High Yield PTEexam review part 42-43 Flashcards
Rank the VSD in terms of incidence from most common to least common (All 4)
- Membranous VSD - 70%
- Muscular (Trabecular) - 20%
- Inlet - 5%
- Outlet (Subpulmonic) 5%
What is the difference between piezoelectric effect* and *reverse piezoelectric effect?
piezoelectric = Conversion of sound to electrical signal
Reverse piezoelectric = Conversion of electrical signal to sound
What does the matching layer do to the energy of sound?
Increases efficiency of sound energy transfer into the body
What does the backing material layer function to do?
- Reduces ringing
- Shortens spatial pulse length
- Improves spatial resolution
- Decreases Q factor
What specific substance is found in the piezoelectric crystal?
Lead Zirconate Titanate
What is the formula for Q factor?
Resonant Frequency / Bandwidth
How would you calculate a right sided dP/dT?
Measure at 1 and 2 m/s on TR jet
Equation = (12 mmHg / time)
What is an abnormal RV dP/dT?
< 400 mmHg/sec = Abnormal
How would you calculate a myocardial performance index for the Right heart?
What is abnormal?
TG RV inflow / outflow
Abnormal = <0.4 via PWD
Abnormal = <0.55 in TDI
What is abnormal RV FAC?
What view is obtained here?
<35%
ME RV focused 4 chamber
What is abnormal RVEF by cardiac MRI?
<45%
What is Abnormal Tissue Doppler peak lateral tricuspid annulus systolic velocity (sā) of the RV?
< 10 cm/sec
What is abnormal RV free wall 2D strain?
A value more positive than -20 is abnormal
What value for RV isovolumetric acceleration is abnormal?
< 2.2 m/s2