PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “THROMBOSIS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1991

Seminars in thrombosis, thrombolysis, and vascular biology. Part 2: Coagulation and thrombosis.

The hemostatic mechanism is a critical component of a normally functioning circulatory system, preventing life-threatening hemorrhage and assisting in the maintenance of vascular integrity. For longer than half a century, however, nonphysiological intravascular coagulation and thrombosis have been recognized as playing central roles in cardiovascular morbidity and mortality. In order to provide a conceptual framework for the use of antithrombotic therapy, the pathogenetic mechanisms underlying thrombotic events must be clearly understood. The purpose of this review is to define these mechanisms, and discuss the use of anticoagulants in both the prevention and treatment of cardiovascular diseases.

Anticoagulants↗
PubMed2001

Comparison of 3 and 6 months of oral anticoagulant therapy after a first episode of proximal deep vein thrombosis or pulmonary embolism and comparison of 6 and 12 weeks of therapy after isolated calf deep vein thrombosis.

BACKGROUND: The optimal duration of oral anticoagulant therapy after a first episode of venous thromboembolism remains controversial. METHODS AND RESULTS: We performed an open-label, randomized trial comparing a short oral anticoagulant course (3 months for proximal deep vein thrombosis [P-DVT] and/or pulmonary embolism [PE]; 6 weeks for isolated calf DVT [C-DVT]) with a long course of therapy (6 months for P-DVT/PE; 12 weeks for C-DVT). The outcome events were recurrences and major, minor, or fatal bleeding complications. A total of 736 patients were enrolled. There were 23 recurrences of venous thromboembolism in the short treatment group (6.4%) and 26 in the long treatment group (7.4%); the 2 treatment regimens had an equivalent effect. For the hemorrhage end point, the difference between the short and the long treatment groups was not significant: 15.5% versus 18.4% for all events (P=0.302), 1.7% versus 2.8% (P=0.291) for major events, and 13.9% versus 15.3% for minor bleeding. Subgroup analysis demonstrated that the rate of recurrence was lower for C-DVT than for P-DVT or PE. CONCLUSIONS: After isolated C-DVT, 6 weeks of oral anticoagulation is sufficient. For P-DVT or PE, we demonstrated an equivalence between 3 and 6 months of anticoagulant therapy. For patients with temporary risk factors who have a low risk of recurrence, 3 months of treatment seems to be sufficient. For patients with idiopathic venous thromboembolism or permanent risk factors who have a high risk of recurrence, other trials are necessary to assess prolonged therapy beyond 6 months.

Administration, Oral↗
PubMed1976

[Coronary atherosclerosis, coronary thrombosis and myocardial infarction in autopsy cases. 4th communication: coronary thrombosis (author's transl)].

28978 cases of young (after the 14th year of age) and adult patients autopsied during the period from 1.1 1951 until 31. 12. 1969 in our Institute were scored for coronary thrombosis and analysed concerning frequency and distribution of age and sex, resp. In this material the evidence of morphological changes was proved by longitudinal dissection of the coronary vessels. We analysed the age of thrombi, the localization and the grading of coronary vessels occlusions. Coronary thrombi were found in 2,31 per cent of all autopsies (2,81 per cent in males,1,31 per cent in females). Coronary thromboses showed an increase during the observation period. These thrombi were found more frequently in younger patients. Most of the thrombi (62,20 per cent) were localized in the Arteria coronaria sinistra, 37,80 per cent we found in the Arteria coronaria dextra. Fresh thrombi (57,51 per cent) and those being in organization (42,49 per cent) were not significantly different. Obturating thromboses showed an increase. The numbers of non-obturating thromboses decreased during the observation period. Our findings correspond to similar results published in literature.

Adolescent↗
PubMed2000

Exclusion of deep venous thrombosis with D-dimer testing--comparison of 13 D-dimer methods in 99 outpatients suspected of deep venous thrombosis using venography as reference standard.

