Thrombi

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Thrombi

  • atrial thrombi
  • coronary thrombi
  • platelet thrombi


  • Selected Abstracts


    Hypereosinophilic Syndrome Presenting with Biventricular Cardiac Thrombi

    ECHOCARDIOGRAPHY, Issue 6 2010
    Ankur Lodha M.D.
    Hypereosinophilic syndrome is a rare condition characterized by idiopathic eosinophilia with organ system involvement. Cardiac involvement portends a less favorable prognosis as it can be complicated by development of heart failure, valvular dysfunction, and restrictive cardiomyopathy. We present a rare case of hypereosinophilic syndrome with FIP1L1/PDGFRA fusion in a 50-year-old male associated with thrombus in left and right ventricle. (Echocardiography 2010;27:E57-E59) [source]


    Is Transesophageal Echocardiography Necessary before D.C. Cardioversion in Patients with a Normal Transthoracic Echocardiogram?

    ECHOCARDIOGRAPHY, Issue 4 2007
    Mohsen Sharifi M.D.
    Purpose: Transesophageal echocardiography has emerged as an accepted approach before D.C. cardioversion for atrial fibrillation. The frequency of atrial thrombi detected on transesophageal echocardiography has varied from 7% to 23%. Many patients undergoing transesophageal echocardiography have had a previous transthoracic echocardiogram. Though transthoracic echocardiography has a low yield for the detection of intracardiac thrombi, it is highly accurate in diagnosing a structurally abnormal heart. The purpose of this study was to assess the frequency of thrombi detected by transesophageal echocardiography in patients with an entirely normal transthoracic echocardiogram and hence the advocacy of a selective approach in performing transesophageal echocardiography in patients undergoing D.C. cardioversion for atrial fibrillation. Methods: 112 consecutive patients with atrial fibrillation who had undergone transesophageal echocardiography before D.C. cardioversion were evaluated. They all had a transthoracic echocardiogram within the 2 months preceding their transesophageal echocardiogram. Based on their transthoracic echocardiographic study, they were divided into two groups: Group 1 consisted of patients with a normal transthoracic echocardiogram and Group 2, those with an abnormal study. Results: Thrombi or spontaneous echo contrast were found in 14 of 112 patients (16%). All however were detected in Group 2 patients. There was no patient with a normal transthoracic echocardiogram who had thrombus on his/her transesophageal echocardiogram. Conclusions: Our results suggest that a selective approach may be exercised in the use of transesophageal echocardiography prior to D.C. cardioversion for atrial fibrillation. Patients with an entirely "normal" transthoracic echocardiogram may proceed directly to cardioversion without a precardioversion transesophageal echocardiogram. [source]


    Abciximab Treatment for Obstructive Prosthetic Aortic and Mitral Valve Thrombosis in the Presence of Large Thrombi, Cardiogenic Shock, and Acute Evolving Embolic Stroke

    ECHOCARDIOGRAPHY, Issue 1 2004
    Atiar M Rahman M.D., Ph.D.
    Obstructive thrombosis of left-sided mechanical prosthetic valves is a life-threatening complication. Intravenous thrombolytic therapy is contraindicated due to risk of clot embolization and surgical treatment is often required for hemodynamically unstable patients. We report for the first time the successful use of abciximab in the management of a patient in cardiogenic shock with multiple prosthetic valve obstructive thrombosis and evolving embolic stroke. Serial Doppler echocardiography and cinefluoroscopy demonstrated resolution of thrombi, improvements in transvalvular gradients and improvement in leaflet motion. This observation suggests abciximab should be considered as a therapeutic option in the treatment of obstructed prosthetic heart valves. (ECHOCARDIOGRAPHY, Volume 21, January 2004) [source]


    Usefulness of Live/Real Time Three-Dimensional Transthoracic Echocardiography in Evaluation of Prosthetic Valve Function

    ECHOCARDIOGRAPHY, Issue 10 2009
    Preeti Singh M.D.
    We studied 31 patients with prosthetic valves (PVs) using two-dimensional and three-dimensional transthorathic echocardiography (2DTTE and 3DTTE, respectively) in order to determine whether 3DTTE provides an incremental value on top of 2DTTE in the evaluation of these patients. With 3DTTE both leaflets of the St. Jude mechanical PV can be visualized simultaneously, thereby increasing the diagnostic confidence in excluding valvular abnormalities and overcoming the well-known limitations of 2DTTE in the examination of PVs, which heavily relies on Doppler. Three-dimensional transthorathic echocardiography provides a more comprehensive evaluation of PV regurgitation than 2DTTE with its ability to more precisely quantify PV regurgitation, in determining the mechanism causing regurgitation, and in localizing the regurgitant defect. Furthermore, 3DTTE is superior in identifying, quantifying, and localizing PV thrombi and vegetations, in addition to the unique feature of providing a look inside mass lesions by serial sectioning. These preliminary results suggest the superiority of 3DTTE over 2DTTE in the evaluation of PVs and that it provides incremental knowledge to the echocardiographer. [source]


    Incremental Value of Live/Real Time Three-Dimensional Transthoracic Echocardiography in the Assessment of Right Ventricular Masses

