Pulmonary hypertension
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Pulmonary hypertension (PH or PHTN) is a condition of increased blood pressure in the arteries of the lungs. Symptoms include shortness of breath, fainting, tiredness, chest pain, swelling of the legs, and a fast heartbeat. The condition may make it difficult to exercise. Onset is typically gradual.
According to the definition at the 6th World Symposium of Pulmonary Hypertension in 2018, a patient is deemed to have pulmonary hypertension if the pulmonary mean arterial pressure is greater than 20mmHg at rest, revised down from a purely arbitrary 25mmHg, and pulmonary vascular resistance (PVR) greater than 3 Wood units.
The cause is often unknown. Risk factors include a family history, prior pulmonary embolism (blood clots in the lungs), HIV/AIDS, sickle cell disease, cocaine use, chronic obstructive pulmonary disease, sleep apnea, living at high altitudes, and problems with the mitral valve. The underlying mechanism typically involves inflammation and subsequent remodeling of the arteries in the lungs. Diagnosis involves first ruling out other potential causes. High cardiac output states, such as advanced liver disease or the presence of large arteriovenous fistulas, may lead to an elevated mean pulmonary artery pressure (mPAP) greater than 20 mm Hg despite a pulmonary vascular resistance (PVR) less than 2 Wood units, which does not necessarily indicate pulmonary vascular disease.
As of 2022 there was no cure for pulmonary hypertension, although research to find a cure is ongoing. Treatment depends on the type of disease. A number of supportive measures such as oxygen therapy, diuretics, and medications to inhibit blood clotting may be used. Medications specifically used to treat pulmonary hypertension include epoprostenol, treprostinil, iloprost, bosentan, ambrisentan, macitentan, and sildenafil, tadalafil, selexipag, riociguat. Lung transplantation may be an option in severe cases.
The frequency of occurrence is estimated at 1,000 new cases per year in the United States. Females are more often affected than males. Onset is typically between 20 and 60 years of age. Pulmonary hypertension was identified by Ernst von Romberg in 1891.
How this connects to MD Respiratory Medicine
Cardiovascular function couples electrical activation, muscle contraction, chamber filling and vascular resistance to tissue perfusion. Structural, rhythm or vascular disorders can change symptoms and measurements in different ways; evaluation integrates hemodynamics, anatomy, time course and objective evidence.
Text credit: Wikipedia contributors, “Pulmonary hypertension”, original article · authors & revision history · CC BY-SA 4.0. Unmodified opening extract, accessed 24 September 2026. This Wikipedia-derived section is provided under CC BY-SA 4.0; the independent MedAtlas notes and design are separate works.
Pulmonary hypertension · visual study map
Scalable vector illustration. Labeled conceptual map, not a precise anatomical, histological or diagnostic image.The wording in this learning map is adapted from the attributed Wikipedia background section below (CC BY-SA 4.0).
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