In a direct assay comparison we evaluated the diagnostic performance of 10 novel D-Dimer assays for the exclusion of deep venous thrombosis (DVT). In addition, 3 conventional ELISA D-Dimer assays were included as reference tests. The study was performed in 99 consecutive outpatients referred to the emergency department for clinical suspicion of DVT. Venography was used as reference standard and demonstrated the presence of DVT in 50 patients (6 patients with isolated distal DVT and 44 patients with proximal DVT). The qualitative D-Dimer assays Minutex and SimpliRED and the quantitative BC DD showed overall sensitivities (for proximal and distal DVT) of only 80-83% with specificities that ranged from 87 to 94%. Overall sensitivity was 94% for the qualitative INSTANT I.A. and 98% for the quantitative Turbiquant at a cut-off level equal to the detection limit. Using different cut-off levels a sensitivity of 100% for proximal DVT and for proximal as well as distal DVT could be obtained for NycoCard, IL DD, Liatest, Tinaquant and VIDAS D-Dimer assays with specificities that ranged from 31% (NycoCard) to 71% (VIDAS) for proximal DVT and from 12% (NycoCard) to 47% (IL DD) for overall DVT. At a cut-off level equal to the upper limit of the reference range only Tinaquant and VIDAS showed a sensitivity of 100% for proximal as well as for distal DVT with a specificity of 39% and 41% respectively. The results of this study suggest that the VIDAS and Tinaquant D-Dimer assays have the highest sensitivity for the exclusion of DVT in outpatients. In outpatients that have a low or moderate pretest probability for DVT, these tests may be used in management studies where anticoagulation is withheld on the basis of D-Dimer testing alone.

Adult↗
PubMed2001

Traveller's thrombosis: a review of deep vein thrombosis associated with travel. The Air Transport Medicine Committee, Aerospace Medical Association.

There is an increasing suspicion among the travelling public and the international media of an association between the occurrence of deep venous thrombosis (DVT) and air travel. It was noted by the UK House of Lords Select Committee on Science and Technology that up to 20% of the total population may have some degree of increased clotting tendency. It follows that some air travellers are at risk of developing DVT when, or soon after, travelling. There have been no epidemiological studies published which show a statistically significant increase in cases of DVT when travelling in the absence of pre-existing risk factors. The literature was reviewed. Current evidence indicates that any association between symptomatic DVT and travel by air is weak, and the incidence is less than the impression given by recent media publicity.

Aircraft↗
PubMedDate not supplied

A new murine model of coronary artery thrombosis and role of interleukin-8 in the development of coronary thrombosis.

Occlusive vascular disease most often results from thrombosis superimposed on atherosclerotic plaque. In the case of an acute coronary syndrome including an acute myocardium infarction or an unstable angina pectoris thrombus in coronary artery takes significant part as known. There are few reports about animal models of acute coronary artery thrombi, because of the difficulties of operative significance. We have succeeded in making thrombus at murine coronary arteries with ferric chloride. Slight or moderate IL-8 expressions were found in the endothelial cells in the thrombus formed vessel analyzed by immunohistochemistry. The interleukin-8 (IL-8) receptor knockout mice formed the slight thrombus in coronary arteries treated with ferric chloride. We propose a role for IL-8 in the pathogenesis of acute coronary artery thrombi. This hypothesis lends itself to testing using interventions to influence IL-8 secretion and actions in the early phase of coronary thrombotic formation.

Animals↗
PubMed2005

A critical appraisal of non-invasive diagnosis and exclusion of deep vein thrombosis and pulmonary embolism in outpatients with suspected deep vein thrombosis or pulmonary embolism: how many tests do we need?

