Guidelines for evaluating the severity of pulmonary hypertension establish a mild condition at 30 to 40 millimeters of mercury, according to Echocardiology.org. Normal pulmonary artery pressure ranges from 18 to 25 mmHg, while moderate is between 40 and 70 mmHg, and severe is over 70 mmHg.
Pulmonary hypertension is high blood pressure that affects the lungs and right side of the heart when the arteries and capillaries in the lungs have become blocked or destroyed, making it more difficult for blood to flow through the pulmonary system, states Mayo Clinic. The condition causes the heart to work harder, leading to a weaker heart muscle and eventual heart failure. While there are treatments to improve the quality of life and lessen symptoms, pulmonary hypertension is not curable.