dysfunction with normal left ventricular systolic function
50%
104
What is the most common cause of left atrial enlargement
Diastolic dysfunction
105
Which two auxiliary signs can you look for when considering diastolic dysfunction
1. LVH
2. Left atrial enlargement (LAE)
106
Diastolic dysfunction - How to perform the measurements
1. in A4C use PWD of left ventricular filling (transmitral flow/mitral inflow) and TDI of the mitral annulus.
- Transmitral: The measuring gate is placed just inside the left ventricle at the tips of the mitral valve leaflets
- TDI: TDI gate over the septal portion of the mitral annulus
107
Diastolic dysfunction - How to classify into the 4 categories
Do transmitral doppler to get E and A and TDI of mitral annulus movement to get e' and a'.
1. Normal
- E\>A
- Deceleration time (DT) \> 160 ms
- e'\>a'
- Normal e' \> 8 cm/s, less is diagnostic of diastolic dysfunction
2. Delayed relaxation / DD degree I
- E \< A
- DT \> 240 ms (often)
- e' \< a'
3. Pseudonormal / DD degree II
- E \> A
- DT \< 160 ms
- e' \< 8 cm/s
4. Restrictive pattern / DD degree III
- E\>\>A (ratio \> 2)
- DT \< 160 ms (at least)
- e' \< 8 cm/s
-
108
LVH may be concentric or eccentric - What is the difference
Patients with concentric hypertrophy have thick left ventricular walls.
Patients with eccentric hypertrophy have a large left ventricular internal diameter (LVID)
109
How to identify and classify LVH using normogram
Measure LVID and mean LVPW and IVS (cm) -\> Plot into normogram to get normal LV mass, and hypertrophy. Hypertrophy can then be distinguished between eccentric and concentric
The measurements are made in PLAX in diastole using M-mode
(P. 141 in emergency ultrasound)
110
Hypertrophic cardiomyopathy is the leading cause of sudden cardiac death in preadolescents and adolescents - Which two types can this entity be separated into
1. Obstructive hypertrophic cardiomyopathy
- Asymmetric septal hypertrophy. The key finding is that the IVS is more than twice as thick as the posterior wall. Can cause dynamic obstruction
2. Non-obstructive cardiomyopathy
-
(Both types are at risk of arrhythmogenic sudden death)
111
Signs of significant volume depletion on cardiac ultrasound
1. Hyperdynamic left ventricle
2. Small LV end-diastolic area (\< 10 cm^2) and/or complete obliteration of the LV during systole ('Kissing papillary muscle sign')
(Ancillary findings are a small IVC that measures \< 10 mm in dimaeter at its largest during the respiratory cycle)
112
Fluid responsiveness vs CVP
Fluid responsiveness = A positive hemodynamic response (increase in stroke volume of at least 15% with a fluid bolus of 500 ml crystalloid
Thus can have low CVP, but still not be fluid responsive. CVP is in fact proven to be a poor predictor of fluid responsiveness. 50% of patients with septic shock are not fluid responsive
113
What is the only finding that has been shown to predict fluid responsiveness in non-ventilated patients
An increase in stroke volume of more than 15% with passive leg raise
114
Which valvular abnormality can aortic dissection be associated with
AR
115
With acute valvular disease the heart may look grossly normal or just hyperdynamic. Which findings are chronic severe valvuar disease associated with
1. Significant cardiac dysfunction
2. Chamber enlargement
(-\> It is important to consider assessing valvular function in patients with these findings)
116
How to essentially rule out AS using visual estimation with 2D US (3)
1. Widely opened valvular leaflets on PLAX
2. Visualize AV in PSSX in open and closed position to rule out bicuspid AV - easiest to see in open position
(Bicuspid aortic valves often have fusion of the right and lef coronary cusps with a raphe replacing the inferior commissure, so the valve may look normal in the closed position)
3. Stenotic valves usually have significant thickening and calcification, so a grossly abnormal valve should increase suspicion for AS (Sensitive, but unspecific finding)
117
Significant aortic thickening and calcific changes are present in about ... % of elderly patients
Prevalence of AS in the same age group
25%
A couple %
118
How to calculate the aortic valve area
By using CWD measurements in PLAX at the level of the valve orifice and at the level of the LVOT
These measurements are placed into the continuity equation and the valve area is calculated
119
Aortic valve area
1. Mild AS
2. Moderate AS
3. Severe AS
1. 1-1.5 cm^2
2. 0.75-1 cm^2
3. \< 0.75 cm^2
120
Ways of determining significant AS (4)
1. Visually in 2D
2. Calculation of aortic valve area
3. Measure the maximal aortic jet velocity
4. Measure the maximal aortic cusp separation
121
How to measure the maximal aortic jet velocity to determine significant AS
Abnormal findings
= The single highest velocity jet of flow that can be measured in the aortic valve region from any window using CW doppler
3-4 m/s = mild AS
\> 4 m/s = sevre AS
122
Methods for determining significant AS - Measuring the maximal aortic cusp separation - How to
Abnormal values
Good quality PLAX with open valve cusps and porximal aorta aligned horizontally on the image -\>
Perform M-mode through the aortic valve cusps (Normal aortic valve cusps are in close proximity to the walls of the proximal aorta when the valve is open and meet in the middle of the aorta when the valve is closed, giving a distinct M-mode pattern)
Normal = \> 15 mm
Mild AS = 12-15 mm
Severe AS = \< 8 mm
123
How to estimate for MS (2)
1. Visual estimation
2. Measuring area of mitral valve orifice
124
MS - How to visually estimate
1. PLAX - Look for widely opened valve
2. A stenotic mitral valve has a distinctive appearance with ballooning and a "hockey stick" shaped anterior leaflet during diastole (photo)
125
MS - Visual estimation - Pitfall
Decreased LV function causes decreased mitral valve opening (Mechanism of measuring EPSS).
