Author
Home > Science > What is the Difference Between PH and PAH?

Guilherme Mazui

•4 minutes to read

What is the Difference Between PH and PAH?

🆚 Go to Comparative Table 🆚

The main difference between pulmonary hypertension (PH) and pulmonary arterial hypertension (PAH) lies in their definitions and causes.

  • Pulmonary Hypertension (PH): This is a general term used to describe high blood pressure in the lungs from any cause. It encompasses a range of conditions that are grouped into five categories, including PAH. PH affects approximately 10% to 20% of the general population.
  • Pulmonary Arterial Hypertension (PAH): This is a specific subgroup of PH and is a chronic, currently incurable disease that causes the walls of the arteries of the lungs to tighten and stiffen. PAH is characterized by an elevated mean pulmonary artery pressure and can be idiopathic, heritable, or associated with other conditions such as connective tissue diseases, portal hypertension, congenital heart disease, or drug and toxin use. PAH is quite rare, with only 500 to 1,000 new cases diagnosed each year in the U.S..

In both PH and PAH, high blood pressure disrupts proper circulation of blood between the heart and lungs, causing the heart to overcompensate for the reduced heart-lung functionality. This extra work causes the right side of the heart to thicken and grow progressively weaker. The World Health Organization (WHO) has grouped PH into five categories, with PAH falling under WHO Group 1.

On this page
  • What is the Difference Between PH and PAH?
  • Comparative Table: PH vs PAH

    • Comparative Table: PH vs PAH

    Here is a table comparing the differences between Pulmonary Hypertension (PH) and Pulmonary Arterial Hypertension (PAH):

    Feature Pulmonary Hypertension (PH) Pulmonary Arterial Hypertension (PAH)
    Definition PH is a broad term that encompasses several types of pulmonary hypertension, including PAH PAH is a specific type of PH that is characterized by elevated pressures in the pulmonary vasculature, abnormal smooth muscle proliferation, and endothelial dysfunction
    Classification PH is classified into five groups, including PAH (Group 1), PH caused by left heart disease (Group 2), PH caused by lung diseases/hypoxia (Group 3), pulmonary artery obstructions (Group 4), and a miscellaneous group with unknown or multifactorial mechanisms (Group 5) PAH is the first group within the PH classification and is further classified into subgroups, such as idiopathic PAH, heritable PAH, drug- and toxin-induced PAH, and PAH associated with connective tissue diseases and HIV
    Causes The exact causes of PH are not fully understood, and it can be associated with various pulmonary and systemic diseases PAH is a rare, chronic, progressive condition caused by abnormal smooth muscle proliferation and endothelial dysfunction, leading to elevated pressures in the pulmonary vasculature
    Diagnosis PH diagnosis is challenging due to a well-documented time lag between symptom onset and diagnosis PAH diagnosis relies on right heart catheterization, which confirms the presence of a mean pulmonary arterial pressure (mPAP) >25 mm Hg at rest with pulmonary lung restriction or signs of chronic thromboembolism
    Treatment Treatment approaches for PH vary depending on the underlying cause and severity of the condition PAH treatment options also vary, and they are targeted to address the specific pathophysiological mechanisms of PAH
    Read more:

    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.