The requirement for a safe diagnostic strategy should be based on an overall posttest incidence of venous thromboembolism of less than 1% during 3 month follow-up. Compression ultrasonography (CUS) has a negative predictive value (NPV) of 97% to 98% indicating the need of repeated CUS testing. Serial CUS testing is safe but you have to repeat 100 CUS to find 1 or 2 CUS positive for deep vein thrombosis (DVT), which is not cost-effective indicating the need to improve the diagnostic work-up of DVT by the use of clinical score assessment and D-dimer testing. The combination of a less sensitive D-dimer test (SimpliRed) and low clinical score does not, whereas the combination of a sensitive D-dimer test (ELISA VIDAS or Tinaquant) and low clinical score does safely exclude DVT without the need of CUS. The combination of a first negative CUS and a negative less sensitive D-dimer test (SimpliRed) or a sensitive ELISA D-dimer at a higher cut off level of 1,000 ng/ml safely excludes DVT with a NPV of > 99% without the need to repeated CUS in about 60%. The sequential use of a sensitive D-dimer and clinical score assessment will safely reduce the need for CUS testing by 40% to 60%. Large prospective outcome studies demonstrate that one negative examination with complete duplex color ultrasonography (CCUS) of the proximal and distal veins of the affected leg with suspected DVT is safe to withhold anticoagulant treatment with a NPV of 99.5%. This indicates that CCUS is equal or superior to serial CUS or the combined use of clinical score, D-dimer testing and CUS. Pulmonary angiography is the gold standard for segmental pulmonary embolism (PE) but not for subsegmental PE. A normal perfusion lung scan and a normal rapid ELISA VIDAS D-dimer test safely exclude PE. Helical spiral CT detects all clinically relevant PE and a large number of alternative diagnoses in symptomatic patients with a non-diagnostic ventilation perfusion scan (VP-scan) or a high probability VP-scan. Single-slice helical CT as the primary diagnostic test in patients with suspected PE in 5 retrospective studies and in 3 prospective management studies indicate that the NPV of a normal helical spiral CT, a negative CUS of the legs together with a low or intermediate pretest clinical probability is 99%. Helical spiral CT can replace both the VP-scan and pulmonary angiography to safely rule in and out PE. The combination of clinical assessment, a rapid ELISA VIDAS D-dimer followed by CUS will reduce the need for helical spiral CT by 40% to 50%.

Ambulatory Care↗
PubMedDate not supplied

[Changes in plasma coagulation and fibrinolysis following cesarean section and relationship to deep venous thrombosis. Results of a randomized prospective comparative study with 6% hydroxyethyl starch 0.62 and low-dose heparin as thrombosis prophylaxis].

Routine postoperative monitoring of plasma coagulation and fibrinolysis system values after cesarean delivery in 191 women who did not develop thrombosis and 16 who did revealed a preoperative defect in the fibrinolysis (PAI, TAT) and inhibitor (AT III) systems. Significant postoperative correlations in the drop in antithrombin levels could not be explained solely by hemodilution. Moreover, a disturbance of the equilibrium of the alpha-2 increase and plasminogen was observed, favouring alpha-2 antiplasmin. Hydroxyethyl starch is capable of simultaneously influencing hypercoagulability and postoperative status. The only difference noted between the two groups of drugs was in the course of the PAI concentration (P less than 0.02). It would therefore appear logical in clinical practice to extend preoperative tests to include determination of the plasminogen activator inhibitor and the thrombin-antithrombin complex.

Adult↗
PubMed1996

[Right ventricular thrombosis and pulmonary thrombosis associated with venous-peritoneal diversion (Le Veen). Diagnosis with transesophageal echocardiography].

Central venous thrombosis (CVT) and pulmonary embolism (PE) are complications that have been reported in association with the use of venous-peritoneal shunts (Le Veen). CVT usually develops around the proximal end of the catheter; the clinical course is varied and usually requires venous imaging to confirm the diagnosis. We present a case of CVT associated with PE, in which the thrombus was located in the right ventricular cavity (distal to the catheter tip). Two-dimensional transesophageal echocardiography was used for diagnosis and follow-up.

Echocardiography, Transesophageal↗
PubMed1990

Association between plasma levels of tissue plasminogen activator and postoperative deep vein thrombosis--influence of prophylaxis with a low molecular weight heparin. The Venous Thrombosis Group.

In a prospective, randomized controlled study, tissue plasminogen activator (t-PA) and tissue plasminogen activator antigen (t-PA:ag) were measured pre- and postoperatively in 40 consecutive patients undergoing total hip replacement. Patients received either a subcutaneous injection of low molecular weight heparin or placebo once daily. Deep vein thrombosis was diagnosed by bilateral phlebography. Patients who developed postoperative thromboembolic complications had significantly lower preoperative t-PA activity levels than patients who did not develop such complications. No difference was observed between the two groups with respect to t-PA:ag. Thromboprophylaxis with low molecular weight heparin did not cause any significant changes in t-PA activity and t-PA:ag. This study in high risk patients indicates that impaired fibrinolysis may be associated with development of thromboembolic complications after operation.

