pHTN and PVS Flashcards
2D pHTN findings
1) Diminished or absent “a” wave of the pulmonary valve
2) Midsystolic closure of the pulmonary valve
3) Enlarged chambers of the right heart
4) D-shaped LV cavity
Transtricuspid pressure gradient
4(TRV)^2
What does tricuspid regurgitation velocity reflect?
The pressure difference during systole between the RV and the RA.
PASP
PA systolic pressure
In the absence of a gradient across the pulmonic valve or RVOT, RVSP is equal to PASP
When might the TRV appear low?
In the presence of markedly increased RA pressure due to RV infarct, RV failure, or severe TR.
RVSP
RA pressure + peak TR velocity
RA + 4(V)^2
How should TR velocity be measured?
Held-expiration, to avoid respiratory variation
PAEDP
4(PREDV)^2 + RAP
MPAP
4(Peak PRV)^2
or
1/3(PASP) + 2/3(PAEDP)
or
79 - 0.45(AcT) (For RVOT flow velocity)
Why is there a dip in the PA-RV pressure gradient?
PRV usually reflects small pressure differences between the PA and the RV, ATRIAL CONTRACTION with increased RV pressure creates a unique DIP in the velocity curve.
NB: When PA pressure is high, RA contraction usually does not make a notable change in the PA-RV pressure gradient. NO DIP!
Mahan’s equation for MPAP
MPAP = 79 - 0.45(AcT) (For RVOT flow velocity)
* Dependent on CO and HR, adjust for 100bpm.
Acceleration time
The time interval between the beginning of the flow and its peak velocity
PVR (Cath Lab)
(MPAP - PCWP)/CO
PVR (Doppler)
10 (TRV/RVOT TVI) + 0.16
- A cutoff value of 0.2 for TRV/RVOT TVI separates a group with PVR greater than 2 Wood units
How can you assume pHTN is due to a pulmonary process?
If mitral inflow shows a nonrestrictive diastolic filling pattern.
What happens to hepatic venous flow in pHTN?
There is prominent atrial flow reversal in the hepatic vein caused by increased diastolic pressure and decreased compliance of the RV.
***There is very little respiratory variation of atrial flow reversal in pHTN, unlike the variation seen in restrictive CM or constrictive pericarditis.
How to quantify RV dysfunction?
1) RV dilation
2) Paradoxical septal motion
3) TRV > 2.8m/s
Congenital pulmonary veins
From one to all four PVs can be connected with or drain into the right side of the heart.
Best seen with the suprasternal short-axis view
One of the PVs may drain into the VERTICAL VEIN, which connects with the innominate vein.
PV Stenosis: Etiology and Rx
May be congenital or due to PVI (catheter ablation)
The best treatment is percutaneous dilatation or stent placement.
Causes of increased RV pressure
1) RV infarct
2) pHTN
3) Constrictive pericarditis
