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 91 records · Page 5Linked to original sources
PubMedDate not supplied

Experimental coronary artery thrombosis in the absence of thromboxane A2 synthesis: evidence for alternate pathways for coronary thrombosis.

The actions of the thromboxane synthetase inhibitor, U-63557A, were evaluated in vivo in anesthetized open-chest dogs by inducing left circumflex coronary artery (LCCA) thrombosis with low amperage electrical stimulation (100 microA for 6 h) of the intimal surface of the vessel, and ex vivo by assessing platelet aggregation and TXB2 production. U-63557A, 10 mg/kg + 5 mg/kg/h i.v., reduced ex vivo platelet aggregation in response to arachidonic acid (0.65 mM) by 93 +/- 2% (p less than 0.05, means +/- SEM), whereas the concurrent formation of TXB2 was decreased by 78 +/- 8% (p less than 0.05). TXB2 concentration also was reduced significantly in vivo as measured from coronary sinus blood samples; however, 6-keto-PGF1 alpha concentration was unchanged from predrug values. Despite the significant inhibition of platelet aggregation and TXB2 production, thrombus mass was not reduced: control, 32.0 +/- 5.9 mg (n = 7); U-63557A, 30.8 +/- 12.0 mg (n = 5, p = NS). These results suggest that U-63557A effectively inhibits TXA2 synthetase, but lacks antithrombotic activity in our experimental model. Therefore, substances other than TXA2 may be capable of mediating occlusive coronary artery thrombosis.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Double-blind, randomized comparison of systemic continuous infusion of 0.25 versus 0.50 mg/kg/24 h of alteplase over 3 to 7 days for treatment of deep venous thrombosis in heparinized patients: results of the European Thrombolysis with rt-PA in Venous Thrombosis (ETTT) trial.

Thirty-two patients with acute, proximal-vein thrombosis were treated with heparin and alteplase (0.25 versus 0.5 mg/kg/24 h during 3-7 days) in a randomized, double-blind, multicenter, European (ETTT) trial. The treatment resulted in a decrease of the venographic Marder's score from 18 (6-25) to 13 (2-24) units (median, range) in Group I (0.25 mg/kg/24 h, n = 15, median decrease 3.0, p = 0.32) and from 17.5 (3-33) to 15.5 (0-27) in Group II (0.5 mg/kg/24 h, n = 16, median decrease 4.0, p = 0.23). Comparison of the sequential venograms could be performed in 14 cases of Group I and in 15 cases in Group II. A minority of patients showed substantial partial recanalization of the initially obstructed veins on the control venogram (one in each treatment group) and most of the control venograms showed either thrombus size reductions (5 in Group I, 7 in Group II) or no change or even deterioration (8 in Group I, 7 in Group II). Major bleedings were observed in 7 patients (7/32, 22%), 5 of them occurring in Group II (5/17, 29%). Thus, the results of the ETTT trial show that the used low dosages of alteplase administered intravenously over 3-7 days in heparinized patients cannot be recommended as a treatment for patients with deep venous thrombosis of lower limbs and/or pelvis. Further studies are needed to define a more suitable dosage regimen of alteplase in this indication.

Adolescent↗
PubMedDate not supplied

Superficial venous thrombosis of the lower extremities co-existing with deep venous thrombosis. A phlebographic study on 57 cases.

The incidence of deep venous thrombosis (DVT) coexistent in patients suffering from superficial venous thrombosis (SVT) has not been well documented. In a series of 57 consecutive patients with SVT of the lower extremities treated in our Department in the last five years without any obvious clinical signs of co-existing DVT, an ascending phlebographic study was performed. Co-existent DVT was disclosed in 19.6% of the patients. There was no correlation between the location or the length of thrombus and the co-existence of DVT. Patients in whom SVT developed in existing varicose veins were younger in age and the incidence of co-existence of DVT was lower. Our findings show that SVT does not always have a benign course. The disclosure of a high incidence of co-existing DVT in our series suggests the necessity of the examination of the deep venous system in all the cases of SVT by using ultrasonic technics, triplex and preferably of the ascending phlebography. The disclosure of DVT in those cases makes the application of anticoagulant treatment mandatory.

Adult↗
PubMed1989

Comparison of real-time B-mode ultrasonography and bilateral ascending phlebography for detection of postoperative deep vein thrombosis following elective hip surgery. The Venous Thrombosis Group.

