US, Echocardiography, Venous Duplex US Flashcards
Ultrasound aka?
AKA sonography, ultrasonography
Developed in mid-20th century
Narrow beam of high-frequency sound waves
Reflected back (echoed) to the handheld transducer
Reflected back differently by different densities
With US, solid organs are __________?
echogenic (white)
With US, fluid filled cysts and fluid are ____-____(echo lucent or anechoic) because they do not reflect
echo-free ( black)
US is not useful for ___ and ____?
air
bone
Not as clear an image as CT
US advantages?
No radiation
Good for obstetric, gynecological, pediatric and testicular conditions
Can view structures at any angle
Less expensive than CT, MRI
Can be performed portably, at bedside
Real-time view
Heart, fetus and other structures
Newer models – better resolution and less expensive
May become part of routine screens in office
US disadvantages?
Takes longer to complete
Most take 20-30 minutes
Quality is operator dependent
- Accuracy is variable
- Transducer angle varies – not always along strict anatomic planes
- More difficult to interpret, need to look at surrounding structures
Some tissues are isoechoic
-Reflection is the same though different structures
look similar to surrounding tissue
Some tissues obscured by overlying structures
-Ribs obscure underlying portions of spleen or liver
Quality of image reduced by thick adipose tissue
-thin people easier to look at
Cannot look at bones – too much reflection to see detail
Images that are close to being in the _____ plane should be presented and viewed as if the viewer is standing at the ____ of the patient’s bed (Pt’s right is to viewer’s left)
axial
foot
axial view, we are look up throguht the feet
Images that are close to the ________ plane are shown as if the viewer is looking at those sections from the _________ of the supine patient, with the head of the patient to the viewer’s left.
sagital
right side
Aortic Aneurysm etiologies ?
Atherosclerosis
Infection (mycotic) - rare
Aortic Aneurysm blood flow becomes _________.
turbulent
Aortic Aneurysm can be ________ or ________
fusiform, saccular
Aortic Aneurysm may be found incidentally by?
pulsatile mass on abdominal exam
Or patient can be symptomatic
Abdominal or back pain
Complications with AA?
leakage or rupture
AA USPSTF?
once for all men 65-75 who have ever smokedp
AA medicare coverage?
all men, once, upon receiving Medicare
US of AA?
evaluate for size and determines size
Aortic dissection 3 layers?
Intima – thin, smooth inner layer
Media – thicker, muscular
Adventitia – outer layer
Dissection is a separation of the layers
Aortic dissection patho?
Dissection is a separation of the layers
False lumen forms
Blood can flow through it or thrombose
Patients present with sudden “tearing” chest pain
DeBakey Type 1?
Type I – ascending and descending aorta
Originates just above aortic valve
May extend to abdominal aorta
part of A
DeBakey Type 2?
Type II – only the ascending
Originates just above the aortic valve
part of A
DeBakey Type 3?
Type III – only the descending
Originates distal to the left subclavian artery
May extend to abdominal aorta
part of B
Stanford classification?
Type A – ascending
Type B – descending
AD - If carotid arteries are involved, what signs and symptoms are we going to see?
CVA
AD - If superior mesenteric artery involved, what signs and symptoms are we going to see?
bowel ischemia
AD - If coronary arteries involved , what signs and symptoms are we going to see?
MI
For aortic dissection ________________ can be used, but most often diagnosed with _____________ (CTA).
echocardiography
CT angiography
MRI is too time-consuming
US cannot demonstrate aortic branches well
US is not good at determining ____ _____ in retroperitoneum.
free blood
IF AD In symptomatic patients with uncertain diagnosis– do __, not __.
do a CT not a US
is the patient is stable and their kidneys working well then - do a CTA better and more useful in the situation
acutely we use US
Echocardiography -type- M-mode?
Narrow US beam directed at cardiac structures
Observed over time - Time-motion study of structures
Considered to be obsolete by many, but an efficient way to record multiple cardiac cycles
Real time 2D
Real time 3D
Echocardiography -type- - color flow doppler?
Numerous sample volumes are overlaid on a 2-D echocardiogram and the direction of flow is recorded on the screen as either red or blue, depending on whether the flow direction was towards or away from the transducer. Some indication of the velocity is given by the brightness of the color. Flow which is turbulent, having no definite direction, is displayed as a third color, e.g. green or yellow.
blue is away
Echocardiography-types- TTE?
Transthoracic echocardiography:
Close to anterior heart
A type of 2D real-time
Echocardiography-types- TEE?
Transesophageal echocardiography
better images of STABLE aneurysm
Oral or nasogastric probe
Close to posterior heart
TEE?
invasively
Endoscopic ultrasound transducer
Inserted orally or nasogastric, advanced into esophagus
Good for evaluating posterior heart
Can be done at bedside
Indications for Echocardiography? US of heart indications?