    ECHOCARDIOGRAPHY, Issue 5 2009
    Venkataramana K. Reddy M.D.
    This case series demonstrates the incremental value of three-dimensional transthoracic echocardiography (3D TTE) over two-dimensional transthoracic echocardiography (2D TTE) in the assessment of 11 patients with right ventricular (RV) masses or mass-like lesions (three cases of RV thrombus, one myxoma, one fibroma, one lipoma, one chordoma, and one sarcoma and three cases of RV noncompaction, which are considered to be mass-like in nature). 3D TTE was of incremental value in the assessment of these masses in that 3D TTE has the capacity to section the mass and view it from multiple angles, giving the examiner a more comprehensive assessment of the mass. This was particularly helpful in the cases of thrombi, as the presence of echolucencies indicated clot lysis. In addition, certainty in the number of thrombi present was an advantage of 3D TTE. Also, sectioning of cardiac tumors allowed more confidence in narrowing the differential diagnosis of the etiology of the mass. In addition, 3D TTE allowed us to identify precise location of the attachments of the masses as well as to determine whether there were mobile components to the mass. Another noteworthy advantage of 3D TTE was that the volumes of the masses could be calculated. Additionally, the findings by 3D TTE correlated well with pathologic examination of RV tumors, and some of the masses measured larger by 3D TTE than by 2D TTE, which was also validated in one case by surgery. As in the case of RV fibroma, another advantage was that 3D TTE actually identified more masses than 2D TTE. RV noncompaction was also well studied, and the assessment with 3D TTE helped to give a more definitive diagnosis in these patients. [source]


    Value of Transesophageal 3D Echocardiography as an Adjunct to Conventional 2D Imaging in Preoperative Evaluation of Cardiac Masses

    ECHOCARDIOGRAPHY, Issue 6 2008
    Silvana Müller M.D.
    Background: This study sought to compare three-dimensional (3D) and two-dimensional (2D) transesophageal echocardiography (TEE) to assess intracardiac masses. It was hypothesized that 3D TEE would reveal incremental information for surgical and nonsurgical management. Methods: In 41 patients presenting with intracardiac masses (17 thrombi, 15 myxomas, 2 lymphomas, 2 caseous calcifications of the mitral valve and one each of hypernephroma, hepatocellular carcinoma, rhabdomyosarcoma, lipoma, and fibroelastoma), 2D and 3D TEE were performed, aiming to assess the surface characteristics of the lesions, their relationship to surrounding structures, and attachments. Diagnoses were made by histopathology (n = 28), by computed tomography (n = 8), or by magnetic resonance imaging (n = 5). Benefit was categorized as follows: (A) New information obtained through 3D TEE; (B) helpful unique views but no additional findings compared to 2D TEE; (C) results equivalent to 2D TEE; (D) 3D TEE missed 2D findings. Results: In 15 subjects (37%), 3D TEE revealed one or more items of additional information (category A) regarding type and site of attachment (n = 9, 22%), surface features (n = 6, 15%), and spatial relationship to surrounding structures (n = 8, 20%). In at least 18% of all intracardiac masses, 3D TEE can be expected to deliver supplementary information. In six patients, additional findings led to decisions deviating from those made on the basis of 2D TEE. In 11 subjects (27%), 3D echocardiographic findings were categorized as "B." Conclusions: Information revealed by 3D imaging facilitates therapeutic decision making and especially the choice of an optimal surgical access prior to removal of intracardiac masses. [source]


    Clinical and Echocardiographic Risk Factors for Embolization in the Presence of Left Atrial Thrombus

    ECHOCARDIOGRAPHY, Issue 5 2007
    Ela Sahinbas Kavlak
    Aims: The aim of our study was to evaluate the factors leading to embolization in patients with left atrial thrombi (LAT). With this purpose, we retrospectively analyzed clinical, transthoracic, transesophageal echocardiographic data of patients with LAT in the transesophageal echocardiographic evaluation. Methods and Results: One hundred ninety-two patients with LAT not on anticoagulant therapy were divided into two groups according to the presence of prior ischemic stroke. The group with ischemic stroke included more patients with sinus rhythm and less patients with mitral stenosis. They had smaller left atrial diameter, more left atrial appendage spontaneous echo-contrast, higher appendage ejection fraction, and emptying velocity. Conclusion: Once the thrombus has been formed, cerebral embolization seems to be higher in patients with relatively preserved appendage ejection fraction and emptying velocity. Presence of atrial appendage spontaneous echo-contrast also favor embolization. Factors leading to embolization seem to differ in some respects from the causes of thrombus formation. [source]


    Is Transesophageal Echocardiography Necessary before D.C. Cardioversion in Patients with a Normal Transthoracic Echocardiogram?

    ECHOCARDIOGRAPHY, Issue 4 2007
    Mohsen Sharifi M.D.
    Purpose: Transesophageal echocardiography has emerged as an accepted approach before D.C. cardioversion for atrial fibrillation. The frequency of atrial thrombi detected on transesophageal echocardiography has varied from 7% to 23%. Many patients undergoing transesophageal echocardiography have had a previous transthoracic echocardiogram. Though transthoracic echocardiography has a low yield for the detection of intracardiac thrombi, it is highly accurate in diagnosing a structurally abnormal heart. The purpose of this study was to assess the frequency of thrombi detected by transesophageal echocardiography in patients with an entirely normal transthoracic echocardiogram and hence the advocacy of a selective approach in performing transesophageal echocardiography in patients undergoing D.C. cardioversion for atrial fibrillation. Methods: 112 consecutive patients with atrial fibrillation who had undergone transesophageal echocardiography before D.C. cardioversion were evaluated. They all had a transthoracic echocardiogram within the 2 months preceding their transesophageal echocardiogram. Based on their transthoracic echocardiographic study, they were divided into two groups: Group 1 consisted of patients with a normal transthoracic echocardiogram and Group 2, those with an abnormal study. Results: Thrombi or spontaneous echo contrast were found in 14 of 112 patients (16%). All however were detected in Group 2 patients. There was no patient with a normal transthoracic echocardiogram who had thrombus on his/her transesophageal echocardiogram. Conclusions: Our results suggest that a selective approach may be exercised in the use of transesophageal echocardiography prior to D.C. cardioversion for atrial fibrillation. Patients with an entirely "normal" transthoracic echocardiogram may proceed directly to cardioversion without a precardioversion transesophageal echocardiogram. [source]


