Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0042373 (vascular disease)
 17,070 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Reduction of pulmonary vascular resistance by a high inspired oxygen concentration is a common, but not universal phenomenon in patients with pulmonary vascular disease of varying etiology that may determine their response to long-term domiciliary oxygen therapy. We therefore determined changes in PVR during oxygen therapy in two patient populations not previously studied: systemic sclerosis (n = 8, mean age +/- SEM, 44.5 +/- 5.4 years) and primary pulmonary hypertension (n = 7, mean age +/- SEM 38 +/- 7.8 years). All patients were hypoxemic (arterial oxygen tension, on air 9.5 +/- 1.2 kPa for SSc and 8.3 +/- 0.6 kPa for PPH, p greater than 0.05). Right atrial pressure, pulmonary artery pressure, pulmonary artery occlusion pressure, systemic arterial pressure, PaO2 and cardiac output by thermodilution were measured at three, 20-min intervals while inspiring air and again after inspiring 60 percent oxygen for 30 min. The PVR fell significantly with oxygen in patients with SSc from 797.6 +/- 179.2 to 610 +/- 151.6 dynes/s/cm-5 (p less than 0.01), and this fall correlated with baseline PAP and PaO2 prior to oxygen therapy (r = 0.86, p less than 0.025; r = 0.77, p less than 0.05, respectively). In patients with PPH, there was no significant fall in PVR with oxygen (from 969 +/- 80.2 to 851.9 +/- 91.2 dynes/s/cm-5, p greater than 0.05) and no predictor of a vasodilator response in individual patients. In SSc, hypoxic pulmonary vasoconstriction contributes more consistently to elevated PVR than in patients with PPH.
 ...
PMID:Hypoxic pulmonary vasoconstriction in systemic sclerosis and primary pulmonary hypertension. 189 17

A group of Wistar albino rats was injected subcutaneously with monocrotaline to induce vasoconstrictive hypertensive pulmonary vascular disease characterized by medial hypertrophy of small pulmonary arteries, the appearance of muscular pulmonary arterial vessels of arteriolar dimensions (less than 20 microns) in diameter), and exudative changes in the lung parenchyma. The vascular abnormalities were quantified by measuring the percentage medial thickness of small pulmonary arteries, the number of muscular pulmonary arterial vessels below 20 microns in diameter per cm2 of lung section and by determining the smallest arterial vessels in each case showing muscularity. A second group of rats was born in a decompression chamber and kept in hypobaric hypoxia for a month of the neonatal period, developing hypoxic hypertensive pulmonary vascular disease as a consequence. The animals in this group were allowed to recover in room air for a period of 3 months and were then injected with the same dose of monocrotaline as that given to the first group. The rats previously exposed to hypoxia exhibited an exaggerated response to the alkaloid, showing in particular many more small muscular pulmonary arterial vessels which were of a smaller diameter than those found in the eupoxic rats treated with the alkaloid. The experiment demonstrates the perinatal hypoxia exaggerates the effects of agents inducing vasoconstrictive pulmonary hypertension with a shift of the segment of the pulmonary arterial tree involved to the periphery as in hypoxia. Reports of a similar phenomenon are noted as occurring in babies born at high altitude, spending their infancy there and subsequently developing primary pulmonary hypertension later in life.
 ...
PMID:Influence of hypobaric hypoxia in infancy on the subsequent development of vasoconstrictive pulmonary vascular disease in the Wistar albino rat. 190 9

Heart-lung transplantation (HLT) and lung transplantation (LT) are effective treatment modalities for patients with advanced pulmonary parenchymal or vascular disease. Lung transplantation offers potential advantages over HLT, including reduced pretransplant waiting time and improved efficiency of organ utilization, and is currently being offered to patients formerly treated by HLT. To explore the relative merits of these procedures, the authors examined the results in 44 procedures (23 HLT and 21 LT) in 42 patients transplanted at their institution. Heart-lung transplant recipients included 20 adults and three children (ages 5,5 and 3). Most HLT patients had primary pulmonary hypertension (PPH) (n = 9) or Eisenmenger's syndrome (ES) (n = 8). Twenty-two of twenty-three patients have been long-term survivors (mean follow-up = 17.8 months, Kapaln-Meier survival at 12 months = 85%). Obliterative bronchiolitis (OB) has occurred in five patients (22%), and all have died. Of 21 LTs in 19 patients, nine had obstructive and eight had restrictive lung diseases. Three single-LT (SLT) patients had PPH, and one had ES secondary to a ventricular septal defect. Mean pulmonary artery pressures fell from 55 +/- 6 mm Hg before SLT to 21 +/- 3 mm Hg after SLT; p less than 0.001. Three pediatric patients (ages 4, 10, 17, and 17[re-transplant]) have undergone four SLTs. With mean follow-up of 6.4 months, LT patients have survival at 12 months of 80% (Kaplan-Meier). Lung transplant patients wait a far shorter time for their transplant than do HLT patients (166 vs. 384 days, p less than 0.03). Three patients (19%) have evidence of OB after SLT, with one death. By virtue of equal intermediate-term outcomes, shorter waiting times, and better use of donor organs in comparison with HLT, LT should be offered whenever possible to patients with end-stage pulmonary parenchymal or vascular disease. The authors' pediatric LT and HLT experience (7 treatments in 6 patients) is the largest reported to date and demonstrates the utility of these procedures in this group. Chronic rejection (OB) remains the greatest impediment to long-term survival in both LT and HLT pts.
 ...
PMID:Lung and heart-lung transplantation. Evolution and new applications. 195 98

