Pulmonary Arterial Hypertension

Question 1

Normal right ventricle pressure

Answer 1

<25

Question 2

Normal PA pressure

Answer 2

14

Question 3

Equation for pulmonary artery pressure

Answer 3

P = CO*Pulmonary vascular resistance + PLA

Question 4

Resistance/compliance of pulmonary vascular system

Answer 4

Less muscle and elastin than in systmeic vessels, so low resistance, high compliance. Capillary recruitment helps

Question 5

Pressure definition of pulmonary hypertension

Answer 5

mean PA>25mmhg

Question 6

5 WHO groups

Answer 6

1: Pulmonary arterial hypertension (BMPR or associated with CTD HIV congential heart disease)
2: Left heart disease
3: Lung disease causing hypoxia (COPD/ILD)
4: thromboembolic
5: misc

Question 7

Vascular pathology of PAH

Answer 7

Plexiform lesions, in situ thombosis, medial hypertrophy

Question 8

BMPR2

Answer 8

Mutation can lead to PAH

Question 9

Other things that can cause PAH

Answer 9

CTD’S, Congenital heart diseases

Question 10

Idiopathic pulmonary arterial hypertension mortality?

Answer 10

Can live for 2.8 years

Question 11

Is RV like a weak LV?

Answer 11

No, morphologically different and embryologically different. RV is more compliant.

Question 12

Will RV fail when exposed to increased afterload?

Answer 12

Yes super easily.

Question 13

Why do pHTN patients decompensate so rapidly.

Answer 13

Vicious cycle. You can intuit this. Cardiogenic shock occurs eventually

Question 14

Symptoms of phtn

Answer 14

dyspnea fatigue chest pain, palpitations. all due to low perfusion. Then also ascites and peripheral edema

Question 15

Physical exam

Answer 15

RV heave, split S2, loud P2, TR due to left ventricular dilitation

Question 16

Are there rales in PAH?

Answer 16

No! Occurs before capillaries so no transudate.

Question 17

Right heart cath to diagnose must show

Answer 17

PCWP<15 for who I, III, IV.

Question 18

Natural history of PHTN

Answer 18

CO drops, PAP and RAP increase, PVR increases too

Final stage pulmonary artery pressure decreases dramatically due to right heart not being able to pump into it anymore.

Question 19

How to decrease RV afterload

Answer 19

Give CCBs, prostacyclin derivatives, No derivatives, PDE inhibitors. Endothelin receptor antagonists

Question 20

Use of CCBs in pulmonary HTN

Answer 20

Use dihydropyridines. Cause PA vasodilation but only if positive vasoreactivity test

Question 21

Vasoreactivity test

Answer 21

Give short acting vasodilator. If mPAP decreases by more than 10, then CCbs will work. Not many people are vasoresponders

Question 22

Prostanoids

Answer 22

Prostaglandin derivates that cause increase in cAMP.

Question 23

Three examples of prostanoids

Answer 23

Epoprostanol, treprostinil, iloprost

Question 24

Epoprostanol

Answer 24

Is prostacyclin, given by 2 dedicated IVs just incase one fails. Only pulmonary HTN medication with proven survival benefit.

Question 25

Endothelin receptor antagonists

Answer 25

Want a drug that blocks A but not B because B is implicated in endothelin clearance. Drugs include bosentan, abrisentan, macitentan.

Question 26

PDE5 inhibitors

Answer 26

Increase cGMP by preventing its breakdown. Sildenafil,

Question 27

Riociguat

Answer 27

Stimulator of GC, increases cGMP

Question 28

Problem with PA vasodilators

Answer 28

Decrease SVR and can cause hypotension, also abrupt withdrawal can cause PA hypertension!
Biggest problem, can worsten V/Q matching because will dilate the vessels around shitty alveoli.They also can increase pulmonary capillary pressure causing pulmonary edema

Question 29

Why do PA vasodilators worsten VQ matching

Answer 29

Because they dilate the vessels around shitty alveoli