What is PAH?

In patients with Pulmonary Arterial Hypertension (the most rare form
of PH)* characteristic changes occur within the pulmonary circulation, which include thickening of the linings and obstruction of the small pulmonary blood vessels. They are both structurally and functionally abnormal. In severe cases up to 80% of these very small blood vessels are rendered non-functional. As a result the pressure in the pulmonary circulation rises well above normal and this places strain on the right side of the heart. This strain can cause the heart to enlarge and the patient may develop heart failure. This is a disease that can affect all ages and is more commonly seen in females. Pulmonary Arterial Hypertension has an estimated prevalence of about 30-50 per million population.

* Class 1 WHO diagnostic classification

(a) Cross-section of normal
pulmonary artery

(b) Reduced opening of pulmo-
nary vessels due to cell
proliferation and remodelling
in advanced pulmonary

(c) Longitudinal section with
pathological changes within
the vessels (proliferation,
deposition of blood clots,
thickenig) causing difficul
ties for the heart to pump
blood through the lungs



The future for Pulmonary Arterial Hypertension

While a cure for this aggressive and life threatening disease is still some way off, there is much to be optimistic about. There are an ever increasing number of therapies available for the effective treatment
for Pulmonary Arterial Hypertension, which improve the quality and length of life. The aim for the present should be to ensure that all
patients with Pulmonary Arterial Hypertension have access to centres
of excellence in the diagnosis, management and ongoing treatment
of this disease.

Last updated: March 14, 2012