    Routine Transesophageal Echocardiography for the Evaluation of Cerebral Emboli in Elderly Patients

    ECHOCARDIOGRAPHY, Issue 9 2005
    Sergey Vitebskiy M.D.
    Background: Approximately 20% of cerebral infarctions are cardioembolic in nature. Transesophageal echocardiography (TEE) is widely regarded as the initial study of choice for evaluating cardiac source of embolism. Although the majority of cerebrovascular accidents occur in elderly patients, the value of TEE in this population is poorly defined. Methods: We compared 491 patients older than 65 years with suspected embolic stroke or transient ischemic attack (TIA) who had undergone TEE evaluation between April 2000 and February 2004 to an age-, sex-, and time-matched control group that consisted of 252 patients. Studies were reviewed for abnormalities associated with thromboembolic disease. Results: The overall incidence of stroke risk factors was significantly higher in the study than in the control group. However, the four patients with left atrial thrombi had a history of atrial fibrillation. Although ascending and aortic arch sessile atheromata were observed more frequently in the study than control group, there were no significant differences in the incidence of either complex or mobile aortic atheromata. The incidence of atrial septal aneurysm was higher in the stroke/TIA group, but not in association with patent foramen ovale. Finally, there were also no differences in the incidence of spontaneous echocontrast, and/or patent foramen ovale between study and control groups. Conclusions: We conclude: (1) There is a higher incidence of abnormalities implicated as sources of thromboembolic disease on TEE in elderly patients with cerebral infarctions, but (2) this incidence is driven by the presence of sessile aortic atheroma and atrial septal aneurysm. Until the benefits of specific therapies for these conditions are known, routine TEE in elderly patients with suspected embolic neurological events appears to be unwarranted. [source]


    Abciximab Treatment for Obstructive Prosthetic Aortic and Mitral Valve Thrombosis in the Presence of Large Thrombi, Cardiogenic Shock, and Acute Evolving Embolic Stroke

    ECHOCARDIOGRAPHY, Issue 1 2004
    Atiar M Rahman M.D., Ph.D.
    Obstructive thrombosis of left-sided mechanical prosthetic valves is a life-threatening complication. Intravenous thrombolytic therapy is contraindicated due to risk of clot embolization and surgical treatment is often required for hemodynamically unstable patients. We report for the first time the successful use of abciximab in the management of a patient in cardiogenic shock with multiple prosthetic valve obstructive thrombosis and evolving embolic stroke. Serial Doppler echocardiography and cinefluoroscopy demonstrated resolution of thrombi, improvements in transvalvular gradients and improvement in leaflet motion. This observation suggests abciximab should be considered as a therapeutic option in the treatment of obstructed prosthetic heart valves. (ECHOCARDIOGRAPHY, Volume 21, January 2004) [source]


    Course of Intraatrial Thrombi Resolution Using Transesophageal Echocardiography

    ECHOCARDIOGRAPHY, Issue 2 2003
    Jennifer A. Larsen M.D.
    Thromboembolic events are associated with atrial fibrillation and with cardioversion to sinus rhythm. Although studies have demonstrated the risk of this complication is reduced by a 3-week period of anticoagulation prior to cardioversion, limited data have suggested a longer period of anticoagulation is necessary for thrombus resolution. We identified and followed 25 patients noted to have intraatrial thrombi on an initial transesophageal echocardiogram (TEE) who subsequently had a follow-up TEE. The majority of patients had a single thrombus, often but not uniformly located in the left atrial appendage with the largest found in those patients with mitral stenosis. Repeat TEE was performed at a mean of 4 ± 6 months and persistent thrombus was noted in 19 of 25 patients (76%). Seven of 19 patients with persistent thrombi were cardioverted and one of these patients had a neurologic event following the procedure (14%). The only findings associated with persistent thrombus were the presence of mitral valve disease and atrial fibrillation.. Our findings suggest that intraatrial thrombi do not generally resolve following several weeks of anticoagulation and that persistent left-sided intraatrial thrombi may be associated with an increased risk for events following cardioversion. Given that a TEE-guided approach to cardioversion is being utilized more frequently, it may be important to determine thrombus characteristics on follow-up that would be predictive of embolic events following cardioversion. (ECHOCARDIOGRAPHY, Volume 20, February 2003) [source]


    Autocrine motility factor enhances hepatoma cell invasion across the basement membrane through activation of ,1 integrins

