Pulmonary hypertension Flashcards

1
Q

Definition of pulmonary hypertension

A

Nice 6th World Symposium on PH 2019
1. Mean pulmonary arterial pressure (mPAP) > 20mmHg at rest (with 20mmHg being ULN)
2. Emphasis on pulmonary arterial wedge pressure (PAWP) and pulmonary vascular resistance (PWR)

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

What are the normal values of mPAP?

A

Normal mPAP 14 +/- 3mmHg
(Upper limit normal 20mmHg)

mPAP increases with exercise:
At HR 100/min - 32mmHg
Maximal exercise - 37mmHg
Exercise in > 50 years old - 47mmHg

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

Significance of mPAP 21-24mmHg

A

Risk of mortality in patients with elevated PAP is incrementally noted with mPAP between 19 and 24 mmHg and not necessarily restricted to patients with mPAP 25 mmHg or more

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

What is pulmonary vascular resistance?

A

PVR = (mPAP - mPCWP) / Cardiac output

PVR ULN ~2 Wood units (WU)

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

What is pulmonary arterial wedge pressure (PAWP)?

A

Current consensus ULN 12mmHg
(But most therapeutic studies of PAH used PAWP 15mmHg as threshold)

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

What are the symptoms of PH?

A

Right ventricular dysfunction symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the clinical signs and examination findings of PH?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the ECG changes in PH?

A
  1. P pulmonale (P > 0.25mV in lead II)
  2. Right axis deviation
  3. RV hypertrophy (R/S >1, R>0.5 in V1; RV1 + SV5 >1)
  4. RBBB
  5. RV strain pattern (ST-depression or TWI in right precordial (V1-V4), inferior (II, III, AVF) leads)
  6. Prolonged QTc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the abnormal CXR findings in PH?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the normal haemodynamic values during right heart catheterisation?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of vasoreactivity testing?

What groups of PH are recommended for vasoreactivity testing?

What are the medications used in vasoreactivity testing

A

Vasoreactivity testing in PAH to identify acute vasoresponders as candidates for treatment with high dose calcium channel blockers

Vasoreactivity testing in group 1 PAH:
1. Idiopathic PAH (IPAH)
2. Heritable PAH (HPAH)
3. Drug-induced PAH (DPAH)

Medications used:
1. Inhaled nitric oxide (INO)
2. Inhaled iloprost
3. IV epoprostenol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Diagnostic algorithm of patients with unexplained dyspnoea and/or suspected pulmonary hypertension

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

Summary of findings for different classification groups of PH

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pathophysiology of PAH

A
  1. Right heart failure
    - RV remodelling
    - RV dysfunction
  2. Progressive pulmonary vasculopathy and obstruction
    - Intimal proliferation and fibrosis
    - Medial hypertrophy
    - Plexiform lesions
    - Vasoconstriction
    - Prone to thrombosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

WHO-FC of PAH
- Strongest predictors of survival
- Worsening classification most alarming indicators of disease progression

A

FC1 - PAH without limitation of physical activity, and activity does not cause symptoms
FC2 - PAH with slight limitation of physical activity. Comfortable at rest, normal activity causes undue symptoms
FC3 - PAH with marked limitation of physical activity. Comfortable at rest, less than normal activity causes undue symptoms
FC4 - PAH with inability to carry out any activity without symptoms, symptomatic even at rest.

Symptoms: dyspnoea, fatigue, chest pain, near syncope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

6MWT monitoring in PAH

A

Influenced by: sex, age, height, weight, comorbidities, need for oxygen, learning curve, motivation

Test results are usually given in absolute distance (metres) rather than the percentage of predicted values

Hyxpoxaemia may be associated with worse survival

Absolute threshold value:
- 1 year mortality: 165m
- 1 year survival: 440m

17
Q

Simplified 4-strata risk assessment tool for PAH - WHO-FC, 6MWT, NTpBNP

A
18
Q

Comprehensive risk assessment in pulmonary arterial hypertension (three-strata model)

A
19
Q

Specific therapies for PAH

A

Medical
1. Calcium channel antagonists (in favourable vasoreactivity testing - IPAH/HPAH/DPAH)
- Nifedipine, diltiazem, amlodipine

  1. Endothelin receptor antagonists
    - Ambrisentan, bosentan, macitentan
  2. Phosphodiesterase 5 inhibitors and GC stimulators (not to be combined together or with nitrate - profound hypotension)
    - Sildenafil, tadalafil
    - Riociguat
  3. Prostacyclin analogues and prostacyclin receptor agonists
    - Epoprostenol, iloprost, treprostinil, beraprost
    - Selexipag
  4. Inhaled imatinib
  5. Activin/BMP pathway inhibitor
    - Sotatercept

Surgical
1. Balloon atrial septostomy and Potts shunt
- connects left PA and descending aorta to decompress right heart and increase systemic blood flow
- High risk and mortality

  1. Pulmonary artery denervation (PADN)
    - Theory: increased sympathetic overdrive leading to vasoconstriction and remodelling via baroreflex mediated stretch receptors at bifurcation of PAs
    - RFA denervation of said receptors improves haemodynamics
  2. Intensive care and ECMO (LVAD not yet available)
  3. Lung and heart transplantation
20
Q

Calcium channel antagonists in PAH

A
  • Side effects: hypotension, peripheral oedema