A prospective study compared real-time B-mode ultrasound examination with bilateral ascending phlebography in the diagnosis of postoperative deep vein thrombosis in 60 patients undergoing elective total hip replacement. The overall sensitivity and specificity of the ultrasound method were 54 and 91%, respectively, and the positive and negative predictive values were 83 and 69%, respectively. The rather low overall sensitivity of the ultrasound method in this study was due to difficulty in detecting thrombi smaller than 1 cm wherever they were located in the deep veins, and in diagnosing thrombi in the calf, regardless of their size. We conclude that real-time B-mode ultrasonography is a technique that can easily be used routinely for detection of postoperative DVT in hip surgery, but its sensitivity for proximal thrombosis (63%) is too low for it to be used alone.

Adult↗
PubMed1998

D-dimer strategy in thrombosis exclusion--a gold standard study in 100 patients suspected of deep venous thrombosis or pulmonary embolism: 8 DD methods compared.

DD are now recognized as a valuable tool to screen patients suspected of deep venous thrombosis or pulmonary embolism before carrying out a gold standard radiologic examination. The newest methods available claim to be able to ascertain the absence of thrombosis, but they have yet to prove their efficiency. We compared the performances of 3 reference ELISA methods (D-DI Asserachrom Stago, D-dimer Enzygnost Behring and Dimertest GOLD EIA Agen), 5 recent rapid methods (VIDAS D-Dimer bioMérieux, Instant IA Stago, Simplired Agen, Nycocard D-dimer Nycomed and Accuclot D-Dimer Sigma Diagnostics) and two routine latex methods (Dimertest American Diagnostica and FDP-Slidex bioMérieux) in 100 patients. One of the rapid quantitative methods was demonstrated to have a level of efficiency comparable to that of ELISA methods. Finally, the cost and efficiency of different strategies were evaluated, the association of a routine latex method with the VIDAS D-Dimer bioMérieux being proven to be the most efficient.

Adult↗
PubMed2003

Imaging characteristics of a novel technetium Tc 99m-labeled platelet glycoprotein IIb/IIIa receptor antagonist in patients With acute deep vein thrombosis or a history of deep vein thrombosis.

BACKGROUND: The diagnosis of recurrent deep vein thrombosis (DVT) is challenging. Imaging with radiolabeled peptides offers a new approach for detecting acute DVT. Technetium Tc 99m ((99m)Tc)-apcitide binds with high affinity and specificity to the glycoprotein IIb/IIIa receptors expressed on activated platelets and, therefore, (99m)Tc-apcitide scintigraphy should be negative with residual abnormalities caused by old, inactive thrombi and positive with new, active thrombi. METHODS: In a prospective multicenter study, (99m)Tc-apcitide imaging was performed on 38 patients with a newly diagnosed first DVT (group 1) and 40 patients with previous DVT, symptoms of postthrombotic syndrome, and chronic intraluminal abnormalities on ultrasonography (group 2). Images were interpreted in a blinded fashion by 2 experts and by newly trained nuclear medicine physicians. The sensitivity and specificity of (99m)Tc-apcitide were determined by calculating the proportion of scans in group 1 patients that were read as "positive for acute DVT" and the proportion of scans in group 2 patients that were read as "negative for acute DVT," respectively. RESULTS: When read by 2 experts, ( 99m)Tc-apcitide had a sensitivity of 92% for both readers and specificities of 82% and 90%. Agreement between the experts was excellent. However, the accuracy and interreader agreement for newly trained nuclear medicine physicians were lower. CONCLUSIONS: Technetium Tc 99m-apcitide scintigraphy has potential utility in suspected recurrent DVT because it detects most acute thrombi and has few false-positive results in patients with previous DVT. However, the accuracy appears to depend on the training and experience of the interpreters.

Acute Disease↗
PubMedDate not supplied

Deferment of objective assessment of deep vein thrombosis and pulmonary embolism without increased risk of thrombosis: a practical approach based on the pretest clinical model, D-dimer testing, and the use of low-molecular-weight heparins.