    HEPATOLOGY, Issue 1 2001
    Takuji Torimura
    Autocrine motility factor/phosphohexose isomerase (AMF/PHI) is a cytokine that is linked to tumor invasion and metastasis. In hepatocellular carcinoma (HCC) tissues, hepatoma cells produce AMF/PHI and its receptor, Mr 78,000 glycoprotein (gp78), is strongly detected in hepatoma cells invading into the stroma and tumor thrombi in the portal vein. Here, we investigated the mechanism of hepatoma cell invasion through Matrigel induced by AMF/PHI using 3 hepatoma cell lines. Production of AMF/PHI, phosphorylation of MEK1/2, and Rho activity were investigated by immunoblotting. Expression of AMF/PHI and gp78 was observed by confocal fluorescence microscopy. The influence of AMF/PHI on activated integrin ,1 subunit expression was evaluated by flow cytometry. Changes in invasion, adhesion, and motility induced by AMF/PHI were evaluated using chemoinvasion, adhesion, and phagokinetic track motility assays. The effect of AMF/PHI on matrix metalloproteinase (MMP) secretion was evaluated by gelatin zymography. Hepatoma cells produced AMF/PHI and expressed gp78. Although AMF/PHI was ubiquitously detected, gp78 was strongly expressed in migrating cells. AMF/PHI induced up-regulation of activated integrin ,1 subunit expression. AMF/PHI stimulated hepatoma cell invasion through Matrigel, and stimulated the adhesion, motility, and MMP-2 secretion of hepatoma cells. The latter effects were suppressed by the function-blocking antibody for integrin ,1 subunit. AMF/PHI also enhanced Rho activity and the phosphorylation of MEK1 and MEK 2. Our results indicate that AMF/PHI enhances hepatoma cell invasion through Matrigel in an autocrine manner by stimulating the adhesion, motility, and MMP-2 secretion of these cells through activation of ,1 integrins. [source]


    Cerebral emboli and paradoxical embolisation in dementia: a pilot study

    INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 1 2005
    Nitin Purandare
    Abstract Background The causes of the common dementias remain unknown. Paradoxical embolisation of the cerebral circulation by venous thrombi passing through venous to arterial shunts (v-aCS) in the heart or pulmonary circulation is known to occur in cryptogenic stroke and post-operative confusion following hip replacement. Objectives To explore the role of paradoxical embolisation in dementia by investigating for cerebral emboli, venous to arterial circulation shunt (v-aCS) and carotid artery disease. Methods Forty-one patients with dementia (24 Alzheimer's AD and 17 vascular VaD) diagnosed using DSM-IV criteria and 16 controls underwent transcranial Doppler (TCD) detection of spontaneous cerebral emboli in both middle cerebral arteries. A v-aCS was detected by intravenous injection of an air/saline ultrasound contrast at rest and after provocation by coughing and Valsalva's manoeuvre. Carotid artery disease was assessed by duplex imaging. Results Cerebral emboli were detected in 11 (27.5%) dementia patients compared with one (7%) control (p,=,0.15) with emboli being most frequent in VaD (41%) compared to controls [OR (95% CI): 10.5 (1.1, 98.9), p,=,0.04]. A v-aCS was detected in 25 (61%) patients and seven (44%) controls (p,=,0.24). In dementia patients with cerebral emboli; v-aCS was detected in seven (64%) and moderate to severe carotid stenosis was present in three (30%). Conclusion Cerebral emboli and v-aCS may be more frequent in patients with both VaD and AD than in controls, which suggest paradoxical embolisation as a potential mechanism for cerebral damage. This pilot study justifies a definitive case-control study. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Application of cardiopulmonary bypass for resection of renal cell carcinoma and adrenocortical carcinoma extending into the right atrium

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2006
    TATSUMASA OCHI
    Aim:, The application of cardiopulmonary bypass to atrial involvement represents an important advance that has improved the safety and technical efficacy of a difficult surgical undertaking. Our experiences of the management of extended thrombi into the right atrium in patients with retroperitoneal malignancy using a cardiopulmonary bypass were discussed. Methods:, Data were reviewed for five patients (two men and three women; mean age, 60.4 years; range, 49,79 years) with retroperitoneal tumors displaying intracardiac tumor extension. Tumors originated in the right kidney in four patients, and in left adrenal gland in one patient. Cardiopulmonary bypass was used in all cases. Results:, Mean total blood loss was 6059 mL. Mean operative time was 14.7 h. No intra- or postoperative complications due to surgical technique were encountered, and no significant bleeding occurred during incision of the inferior vena cava or after removal of tumor thrombus. The follow-up period ranged from 3 to 20 months with a mean of 12.6 months. Of the five patients, three died of metastatic diseases, one died of liver dysfunction and one remains disease free as of 18 months postoperatively. Conclusions:, Our experience indicates that this procedure can be safely used for atrial involvement. Although superior long-term survival cannot be shown yet, favorable early results and a lack of perioperative complications were identified. [source]


    Thrombotic thrombocytopenic purpura: Results of the patients with thrombotic microangiopathies across Japan by ADAMTS13 analysis during 1998,2008

    ISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n2 2009
    Y. Fujimura
    Background, Thrombotic microangiopathies (TMAs) are pathological conditions, characterized by generalized microvascular occlusion by platelet thrombi, thrombocytopenia, and microangiopathic hemolytic anemia. Two typical phenotypes of TMAs are hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP). Severe deficiency of plasma ADAMTS13 activity (ADAMTS13:AC) is more specific for TTP but not for HUS. Materials & Methods, Since 1998, our laboratory has functioned as a nationwide referral center for TMAs by analyzing ADAMTS13. Of 1564 tested patients from 426 hospitals, 919 were positive for TMAs. Levels of ADAMTS13:AC and the ADAMTS13-neutralizing autoantibodies (ADAMTS13:INH) in these patients were determined by chromogenic act-ELISA and/or by classic von Willebrand factor multimer assay. Results, TMA patients consisted of two groups, those with severe (less than 3% of normal control) and those with non-severe deficiency of ADAMTS13:AC. Additionally, both groups were divided into congenital (n = 65) and acquired (n = 854) TMAs. Of the congenital TMA patients, 41 had ADAMTS13:AC deficiency due to gene mutations, while the remaining 24 had the disease of unknown etiology. The 854 patients with acquired TMAs could be largely grouped into three categories: idiopathic TTP (n = 284), idiopathic HUS (n = 106), and secondary TMAs (n = 464). The secondary TMAs were observed in heterogeneous patient groups and were associated with drugs, connective tissue diseases, malignancies, transplantation, pregnancy, E. coli O157:H7 infection, and other factors. All of the patients with acquired severe ADAMTS13:AC deficiency were positive for ADAMTS13:INH. Conclusion, Although TMAs are highly heterogeneous pathological conditions, one third of TMA patients have severe deficiency of ADAMTS13:AC. Platelet transfusions to such patients are contraindicated. Thus, rapid ADAMTS13:AC assays will be prerequisite in medical facilities where TMA patients are treated. [source]


