ICL 3.2: Pulmonary Hypertension

Question 1

what is group 1 HTN?

Answer 1

pulmonary arterial hypertension

can be hereditary or acquired

the LEAST common

ex. scleroderma

Question 2

what is group 2 HTN?

Answer 2

PH-LHD = left heart failure!

can be because of preserved EF, decreased EF, or congenital heart disease

14% of pulmonary HTN cases but for USMLE this is the most common cause of pulmonary hypertension

Question 3

what is group 3 HTN?

Answer 3

chronic hypoxia; cor pulmonale

caused by OSA or COPD

85% of pulmonary HTN cases

Question 4

what is group 4 HTN?

Answer 4

CTEPH = chronic thromboembolism pulmonary hypertension

presence of multiple chronic or organized occlusive thrombi or emboli still present in the elastic pulmonary arteries - main, lobar, segmental or sub-segmental - after at least three months of effective anti-coagulation

PAH-like arteriole muscularization

.14% of pulmonary HTN is caused by this

Question 5

what is group 5 HTN?

Answer 5

caused by sarcoidosis

.14% of pulmonary HTN is caused by this

Question 6

which groups are the 2 main causes of pulmonary HTN?

Answer 6

1. group 2 = left heart disease, HFpEF, HFrEF, valvular disease –> most common
2. group 3 = hypoxemic lung disease, obstructive lung disease, restrictive lung disease, OSA

Question 7

what are the causes of group 1 pulmonary HTN?

Answer 7

pulmonary arterial hypertension

1. idiopathic
2. heritable
3. drug and toxin induced

associated with connective tissue disease (scleroderma), HIV, portal hypertension, congenital heart disease, schistosomiasis

Question 8

what are the causes of group 2 pulmonary HTN?

Answer 8

pulmonary hypertension due to left-sided heart disease

1. left ventricular-systolic dysfunction
2. left ventricular diastolic dysfunction
3. valvular heart disease
4. specific congenital abnormalities

Question 9

what are the causes of group 3 pulmonary HTN?

Answer 9

pulmonary hypertension due to lung disease or hypoxia

1. COPD
2. interstitial lung disease
3. mixed restrictive or obstructive lung disease
4. alveolar hypoventilation disorders
5. chronic exposure to high altitude
6. developmental lung diseases

Question 10

what are the causes of group 4 pulmonary HTN?

Answer 10

chronic thromboembolic pulmonary hypertension and other pulmonary artery obstructions

1. chronic thromboembolic pulmonary hypertension
2. angiosarcoma
3. intravascular tumors
4. arteritis
5. congenital stenoses
6. parasites

Question 11

what are the causes of group 5 pulmonary HTN?

Answer 11

pulmonary hypertension with multifactorial mechanisms

11. hematological disorders (sickle cell)
12. systemic disorders ( sarcoidosis, Langerhans cell granulomatosis)
13. metabolic disorders (Gaucher’s disease)
14. renal disease

Question 12

what is pulmonary hypertension?

Answer 12

the MEAN pulmonary artery pressure is 25+ mmHg

you need both the systolic and diastolic pressure to calculate this

Question 13

what is the pulmonary artery pressure with group 2 pulmonary HTN?

Answer 13

mPAP > 25 mmHg

PCWP > 15 mmHg = post-capillary hypertension

this is PH due to left heart disease

this is the only type of PH with increased PCWP

Question 14

what is the pulmonary artery pressure with group 1,3,4,5 pulmonary HTN?

Answer 14

mPAP > 25 mmHg

PCWP < 15 mmHg = pre-capillary pulmonary hypertension

Question 15

how do you figure out what group of PH a patient has?

Answer 15

first use non-invasive echocardiogram to diagnose + clinical signs –> can tell you if it’s groups 2 or 3

then to asses for group 4 CTEPH, use non-invasive V/Q scan to diagnose

finally, to asses for groups 1 and 5, you need an invasive right heart catheterization and pulmonary angiogram to diagnose

Question 16

the two most common WHO groups of pulmonary hypertension account for what fraction of pulmonary hypertension?

Answer 16

99.6%

groups 2 and 3

Question 17

what are the symptoms of pulmonary hypertension?

Answer 17

1. dyspnea on exertion is the most common (make them go on a 6 minute walk)
2. fatigue
3. chest pain/discomfort
4. leg swelling
5. syncope
6. dizziness
7. cough is less common

Question 18

what do you see when you’re doing a PE of pulmonary hypertension?

Answer 18

1. lungs are clear – you’re compensating with CHF so there won’t be rales because the extra fluid is backing up in the legs, ascites, etc.
2. cor pulmonale signs = hepatomegaly, ascites, JV, leg edema
3. evidence of connective tissue disease if group 1

Question 19

what are the methods you can use to asses for pulmonary hypertension?

Answer 19

1. non-invasive chest CT with contract dye
2. non-invasive: echocardiogram with doppler
3. invasive right heart/pulmonary artery catheter

Question 20

what do you use a chest CT to asses for with pulmonary HTN?

Answer 20

1. assess LV/RV volumes
   RV/LV > 1.2 abnormal
2. assess PA diameter

PA/Aorta normally is 0.9 so > 1 abnormal

PA diameter
Men: up to 29 mm
Women up to 27 mm

Question 21

what do you use a echocardiogram with doppler to asses for with pulmonary HTN?

