Pulm HTN

Question 1

Normal pulm artery pressure vs. HTN

Answer 1

Normal: 10-14 mmHg
HTN: >25 mmHg or >35 mmHg during exercise

Question 2

Consequent of pulm HTN

Answer 2

Arteriosclerosis,
medial hypertrophy
intimal fibrosis of pulm arteries.

Question 3

Primary pulm HTN

Answer 3

Inactivation mutation in BMPR2 gene;
normally function to inhibit vascular SM proliferation;
Poor prognosis

Question 4

Secondary pulm HTN

Answer 4

1) COPD (destruction of lung parenchyma)
2) Mitral stenosis: increased resistance and pressure
3) Recurrent thromboemboli
4) autoimmune (SLE,- intimal fibrosis, -medial hypertrophy)
5) L to R shunt (increase in shear stress, endothelial injury)
6) sleep apnea or living at high altitude

Question 5

Pulm HTN course:

Answer 5

Severe respiratory distress
cyanosis and RVH
Death from compensated cor pulmonale

Question 6

Pulm vascular resistance

Answer 6

PVR = (P pulm artery - P L atrium)/Cardiac output

P pulm artery = pressure in pulm artery
P L atrium = pulm wedge pressure

Question 7

Things to remember about PVR calculation

Answer 7

dP= QxR, so R= dP/Q
R= 8nl/(pi*r^4)

n= viscosity of blood
l= vessel length
r= vessel radius