    Periprocedural Anticoagulation for Atrial Fibrillation Ablation

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2008
    M. EYMAN MORTADA M.D.
    Background: Catheter ablation for atrial fibrillation (AF) can increase risk of left atrial (LA) thrombi and stroke. Optimal periprocedural anticoagulation has not been determined. Objective: We report the role of administering warfarin and aspirin without low molecular weight heparin in patients undergoing AF ablation. Methods: A total of 207 patients underwent ablation for AF. Transesophageal echocardiography (TEE) guided transseptal puncture and ruled out clot in the LA. After first puncture, the sheath was flushed with heparin (5,000 Units/mL). After second puncture, a bolus of 80 units/kg of heparin was given, followed by an infusion to maintain activated clotting time (ACT) around 300,350 seconds. Warfarin was stopped and aspirin was started (325 mg/day) 3 days preprocedure. Warfarin was restarted on the day of the procedure. Both medications were continued for 6 weeks postablation. Warfarin was continued for 6 months in patients with prior history of persistent or recurrent AF. Thirty-seven patients who showed smoke in the LA on TEE were given low molecular weight heparin postprocedure until international normalized ratio (INR) was therapeutic. Results: Thirty-two patients had persistent and 175 had paroxysmal AF; 87 were cardioverted during ablation. Two patients had transient ischemic attack (TIA) on the sixth and eighth days, respectively, following ablation, with complete recovery. Both had subtherapeutic INRs. Conclusion: In patients without demonstrable clot or smoke in the LA, starting aspirin 3 days prior and warfarin immediately post-radiofrequency ablation, without low molecular weight heparin, with meticulous anticoagulation during the procedure, appears to be a safe mode of anticoagulation. [source]


    Effect of blood group on idiopathic thrombotic thrombocytopenic purpura

    JOURNAL OF CLINICAL APHERESIS, Issue 4 2009
    Lara Zuberi
    Abstract Thrombotic thrombocytopenic purpura (TTP) is a condition caused by deficiency of ADAMTS13 resulting in accumulation of ultra large Von Willebrand factor multimers (ULVWF), leading to micro thrombi in multiple organs. The varying susceptibilities of blood group antigens to ADAMTS13 have been demonstrated. A and B antigens are protective of VWF; and VWF purified from blood group O individuals has been shown to be cleaved faster by ADAMTS13 compared to VWF from blood group AB individuals. We proposed that there may be a difference in the incidence of blood groups in TTP patients compared with the general population. We felt this to be important for a life-threatening disease with poorly understood epidemiology. We report a retrospective analysis of 74 patients presenting from 1993 to 2008 with idiopathic TTP. We studied the incidence across various blood groups and also estimated the recurrence and mortality in each group. The incidence of various blood groups were as follows: O 36%, A 36%, B 25%, and AB 2%, compared with expected frequencies in the Detroit area: O 44%, A 33% B 20%, and AB 3%. There was a trend of lower than expected frequency of blood group O. There were 24 recurrences and 14 deaths, uniform across blood groups. We hypothesized that there may be an association between blood groups and the risk of TTP; however the differences in our study were not statistically significant. Recurrence and disease specific mortality did not appear to be impacted by blood group. J. Clin. Apheresis 2009. © 2009 Wiley-Liss, Inc. [source]


    Asymptomatic deep vein thrombosis in advanced cancer patients: The value of venous sonography

    JOURNAL OF CLINICAL ULTRASOUND, Issue 5 2010
    Nira Beck-Razi MD
    Abstract Purpose. Although guidelines for venous thromboembolism prevention are available, the implementation of anticoagulant prophylaxis in patients with advanced cancer has yet to be more clearly defined. We aim to determine the incidence of lower extremity deep vein thrombosis (DVT) diagnosed by Doppler sonography (USD) in asymptomatic nonambulatory patients with advanced cancer. Method. In a prospective study, 44 nonambulatory cancer patients with grade 3,4 World Health Organization performance status, asymptomatic for lower extremity DVT, underwent bilateral venous USD studies of the lower extremities. Different risk factors and laboratory data were registered and correlated with the incidence of DVT. Result. Asymptomatic DVT was detected in 15 of 44 patients (34%, 95% CI, 0.21,0.49). Twenty-three percent of all patients had isolated deep calf vein thrombi and 11% of all patients had thrombi in the proximal veins. The only significant risk factor was the number of metastatic sites. DVT was found in 4 of 23 (17.4%) patients with one metastatic site as opposed to 11 of 21 (52.3%) with two or more sites (p < 0.01). Conclusion. USD of the lower extremities detected asymptomatic DVT in 34% of advanced nonambulatory cancer patients and may serve as an additional decision-making tool in the consideration of anticoagulant therapy for this specific population. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source]