The association of positive antinuclear antibodies with the clinical and hemodynamic features of 43 patients with primary pulmonary hypertension and 16 patients with secondary pulmonary hypertension was investigated. Each patient had determinations of antinuclear antibodies using a KB cell substrate immunofluorescent test. Of the patients with primary pulmonary hypertension, 40% had positive antinuclear antibodies at titers of 1:80 dilutions or greater. There were no differences between patients with primary pulmonary hypertension and positive antinuclear antibodies compared with those with negative antinuclear antibodies in relation to clinical or hemodynamic status. A 6% incidence rate of antinuclear antibodies was found in patients with secondary pulmonary hypertension, similar to that in the normal population. The clinical, hemodynamic, serologic and histologic similarity between patients with primary pulmonary hypertension and those with unexplained pulmonary hypertension associated with collagen vascular disorders suggests that primary pulmonary hypertension in some patients may represent a collagen vascular disease confined to the lungs. The frequency of positive antinuclear antibody tests would place primary pulmonary hypertension between rheumatoid arthritis and scleroderma in the spectrum of collagen vascular diseases. Further studies are necessary, however, before one might expect that immunosuppressive therapy would be beneficial to these patients.
 ...
PMID:Antinuclear antibodies in primary pulmonary hypertension. 243 Oct 19

Much of the understanding of hypertensive pulmonary vascular disease comes from studies of primary pulmonary hypertension. The three subtypes of primary pulmonary hypertension, plexogenic pulmonary arteriopathy, thromboembolic pulmonary hypertension and venoocclusive disease, have served as a basis to understand the mechanisms and to develop treatments of all forms of pulmonary hypertension. However, many inconsistencies regarding presumed pulmonary vasoconstriction and recurrent embolization remain. With newer data on the influence of the endothelium on vascular responsiveness and thrombosis, it appears that older concepts regarding the pathophysiology of pulmonary hypertension need to be revised. Recent studies have shown that plexogenic pulmonary arteriopathy is associated with abnormalities of endothelial structure and function that could result in impaired release of endothelial derived relaxing factors. Thromboembolic pulmonary arteriopathy, or more properly thrombotic pulmonary hypertension, appears to be the result of endothelial cell injury that creates a procoagulant environment in the pulmonary vascular bed with the development of widespread eccentric intimal proliferation and thrombosis in situ. It is possible that the effectiveness of vasodilator or anticoagulant therapy depends on the nature of the endothelial injury. Secondary pulmonary hypertension without endothelial injury, such as that which occurs with hypoxic lung disease or mitral stenosis, appears more satisfactorily treated when the primary cause is reversed.
 ...
PMID:Pulmonary hypertension: a cellular basis for understanding the pathophysiology and treatment. 267 Oct 93

Qualitative and quantitative studies were performed on pulmonary blood vessels in lung tissue obtained by biopsy, pneumonectomy, or autopsy from 58 patients in the Registry of Primary Pulmonary Hypertension sponsored by the Heart, Lung, and Blood Institute of the National Institutes of Health. In 49 patients (84%), the hypertensive vascular disease involved predominantly or exclusively muscular pulmonary arteries and arterioles. In each of these 49 patients, pulmonary artery medial hypertrophy was observed, and in 48 patients, it was also associated with intimal or luminal lesions. On the basis of the predominant histopathologic features, 25 of the 48 patients were classified as having pulmonary arteriopathy with plexiform lesions characterized by a combination of concentric laminar intimal fibrosis, eccentric intimal fibrosis, and plexiform lesions; in nine of these 25, recanalized thrombi were also present. Pulmonary arteriopathy with thrombotic lesions, defined by the presence of both eccentric intimal fibrosis and recanalized thrombi but without plexiform lesions, was observed in 19 patients. Intimal fibrosis, either concentric or eccentric, without plexiform or thrombotic lesions was found in four patients. Among the remaining nine patients in the Registry, pulmonary veno-occlusive disease was present in seven and chronic pulmonary venous hypertension in one. Pulmonary blood vessels were microscopically normal in a lung biopsy specimen from another patient. In general, patients with plexiform lesions and those with veno-occlusive disease had a much poorer prognosis than patients with thrombotic lesions. The present study shows the existence of several distinct histopathologic patterns of pulmonary vascular disease in individuals with primary pulmonary hypertension diagnosed by standardized clinical and laboratory criteria.
 ...
PMID:Histopathology of primary pulmonary hypertension. A qualitative and quantitative study of pulmonary blood vessels from 58 patients in the National Heart, Lung, and Blood Institute, Primary Pulmonary Hypertension Registry. 280 80

