Pulmonary Disorders II

Eur Heart J. 2022;43:3618-3731)

Group 1 (PAH): Idiopathic, heritable, and drug/toxin-induced PAH, as well as PAH associated with

various diseases, PAH with features of venous/capillary (PVOD/PCH) involvement, or persistent

newborn PH

Group 2: PH caused by left heart disease

Group 3: PH caused by chronic lung disease and/or hypoxia

pulmonary artery obstructions

Group 5: PH with unclear multifactorial mechanisms

PH is defined as a mean pulmonary artery pressure (mPAP) greater than 20 mmHg at rest as measured

by right heart catheterization. PH is a term that encompasses all 5 groups and is not specific to any

single group. (Eur Respir J. 2024;64(4):2401324; Eur Heart J. 2022;43:3618-3731)

Hemodynamic definitions of PH (Eur Heart J 2022;43:3618-731; Eur Respir J. 2024;64(4):2401324)

Groups 1, 3, 4, and 5: Precapillary PH defined as mPAP greater than 20 mmHg, pulmonary

capillary wedge pressure (PCWP) less than or equal to 15 mm Hg, and PVR greater than 2

Wood units

ii.

Group 2: Isolated postcapillary PH defined as mPAP greater than 20 mmHg, PCWP greater

than 15 mm Hg, and PVR less than or equal to 2 Wood units

iii.

Group 2: Combined pre- and postcapillary PH defined as mPAP greater than 20 mmHg, PCWP

greater than 15 mm Hg, and PVR greater than 2 Wood units

Initial symptoms of group 1 (PAH) are nonspecific.

Common symptoms: Fatigue, shortness of breath with exertion, chest pain, and syncope

Less common presentations: Dry cough, nausea, and vomiting

of such symptoms. This list is not complete, and additional tests may be performed based on patient-

specific factors.

Electrocardiogram

BNP/N-terminal pro–brain natriuretic peptide (NT-proBNP)

Chest radiograph

ABG

Echocardiogram is used to predict likelihood of PH based on specific findings

Peak tricuspid regurgitation velocity (pTRV) is a key factor in suggesting the probability of

PH, but it is only a suggestive factor and should not be used independently to predict PH.

Guidelines differ in their recommendation for threshold of pTRV to suggest PH, with newer

guidelines using > 2.8 m/second.

ii.

Various measurements in the ventricles, pulmonary artery, inferior vena cava, and right atrium

contribute to the determination of PH diagnosis.

iii.

Echocardiogram should not be used independently to diagnose PH.

Ventilation/perfusion scan can be used to identify possible group 4 PH (CTEPH).

Computed tomography (CT) or CT pulmonary angiography (if CTEPH is suspected)

Cardiac magnetic resonance imaging can provide noninvasive prognostic assessment of the right

heart initially and at follow up.

Right heart catheterization is required to confirm diagnosis.