SACCM 22: Pulmonary Hypertension Flashcards

1
Q

What is the human mean pulmonary arterial pressure defining as pulmonary hypertension?

A

meanPAP > 25 mm Hg

cutoff fairly arbitrary, newer definition > 20 mm Hg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 categoris of pulmonary hypertension etiologies?

A
  • increased pulmonary blood flow (increased CO)
  • increased pulmonary vascular resistance
  • increased pulmonary venous pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is Precapillary pulmonary hypertension

A

increased pulmonary vascular resistance without increased pulmonary venous pressure

typically from pulmonary vascular disease, vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is postcapillary pulmonary hypertension?

A

increased pulmonary venous pressure from left-sided heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is reactive pulmonary hypertension?

A

postcapillary PH with secondary precapillary PH (from pulmonary arterial vasoconstriction and pulmonary vascular disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the characteristic changes to ventricles from pulmonary hypertension seen on echo?

A
  • RV hypertrophy
  • LV underfilling
  • flattened interventricular septum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Besides characteristic changes to ventricles, what other findings on echo support pulmonary hypertension?

A
  • pulmonary artery dilation and altered blood flow
  • caudal vena cava and RA enlargement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do you estimate systolic pulmonary arterial pressure?

A

With the modified Bernoulli equation calculate RA to RV pressure gradient –> the higher, the more PAP
Pressure gradient = 4 x velocity [m/s]2
* velocity here: measured peak tricuspid regurgitation velocity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

For the RA to RV pressure gradient to assess degree of pulmonary hypertension, how do you classify mild, moderate, and severe?

A
  • mild 30-50 mm Hg
  • moderate 50-75 mm Hg
  • severe > 75 mm Hg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What degree of tricuspid regurgitation velocity and echo changes gives you a high probability of pulmonary hypertension?

A
  • TRV higher than 3.4 m/s + 1 or more changes on echo
  • TRV 3.0 - 3.4 + 2 or more changes on echo
  • TRV < 3.0 or not measurable + 3 changes on echo
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 6 clinical groups of pulmonary hypertension according to the ACVIM consensus guidelines?

A
  1. Pulmonary arterial hypertension (PAH)
  2. Left-sided heart disease
  3. Respiratory diseae/ hypoxia
  4. Pulmonary thrombotic or thromboembolic disease
  5. Parasitic disease (HW or angiostrongyliasis)
  6. Multifactorial/unclear mechanism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the mechanism of action of sildenafil?

A

phosphodiesterase-5 inhibitor -> inhibits cGMP metabolism -> will cause accumulation of cGMP in pulmonary vascular smooth muscle cells
-> relaxation of smooth muscles and inhibition of hypertrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In what type of pulmonary hypertension is sildenafil contraindicated and why?

A

PH from left-sided heart disease
sildenafil will increase right-sided CO in these patients due to decreased afterload -> increased venous return to the LA -> increased PA, pulmonary venous and pulmonary capillary pressure -> iatrogenic pulmonary edema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly