Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0034065 (pulmonary embolism)
 14,979 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An impaired fibrinolytic activity after a venous occlusion test is the most common abnormality associated with thomboembolic disease. To better characterize the causes of abnormal responses we have measured different fibrinolytic parameters, before and after 10 and 20 min of venous occlusion, in 77 patients with a history of idiopathic deep vein thrombosis and/or pulmonary embolism and in 38 healthy volunteers. The patients had a lower mean fibrinolytic response to venous occlusion than the controls and higher antigen levels of tissue-type plasminogen activator (t-PA:Ag) and plasminogen activator inhibitor type 1 (PAI-1:Ag). Before venous occlusion, PAI-1 levels were at a molar excess over those of t-PA in all patients and controls. After 20 min of venous occlusion, the release of t-PA from the vascular endothelium resulted in a molar excess of t-PA over PAI-1 in the majority of controls (72%) but only in a minority of patients (39%). To identify patients with fibrinolytic abnormalities, reference intervals (RI) for fibrinolytic activity, t-PA:Ag and PAI-1:Ag were established in healthy controls. None of the patients had low levels of t-PA:Ag, but 17 (22%) had elevated PAI-1:Ag levels before venous occlusion and 12 (16%) exhibited low fibrinolytic activity after 20 min of venous occlusion. Ten of these were among the 17 subjects with high PAI-1:Ag levels before venous occlusion. Thus, the measurement of PAI-1:Ag levels before venous occlusion (i.e. in samples taken without any stimulation) is a sensitive (83%) and specific (89%) assay for the detection of patients with an impaired fibrinolytic response to venous occlusion.
 ...
PMID:Hypofibrinolysis in patients with a history of idiopathic deep vein thrombosis and/or pulmonary embolism. 163 86

These recommendations for secondary prevention of clinical coronary cardiopathy are the result of a symposium attended by 46 experts belonging to the councils on arteriosclerosis, clinical cardiology, epidemiology, and prevention and rehabilitation of the International Society and Federation of Cardiology. Secondary prevention of coronary cardiopathy refers to measures designed to prevent deterioration or death in patients with clinical manifestations of coronary cardiopathy. Such measures in addition to drugs include health actions that may improve the status of various coronary risk factors: the patient's life style should stress maintenance of proper weight, regular physical exercise, reduction of saturated fats and cholesterol in the diet, and elimination of smoking and excessive alcohol consumption. It is considered reasonable to control hypertension through the most innocuous means possible, but findings of the few existing controlled studies of effects of treatment of hypertension in coronary cardiopathy are complex. Drug treatment may be necessary for most patients, but nondrug measures should be added when possible. Various proofs including results of some controlled studies justify the recommendations for reducing elevated levels of serum cholesterol and low density lipoprotein cholesterol through dietary measures. Optimum plasma cholesterol levels are 5.2 mmol/1 or less, and the upper limit is 5.7 mmol/1. The rules for secondary prevention are the same for diabetics as for nondiabetics, but some special precautions are necessary in diabetics. Habitual and vigorous physical activity has been associated with a decline in the incidence of coronary cardiopathy in different population studies, although there has been no demonstration that exercise can alter the progression of atherosclerosis or improve collateral circulation. Stress should be recognized as a risk factor and included in secondary prevention, but the concept that stress is the key risk factor in coronary events is in conflict with a large body of scientific evidence. Oral contraceptives (OCs) tend to increase boood pressure and weight as well as serum triglyceride levels, and to reduce glucose tolerance and high density lipoprotein cholesterol in some formulations. OCs also affect the integrity of the vascular endothelium and alter blood coagulation, fibrinolysis, and platelet function. These thrombogenic changes are intensified with age, especially after 35, and with smoking. OCs are innocuous in women under 35 with no history of venous or arterial disease or pulmonary embolism and who have normal blood pressure and serum cholesterol levels. Patients using OCs should control their blood pressure and weight and be alert to any symptoms of thrombotic episodes. The risk/benefit ratio of longterm estrogen treatment in meno- and postmenopausal women with coronary cardiopathy has not yet been established. Apart from 1 study in primates, there is no evidence that vasectomy should be considered either indicated or contraindicated for coronary patients. Beta blockers, platelet function inhibitors, anticoagulants, and other drugs are under active study for secondary prevention of coronary cardiopathy.
 ...
PMID:[Recommendations for secondary prevention of the clinical coronary cardiopathy]. 285 11

Pulmonary hypertension may develop whenever chronic obstruction of pulmonary arterial blood flow occurs. Although repeated pulmonary embolism is thought to be the usual underlying cause, there is little clinical evidence to support this theory. Studies of the pulmonary vascular endothelium have shown that perturbations of the normal endothelium can create a procoagulant environment, which could lead to the development of thrombosis in situ at the level of the large or smaller pulmonary vessels. Some patients develop proximal pulmonary thromboemboli, which may be the result of retrograde propagation of thrombus after an initial pulmonary embolus. Others present with unexplained pulmonary hypertension secondary to thrombotic occlusion of the pulmonary microvasculature. A perfusion lung scan will show abnormalities that should lead to correct clinical diagnosis and confirmatory evaluation. Thromboendarterectomy in selected cases provides dramatic clinical improvement in patients with proximal thromboemboli. Vasodilators may be effective in some patients with obstruction at the arteriolar level. Both groups should be treated with chronic warfarin anticoagulant therapy to protect against progression of thromboembolism.
 ...
PMID:Pulmonary hypertension from chronic pulmonary thromboembolism. 327 15

A review of a series of clinical and experimental investigations established that the incidence of deep venous thrombosis and of pulmonary embolism after total hip replacement surgery was lower in patients given continuous lumbar epidural anaesthesia than in others with general anaesthesia. The thromboprophylactic effect of continuous lumbar epidural anaesthesia is explained by its beneficial influence on all factors of the triad proposed by Virchow, viz. blood flow, factors within the blood itself, and the vascular endothelium. Continuous lumbar epidural anaesthesia is associated with hyperkinetic blood flow in the major vessels of the lower limbs, lessened tendency to coagulation of the blood and better preservation of fibrinolysis function. Other characteristics include an inhibitory action on platelet aggregation and stabilizing effect on leukocytes and endothelial cells--effects exerted by the local anaesthetics per se. The smaller blood loss and thus the lower transfusion requirements during continuous lumbar epidural anaesthesia may also play a beneficial role as a thromboprophylactic factor.
 ...
PMID:The role of lumbar epidural anaesthesia as antithrombotic prophylaxis in total hip replacement. 393 4

Focus in this discussion of pulmonary embolism is on the following: risk factors (age, heredity and blood type, obesity, estrogen and oral contraceptive use/pregnancy, cardiovascular disease, cancer, and other risk factors); pathophysiology and presenting symptoms; laboratory procedures and findings (radiography, electrocardiography, lung scanning, and evaluation of lower extremity veins); treatment modalities (heparin therapy, thrombolysis, and surgery); and prevention. Pulmonary embolism may be the primary cause or a major contributory cause in as many as 200,000 deaths per year in the US. Most of these deaths occur in patients in whom the diagnosis is not suspected and, thus, not treated. The mortality rate for untreated pulmonary embolism is approximately 30%. 90% of patients survive the initial embolic event, but the correct diagnosis is made in no more than 2/3 of cases. Risk factors for the development of deep venous thrombosis are based upon the Virchow-Aschoff postulates, which include: trauma or disruption of the vein wall; stasis of blood flow in the veins; and increased coagulability of the blood. More than 85-90% of all pulmonary emboli originate from deep venous thromboses in the popliteal and femoral deep veins. Other important, although less frequent, sites of origin of venous thromboembolism include the pelvic veins, the renal and hepatic veins, the axillary veins in the upper extremities, and the right atrium. Accurate diagnosis and effective prevention and treatment depend on the clinician's awareness of risk factors for development of deep vein thrombosis. Estrogen may accelerate intimal proliferation in arteries and veins, and it may also increase permeability of venous vascular endothelium. The risk of thromboembolism increases as the dose of estrogen increases. Both pregnancy and oral contraceptive use significantly decrease venous tone and the velocity of blood flow in the calf of the leg. Appropriate treatment includes thrombolytic therapy for patients with massive pulmonary embolism, which results in hypotension or shock. Anticoagulant therapy with herapin followed by an oral anticoagulant is the primary treatment for most patients with submassive emboli in which there is less cardiovascular compromise. When thrombolytic therapy is used, it should always be followed by anticoagulant therapy. Prevention of primary or recurrent deep vein thrombosis is directed toward improving venous blood flow and reducing hypercoagulability.
 ...
PMID:Pulmonary embolism: incidence, diagnosis, prevention, and treatment. 398 Feb 63

Three cases of deep venous thrombosis following varicella infection are described which were successfully treated with bed rest and anticoagulants. Two of these patients had severe pulmonary manifestations of varicella and the third was complicated by pulmonary embolism. Deep vein thrombosis is an uncommon systemic manifestation of varicella, possibly associated with vascular endothelium wall damage caused by varicella zoster virus infection.
 ...
PMID:Three cases of varicella thrombophlebitis as a complication of varicella zoster virus infection. 846 61

We have observed a deep venous thrombosis with pulmonary embolism in a young woman receiving low-dose oral contraceptives; this adverse drug effect was not associated with some risk factor and, in particular, with a demonstrable congenital or acquired clotting abnormality. It is reported that EP can induce deep venous thrombosis with different mechanisms, as hemorheological changes with subsequent poor clearance of locally activated clotting factors, or an increase of platelet or leukocytes aggregation, or a direct effect on some clotting factor; furthermore, it is well known that oral contraceptives may induce antibodies to synthetic hormones, with detection of circulating immune complexes, that might produce thrombosis by damaging the vascular endothelium or interfering with clotting factors or platelet aggregation. Moreover, only a familial history of thrombosis or a past history of recurrent deep venous thrombosis, especially in young age, may justify a broad and highly expensive screening of latent clotting abnormalities, that may significantly increase the risk of vascular thrombosis with the use of oral contraceptives.
 ...
PMID:[Low-dose oral contraceptives and pulmonary embolism: a case report]. 876 50

