Pulmonary hypertension

Question 1

Definition of pulmonary hypertension

Answer 1

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)

Question 2

What are the normal values of mPAP?

Answer 2

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

Question 3

Significance of mPAP 21-24mmHg

Answer 3

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

Question 4

What is pulmonary vascular resistance?

Answer 4

PVR = (mPAP - mPCWP) / Cardiac output

PVR ULN ~2 Wood units (WU)

Question 5

What is pulmonary arterial wedge pressure (PAWP)?

Answer 5

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

Question 6

What are the symptoms of PH?

Answer 6

Right ventricular dysfunction symptoms

Question 7

What are the clinical signs and examination findings of PH?

Answer 7

Question 8

What are the ECG changes in PH?

Answer 8

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

Question 9

What are the abnormal CXR findings in PH?

Answer 9

Question 10

What are the normal haemodynamic values during right heart catheterisation?

Answer 10

Question 11

What is the function of vasoreactivity testing?

What groups of PH are recommended for vasoreactivity testing?

What are the medications used in vasoreactivity testing

Answer 11

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

Question 12

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

Answer 12

Question 13

Summary of findings for different classification groups of PH

Answer 13