Adult↗
PubMed1997

Pulmonary embolism in deep venous thrombosis of the upper extremity: more often in catheter-related thrombosis.

BACKGROUND: Pulmonary embolism (PE) is a major complication of deep venous thrombosis (DVT) of the lower extremities. The incidence is approximately 50%. The incidence of DVT of the upper extremity (DVTUE) is increasing mainly due to the increasing use of central venous catheters. The percentage of PE secondary to DVTUE is still being investigated. METHODS: The occurrence of PE in DVTUE was retrospectively analyzed in 78 patients with proven DVTUE. Furthermore, the literature was reviewed. RESULTS: Of the identified patients with DVTUE 16 showed a primary DVTUE and 62 a secondary DVTUE. Secondary DVTUE was catheter-related in 41 (60%), which is 53% of all DVTUE. In this study the percentage of PE as a complication of DVTUE was 6 (95% CI: 0.2-30) in primary DVTUE, 13 (95% CI: 6-24) in secondary DVTUE and 17 (95% CI: 7-32) in catheter-related DVTUE. The relative risk for PE of catheter-related DVTUE versus other causes was 3.4 (95% CI: 0.4-53.5). The overall percentage was 12 (95% CI: 5-21). The literature review showed a percentage of 7 (95% CI: 4-9) in the retrospective studies and 17 (95% CI: 12-23) in the prospective studies. CONCLUSIONS: Indwelling catheters are the most common cause of DVTUE. PE is not an uncommon complication of DVTUE, and is more common in catheter-related DVTUE. The difference between the incidence of PE in DVTUE and DVT of the lower extremity may be explained by a number of factors, such as differences in fibrinolytic activity, mechanical forces and venous flow patterns.

Adult↗
PubMed1990

Real-time B-mode ultrasonography in the diagnosis of postoperative deep vein thrombosis in non-symptomatic high-risk patients. The Venous Thrombosis Group.

In a prospective study of 61 patients who were undergoing elective total hip replacement, the accuracy of real-time B-mode ultrasonography (B-US) in the diagnosis of postoperative deep vein thrombosis (DVT) was compared with blindly assessed bilateral ascending phlebography. The overall sensitivity and specificity of ultrasound was 71 and 94%, and the positive and negative predictive values were 77 and 92%, respectively. The sensitivity and specificity for diagnosis of proximal DVT was 73 and 96%, respectively. Thrombi smaller than 1 cm were not detected. It is concluded that B-US may be used as a screening test for postoperative DVT after elective hip surgery.

Adult↗
PubMedDate not supplied

Induced thrombosis in the pig inferior vena cava: a model of deep venous thrombosis.

PURPOSE: To establish a new animal model of deep venous thrombosis. MATERIALS AND METHODS: Fifteen young pigs underwent temporary interruption of the inferior vena cava (IVC) below the entry of the right renal vein by means of either a silicone band (surgical technique, n = 6) or an intraluminal balloon catheter (endovascular technique, n = 9), followed by injection of absolute ethanol. Lumbar veins within 3 cm below the obstruction were ligated or occluded interventionally. The iatrogenic caval obstruction was relieved after 2 days. RESULTS: Procedure-related mortality was 33% (n = 2) and 11% (n = 1) for the surgical and endovascular groups, respectively. An adherent, occlusive thrombus was found in all four of the remaining surgically treated animals and in six of eight animals treated percutaneously. The IVC remained patent in two animals in whom balloon migration occurred. Severe caval stenosis invariably occurred after surgical banding. CONCLUSION: IVC thrombi suitable for the study of various recanalization therapies can be reliably created with this pig model.

Angioplasty, Balloon↗
PubMed1997

Treatment of deep vein thrombosis: is thrombosis regression a desirable endpoint?