We examined hemostatic molecular markers in various thrombotic disorders. The efficacy of treatment in relation to the disseminated intravascular coagulation (DIC) score when the treatment was begun showed that greater efficacy was achieved in Pre-DIC than in DIC patients. The outcome was poorer with increasing DIC score, suggesting that early treatment is important. The sensitivity in some of molecular markers was high for both DIC and Pre-DIC. Receiver operating characteristic analysis suggest that soluble fibrin monomer level could be the most useful marker for the diagnosis of DIC. In examination of these markers in deep vein thrombosis, pulmonary embolism, acute myocardial infarction, and cerebral infarction, plasminogen activator inhibitor-1 and activated protein C-protein C inhibitor complex were useful marker for the diagnosis. Increased plasma GMP-140 was suggested to be the activation of platelets. The patients with high levels of plasma thrombomodulin (TM) considered to be a marker of vascular endothelial injuries became poor outcome. We will term these patients with high TM as systemic vascular endothelium injuries syndrome, and treat those by protecting the vascular endothelium.
 ...
PMID:[Study of hemostatic molecular marker]. 913 93

The pulmonary complications remain the prime cause of morbidity and mortality in sickle cell disease. The pathogenetic mechanisms consists both of an alteration of the rheological properties of the blood, the existence of a hypercoagulability state and above all specific interactions between the abnormal sickle cells and the vascular endothelium and a dysregulation of the vascular reactivity in which nitrous oxide intervenes. The acute chest syndrome (ACS) is characterised by chest pain with dyspnoea and recent radiological abnormalities and it is an acute lung complication whose problem is one of aetiology. The infectious pneumonias are rarely documented. On the other hand, alveolar hypoventilation linked to infarcts of the thoracic ribs, thoracoabdominal trauma, subdiaphragmatic pain, the administration of analgesics causing respiratory depression, obesity or sleep disturbance are frequent causes of ACS. Bronchoalveolar lavage has revealed a frequency of fat emboli following infarcts in the long bones. Pulmonary emboli is rarely a cause. Pulmonary thrombosis is a serious complication, the diagnosis is difficult and is seen in a predisposed clinical setting. The treatment of ACS rests on controlled hydration and antibiotic therapy, oxygen therapy and controlled analgesic therapy. The indications for blood transfusion and for exchange transfusion merits a better evaluation. In the long term patients with sickle cell disease present with a failure of normal thoracopulmonary growth with a restrictive ventilatory defect and progressive diminution in the transfer factor of carbon monoxide with age. A history of ACS favours chronic lung disease. Pulmonary arterial hypertension is less frequent.
 ...
PMID:[The sickle cell anemia lung from childhood to adulthood]. 960 86

Deep vein thrombosis (DVT) and pulmonary embolism (PE) are distinct but related aspects of the same dynamic disease process known as venous thromboembolism (VTE). An estimated 200,000 new cases occur in the United States every year, including 94,000 with PE, resulting in an incidence of 23 per 100,000 patients per year-cases. Without treatment, pulmonary embolism is associated with a mortality rate of approximately 30%, causing nearly 50,000 deaths per year. Moreover, based on post-mortem studies, two-thirds of the patients with pulmonary emboli remain undiagnosed. Clinically, PE may present as (1) isolated dyspnea, (2) pleuritic pain and/or hemoptysis, and (3) circulatory collapse. However, clinical history and examination can be notoriously misleading in reaching a diagnosis. A number of acquired etiologic risk factors (predispositions) are associated with a tendency to develop VTE. These include increasing age, immobilization, surgery, trauma, hospital or nursing home confinement, malignancy, neurologic disease with extremity paresis, as well as certain types of oral contraception and hormone replacement therapy. In addition, a variety of genetic risk factors, such as factor V Leiden, protein S or C deficiency have also been identified. However, in at least half of the instances, no predisposing factors can be identified (idiopathic PE). In the majority of cases thromboemboli originate in the deep veins of the calf or pelvis. The pathogenic conditions for VTE comprise a triad of factors and include (1) venous stasis, (2) hypercoagulable states, and (3) vascular endothelium injury. Occlusion of pulmonary arteries has variable and transient clinical and pathophysiologic consequences, involving both mechanical and reflex effects of vascular occlusion with a consecutive perfusion defect as well as the release of vasoactive and other inflammatory mediators. The objectives of this article are to present an overview of the etiologic and pathogenic factors promoting VTE as well as the pathophysiologic and inflammatory processes following PE.
 ...
PMID:Principle mechanisms underlying venous thromboembolism: epidemiology, risk factors, pathophysiology and pathogenesis. 1258 87


1 2 Next >>