    Serial compression B-scan and Doppler sonography for the screening of deep venous thrombosis in patients with spinal cord injuries

    JOURNAL OF CLINICAL ULTRASOUND, Issue 1 2010
    Alfried Germing MD
    Abstract Purpose To evaluate the usefulness of serial compression B-scan and Doppler sonography (US) in screening for deep venous thrombosis (DVT) of the lower extremities in patients with spinal cord injuries. Method Patients with paraplegia and tetraplegia due to spinal cord injuries were screened by a serial compression B-scan and Doppler US protocol for DVT of the bilateral lower extremities within the first 36 hours after admission, at day 7 and at day 21. In patients with DVT, a follow-up US examination was performed 3 weeks after diagnosis to assess thrombi distribution. Results Between January 2007 and March 2008, a total of 115 patients (75 males, 40 females), aged 19 to 85 years, were included. The first US examination documented a DVT in 44 cases (38.3%). After an initial negative scan, sonography after 7 days and 21 days showed DVT in 6 patients and 2 patients, respectively. Cumulative rate of DVT after the first 3 weeks was 45.2% (n=52). Follow-up US after 3 weeks in patients with DVT documented a complete recanalization in 19 patients (36.5%), no change in 12 patients (23.1%), and residual thrombi with partial recanalization in 21 patients (40.4%). Conclusion Our study supports the use of serial compression B-scan and Doppler US as a screening tool for DVT of the lower extremities in patients with spinal cord injuries early after injury. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source]


    Intravascular histiocytosis presenting with extensive vulvar necrosis

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 2009
    Pedram Pouryazdanparast
    Intravascular histiocytosis (IVH) is a rare reactive cutaneous lesion of unknown pathogenesis. Most cases are reported in association with rheumatoid arthritis, and cutaneous eruptions typically occur near swollen joints. The skin changes have included erythematous and violaceous macules, papules, plaques and indurated patches with a livedo-like pattern of erythema. We report the first case of IVH presenting with florid vulvar necrosis in an 87-year-old patient without a history of rheumatoid arthritis. Physical examination revealed an edematous, exudative and diffusely necrotic vulva with erythema surrounding the areas of necrosis, extending out to the thighs. The debrided skin revealed an extensively necrotic epidermis and multiple clusters of markedly dilated blood vessels within the dermis. These vessels contained fibrin thrombi admixed with numerous CD68+ and CD163+ histiocytes. Her skin changes improved significantly after surgical debridement and treatment with antibiotics. Interestingly, our patient was also found to have a lupus anticoagulant with elevated anticardiolipin antibodies. This is the first report of IVH possibly related to a thrombogenic diathesis associated with a hypercoagulable state. A diagnosis of IVH is important and may necessitate further clinical evaluation to exclude the possibility of co-existent systemic disease. [source]


    Can Renal Acute Tubular Necrosis Be Differentiated from Autolysis at Autopsy?,

    JOURNAL OF FORENSIC SCIENCES, Issue 2 2009
    Linda Kocovski B.Sc.
    Abstract:, We investigate the morphological characteristics that may differentiate between ischemic acute tubular necrosis (ATN) and autolysis in postmortem samples. Renal tissue from 57 postmortem cases with an antemortem diagnosis of ATN and 57 age-/sex-matched control cases were examined for 10 morphological characteristics: epithelial proliferation (Ki-67 immunoperoxidase positivity), fibrin thrombi, tubular epithelial whorls, mitoses, casts, autolysis, tubulorrhexis, epithelial flattening, interstitial inflammation, and interstitial expansion. Tubular epithelial whorls were found in 16 ATN cases and were absent in controls. These findings suggest that specific morphological criteria may distinguish ischemic ATN from autolysis. Diagnoses of ATN may be confirmed using these combined criteria as contributing to cause of death and/or to ascertain previously undiagnosed cases of ATN postmortem. [source]


    The Rationale for and Comparisons of Different Antiplatelet Treatments in Acute Coronary Syndrome

    JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 2008
    PAUL A. GURBEL M.D.
    Fundamentally, acute coronary syndromes are platelet-centric diseases, resulting from platelet-rich thrombi that develop at the site of vessel wall injury. In addition to aggregation, platelets modulate a plethora of other important pathophysiologic processes, including inflammation and coagulation. Therefore, a primary goal of therapy in the acute setting should be treatment with agents that provide predictable and superior platelet inhibition to prevent further ischemic events that develop from unchecked high platelet reactivity. Translational research studies of patients undergoing percutaneous revascularization have clearly demonstrated that adverse thrombotic outcomes are associated with high platelet reactivity and the latter is now emerging as a potent measurable cardiovascular risk factor. The intensity of antithrombotic therapy is influenced by patient risk. In the highest risk patients with elevated cardiac biomarkers indicative of myonecrosis, current guidelines support the use of early therapy with glycoprotein IIb/IIIa inhibition, aspirin, and clopidogrel. [source]


    Pathology of the Thin-Cap Fibroatheroma:

    JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2003
    A Type of Vulnerable Plaque
    Thin cap atheroma is the precursor of plaque rupture, which accounts for a majority of coronary thrombi. The morphologic features of thin cap atheromas that predict rupture are unknown, but we know from studies of ruptured plaques that large necrotic cores, fibrous cap <65 microns and numerous macrophages within the cap likely indicate instability. There is some evidence that a speckled pattern of calcification is associated with vulnerability to rupture. There are usually multiple thin cap atheroma in the hearts of patients dying with acute plaque rupture, as well as multiple fibroatheromas with intraplaque hemorrhage. Targeted therapy for the purpose of stabilizing coronary lesions that are prone to rupture is a major future goal of the interventionist. (J Interven Cardiol 2003;16:267,272) [source]


    Effect of the small molecule plasminogen activator inhibitor-1 (PAI-1) inhibitor, PAI-749, in clinical models of fibrinolysis

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2010
    A. J. LUCKING
    Summary.,Background:,The principal inhibitor of fibrinolysis in vivo is plasminogen activator inhibitor-1 (PAI-1). PAI-749 is a small molecule inhibitor of PAI-1 with proven antithrombotic efficacy in several preclinical models. Objective:,To assess the effect of PAI-749, by using an established ex vivo clinical model of thrombosis and a range of complementary in vitro human plasma-based and whole blood-based models of fibrinolysis. Methods:,In a double-blind, randomized, crossover study, ex vivo thrombus formation was assessed using the Badimon chamber in 12 healthy volunteers during extracorporeal administration of tissue-type plasminogen activator (t-PA) in the presence of PAI-749 or control. t-PA-mediated lysis of plasma clots and of whole blood model thrombi were assessed in vitro. The role of vitronectin was examined by assessing lysis of fibrin clots generated from purified plasma proteins. Results:,There was a dose-dependent reduction in ex vivo thrombus formation by t-PA (P < 0.0001). PAI-749 had no effect on in vitro or ex vivo thrombus formation or fibrinolysis in the presence or absence of t-PA. Inhibition of PAI-1 with a blocking antibody enhanced fibrinolysis in vitro (P < 0.05). Conclusions: Despite its efficacy in a purified human system and in preclinical models of thrombosis, the current study suggests that PAI-749 does not affect thrombus formation or fibrinolysis in a range of established human plasma and whole blood-based systems. [source]


    A platelet tetraspanin superfamily member, CD151, is required for regulation of thrombus growth and stability in vivo

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2009
    E. ORLOWSKI
    Summary.,Background:,This study was designed to determine the role of CD151 in platelet thrombus formation in vivo and define the contribution of platelet vs. endothelial CD151 in regulating platelet thrombus formation in vivo. Methods and Results: Using intravital microscopy and ferric chloride (FeCl3) injury of mesenteric arterioles, we found that thrombi formed in CD151+/, and CD151,/, mice were smaller and less stable, than those formed in CD151+/+ mice, with a tendency for embolization. Similarly, in Folt's FeCl3,induced carotid injury model, both CD151+/, and CD151,/, mice showed more prolonged times to 95% vessel occlusion than CD151+/+ mice. In addition, laser-induced injury of cremaster muscle arterioles showed that thrombi formed in CD151+/, and CD151,/, mice were smaller and less stable than those formed in CD151+/+ mice. Following platelet depletion/reconstitution with ex vivo -labeled donor platelets, platelet-depleted CD151+/+ mice that received reconstitution with CD151,/, platelets had smaller thrombi that were unstable and embolized. In contrast, platelet-depleted CD151,/, mice that received reconstitution with CD151+/+ platelets had normal thrombi that were stable. Conclusions: These data provide evidence that platelet CD151 is required for regulating thrombus formation in vivo. [source]


    von Willebrand factor is a major determinant of ADAMTS-13 decrease during mouse sepsis induced by cecum ligation and puncture

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 5 2009
    N. LEROLLE
    Summary.,Background:,During sepsis, von Willebrand factor (VWF) is abundantly secreted; the main mechanism regulating its size involves specific proteolysis by the metalloprotease ADAMTS-13. Objectives:,To determine whether ADAMTS-13 consumption due to its binding to, and/or cleavage, of VWF contributes to its decrease during sepsis and whether abrogating or enhancing ADAMTS-13 activity influences sepsis outcome. Methods:,ADAMTS-13 activity was evaluated in a model of sepsis induced by cecum ligature and puncture (CLP) in wild-type and Vwf,/, mice. Sepsis outcome was studied in those mice and in Adamts-13,/, mice. Finally, survival was studied in wild-type mice injected hydrodynamically with the human ADAMTS-13 gene. Results:,In wild-type mice, CLP-induced sepsis elicited a significant ADAMTS-13 decrease, and a strong negative correlation existed between VWF and ADAMTS-13. In Vwf,/, mice, CLP also induced severe sepsis, but ADAMTS-13 was not significantly diminished. Notably, Vwf,/, mice lived significantly longer than wild-type mice. In contrast, Adamts-13,/, mice and wild-type mice were comparable with regard to thrombocytopenia, VWF concentrations, absence of thrombi, and survival. Hydrodynamic hADAMTS-13 gene transfer with the pLIVE expression vector resulted in high and stable ADAMTS13 activity in CLP mice; however, no impact on survival was observed. Conclusions: VWF secretion is a major determinant of ADAMTS-13 decrease in the CLP model, and plays an important role in sepsis-induced mortality, but the complete absence of its regulating protease, ADAMTS-13, had no detectable impact in this sepsis model. Furthermore, increasing ADAMTS-13 activity had no impact on survival. [source]


    Complementary roles of platelets and coagulation in thrombus formation on plaques acutely ruptured by targeted ultrasound treatment: a novel intravital model