Ventricular function
Wall thickness and motion
Valvular heart disease -
movement of leaflets, blood flow
Atrial septal defect
Ventricular septal defect
Pericarditis
Pericardial effusion
Pericardial effusion vs. pleural
effusion
Cardiac tamponade
Aortic dissection (but CT angiography faster)
Heart failure can affect?
wall thickness
wall motion
Echo - Ejection fraction?
Measurement of how much blood the LV pumps out with each contraction
many ways to determine EF but US is the mainstay - standard
Normal EF?
55-70%
E.g. of 60 means 60% of total amount of blood in LV is pumped out with each contraction
EF of 40-55% indicates?
damage - previous MI or from heart failure
EF of +75% indicates?
Hypertrophic Cardiomyopathy - HOCM
Preserved ejection fraction (HFpEF) – diastolic heart failure?
Heart contracts normally, but ventricles do not relax during systole
Ventricles are thick and stiff, hold a smaller amount of blood
Percentage is good, but the overall amount is deficient
cannot fill
Reduced ejection fraction (HFREF) – systolic heart failure?
Heart does not contract effectively during systole
Deficient amount of blood pumped
can get the blood out
cannot squeeze
Rheumatic and degenerative changes can affect?
Leaflet function
blood flow
Congenital abnormalities that affect blood flow?
ASD
VSDp
Pericarditis patho?
Inflammation of the sac around the heart
Pericardial Effusion patho?
Collection of fluid in the pericardial sac
Can be difficult to determine effusion by CXR
Echo helpful in diagnosing pericardial effusion
Reflection off heart and off layer of fluid are different
Pericardial Tamponade patho?
Acute increase of fluid in the pericardial space.
This can be caused by chest trauma, bacterial infection, myocardial rupture, and other occurences that affect the heart’s ability to fill during diastole.
Ejection fraction drops and the patient can develop a cardiac crisis.
Immediate treatment is recommended which may be by pericardiocentesis or by surgery.
By 2D echocardiography one can note the “swinging heart” inside of the pericardial sac.
what is the modality of choice for evaluation of DVT? what did it used to be?
US
used to be venogram - contrast material injected
US used no contrast material, noninvasive, no pa
Venous Duplex US sensitivity and specificity?
sensitivity - 95%
specificity - 98%
DVT in what locations puts a patient at risk for PE?
popliteal and common femoral veins
DVT of the ____ is not a risk factor for PE, but is a risk for extension of thrombus into deep veins of the thigh
calf
lest risk of PE is clot is below the knee
Venous Duplex method / procedure?
Pt is supine, slight reverse Trendelenberg position
Examine from inguinal ligament to popliteal fossa
Popliteal area examined with patient prone, knee slightly flexed
When using Venous Duplex in evaluating a DVT be sure to compress and release vein every _ cm?
1
When compressing a artery when examine for DVT the ______ should maintain its lumen, and a ____ should compress or “wink”.
artery
vein should wink
When looking for a DVT and a clot is present, the vein will require more _______ to compress or it will not compress at all.
pressure
when technician put pressure on the veins and arteries the artery should not collapse cuSE THE HIGH PRESSURE IN THE ARTERIAL SYSTEM
but if the vein does not collapse then we can suspect a DVT. - non compressibility
Why are duplex of the ____ veins not usually performed?
calf
b/c Many anatomical variations, so time consuming
Less accurate
Anticoagulation not routinely prescribed anyway
Clot often resolves spontaneously
20% will propagate to popliteal or femoral vein – serial evals every 3-5 days in patients who are still symptomatic
Llł
Limitations to Venous Duplex of LE’s?
Iliac and pelvic veins are difficult to evaluate
Obesity and severe edema limit exam
Saphenous vein (superficial) can be mistaken for the femoral vein (deep)
Patient may have collaterals - we can miss a DVT then cause the collateral circulation will a lot the vein to compress even if there is a DVT there
Vein may be compressed externally by node or tumor, not clot
Difficult to determine acute from chronic DVT
-Abnormalities may persist for 6 months
Venous duplex LE - CVI - leaky valves?
Common – 20% of American adults, esp women
Previous DVT is an important risk factor
CVI diagnosis tool?
Duplex US
What is used to map VV?
Duplex US
What is used to locate the level or venous reflux?
Dulex US
Duplex US also guides _____________ treatments
percutaneous
Venous duplex US for CVI is don’t with patient in what position?
standing
Also used as preoperative evaluation for autologous vein graft
CVI patho?
chronic venous engorgement - from valvular insufficiency or venous occlusion