Therefore, providers must differentiate mitral stenosis from severe LV dysfunction by assessing the ventricle and the appearance of the valve during diastole.
126
MS - How to assess by area of mitral valve orifice
Values
PSSX over mitral valve
Trace the mitral valve at the point of maximal opening, at the level of the tips of the mitral valve
Normal = 4-6 cm^2
Moderate MS = 1-1.5 cm^2
Severe MS = \< 1 cm^2
127
1. What is the primary initial ultrasound test for valvular regurgitation
2. What are the two most important factors when screening for regurgitant flow with Color doppler imaging
1. Color Doppler
2. The angle of interrogation and the scale
- The color scale is optimal when it is adjusted to the highest possible velocity that still allows visualization of the regurgitation jet. Decreasing the size of the sampling box will allow the scale to be increased.
128
Valvular regurgitation - In which views are the mitral valve best evaluated
1. A4C
2. PLAX
129
Valvular regurgitation - In which views are the aortic valve best evaluated
PLAX
130
Valvular regurgitation - In which views are the tricuspid valve best evaluated
1. A4C
2. PSSX - Over aortic valve
131
Valvular regurgitation - In which views are the pulmonary valve best evaluated
PSSX
132
In which valves are there normally some small regurgitation and how does it look/appear
Mitral and tricuspid
(Not in aortic or pulmonary)
(Will be seen as a so-called "physiologic" regurgitation (with a short thin regurgitant jet)
133
How to identify moderate/severe mitral or tricuspid regurgitation
Large regurgitant jet area (a long, wide jet)
Regurgitant jets that occup \> 40% of the atrial area and/or extend to the opposite wall of the atria are considered severe
(Vena contracta = neck of jet)
134
Explain central vs eccentric regurgitant jet and pitfall
Central = Clearly visualized in the center of the atria
Eccentric = Not clearly visualized in the center
-Typically seen with flail leaflets or leaflet prolapse and are directed into the wall of the receiving chamber
Eccentric jets appear smaller in area than free jets, even whent he regurgitant orifice area is the same, so their hemodynamic signficance may be misjudged.
135
Aortic regurgitation - How to recognize severe AR
Regurgitant jets that occupy \> 65% of the height of the LVOT are considered severe
(The severity of aortic regurgitation is based on the regurgitant jet height (width) and the ratio of the jet height to the height (width) of the LVOT)
136
How to measure the LVOT diameter
137
Define hypokinesis, akinesis and dyskinesis
Hypokinesis - Decreased ventricular wall thickening and motion
Akinesis - Absent
Dyskinesia - Paradoxical motion of the wall - outward motion of the wall during systole
138
Ultrasound findings of chronic left ventricular infarction
1. Dilated left ventricle
2. Global wall motion abnormalities
3. Thinning of the ventricular wall - \< 7 mm or 30% less than the adjacent normal wall
4. Increased echogenicity of the segment due to fibrotic changes
139
How to measure aortic root diameter
Leading edge to leading edge (Outer edge one side to inner edge on the other side).
140
Proximal aortic dissection - Findings
1. Dilated aortic root (\> 3.5 cm) (PLAX)
2. Intimal flap in aortic root
3. Intimal flap in descending aorta seen posterior in the image in PLAX
4. Intimal flap in aortic arch on suprasternal view
(\*Intimal flap mentioned above can be seen as intimal flap or two lumens (false and true with different flow patterns on doppler))
141
Ascending aortic aneurysm - Findings
1. Dilation of the ascending aorta \> 1.5 times the normal segment
(Measure at several levels - at the aortic annulus, aortic leaflet tips, ascending aorta, aortic arch and descending aorta)
(Ofen coexist with aortic dissection)
(True vs false aneurysm - all layers or just penetration of intima and media)
(Most thoracic aneurysms are fusiform, but may be saccular)
142
Aortic aneuryms - If the thoracic aorta is measured at ... cm, then obtan cardiothoracic surgery consultation
5-6 cm
143
Intracardiac thrombus - Appearance
Can be hyper-, iso- or even hypoechoic.
Usually laminated with the layers paralleling the chamber wall.
(Near-field or TGCS may have to be adjusted to visualize suspected areas)
144
Which structures must be distinguished from thrombus (3)
1. Left atrial appendages
2. Right atrial chiari network (The delicate freely mobile membranous structure in the RA)
3. Right ventricular moderator bands
145
Identify the structure on the image
Findings of irregularities on valvular surfaces should prompt further investigation and consultation for more definitive diagnosis.
Vegetations may be echogenic or isoechoic and have an irregular appearance.
Laminated or pedunculated attachments to the leaflet of the valve should prompt suspicion.
In general, valves does not restrict valvular motion but some valve leaflets may not coapt together correctly.
(typical appearance of nromal valves include smooth echogenic leaflets. Refer all suspected cases for TEE and cardiology consultation)
146
How is transmitral flow and septal annulus movement related to LV end-diastolic pressure (LVEDP) / pulmonary capillary wedge pressure (PCWP)