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2009
    M. J. E. KUIJPERS
    Summary.,Background:,Atherothrombosis is a major cause of cardiovascular events. However, animal models to study this process are scarce. Objectives:,We describe the first murine model of acute thrombus formation upon plaque rupture to study atherothrombosis by intravital fluorescence microscopy. Methods:,Localized rupture of an atherosclerotic plaque in a carotid artery from Apoe,/, mice was induced in vivo using ultrasound. Rupture of the plaque and formation of localized thrombi were verified by two-photon laser scanning microscopy (TPLSM) in isolated arteries, and by immunohistochemistry. The thrombotic reaction was quantified by intravital fluorescence microscopy. Results:,Inspection of the ultrasound-treated plaques by histochemistry and TPLSM demonstrated local damage, collagen exposure, luminal thrombus formation as well as intra-plaque intrusion of erythrocytes and fibrin. Ultrasound treatment of healthy carotid arteries resulted in endothelial damage and limited platelet adhesion. Real-time intravital fluorescence microscopy demonstrated rapid platelet deposition on plaques and formation of a single thrombus that remained subocclusive. The thrombotic process was antagonized by thrombin inhibition, or by blocking of collagen or adenosine diphosphate receptor pathways. Multiple thrombi were formed in 70% of mice lacking CD40L. Conclusions:,Targeted rupture of murine plaques results in collagen exposure and non-occlusive thrombus formation. The thrombotic process relies on platelet activation as well as on thrombin generation and coagulation, and is sensitive to established and novel antithrombotic medication. This model provides new possibilities to study atherothrombosis in vivo. [source]


    Circulating tissue factor accumulates in thrombi, but not in hemostatic plugs

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 9 2006
    M. HOFFMAN
    No abstract is available for this article. [source]


    The utility of quantitative calf muscle near-infrared spectroscopy in the follow-up of acute deep vein thrombosis

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2006
    T. YAMAKI
    Summary.,Background:,To investigate patterns of venous insufficiency and changes in calf muscle deoxygenated hemoglobin (HHb) levels after an acute deep vein thrombosis (DVT). Methods:,A total of 78 limbs with an acute DVT involving 156 anatomic segments were evaluated with duplex scanning and near-infrared spectroscopy (NIRS) at 1, 3, 6 and 12 months. Venous segments were examined whether they were occluded, partially recanalized, and totally recanalized, and the development of venous reflux was noted. The NIRS was used to measure calf muscle HHb levels. Calf venous blood filling index (HHbFI) was calculated on standing, then the calf venous ejection index (HHbEI), and the venous retention index (HHbRI) were obtained after exercise. Results:,The segments investigated were the common femoral vein (CFV; 38 segments), femoral vein (FV; 37), popliteal vein (POPV; 44), and calf veins (CV; 37). At 1 year, thrombi had fully resolved in 67% of the segments, 27% remained partially recanalized, 6% were occluded. The venous occlusion was predominant in the FV (24%) at 1 year. On the contrary, rapid recanalization was obtained in CV than proximal veins at each examination (P < 0.01). Venous reflux was predominant in POPV (55%), followed by FV (19%), and no reflux was found in CV. At 1 year, the HHbFI in POPV reflux patients was significantly higher than those with resolution (0.19 ± 0.14, 0.11 ± 0.05 ,m s, P = 0.009, respectively). Similarly, there was a significant difference in the HHbRI between the two groups (3.08 ± 1.91, 1.42 ± 1.56, P = 0.002, respectively). In patients with FV occlusion, the value of HHbRI was significantly higher than those with complete resolution (2.59 ± 1.50, 1.42 ± 1.56, P = 0.011, respectively). Conclusions:,The lower extremity venous segments show different proportions of occlusion, partial recanalization, and total recanalization. The CV shows more rapid recanalization than proximal veins. The NIRS-derived HHbFI and HHbRI could be promising parameters as the overall venous function in the follow-up of acute DVT. These findings might be very helpful for physician in detecting patients who require much longer follow-up studies. [source]


    Co-localization of von Willebrand factor with platelet thrombi, tissue factor and platelets with fibrin, and consistent presence of inflammatory cells in coronary thrombi obtained by an aspiration device from patients with acute myocardial infarction

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2006
    Y. HOSHIBA
    Summary.,Background:,Detailed histochemical analysis of coronary thrombi obtained freshly from acute phase of myocardial infarction patients may provide information necessary to understand the mechanism of coronary occlusive thrombus formation. Methods and Results:,Coronary thrombi causing myocardial infarction were obtained from 10 consecutive patients of myocardial infarction in the acute phase, using a newly developed aspiration catheter. All the fixed specimens of coronary thrombi, by hematoxylin and eosin staining, were found to contain three major constituents, namely, platelets, densely packed fibrin and inflammatory cells, including polymorphonuclear and mononuclear cells, although their distribution in each specimen is totally heterogeneous. Immunohistochemical staining revealed the prominent presence of von Willebrand factor (VWF) at the sites of platelet accumulation, presence of tissue factor and platelets at the sites of deposition of fibrin fibrils. It also revealed the presence of CD16-, CD45- and CD34-positive cells, yet the functional roles of these cells have still to be elucidated. There are weak positive correlation between the number of inflammatory cells involved in the unit area of coronary thrombi specimen and the time of collection of the specimens after the onset of chest pain. Conclusions:,In spite of various limitations, our results contain information suggesting the possible role of VWF in platelet-thrombus formation, possible important role played by tissue factor and activated platelets in the formation of fibrin fibrils, and the positive relationship between inflammatory cells migration and the formation of occlusive thrombi in human coronary arteries. [source]