11-27-2001, 01:29 PM
Pulmonary Hypertension is high blood pressure in the blood vessels of the lungs - it can cause damage to the blood vessels, lower the blood oxygen levels and can cause heart failure.
11-14-2003, 11:11 AM
From: The National Heart & Lung Institute
Pulmonary hypertension (PH) is a rare lung disorder occurring as a primary idiopathic disease or as a complication of a large number of respiratory and cardiac diseases. PH can occur with or without an identifiable cause.
When a person has PH, the blood pressure in the pulmonary artery rises far above normal levels. The pulmonary artery is the blood vessel carrying oxygen-poor blood from the right ventricle, one of the pumping chambers of the heart, to the lungs. In the lungs, the blood picks up oxygen and then flows to the left side of the heart, where it is pumped by the left ventricle to the rest of the body through the aorta.
Hypertension is the medical term for an abnormally high blood pressure. Normal mean pulmonary-artery pressure is approximately 14 mmHg at rest. In the PH patient, the mean blood pressure in the pulmonary artery is greater than 25 mmHg at rest and 30 mmHg during exercise. This abnormally high pressure (pulmonary hypertension) is associated with changes in the small blood vessels in the lungs, resulting in an increased resistance to blood flowing through the vessels.
This increased resistance, in turn, places a strain on the right ventricle, which now has to work harder than usual against the resistance to move adequate amounts of blood through the lungs.
Until recently there has been little to influence the inexorable downhill course of patients with severe pulmonary hypertension, either idiopathic or secondary to connective tissue disease such as SLE or scleroderma. Patients are advised to avoid heavy physical exertion, high altitude, pregnancy and surgery. Routine therapy generally includes diuretics, oral anticoagulants, a dihydropyridine calcium antagonist, chronic home oxygen therapy and possibly digoxin.