BACKGROUND: Treatment of patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) is problematic if diagnostic imaging is not immediately available. Pretest clinical probability (PCP) and D-dimer assessment can be used to identify patients for whom empirical protective anticoagulation is indicated. To evaluate whether PCP and D-dimer assessment, together with the use of low-molecular-weight heparins (LMWHs), allow objective appraisal of DVT and PE to be deferred for up to 72 hours, patients with suspected DVT and PE were prospectively examined. METHODS: Patients identified with a high PCP or a moderate PCP with positive D-dimer test results received a protective full-dose treatment of LMWH; the remaining patients were discharged without anticoagulant administration. However, all patients were scheduled to undergo objective tests for DVT or PE within 72 hours. Standard antithrombotic therapy was administered when deferred diagnostic tests confirmed venous thromboembolism. RESULTS: In total, 409 consecutive patients with suspected DVT and 124 with suspected PE were included in this study. A total of 23.8% (95% confidence interval [CI], 20.3%-27.3%) of patients had confirmed venous thromboembolism. At the short-term follow-up (72 hours), only a single thromboembolic event (0.2%; upper 95% CI, 0.6%) had occurred, whereas at the 3-month follow-up, 5 events (1.2%; 95% CI, 0.2%-2.1%) had occurred in patients in whom diagnosis of DVT or PE had previously been ruled out. None of the patients had major bleeding events. Ninety percent of patients were treated as outpatients. CONCLUSION: Our study demonstrates that this approach allows the safe deferral of diagnostic procedures for DVT and PE for up to 72 hours.

Adolescent↗
PubMed2003

Obstinate thrombosis during percutaneous coronary intervention in a case with heparin-induced thrombocytopenia with thrombosis syndrome successfully treated by argatroban anticoagulant therapy.

We describe a case of massive coronary thrombus after the coronary stenting due to heparin-induced thrombocytopenia with thrombosis syndrome (HITTS). Only argatroban was able to resolve the thrombus. This is the first case in which argatroban successfully treated massive thrombus during percutaneous coronary intervention in a patient with HITTS.

Angioplasty, Balloon, Coronary↗
PubMed1998

Syndromes of thrombosis and hypercoagulability. Congenital and acquired causes of thrombosis.

Blood coagulation protein and platelet defects are now known to account for up to ninety percent of unexplained venous thrombosis and up to seventy percent of unexplained arterial thrombotic or ischemic events. This article summarizes the common and uncommon blood protein and platelet defects which should be suspected, and searched for, in patients with such events. Defining such defects will have major impact on secondary prevention and duration of antithrombotic therapy in the afflicted patient and impact on primary prevention for identified family members in those harboring hereditary defects.

Antiphospholipid Syndrome↗
PubMed1997

Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus Conference on Prosthetic Valve Thrombosis.

OBJECTIVES: We sought to form a consensus recommendation for management of prosthetic valve thrombosis (PVT) from previous case and uncontrolled reports from a consensus of international specialists. BACKGROUND: PVT and thromboembolism relate to inadequate anticoagulation and valve type and location. PVT is suspected by history (dyspnea) and auscultation (muffled valve sounds or new murmurs) and confirmed by Doppler echocardiography showing a marked valve gradient. METHODS: A consensus conference was held to recommend management of left-sided PVT. RESULTS: Transesophageal Doppler echocardiography is used to visualize abnormal leaflet motion and the size, location and mobility of thrombus. Thrombolysis is used for high risk surgical candidates with left-sided PVT (New York Heart Association functional class III or IV) because cerebral thromboembolism may occur in 12% of patients. Duration of thrombolysis depends on resolution of pressure gradients and valve areas to near normal by Doppler echocardiography performed every few hours. Lysis is stopped after 72 or 24 h if there is no hemodynamic improvement (operation indicated). Heparin infusion with frequent measurement of activated partial thromboplastin time (aPTT) begins when aPTT is more than twice control levels and can be converted to warfarin (international normalized ratio [INR] 2.5 to 3.5) plus aspirin (81 to 100 mg/day). Patients in functional class I or II have lower surgical mortality, and those with large immobile thrombi on the prosthetic valve or left atrium have responded to endogenous lysis with combined subcutaneous heparin every 12 h (aPTT 55 to 80 s) plus warfarin (INR 2.5 to 3.5) for 1 to 6 months. Operation is advised for nonresponders or patients with mobile thrombi. CONCLUSIONS: Thrombolysis, followed by heparin, warfarin and aspirin, is advised for high risk surgical candidates with left-sided PVT.

Aortic Valve↗
PubMed1996

Use of low molecular weight heparin (dalteparin), once daily, for the treatment of deep vein thrombosis. A feasibility and health economic study in an outpatient setting. Swedish Venous Thrombosis Dalteparin Trial Group.

