Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “THROMBOSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,135 records · Page 63Linked to original sources
PubMed1996

Cerebral Venous Thrombosis - A New Diagnosis in Travel Medicine?

Cerebral venous thrombosis is a syndrome seen in association with a large number of disease processes. The commonest reported causes in adults are oral contraception,1 pregnancy and complications associated with the postpartum period,2 systemic malignancy,3 and infection.4 In approximately 20% of adult cases reported during the past 20 years no etiology was established.5 Cerebral venous thrombosis can be caused by similar mechanisms, such as venous thrombosis, occurring elsewhere in the body, e.g., blood vessel wall alterations attributable to inflammation, infection, or invasion of malignant cells, as well as from changes in blood flow due to dehydration and changes in the coagulability of the blood (e.g., from use of oral contraception). PC Gates and HJM Barnett list 38 causes of cerebral venous thrombosis that were proven by angiography or autopsy. One item on their list was dehydration/ hyperpyrexia.5 Recently thrombosis of the venae saphena or femoralis/iliaca has been reported to occur in long distance air travelers.6 We would like to report on five patients (out of 15) in whom cerebral venous thrombosis was causatively linked with either long distance air travel alone, air travel and diarrhea, or air travel and exposure to tropical heat.

Journal Article↗
PubMed1970

Diagnostic accuracy in venous thrombosis.

A group of 111 surgical patients at high risk of venous thrombosis were studied after operation by independent clinical assessment and with (125)I-fibrinogen to detect venous thrombosis. Almost half of the patients developed venous thrombosis. Of these, two-thirds were not suspected clinically despite careful scrutiny. In the patients in whom a clinical diagnosis of venous thrombosis was made this diagnosis was falsely positive in a quarter. More than half of all thrombotic episodes were detectable on the day after operation.The prevalence of venous thrombosis, together with the difficulty in diagnosing it, strongly supports the argument that a reduction in the incidence of pulmonary embolism must depend on widespread adoption of effective prophylaxis, especially in the large number of patients at high risk of venous thrombosis. Prophylactic trials must be objectively assessed, and it is in this field that the (125)I-fibrinogen technique probably has the most to offer.

Adult↗
PubMed1976

Preoperative prediction of postoperative deep vein thrombosis.

A range of clinical data was obtained from 124 patients about to undergo operation and several coagulation tests were performed. No patient received prophylaxis for deep vein thrombosis, and isotopic scanning after operation showed that 20 patients had developed thrombosis. a simiple prognostic index for predicting which patients would develop postoperative deep vein thrombosis was constructed using the clinical and coagulation data obtained before operation. The five variables with the best predictive power-euglobulin lysis time, age, presence of varicose veins, fibrin related antigen, and percentage overweight-produced an equation that identfied 95% of those who developed deep vein thrombosis and misallocated only 28% of those who did not develop thrombosis. In view of the complications that low-dose heparin and dextran can cause, giving prophylaxis to under a third of the patients who will not develop deep vein thrombosis is clearly better than giving it to all.

Adult↗
PubMed1985

Fragment E1 labeled with I-123 in the detection of venous thrombosis.

Fragment E1, which has been shown to have specific binding affinity for thrombi in an animal model, was investigated in humans for its safety and ability to bind to venous thrombi. Human Fragment E1 was labeled with I-123 and administered intravenously to patients with proved or suspected deep vein thrombosis. The vascular distribution of radioactivity was documented by obtaining gamma camera images of the patients' legs for 30 minutes following administration of I-123-Fragment E1. All patients (n = 5) with documented venous thrombi had rapid localization of labeled Fragment E1 in the area of thrombus. Patients without evidence of thrombi (n = 5) showed no focal localization, although two of these patients showed diffuse uptake along the length of the veins, due to superficial phlebitis. Analysis of blood samples in four patients indicated that disappearance of Fragment E1 from the circulation was more rapid in individuals with thrombosis (t 1/2 = 20 min) than in individuals without thrombosis (t 1/2 = 90 min), and a radiolabeled species of high molecular weight was found in patients with thrombosis but was absent from patients without thrombosis. These early results suggest that radiolabeled Fragment E1 is a safe and potentially valuable agent for the rapid detection of venous thrombosis.