Recent studies on the treatment of acute deep vein thrombosis (DVT) with low-molecular-weight heparins have demonstrated that a certain degree of early recanalization of thrombosed veins can be obtained which is higher than that observed under standard heparin treatment. Thrombolytic treatment of DVT is mainly advocated because a reduction of late sequelae of DVT is expected from early thrombolysis. It has been made likely by several small long-term studies that this expectation is true, but conclusive evidence is still missing. There are also large differences in the reported incidence of late postthrombotic syndrome after acute DVT. It seems likely that there is a minimal reopening rate which is required to be of possible clinical value to the individual patient. A 30% or higher reduction of the Marder score is at present used in several clinical trials as a sign of individual response to the treatment and may prove to be a useful clinical endpoint in these and in future studies. Validated methods to predict the late sequelae of acute DVT, mainly severe postthrombotic syndrome, do not yet exist. Foot plethysmography, air plethysmography, duplex sonography (peak velocity of venous reflux, valve competence), and venous pressure reduction under exercise are possible candidates to be used in future prospective trials. From the existing evidence it is very likely that a marked or total reduction of thrombi will reduce the incidence of postthrombotic syndromes. Clinical studies aiming at a high rate of venous recanalization by prolonged treatment with low-molecular-weight heparins are ongoing.

Heparin, Low-Molecular-Weight↗
PubMedDate not supplied

Cutaneous thrombosis, cerebrovascular thrombosis, and lupus anticoagulant--the Sneddon syndrome. Report of 10 cases.

Ten patients with circulating lupus anticoagulant who presented with cutaneous vascular disease and cerebrovascular disease are presented. Cutaneous manifestations were gangrene, thrombophlebitis, ulcers, and livedo reticularis. All 10 patients had cerebral infarction. The relationship between the cerebral and cutaneous vascular changes and the presence of lupus anticoagulant is supported by a common noninflammatory vascular thrombosis histologically in these patients and by the presence of similar pathologic and clinical findings in patients with the lupus anticoagulant syndrome.

Adult↗
PubMed1985

Unstable angina with fatal outcome: dynamic coronary thrombosis leading to infarction and/or sudden death. Autopsy evidence of recurrent mural thrombosis with peripheral embolization culminating in total vascular occlusion.

Extensive microscopic examination of epicardial arteries and myocardium was performed in 25 cases of sudden death due to acute coronary thrombosis. Eighty-one percent of the thrombi had a layered structure with thrombus material of differing age, indicating that they were formed successively by repeated mural deposits that caused progressive luminal narrowing over an extended period of time. This episodic growth of the thrombus was accompanied by intermittent fragmentation of thrombus in 73% of the cases, with peripheral embolization causing microembolic occlusion of small intramyocardial arteries associated with microinfarcts. The period of unstable angina before the final heart attack was, in all but one of 15 patients, characterized by such an ongoing thrombotic process in a major coronary artery where recurrent mural thrombus formation seemed to have alternated with intermittent thrombus fragmentation. The culmination of this "dynamic" thrombotic process in total vascular occlusion caused the final infarction and/or sudden death.

Adult↗
PubMed1998

Meta-analysis of the risk of venous thrombosis in individuals with antiphospholipid antibodies without underlying autoimmune disease or previous thrombosis.

Patients with systemic lupus erythematosus (SLE) and antiphospholipid antibodies (aPL) are at a greater risk for venous thromboembolism (VTE) than SLE patients without these antibodies. For patients without SLE there is a controversy about the risk associated with these antibodies and about their prognostic significance. We reviewed the degree of evidence and describe the odds ratio for VTE associated with aPL, namely the lupus anticoagulant (LA) and anticardiolipin antibodies (aCL), in patients without SLE. The study was a meta-analysis of seven observational studies of risk for antiphospholipid associated venous thromboembolism (VTE), excluding SLE patients. The strategies to identify published research included a computerized literature search and the review of citations in primarily relevant articles for the period 1983 to 1997. A summary of study characteristics and a critical appraisal of study quality were done. Summary odds ratios were obtained conducted using a random and a fixed effects-model. The overall odds ratio for aCL associated VTE obtained by fixed-effects model was 1.56 (95% CI, 1.10-2.24) and 1.64 (95% CI, 0.93-2.89) by random-effects model. The heterogeneity of these results appeared to be due in part to the detection limit of the aCL assay: the odds ratio was 3.21 (95% CI, 1.11-9.28) with both models when high titres only were considered. The overall odds ratio for LA associated VTE was 11.1 (95% CI, 3.81-32.3). In conclusion meta-analysis of the risk for antiphospholipid associated thrombosis demonstrated a higher risk in patients with the LA than in other patients. This risk was also higher than in patients with aCL even when high titres only were considered.

Antibodies, Antiphospholipid↗