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ObjectivesThe aim of this study was to report 1-year clinical outcomes following commercial transcatheter left atrial appendage occlusion (LAAO) in the United States.BackgroundThe National Cardiovascular Data Registry LAAO Registry was initiated to meet a condition of Medicare coverage and allow the assessment of clinical outcomes. The 1-year rates of thromboembolic events after transcatheter LAAO in such a large cohort of “real-world” patients have not been previously reported.MethodsPatients entered into the National Cardiovascular Data Registry LAAO Registry for a Watchman procedure between January 1, 2016, and December 31, 2018, were included. The primary endpoint was ischemic stroke. Key secondary endpoints included the rate of ischemic stroke or systemic embolism, mortality, and major bleeding. Major bleeding was defined as any bleeding requiring hospitalization, and/or causing a decrease in hemoglobin level > 2g/dL, and/or requiring blood transfusion that was not hemorrhagic stroke. The Kaplan-Meier method was used for 1-year estimates of cumulative event rates.ResultsThe study population consisted of 36,681 patients. The mean age was 76.0 ± 8.1 years, the mean CHA2DS2-VASc score was 4.8 ± 1.5, and the mean HAS-BLED score was 3.0 ± 1.1. Prior stroke was present in 25.5%, clinically relevant bleeding in 69.5%, and intracranial bleeding in 11.9%. Median follow-up was 374 days (IQR: 212-425 days). The Kaplan-Meier–estimated 1-year rate of ischemic stroke was 1.53% (95% CI: 1.39%-1.69%), the rate of ischemic stroke or systemic embolism was 2.19% (95% CI: 2.01%-2.38%), and the rate of mortality was 8.52% (95% CI: 8.19%-8.87%). The 1-year estimated rate of major bleeding was 6.93% (95% CI: 6.65%-7.21%). Most bleeding events occurred between discharge and 45 days following the procedure.ConclusionsThis study characterizes important outcomes in a national cohort of patients undergoing transcatheter LAAO in the United States. Clinicians and patients can integrate these data in shared decision making when considering this therapy.  相似文献   
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Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate. Three groups of animals were studied. Group 1 (n = 9) was treated with warfarin, Group 2 (n = 13) with LMWH and Group 3, received no anti-coagulant drugs. The median duration of xenograft function was 20 days (range 3-62 days), 18 days (range 5-109 days) and 15 days (range 4-53 days) in Groups 1 to 3 respectively. Anti-coagulation achieved the targeted international normalized prothrombin ratio (INR) and anti-factor Xa levels consistent with effective in vivo therapy yet, no significant impact on median xenograft function was observed. At rejection, a similar histology of thrombosis and ischemia was apparent in each group and the levels of fibrin deposition and platelet thrombi in rejected tissue was the same. Anti-coagulation with warfarin or LMWH did not have a significant impact on the onset of DXR and microvascular thrombosis. However, a role for specific anti-coagulant strategies to achieve long-term xenograft function cannot be excluded.  相似文献   
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Objective:To explore the effect of thrombolysis with anticoagulation treatment forearly stage of deep vein thrombosis of lower extremity.Methods:The clinical data of 10 patients at the early stage of deep vein thrombosis(DVT)in the lower extremuites treated by thrombolysis with anticoagulation and dispersion drugs were analyzed retrospectively.Results:The thrombolytic effect was significant.After treatment,the deep veins were recanalized without regurgitation in 75.3% of the patients.The total effective rate was 100%.Only three patients had hemorrhagic complication,but none of the patients died.Conclusion:Thrombolysis with anticoagulation treatment is an effective and safe method for DVT at the early stage.  相似文献   