Adolescent↗
PubMed1998

Deep venous thrombosis: gradient-recalled-echo MR imaging changes over time--experience in 10 patients.

PURPOSE: To determine the gradient-recalled-echo (GRE) magnetic resonance (MR) imaging changes caused by intraluminal thrombus of the lower extremities over time and to establish GRE MR imaging criteria to help distinguish acute from previous deep venous thrombosis. MATERIALS AND METHODS: Four women and six men, aged 38-76 years, underwent GRE MR imaging two to four time after the original diagnosis of deep venous thrombosis; eight also underwent confirmatory ultrasonography at that time. Follow-up was 3 months to 1 1/2 years. All patients were treated with anticoagulants. Evidence of thrombus, signal intensity characteristics, and MR imaging appearance were evaluated. RESULTS: Acute thrombosis was identified as an occlusion or prominent filling defect within the vessel. The luminal diameter of thrombosed veins was equal to or larger than that of a corresponding, unaffected vessel in each case. Acute thrombus signal intensity tended to be decreased initially and increase over time. Residual changes due to thrombosis included the web formation (n = 3), luminal narrowing (n = 4), and wall thickening and/or slow flow (n = 5). Vessels in three patients reverted to normal. CONCLUSION: GRE MR imaging demonstrated progressive changes of venous thrombus over time. These criteria may help distinguish acute deep venous thrombosis from the residual changes of previous thrombosis.

Adult↗
PubMed1976

Impedance plethysmography using the occlusive cuff technique in the diagnosis of venous thrombosis.

Impedance plethysmography using the cuff technique has been compared with venography in 346 consecutive patients with suspected venous thromboembolism. The limbs were classified according to the venographic results as no thrombosis, proximal (popliteal, femoral, or iliac) vein thrombosis, and calf thrombosis. A discriminant analysis was performed. The impedance plethysmographic result was normal in 386 of 397 limbs which were normal on venography, a specificity of 97%, and abnormal in 124 of 133 limbs which showed proximal vein thrombosis, a sensitivity of 93%. Seventy-three of 88 limbs with calf vein thrombi and a normal impedance plethysmographic result. The sensitivity in 29 limbs with asymptomatic proximal vein thrombosis was 83%. Impedance plethysmography is an accurate method for detecting proximal vein thrombosis but has limitations which include the possibility of false positive results due to arterial insufficiency and muscle tension.

Adolescent↗
PubMed1989

Diagnosis of deep venous thrombosis. A prospective study comparing duplex scanning to contrast venography.

Duplex scanning has been proposed as a safe alternative to contrast venography for diagnosing deep venous thrombosis, but its accuracy has not been proved. In this prospective, double-blind study of 47 patients, the sensitivity and specificity of duplex scan criteria were determined relative to contrast venography for lower extremity deep venous thrombosis. Criteria considered to show the presence of deep venous thrombosis included visualization of thrombus (T), absence of spontaneous flow by Doppler ultrasonography (F), absence of phasicity of flow with respiration (P), and incompressibility of the vein with probe pressure (VC). When analyzed individually, the variables T and F had low sensitivities (50% and 76%) but high specificities (92% and 100%). VC had low values for both (79% and 67%, respectively). The best single variable was P (sensitivity and specificity = 92%). The best combinations of variables were T+P (sensitivity = 95%, specificity = 83%), T+F+P (sensitivity = 95%, specificity = 83%), F+P (sensitivity and specificity = 92%), and F+T (sensitivity = 92%, specificity = 87%). The low specificity of vein incompressibility was secondary to cases in which normal veins were difficult to compress in the thigh. All false-negative cases were from isolated calf vein thrombi. We conclude that isolated criteria from duplex scanning should not be used to diagnose deep venous thrombosis. In cases of suspected calf vein thrombosis, repeat duplex examination should be obtained in 3-4 days to determine the most appropriate therapy. In equivocal cases of proximal vein thrombosis, a contrast venogram should be obtained.

Adult↗
PubMed1989

Real-time ultrasound for diagnosis of symptomatic venous thrombosis and for screening of patients at risk: correlation with ascending conventional venography.