Five patients with classic hemophilia were found to have primary pulmonary hypertension, a disorder not previously recognized in this population. All patients had had their coagulation disorder treated for 10 years or more with self-administered lyophilized concentrates of factor VIII, and all had antibodies to human immunodeficiency virus (HIV). Primary pulmonary hypertension was confirmed by histologic means at autopsy in one patient and by lung biopsy findings in another. In the other three patients, the findings are in agreement with this diagnosis. No patient had underlying cardiac or pulmonary disease, or clinical or pathologic evidence of collagen-vascular disease, vasculitis, parasitic disorders, hemoglobinopathy, or exposure to anorexigenic agents. Whether the primary pulmonary hypertension was related to treatment with lyophilized factor VIII, or to the presence of antibodies to HIV, or both, is unknown.
 ...
PMID:Primary pulmonary hypertension in patients with classic hemophilia. 280 26

Pulmonary mechanical function and gas exchange were studied in 33 patients with advanced pulmonary vascular disease, resulting from primary pulmonary hypertension in 18 cases and from Eisenmenger physiology in 15 cases. Evidence of airway obstruction was found in most patients. In addition, mean total lung capacity (TLC) was only 81.5% of predicted and 27% of our subjects had values of TLC less than one standard deviation below the mean predicted value. The mean value for transfer factor (TLCO) was 71.8% of predicted and appreciable arterial hypoxaemia was present, which was disproportionate to the mild derangements in pulmonary mechanics. Patients with Eisenmenger physiology had significantly lower values of arterial oxygen tension (PaO2) (p less than 0.05) and of maximum mid expiratory flow (p less than 0.05) and significantly higher pulmonary arterial pressure (p less than 0.05) than those with primary pulmonary hypertension, but no other variables were significantly different between the two subpopulations. It is concluded that advanced pulmonary vascular disease in patients with primary pulmonary hypertension and Eisenmenger physiology is associated not only with severe hypoxaemia but also with altered pulmonary mechanical function.
 ...
PMID:Pulmonary function in advanced pulmonary hypertension. 343 37

This review highlights newer insights into possible pathogenic mechanisms, clinical features, and treatment of primary pulmonary hypertension. A disease once believed to be found only in younger women, it has now been well documented to occur in both the young and elderly, with a female to male distribution of approximately 1.7:1 at all ages. Several possible etiologic mechanisms have recently been elucidated. Evidence has been forthcoming suggesting a possible role for thromboxane being produced by the pulmonary vascular bed, an underlying abnormality in clot lysis, the presence of antinuclear antibodies which could represent a collagen vascular disorder involving the lung, and a potential aggravating role of female hormones. Unfortunately, the major frustration with primary pulmonary hypertension remains its treatment. Some investigators suggest that anticoagulation may have beneficial effects on long-term survival, although this remains controversial. Most of the recently published articles on therapy have dealt with the use of vasodilators. A careful review of the effectiveness of vasodilators in these patients has failed to show that their chronic use alters either the patient's clinical course, survival, or the disease process itself. It does appear, however, that sustained beneficial effects can be realized in some patients if a substantial reduction in the pulmonary artery pressure is achieved with drug treatment. A thorough understanding of the physiologic characteristics of the pulmonary vascular bed is necessary in order to avoid misinterpreting the effects of vasodilators, which can also be detrimental. The development of vasodilators that are more specific for the pulmonary vascular bed may lead to better clinical results. Strategies for making an earlier diagnosis, however, may be equally important in our attempts to improve the prognosis.
 ...
PMID:Primary pulmonary hypertension: recent advances. 353 Sep 28

A wide range of pulmonary vascular imaging techniques are available for the diagnostic evaluation of patients with suspected pulmonary vascular disease. The characteristics of any "ideal" technique would include high sensitivity and specificity, safety, simplicity, and sequential applicability. To date, no single technique meets these ideal characteristics. Conventional pulmonary angiography remains the "gold standard" for the diagnosis of acute thromboembolic disease despite the introduction of newer techniques such as digital subtraction angiography and magnetic resonance imaging. Improved noninvasive lower extremity venous testing methods, particularly impedance plethysmography, and ventilation-perfusion scanning can play significant roles in the noninvasive diagnosis of acute pulmonary emboli when properly applied. Ventilation-perfusion scanning may also be useful as a screening test to differentiate possible primary pulmonary hypertension from chronic thromboembolic pulmonary hypertension. And, finally, angioscopy may be a useful adjunctive technique to detect chronic thromboembolic disease and determine operability. Optimal clinical decision-making, however, will continue to require the proper interpretation of adjunctive information obtained from the less-invasive techniques, applied with an understanding of the natural history of the various forms of pulmonary vascular disease and with a knowledge of the capabilities and shortcomings of the individual techniques.
 ...
PMID:Pulmonary vascular imaging. 355 87


<< Previous 1 2 3 4 5 6 7 Next >>