OBJECTIVES: To test the safety and feasibility of treating deep vein thrombosis (DVT) in an outpatient setting, using the low molecular weight heparin dalteparin, to calculate the potential and actual cost reductions achievable as a result of such a treatment regimen. DESIGN: An open, nonrandomized, multicentre trial. SETTING: Fourteen hospitals in central Sweden. SUBJECTS: Ambulant patients, aged 18 years or older. with symptomatic DVT in the leg, diagnosed using phlebography or ultrasound (Duplex-Doppler). INTERVENTIONS: Dalteparin (Fragmin) at a fixed dose of 200 i.u. kg-1 body weight, was administered once daily subcutaneously for at least 4 consecutive days. Treatment with warfarin was initiated from the first day of dalteparin administration. Outpatient treatment was encouraged whenever possible Financial calculations were performed independently at two hospitals, giving an average cost for all actions. OUTCOME MEASURES: Increasing severity of symptoms (or thromboembolic recurrences during the 3-months follow-up period), pulmonary embolism (PE), bleeding events, and death during the initial phase and follow-up period. RESULTS: Of 434 patients, 35% and 64% were treated in hospital within 24 and 72 h, respectively, and thereafter as outpatients. The overall frequency of serious complications was 0.92% (exact 95% confidence interval, 0.25-2.35%) during the initial phase and one patient suffered a PE and three patients had a recurrent DVT during the follow-up period. A cost reduction of 2705529 Swedish crowns (34.5%) was achieved in this study compared with traditional in-patient treatment. CONCLUSIONS: Dalteparin, administered subcutaneously, once daily, for the initial treatment of DVT yields large cost reductions and is well tolerated and effective in an outpatient setting.

Aged↗
PubMed2004

Risk factors for venous thrombosis in medical inpatients: validation of a thrombosis risk score.

BACKGROUND/OBJECTIVES: The occurrence of and risk factors for venous thrombosis (VT) complicating hospital admission in unselected medical inpatients have not been widely studied. PATIENTS AND METHODS: In a 400-bed teaching hospital we identified all cases of VT complicating hospital admission between September 2000 and September 2002 using discharge codes and chart review. Controls were randomly selected adult inpatients frequency matched to cases for medical service. RESULTS: The incidence of VT complicating hospital admission was 7.6 per 1000 admissions. On average, VT was diagnosed on the fifth hospital day. The median age of the 65 cases and 123 controls was 68 years and 45% were men. Cases had a 4-fold higher death rate than controls [95% confidence interval (CI) 1.9, 8.8]. At admission, trauma within 3 months, leg edema, pneumonia, platelet count > 350 x 10(3) mm(-3) and certain cancers were associated with risk of VT. Age, body mass index, and acute myocardial infarction were not associated with VT risk. One of three published VT risk models was able to risk stratify patients and was associated with a 2.6-fold increased risk of VT (95% CI 1.3, 5.5). Use of VT prophylaxis did not differ in cases and controls; prophylaxis was used < 1/3 of hospital days in 52% of patients. CONCLUSIONS: VT was common among medical inpatients. Of the risk factors identified, elevated platelet count has not been previously reported. Only one of three published risk scores was associated with risk of inpatient VT. Future study should improve upon risk prediction models for in-hospital VT among medical patients.

Adolescent↗
PubMed2001

Clinical features and prognostic factors of cerebral venous sinus thrombosis in a prospective series of 59 patients. For The Cerebral Venous Sinus Thrombosis Study Group.

The prognosis of cerebral venous sinus thrombosis (CVST) is variable, and outcome may range from complete recovery to death. Prognostic factors to predict outcome in the acute phase of CVST have not been analysed in a prospective study. Prognostic factors in patients enrolled in a clinical treatment trial were prospectively investigated. Poor outcome after 12 weeks, defined as death or dependency (Oxford handicap score > or =3), was used as the principle outcome measure. Univariate relations between possible prognostic factors and outcome at 12 weeks were analyzed with chi(2) tests. Treatment and all factors associated with prognosis (p< or = 0.25) were forced into a logistic regression model with a forward selection procedure. Fifty nine patients (50 women, nine men) were studied, with a mean age of 37 years (range 18 to 80 years). After 12 weeks 10 patients (17%) had a poor outcome. The univariate identified factors related to poor outcome were papilloedema, altered consciousness, coma, age older than 33 years, diagnostic delay < or =10 days, intracerebral haemorrhage, and involvement of the straight sinus. Isolated intracranial hypertension and a delta sign on CT were associated with good outcome. In the multivariate analysis coma and cerebral haemorrhage were significantly associated with a poor outcome, with odds ratios of 8.2 (95% confidence interval (95% CI) 1. 3-50.1) and 20.7 (95% CI 1.6-264.3) respectively. Involvement of the straight sinus was also weakly, but not significantly, associated with poor outcome. In conclusion, coma and intracerebral haemorrhage are independent predictors for poor outcome of CVST.

Adolescent↗
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↗