This is a prospective study of 108 patients in two distinct groups undergoing real-time ultrasonography (US) and ascending conventional venography within the same day. The two patient groups consisted of the following: Those patients evaluated because of suspicion of deep venous thrombosis of lower limbs (69 patients) and those at high risk for venous thrombosis (19 patients with a recent hip fracture, 20 with a suspected pulmonary embolism). In the diagnosis group 48 patients had venographic evidence of thrombosis. The predictive value of abnormal findings from real-time US was 97%, and that of a negative study was 75%. Thus, real-time US may have a role as a diagnostic procedure, to be followed by x-ray venography in patients with negative US results. By contrast, real-time US is far less sensitive as a screening test in patients without clinical evidence of thrombosis. Only 3 of 9 patients with thrombosis were detected, with a 50% sensitivity for proximal vein thrombosis. Therefore, the use of real-time US for screening high-risk patients must be limited to very high risk patients in whom other tests are ineffective (as in hip surgery).

Aged↗
PubMed1981

The natural history and aetiology of deep vein thrombosis after total hip replacement.

A study of the natural history and aetiology of deep vein thrombosis in 499 patients after total hip replacement is presented. Deep vein thrombosis was diagnosed by scanning the leg for 125Iodine-labelled fibrinogen for a period of 14 to 18 days and by ascending phlebography. It has been shown that deep vein thrombosis occurs ater than in patients who have undergone abdominal operations, and the risk period is longer. The peak of onset of thrombosis is on the fourth day after the hip replacement. Attempts at prophylaxis using subcutaneous heparin or intermittent pneumatic compression of the calves delay the appearance of thrombosis. Analysis of possible aetiology factors shows that the age of the patient, the degenerative disease of the hip, the surgical approach, and under-transfusion of blood, all have a significant effect on the incidence of thrombosis.

Age Factors↗
PubMed1989

Deep vein thrombosis after total hip replacement. A comparison between spinal and general anaesthesia.

The effect of hypobaric spinal anaesthesia or narcotic-halothane-relaxant general anaesthesia on the incidence of postoperative deep vein thrombosis was studied in 140 elective total hip replacements in a prospective randomised manner. Deep vein thrombosis was diagnosed using impedance plethysmography and the 125I fibrinogen uptake test, combined, in selected cases, with ascending contrast venography. The overall incidence of deep vein thrombosis was 20%. Nine patients (13%) developed deep vein thrombosis in the spinal group and nineteen (27%) in the general anaesthetic group (p less than 0.05). The incidences of proximal thrombosis and of bilateral thrombi were also less with spinal anaesthesia than with general anaesthesia. It is concluded that spinal anaesthesia reduces the risks of postoperative thromboembolism in hip replacement surgery. The presence of varicose veins, being a non-smoker and having a low body mass index were associated with an increased incidence of deep vein thrombosis.

Aged↗
PubMed1984

Detection of active left ventricular thrombosis during acute myocardial infarction using indium-111 platelet scintigraphy.

Platelet scintigraphy with radioactive indium-111 may be used both to identify and to reflect the activity of thrombin in vivo in man. Forty-one patients with acute myocardial infarction were studied for active left ventricular thrombosis by platelet scintigraphy and followed until in-hospital death, discharge, or same-admission cardiac surgery for evidence of systemic embolization. A total of 4.7 +/- 2.4 X 10(9) platelets (mean +/- 1 SD) labelled with 381 mu Ci +/- 51 mu Ci of indium-111 was injected intravenously at 91 +/- 88 hours following the onset of chest pain. Patients were imaged in multiple views on the day of and three to four days after injection of the platelet suspension. Group 1 (n = 29) had transmural myocardial infarctions, of which 21 were anterior (peak total level of creatine phosphokinase [CPK], 2,272 +/- 2,026 IU; mean +/- 1 SD) and eight were inferior (CPK level, 1,673 +/- 589 IU). Group 2 (n = 12) had subendocardial myocardial infarctions (CPK level 799 +/- 751 IU). Those with subendocardial and transmural inferior myocardial infarctions had neither left ventricular thrombosis nor emboli. Ten (48 percent) of 21 with anterior transmural myocardial infarctions had left ventricular thrombosis by platelet scintigraphy. Three with and one without such thrombosis by scintigraphy had acute neurologic episodes. In the group with anterior myocardial infarctions, seven of ten patients with and four of 11 without left ventricular thrombosis received heparin subcutaneously (chi 2 = 1.22 [Yates correction]; p greater than 0.30). We conclude that platelet scintigraphy may be used to monitor antiplatelet and anticoagulant therapy in patients with anterior transmural myocardial infarctions who are at risk for left ventricular thrombosis and systemic embolization.

