Pulmonary HTN

Question 1

Pre-capillary pulmonary HTN criteria

Answer 1

mPAP >20
PAWP </= 15
PVR >/= 3 Uood units

(Per the 6th World Symposium on Pulmonary HTN)

Question 2

Isolated post-capillary pulmonary HTN criteria

Answer 2

PAWP >15
mPAP >20
PVR <3 Wood units

(Per the 6th World Symposium on Pulmonary HTN)

Question 3

Combined pre- and post-capillary pulmonary HTN criteria

Answer 3

PAWP >15
mPAP >20
PVR >/= 3 Wood units

(Per the 6th World Symposium on Pulmonary HTN)

Question 4

Normal mean PAP

Answer 4

14 +/- 3.3 mmHg (~12-17)

• Since the 1st World Symposium on PH in 1973, PH was arbitrarily defined as mPAP >/= 25
• Recent data suggests that 14 +/- 3.3 is the normal mPAP
• mPAP >20 is 2 SD above the upper limit of normal and the new cutoff for pulmonary HTN.
• 6th WSPH Task Force added PVR to the definition to differentiate pre- and post-capillary PH.
• PVR cutoff used is >/= 3 Wood units.

Simonneau et. al. 2018

Question 5

WHO Group 1 PH

Answer 5

Pulmonary arterial HTN (PAH)

• Due to vascular remodeling of pulmonary arteries (idiopathic, medications, HIV, connective tissue disorders)
• Pre-capillary
• mPAP >20, PCWS </=15
• PVR >/= 3 WU

Question 6

WHO Group 2 PH

Answer 6

Pulmonary HTN due to left heart disease (Left heart failure, aortic valve disease, mitral valve disease)

• Post-capillary: mPAP >20, PCWP >15
• Isolated post-capillary: mPAP >20, PCWP >15, PVR <3 WU
• Combined pre- and post-capillary: mPAP >20, PCWP >15, PVR >/= 3 WU

Question 7

WHO Group 3 PH

Answer 7

Pulmonary HTN due to lung disease causing hypoxemia (COPD, ILD, sleep apnea)

• pre-capillary
• mPAP >20
• PCWP </= 15
• PVR >/= 3 WU

Question 8

WHO Group 4 PH

Answer 8

Chronic thromboembolic pulmonary HTN (CTEPH)

• pre-capillary
• mPAP >20
• PCWP </= 15
• PVR >/= 3 WU

Question 9

WHO Group 5 PH

Answer 9

Unclear and multifactorial

• can be precapillary, postcapillary, isolated postcapillary, or combined pre- and postcapillary
• Examples: sarcoidosis, chronic hemolytic anemia, thyroid disorders, sickle cell anemia, splenectomy, mediastinal tumors, chronic renal failure on HD

Question 10

Normal PVR in Woods units and Dynes/s/cm-5

Answer 10

Woods units: <2
Dynes/s/cm-5: 30-180

Question 11

Main concern with pulmonary vasodilators in left heart disease (WHO group 2)

Answer 11

Can worsen cardiogenic pulmonary edema due to increased preload to LV (from improved flow through pulmonary vascular bed). Caution when patients have elevated LAP and especially MR.

Pulmonary vasodilators are most useful in isolated RV failure