Pulmonary Hypertension

Our findings demonstrate that the addition of the dual endothelin receptor antagonist bosentan to prostanoid therapy significantly improves 6MWD as an indication of increased exercise tolerance and Tei index as an echocardiographic parameter summarizing RV function, in patients with progressive PAH and pulmonary hypertension due to chronic thromboembolic hypertension and due to interstitial lung disease. […]

The vessel wall becomes thinner and the lumen diameter increases. The external diameter, however, remains unchanged for several hours, during which time the endothelial cells that are orientated along the direction of blood flow at birth appear to become more elongated (Fig 1). These findings are compatible with the vessels having been stretched at birth, […]

State of the Art Immediately after birth, the pulmonary vasculature is remodeled rapidly to effect an abrupt reduction in pulmonary vascular resistance. Remodeling continues rapidly for the first 1-2 months, as the lung adapts to extrauterine life, and then more slowly as the vessels grow throughout childhood. Little is known about normal early postnatal development, […]

It seems likely that the major action of prostacyclin is the relaxation of this vasoconstriction which may cause, as a result, increased imbalance between ventilation and perfusion, as has been described for other vasodilators. The reason that a fall in arterial oxygen content does not occur is because prostacyclin raises CO and so increases the […]

Patients with a picture of predominant thrombotic lesions can give a history compatible with recurrent pulmonary infarction, can have evidence of proximal vessel occlusion on ventilation-perfusion scans or pulmonary angiography, and can have an identifiable source for their emboli; however, others with obstruction confined to the peripheral vessels give no such history, -and no source […]

Prostacyclin has its site of action on the resistance vessels of both the systemic and pulmonary circulations. It is not a venodilator and would not be expected to alter the preload of the right ventricle. Its fast onset of action and short half-life made prostacyclin an ideal drug for use in testing the response of […]

Seventeen of the 23 patients had a fall in PVR of at least 20 percent while receiving the incremental doses of prostacyclin. In one patient with peripheral thrombotic lesions and obstruction of proximal vessels, the prostacyclin was discontinued when the PVR rose 20 percent. In two patients where the predominant histologic findings were thrombotic lesions […]

Hemodynamic Measurements The effect of short-term administration of prostacyclin was assessed in each patient after obtaining written informed consent. No patient had taken an oral vasodilator in the 24 hours prior to the study. Right cardiac catheterization was undertaken after an eight-hour fast with the patient in a supine position, following insertion of a triple-lumen […]

In each case the eventual diagnosis fell into one of the following six separate categories: (1) Primary Pulmonary Hypertension Where the Predominant Findings Were of Plexogenic Lesions. Five female patients with a mean age (±SD) of 32 ±6 years were diagnosed after histologic examination of pulmonary tissue obtained from open lung biopsy in one, heart-lung […]

It has become widely accepted that the pathologic changes which occur in the pulmonary vessels in certain forms of pulmonary hypertension make some patients theoretically more amenable to treatment with vasodilators than others,*2 for instance, patients who have primary pulmonary hypertension where the dominant lesions are of a plexogenic pulmonary arte-riopathy are often given a […]