Aged↗
PubMed1996

Effect of delayed admission to the hospital on the preoperative prevalence of deep-vein thrombosis associated with fractures about the hip.

Thirteen (10 per cent) of 133 patients who had venography on admission to the hospital for a fracture about the hip had radiographic evidence of deep-vein thrombosis. Only seven (6 per cent) of the 122 patients who were seen at the hospital within two days after the fracture had evidence of thrombosis. However, six of the eleven patients who had a delay of more than two days between the fracture and admission to the hospital had evidence of thrombosis. Although there was no significant difference between these two groups with respect to the mean age, sex distribution, frequency of fracture type, or history of deep-vein thrombosis, there was a significant difference in the prevalence of thrombosis in the patients who had a delay before admission to the hospital compared with those who did not (p<0.001). These results suggest that there is a substantial risk of venous thromboembolic disease in patients who have a fracture about the hip, regardless of whether or not they have had an operation, and that this risk increases if the time to presentation is delayed. Consequently, patients for whom there was a delay between a fracture about the hip and admission to the hospital should be considered to be at high risk for, and should be evaluated for, deep-vein thrombosis preoperatively.

Age Factors↗
PubMed1992

George W. Holmes Lecture. Deep venous thrombosis and pulmonary embolism: correlative evaluation and therapeutic implications.

Deep venous thrombosis and pulmonary embolism are significant causes of morbidity and mortality in the United States; estimates range from 120,000 to 150,000 deaths annually. Although usually symptomatic, deep venous thrombosis can be clinically occult, in part due to incomplete obstruction or in part related to duplication, triplication, and fenestration anomalies, primarily of the superficial femoral or popliteal vein. Additionally, pulmonary emboli caused by deep venous thrombosis may be clinically silent. Because of therapeutic implications, especially indications for insertion of inferior vena caval filters, comprehensive assessments of both the disease process (i.e., deep venous thrombosis) and the complication (i.e., pulmonary emboli) are important. Thus, when a pulmonary embolus is the presenting process, correlative assessment of deep venous thrombosis, even in the absence of symptoms or signs in the lower extremity, may be of therapeutic significance. Conversely, when deep venous thrombosis of the lower extremities involving the popliteal or superficial femoral vein is the presenting process, correlative assessment of the pulmonary circulation, even when no pulmonary symptoms or signs are present, may be of therapeutic significance. Relative to the diagnosis of pulmonary embolism, the roles of assays of D-dimer, ventilation-perfusion lung scans, and segmental occlusion studies of the pulmonary circulation are discussed. Finally, the indications for insertion of inferior vena caval filters above the renal veins are presented and examples are shown.

Adult↗
PubMed1995

Anatomic distribution of venous thrombosis in patients with antiphospholipid antibody: imaging findings.

