Pulmonary arterial hypertension vs Secondary pulmonary hypertension groups
How to tell Pulmonary arterial hypertension and Secondary pulmonary hypertension groups apart when a board question makes them look alike.
Group 1 is pulmonary arterial vascular disease; Groups 2-5 are classified by the upstream cause.
Side by side
Group 1 pulmonary arterial hypertension: idiopathic, heritable such as BMPR2, drug-induced, or associated PAH without left-heart, lung/hypoxia, or thromboembolic cause.
Groups 2-5 are secondary patterns: left heart disease, lung disease/hypoxia, chronic thromboembolic obstruction, or unclear/multifactorial mechanisms.
Small pulmonary arterial remodeling raises pulmonary vascular resistance in a precapillary PAH pattern.
Pulmonary pressures rise from pulmonary venous backup, hypoxic vasoconstriction, chronic obstruction, or mixed systemic mechanisms.
Group 1 PAH: pulmonary vascular disease with normal left-sided filling pressure. Right heart catheterization shows mean pulmonary artery pressure at or above 20 mmHg with pulmonary capillary wedge pressure at or below 15 mmHg and pulmonary vascular resistance above 2 Wood units. Risk factors: BMPR2 mutation (heritable PAH), connective tissue disease (scleroderma), HIV, portopulmonary hypertension, drug-induced (anorexigens, methamphetamine), congenital heart disease.
Groups 2 to 5 secondary pulmonary hypertension: Group 2 is left heart disease (HFpEF, HFrEF, valve disease; elevated PCWP); Group 3 is lung disease and hypoxia (COPD, ILD, sleep-disordered breathing); Group 4 is chronic thromboembolic pulmonary hypertension (CTEPH, treatable with pulmonary endarterectomy or balloon angioplasty); Group 5 is unclear or multifactorial (sarcoidosis, sickle cell disease, end-stage renal disease).
The trap
Do not call every pulmonary hypertension “PAH”; PAH is Group 1, while most secondary causes live in Groups 2-5.
Watch it explained
The repair move
For pulmonary hypertension groups, name the cause before naming the group: artery, left heart, lung/hypoxia, clot, or multifactorial.
Try a free question
CoreA patient has pulmonary arterial hypertension with no left heart or lung disease, and genetic testing shows a BMPR2 mutation. Which pulmonary hypertension group is most likely?
Show answer and explanation
Answer: A. Group 1: pulmonary arterial hypertension. Group 1 is pulmonary arterial hypertension, including idiopathic, heritable, drug-induced, and associated PAH.
Why the other choices are tempting
- B. Group 2 is due to left-sided heart disease.
- C. Group 3 is due to chronic lung disease or hypoxia.
- D. Group 4 is due to chronic pulmonary artery obstruction, classically chronic thromboembolic PH.
- E. Group 5 is unclear or multifactorial PH.
Flashcards
Tap a card to flip it.
What is the fastest separator for Pulmonary arterial hypertension vs Secondary pulmonary hypertension groups?
Group 1 is pulmonary arterial vascular disease; Groups 2-5 are classified by the upstream cause.
What clue should make you choose Pulmonary arterial hypertension?
Group 1 pulmonary arterial hypertension: idiopathic, heritable such as BMPR2, drug-induced, or associated PAH without left-heart, lung/hypoxia, or thromboembolic cause.
Quick answers
What is the fastest way to tell Pulmonary arterial hypertension from Secondary pulmonary hypertension groups?
Group 1 is pulmonary arterial vascular disease; Groups 2-5 are classified by the upstream cause.
What is the key clue for Pulmonary arterial hypertension?
Group 1 pulmonary arterial hypertension: idiopathic, heritable such as BMPR2, drug-induced, or associated PAH without left-heart, lung/hypoxia, or thromboembolic cause.
What is the key clue for Secondary pulmonary hypertension groups?
Groups 2-5 are secondary patterns: left heart disease, lung disease/hypoxia, chronic thromboembolic obstruction, or unclear/multifactorial mechanisms.
What is the common trap with Pulmonary arterial hypertension vs Secondary pulmonary hypertension groups?
Do not call every pulmonary hypertension “PAH”; PAH is Group 1, while most secondary causes live in Groups 2-5.