Echo, Fetal Echo and Advanced Imaging

Question 1

What makes echo axial resolution better

Answer 1

Higher transducer frequency

Question 2

What makes echo lateral resolution better

Answer 2

• Narrower ultrasound beam width
• Larger size probe, higher frequency and focusing

Question 3

What makes echo temporal resolution (frame rate) better

Answer 3

• Decreasing depth (less time for farthest wave to return)
• Narrowing sector
• Lower line density
• Single focal point
• Parallel beam forming

Question 4

Shortening fraction equation

Answer 4

%FS = (EDD-ESD) / EDD x 100

Question 5

Ejection fraction equation

Answer 5

%EF = (EDV-ESV) / EDV x 100

Question 6

Normal markers of diastolic function (E/A, E’, E/E’)

Answer 6

• E/A: 2
• E’ > 10
• E/E’ < 10

Question 7

Abnormal relaxation markers of diastolic function (E/A, E’, E/E’)

Answer 7

• E/A: < 1
• E’ < 10
• E/E’ < 10

Question 8

Pseudonormalization markers of diastolic function (E/A, E’, E/E’)

Answer 8

• E/A: 0.8-2
• E’ < 10
• E/E’ > 10

Question 9

Restrictive markers of diastolic function (E/A, E’, E/E’)

Answer 9

• E/A: >2
• E’ < 10
• E/E’ > 10 (usually really high)

Question 10

TEE absolute contraindications

Answer 10

• Unrepaired TEF
• Esophageal obstruction
• Poor airway control
• Uncooperative unsedated patient

Question 11

TEE relative contraindications

Answer 11

• Previous esophageal surgery with possible residual obstruction
• Esophageal varices
• Vascular ring or anomaly that could produce airway obstruction
• Severe coagulopathy
• Cervical spine injury or instability

Question 12

Stress echo indications

Answer 12

• Coronary artery disease: diagnosis/risk stratification
• Exertional dyspnea
• PH
• Mitral stenosis/insufficiency
• Aortic stenosis (LV dysfunction and low grade stenosis, use dobutamine)
• HOCM

Question 13

What does LGE on MRI show

Answer 13

• Myocardial infarction
• Fibrosis
• Myocarditis
• Endocardial fibroelastosis

Question 14

Reasons to use CT instead of MRI

Answer 14

• Contraindication to MRI (pacemaker, ICD)
• Metallic implants cause too much artifact on MRI to see structures of interest
• Sedation needed for MRI but not CT
• Critically ill or unstable patient (dissection, PE)
• Airway and lung tissue evaluation is primary
• Coronary artery stenosis

Question 15

Normal lung perfusion scan differential R to L

Answer 15

• Right 55%
• Left 45%

Question 16

Indications for lung perfusion scan

Answer 16

• PA stenosis
• Pulmonary vein stenosis

Question 17

Normal septal to free wall thickness in adolescent

Answer 17

• 1.1 (range 0.8 to 1.4)
• Increases in adult to average of 1.2