OBJECTIVE: Antiphospholipid antibodies are immunoglobulins that cross-react with phospholipid within cell membranes. These antibodies have been associated with a hypercoagulable state manifested by early stroke, frequent arterial and venous thromboses, recurrent fetal loss, thrombocytopenia, and livedo reticularis (antiphospholipid syndrome). The purpose of this study was to determine the anatomic distribution of venous thrombosis in patients with antiphospholipid antibodies as seen on imaging examinations. MATERIALS AND METHODS: We retrospectively reviewed the laboratory results of patients tested for antiphospholipid antibodies at a tertiary referral center during the period January 1992 to April 1994. This review revealed 228 patients with antiphospholipid antibodies. We excluded patients with systemic lupus erythematosus or any other medical condition associated with a hypercoagulable state and patients over 65 years old. Thirty-one of the remaining 73 patients had undergone imaging studies of the CNS or non-CNS venous system. Radiologic studies (contrast angiography or venography, MR angiography or venography, or Doppler sonography) were examined for the presence of venous thrombosis. Nineteen patients--11 men and eight women, 18-62 years old (average age, 38 years)--with venous thromboses were identified. RESULTS: Twelve patients had non-CNS thrombosis alone, three had CNS thrombosis alone, and four had both CNS and non-CNS thromboses. Locations of non-CNS thromboses included deep veins of the legs (nine occurrences), pulmonary vessels (five), and large veins in the thorax or abdomen (six). Three of these patients had documented thromboses at other sites. Twelve patients had recurrent thrombotic events (six with multiple recurrences), including five with arterial thromboses and two with both venous and arterial thromboses and stroke. Among patients with CNS involvement, five had documented thromboses (four dural sinus, one arterial) and two had arterial distribution strokes demonstrated by CT. Two patients with only non-CNS thromboses had either seizures or migraines. CONCLUSION: Deep veins of the leg were the most common site of venous thrombosis. The thoracic and abdominal venous system and the dural sinuses--unusual sites of thrombosis in the general population--are other common sites. Antiphospholipid antibodies should be suspected when thromboses are found in these locations in the absence of other known risk factors, or when found in combination with arterial thromboses or CNS ischemic disease in young or middle-aged patients.

Adolescent↗
PubMed2001

Using dual-detector helical CT angiography to detect deep venous thrombosis in patients with suspicion of pulmonary embolism: diagnostic value and additional findings.

OBJECTIVE: The purpose of this study was to assess the value of dual-slice helical CT angiography in detecting deep venous thrombosis in patients in whom acute pulmonary embolism was suspected and to describe the additional extrathoracic findings. SUBJECTS AND METHODS: Sixty-five consecutive patients were examined for suspected pulmonary embolism using helical CT of the chest (2.7-mm collimation; table speed, 7.5 mm/sec; 100-140 mL of contrast medium injected at a rate of 3 mL/sec) followed by CT of the lower limbs (6.5-mm collimation; table speed, 10 mm/sec) without any additional contrast medium injection. Sequential scanning of the abdomen was performed using 10-mm collimation and an interval of 40 mm. Color Doppler sonography of the lower limbs was done within 24 hr of CT by two radiologists who were unaware of CT findings. Results of CT venography were compared with those of Doppler sonography and with phlebography or repeated focalized sonography in cases of discrepancy. RESULTS: Twenty-two patients had pulmonary embolism revealed on chest CT. Sixteen patients had a deep venous thrombosis. Thirteen patients with pulmonary embolism had a deep venous thrombosis. Three patients with deep venous thrombosis had no pulmonary embolism. Sensitivity and specificity for diagnosing deep venous thrombosis with CT was 93% and 97%, respectively (kappa = 0.88). Additional extrathoracic findings were observed in four patients. CONCLUSION: Combined CT venography with dual-slice scanning is an accurate method to diagnose deep venous thrombosis that may reveal additional imaging findings in some patients with possible pulmonary embolism.

Acute Disease↗
PubMed1994

Efficacy and safety of enoxaparin to prevent deep venous thrombosis after hip replacement surgery. Enoxaparin Clinical Trial Group.