Answer 21

good screening tool but NOT diagnostic; you need to do right heart catheter to confirm pulmonary HTN on its own

1. assess LV/RV volumes
2. measure PA systolic pressure
3. LVEF
4. RV wall thickness
5. elevated tricuspid regurgitation jet

NO measures to calculate pulmonary vascular resistance (PVR)

Question 22

what do you use a right heart/pulmonary artery catheter to asses for with pulmonary HTN?

Answer 22

this is the accepted meta to diagnose pulmonary hypertension!

1. PA mean pressure (systolic/diastolic and pressures)
2. PCWP measurement
3. cardiac output measurement by thermodilution
4. transpulmonary gradient (TPG) as mean PAP-PCWP, and PVR as TPG/Cardiac output
5. pulmonary vascular resistance (PVR), and Cardiac output/index
6. pulmonary vasoreactivity: only for IPAH, HPAP, or DT PAH

Question 23

which of the below parameters measured by echocardiogram is a measure of pulmonary hypertension?

A. LV/RV volumes

B. tricuspid valve regurgitant jet

C. left ventricular ejection fraction

D. RV wall thickness

Answer 23

B. tricuspid valve regurgitant jet

the others are supportive but the tricuspid valve regurgitant tells you the severity of the pulmonary HTN

Question 24

how do you treat group 3 HTN?

Answer 24

treat the underlying disease!!

whether that be COPD, pulmonary fibrosis, interstitial lung disease or sleep disordered breathing

Question 25

why do we treat people with COPD with oxygen?

Answer 25

COPD patients with *resting* hypoxia, giving oxygen reduces mortality by: 1. reduces hypoxic vasoconstriction and therefore reduces pulmonary HTN 2. reduces polycythemia (polycythemia causes increased resistance due to blood thickening)

Question 26

how severe is the pulmonary HTN associated with sleep disordered breathing?

Answer 26

with OSA alone, you will have mild PH typically with OSA and OHS, severe pulmonary HTN may be observed nocturnal hypoxia has its own risk factors

Question 27

how does chronic exposure to high altitudes cause pulmonary HTN?

Answer 27

altitude decreases the inspired PO2 because of a decrease in barometric pressure mild pulmonary HTN occurs at rest and may increase substantially with exercise severe pulmonary HTN may occur with high altitude pulmonary edema, subacute mountain sickness and chronic mountain sickness

Question 28

how do you treat pulmonary HTN from chronic exposure to high altitudes?

Answer 28

this is NOT immediately reversed by breathing in oxygen because it's chronic descent from high altitude is primary treatment can also give alpha adrenergic blockade, salmeterol B agonist or CPAP

Question 29

how do you manage group 4 pulmonary HTN?

Answer 29

1. echo shows signs of TV dysfunction then give anticoagulation to try and breakdown clots 2. do V/Q scan to see if there's defects which would suggest CTEPH 3. do right heart catheterization to confirm pulmonary HTN to diagnose CTEPH 4. lifelong anticoagulation to prevent further clots from developing 5. assess for surgery to see if you can remove the clots if you can't operate, give phosphodiesterase

Question 30

how do you treat someone with CTEPH?

Answer 30

if someone with CTEPH isn't a candidate for surgery, give soluble guanylate cyclase stimulators = riociguat this is only give to patients who are deemed not to be good candidates for embolectomy or balloon pulmonary angioplasty (BPA) or for patients with residual pulmonary hypertension after embolectomy/BPA.

Question 31

what are some of the genes associated with group 1 pulmonary HTN?

Answer 31

1. IPAH and HPAH BMPR2* is AD; F > M other mutations include ALK-1, KCNK3, endoglin, SMAD9, cave-in-1 2. hereditary hemorrhagic telangiectasia (HTT) and PAH Alk-1 mutation 3. group 1 heritable PVOD/PCH EIF2AK4 mutation

Question 32

what do you do for a group 1 pulmonary HTN workup?

Answer 32

you find pulmonary HTN that's confirmed by the right heart cath so now you do acute vasoreactivity testing for groups 1 and 5 pulmonary HTN give NO or IV epoprostenol and if you see reactivity, treat with oral CCB and continue with that if it keeps working --> a positive test is if the mPAP decreases by at least 10 mmHg to below 40 mmHg after vasodilator is given if they don't respond to CCB then you can give the following to WHO group 1, but no other WHO group: 1. prostanoids 2. endothelial receptor antagonists (ERAs) 3. phosphodiesterase-5 inhibitors

Question 33

vasoreactivity test response to medical therapy should be tested in which WHO groups?

Answer 33

groups 1 and 5 do NOT test in people with HF

Question 34

what medication can you give to WHO group 4?

Answer 34

soluble guanylate cyclase stimulator Adempas = riociguat

Question 35

what are the class I-IV functional classifications of pulmonary HTN?

Answer 35

class I: ordinary physical activity does not cause undue dyspnea, fatigue, chest pain or near syncope class II: comfortable at rest, ordinary physical activity causes undue dyspnea, fatigue, chest pain or near syncope class III: marked limitation of physical activity. comfortable at rest. less than ordinary activity causes undue dyspnea, fatigue, chest pain or near syncope class IV: unable to perform any physical activity without symptoms. patients manifest signs of right heart failure. dyspnea and/or fatigue may be present at rest. discomfort is increased with any physical activity