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Long-term oral anticoagulation requires careful patient monitoring in order to optimize results and to limit hemorrhagic or thromboembolic complications of treatment. For this reason, any improvement in anticoagulant control and management can be expected to have far-reaching consequences in extending longevity and decreasing complications in anticoagulated patients after heart valve surgery. Because one attractive means of improving anticoagulant management is to give patients a share of the responsibility, a program was designed to encourage patients to take an active role in monitoring their own prothrombin time (PT) and managing their own oral anticoagulation. During the period from August 1986 to February 1992, 600 patients requiring long-term anticoagulation, mainly after heart valve replacement, were trained to measure their own PT at the Cardiac Rehabilitation Center (Herz-Krauslauf-Klinik, Bad Berleburg, Germany) and to manage their own therapy: 216 patients could be followed with regard to their self-determined prothrombin times. The results were within the target range in 83.1% of the PT determinations (n=12,306 measurements) taken by the patients themselves. Neither major bleeding nor thromboembolic complications were observed in 205 patient-years of self-monitoring of PT and self-management of oral anticoagulation.  相似文献   
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Summary Excessive bleeding frequently complicates the care of critically-ill patients. Except in the case of trauma or in patients with known coagulopathies (e.g., hemophilia), the bleeding is generally not directly related to the illness that results in admission to the intensive care unit. In general, the causes of the bleeding can be divided into 3 categories: consumptive coagulopathies (e.g., DIC), bleeding related to ``hepatic issues' (i.e., liver dysfunction, vitamin K deficiency), and iatrogenic causes. This review will discuss the more common causes of bleeding in the critically-ill patient and outline diagnostic and treatment approaches for these patients. New experimental data linking activation of the coagulation and inflammatory systems with the development of multisystem organ failure is briefly discussed. Received: 8 November 1996 Accepted: 18 November 1996  相似文献   
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There is a paucity of data regarding the use of direct thrombin inhibitors such as bivalirudin for children on extracorporeal life support (ECLS). We sought to compare the outcomes of children on ECLS anticoagulated with bivalirudin versus heparin. Patients transitioned from heparin to bivalirudin were treated as a separate group. A single‐institution, retrospective review of all consecutive children (neonate to 18 years) placed on ECLS in the cardiac or pediatric intensive care units was performed (June 2018‐December 2019). Data collected included demographics, anticoagulation strategy, number of circuit interventions, blood product use on ECLS, survival to decannulation, and survival to discharge. Fifty‐four children were placed on ECLS for a total of 56 runs. Demographics and venovenous versus venoarterial ECLS were similar. The bivalirudin group had longer median duration of support compared to the heparin group––11.0 days [IQR 6.2, 23.1] versus 3.3 days [2.1, 6.2], P < .001. Patients switched from heparin to bivalirudin had a similar duration of support (10.3 days [8.3, 18.3]) as those on bilvalirudin alone. However, there was no difference in red blood cell, fresh frozen plasma, or platelet transfusions. There was no difference in the number of circuit interventions, survival to decannulation or discharge. The freedom to first circuit intervention was longer with bivalirudin compared to heparin. Our data suggest that even with longer pediatric ECLS runs on bivalirudin, there were no differences in the outcomes between the heparin and bivalirudin groups, with longer freedom from first circuit intervention with bivalirudin. While this is the largest reported series comparing children on ECLS anticoagulated with heparin versus bivalirudin, larger studies are needed to determine the optimal anticoagulation strategy for this diverse and complicated group of children.  相似文献   
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在正常和DIC家兔或大鼠中证明,口服龙津后,体外血栓长度缩短,血栓重量减轻,全血凝块和纤维蛋白凝块溶解加速,KPTT延长,ELT缩短,t-PA活性增强(P<0.05)。以上资料提示龙津有抗凝和溶栓的双重作用。  相似文献   
10.
注射用苦碟子的抗凝与纤溶活性   总被引:9,自引:0,他引:9  
目的观察注射用苦碟子抗凝和纤溶激活作用。方法采用测定全血凝块重量、凝血时间、优球蛋白溶解时间、血浆复钙凝血时间和凝血酶原时间的方法,观察注射用苦碟子对内源性和外源性凝血途径以及纤溶系统的影响。结果注射用苦碟子对内源性凝血途径具有较强的抑制作用,能够增加纤溶系统的活性;小鼠静脉给予注射用苦碟子6、12 mg.kg-1与对照组相比可显著降低全血凝块重量;大鼠静脉给予注射用苦碟子3.6、7.2 mg.kg-1可显著延长凝血时间,静脉给予注射用苦碟子1.8、3.6、7.2 mg.kg-1可显著缩短优球蛋白溶解时间;注射用苦碟子质量浓度为1.25、2.55、g.L-1时可显著延长血浆复钙凝血时间,离体凝血酶原时间与对照组相比无显著性差异。结论注射用苦碟子具有较强的抗凝血作用和纤溶活性。  相似文献   
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