LYCOS RETRIEVER 
Primary Pulmonary Hypertension: Blood
built 657 days ago
Primary pulmonary hypertension (PPH) is a serious and potentially life threatening cardiovascular condition that is not curable. A study published in the New England Journal of Medicine in August 1996 found that the use of fen phen for three months or longer is associated with a twenty-three fold increase in the risk of developing primary pulmonary hypertension. PPH causes high blood pressure in the lungs that leads to a feeling of constant breathlessness with minimal exertion, fatigue, dizzy spells, fainting, and chest pain. There is no known cause of PPH but it has been the direct result of the use of the once popular diet drug fen phen, or fenfluramine and phentermine combination.
Source:
Primary pulmonary hypertension is treated with drugs that cause widening of blood vessels (vasodilators) and lessen blood pressure. In most cases, calcium channel blockers (e,g, nifedipine and diltiazem) are used to treat primary pulmonary hypertension as vasodilators. Other vasodilator drugs have been used including phentolamine, phenoxybenzamine and prazosin. The effectiveness of vasodilator therapy varies from case to case.
Source:
Primary pulmonary hypertension may be due to genetic or unknown factors. Researchers believe the blood vessels are particularly sensitive to certain internal or external factors, and constrict, or narrow, when exposed to these factors, such as an immune system factor, or sensitivity to drugs or other chemicals.
Source:
Abstract—Primary pulmonary hypertension (PPH) is a syndrome of dyspnea, chest pain, and syncope defined by increased pulmonary vascular resistance and the absence of a known cause. It ... occurs in a familial form, which is linked to unidentified genes on chromosome 2. This syndrome is characterized by abnormalities of pulmonary vascular biology in each compartment of the blood vessel. The lumen has a prothrombotic diathesis, the endothelium displays an excessive production of vasoconstrictors relative to vasodilators, and the smooth muscle cells are depolarized and calcium-overloaded, which is due in part to reduced expression of voltage-gated potassium channels (Kv). This causes vasoconstriction and may promote cell proliferation. The adventitia displays excessive remodeling, which is associated with exaggerated metalloproteinase and elastase activity.
Source:
Pulmonary hypertension can be related to excessive pulmonary blood flow, such as occurs in congenital cardiac anomalies involving left to right shunts. When pulmonary blood flow is markedly increased and pulmonary vascular capacity is reached, any further increase in blood flow causes a rise in pressure.
Source:
Pulmonary hypertension: High blood pressure in the [P]ulmonary artery that conveys blood from the right ventricle to the lungs. The pressure in the pulmonary artery is normally low compared to that in the aorta.
Source:
MORE ABOUT
Blood