OBJECTIVE: To determine the most effective and safe dose of enoxaparin to prevent deep venous thrombosis in high-risk surgical patients. DESIGN: A double-blind, randomized, multicenter clinical trial. SETTING: Private, university, and government hospitals in the United States. PATIENTS: 572 patients having elective hip replacement surgery, 568 of whom received study medication and had efficacy data available for evaluation. INTERVENTIONS: Patients were randomly assigned to one of three subcutaneous enoxaparin regimens: 10 mg once daily (161 patients); 40 mg once daily (199 patients); and 30 mg every 12 hours (208 patients). Treatment was initiated within 24 hours after surgery and continued for as long as 7 days. Treatment with 10 mg enoxaparin once daily was discontinued prematurely after an interim analysis showed an increased deep venous thrombosis incidence in this treatment group. MEASUREMENTS: Efficacy was determined by bilateral lower extremity venography, noninvasive vascular imaging methods, or clinical evidence on day 7 of treatment or earlier if clinically indicated. RESULTS: Deep venous thrombosis occurred in 25% (40 of 161) of the patients who received 10 mg of enoxaparin once daily; in 14% (27 of 199) of those receiving 40 mg of enoxaparin once daily; and in 11% (22 of 208) in those receiving 30 mg of enoxaparin every 12 hours. The incidence of deep venous thrombosis was significantly higher in patients who received 10 mg of enoxaparin once daily compared with those who received 40 mg of enoxaparin once daily (P = 0.02) or those who received 30 mg of enoxaparin every 12 hours (P < 0.001). The difference between the patients who received 40 mg once daily and those who received 30 mg every 12 hours was not significant. Only two cases of pulmonary embolism were diagnosed, one in patients receiving 40 mg of enoxaparin and one in those receiving 10 mg once daily. The incidence of hemorrhagic complications differed significantly between patients who received 10 mg of enoxaparin once daily (5%, 8 of 161 patients) and those who received 30 mg of enoxaparin every 12 hours (13%, 26 of 208; P < 0.05). CONCLUSIONS: After surgery, enoxaparin, 40 mg once daily or 30 mg every 12 hours, is more effective than a regimen of 10 mg once daily to prevent deep venous thrombosis in patients having elective hip replacement surgery. The regimens of 40 mg once daily and 30 mg every 12 hours provided prophylaxis similar to the most effective drug treatments previously reported. The incidence of hemorrhagic episodes with the regimens of 40 mg once daily and 30 mg twice daily was higher than that observed with 10 mg once daily; however, major hemorrhage occurred in only 4% to 5% of patients receiving the higher-dose regimens. The risk-to-benefit ratio supports the use of enoxaparin as a therapeutic agent to prevent deep venous thrombosis in these patients.

Aged↗
PubMed1975

Renal vein thrombosis and nephrotic syndrome. A prospective study of 36 adult patients.

During 2 years we studied 36 of 41 consecutive patients with nephrotic syndrome. Twelve (Group 1) had renal vein thrombosis; the renal pathology was membranous glomerulonephritis in 10 and membranoproliferative glomerulonephritis in 2. Eighteen without renal vein thrombosis (Group 2) had either membranous (10 patients) or membranoproliferative (8 patients) glomerulonephritis. Clinical presentation, laboratory data, renal function, renal histology, and immunopathology were similar in both groups; thromboembolic phenomena were frequent. Ten of 12 patients with renal vein thrombosis were given oral anticoagulants and followed for 4 to 24 months. None died or had thromboembolic episodes. The results show that one third of the patients with nephrotic syndrome associated with either membranous or membranoproliferative glomerulonephritis had renal vein thrombosis, and there were no clinical, laboratory, histological, or immunopathological finding(s) diagnostic of renal vein thrombosis. Our data indicate that renal vein thrombosis is a frequent complication in nephrotic syndrome and membranous or membranoproliferative glomerulonephritis.

Adolescent↗
PubMed1976

[Value of intermittent pneumatic compression of the calves for the prevention of postoperative thrombosis of the deep veins].

Six prospective, randomized studies using intermittent pneumatic compression of the calf for prevention of postoperative deep vein thrombosis are available and have been analyzed. In 4 studies a significant reduction in the incidence of deep vein thrombosis could be demonstrated. Compared to controls, the reduction in the deep vein thrombosis rate by intermittent compression is about 60%. The frequency of deep vein thrombosis is lower if the patients are treated not only intraoperatively but also for 24-28 h postoperatively. The difference in deep vein thrombosis rate between these two schedules is statistically probable significant. No definite statement can be made regarding the efficacy of deep vein thrombosis prevention in patients with malignant disease, since here the results are controversial. No studies are available on the effect of intermittent pneumatic compression of the leg on the incidence of fatal postoperative pulmonary emboli. This method must therefore be regarded as an interesting alternative in clinical investigation.

Humans↗