RESUMO
BACKGROUND: Subclinical leaflet thickening and reduced leaflet motion of bioprosthetic aortic valves have been documented by four-dimensional computed tomography (CT). Whether anticoagulation can reduce these phenomena after transcatheter aortic-valve replacement (TAVR) is not known. METHODS: In a substudy of a large randomized trial, we randomly assigned patients who had undergone successful TAVR and who did not have an indication for long-term anticoagulation to a rivaroxaban-based antithrombotic strategy (rivaroxaban [10 mg] plus aspirin [75 to 100 mg] once daily) or an antiplatelet-based strategy (clopidogrel [75 mg] plus aspirin [75 to 100 mg] once daily). Patients underwent evaluation by four-dimensional CT at a mean (±SD) of 90±15 days after randomization. The primary end point was the percentage of patients with at least one prosthetic valve leaflet with grade 3 or higher motion reduction (i.e., involving >50% of the leaflet). Leaflet thickening was also assessed. RESULTS: A total of 231 patients were enrolled. At least one prosthetic valve leaflet with grade 3 or higher motion reduction was found in 2 of 97 patients (2.1%) who had scans that could be evaluated in the rivaroxaban group, as compared with 11 of 101 (10.9%) in the antiplatelet group (difference, -8.8 percentage points; 95% confidence interval [CI], -16.5 to -1.9; P = 0.01). Thickening of at least one leaflet was observed in 12 of 97 patients (12.4%) in the rivaroxaban group and in 33 of 102 (32.4%) in the antiplatelet group (difference, -20.0 percentage points; 95% CI, -30.9 to -8.5). In the main trial, the risk of death or thromboembolic events and the risk of life-threatening, disabling, or major bleeding were higher with rivaroxaban (hazard ratios of 1.35 and 1.50, respectively). CONCLUSIONS: In a substudy of a trial involving patients without an indication for long-term anticoagulation who had undergone successful TAVR, a rivaroxaban-based antithrombotic strategy was more effective than an antiplatelet-based strategy in preventing subclinical leaflet-motion abnormalities. However, in the main trial, the rivaroxaban-based strategy was associated with a higher risk of death or thromboembolic complications and a higher risk of bleeding than the antiplatelet-based strategy. (Funded by Bayer; GALILEO-4D ClinicalTrials.gov number, NCT02833948.).
Assuntos
Valva Aórtica/fisiopatologia , Aspirina/farmacologia , Clopidogrel/farmacologia , Inibidores do Fator Xa/farmacologia , Próteses Valvulares Cardíacas , Inibidores da Agregação Plaquetária/farmacologia , Rivaroxabana/farmacologia , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/efeitos dos fármacos , Valva Aórtica/patologia , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Clopidogrel/efeitos adversos , Clopidogrel/uso terapêutico , Quimioterapia Combinada , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Feminino , Tomografia Computadorizada Quadridimensional , Hemorragia/induzido quimicamente , Humanos , Análise de Intenção de Tratamento , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Rivaroxabana/efeitos adversos , Rivaroxabana/uso terapêutico , Tromboembolia/etiologia , Tromboembolia/mortalidadeRESUMO
BACKGROUND: Whether the direct factor Xa inhibitor rivaroxaban can prevent thromboembolic events after transcatheter aortic-valve replacement (TAVR) is unclear. METHODS: We randomly assigned 1644 patients without an established indication for oral anticoagulation after successful TAVR to receive rivaroxaban at a dose of 10 mg daily (with aspirin at a dose of 75 to 100 mg daily for the first 3 months) (rivaroxaban group) or aspirin at a dose of 75 to 100 mg daily (with clopidogrel at a dose of 75 mg daily for the first 3 months) (antiplatelet group). The primary efficacy outcome was the composite of death or thromboembolic events. The primary safety outcome was major, disabling, or life-threatening bleeding. The trial was terminated prematurely by the data and safety monitoring board because of safety concerns. RESULTS: After a median of 17 months, death or a first thromboembolic event (intention-to-treat analysis) had occurred in 105 patients in the rivaroxaban group and in 78 patients in the antiplatelet group (incidence rates, 9.8 and 7.2 per 100 person-years, respectively; hazard ratio with rivaroxaban, 1.35; 95% confidence interval [CI], 1.01 to 1.81; P = 0.04). Major, disabling, or life-threatening bleeding (intention-to-treat analysis) had occurred in 46 and 31 patients, respectively (4.3 and 2.8 per 100 person-years; hazard ratio, 1.50; 95% CI, 0.95 to 2.37; P = 0.08). A total of 64 deaths occurred in the rivaroxaban group and 38 in the antiplatelet group (5.8 and 3.4 per 100 person-years, respectively; hazard ratio, 1.69; 95% CI, 1.13 to 2.53). CONCLUSIONS: In patients without an established indication for oral anticoagulation after successful TAVR, a treatment strategy including rivaroxaban at a dose of 10 mg daily was associated with a higher risk of death or thromboembolic complications and a higher risk of bleeding than an antiplatelet-based strategy. (Funded by Bayer and Janssen Pharmaceuticals; GALILEO ClinicalTrials.gov number, NCT02556203.).
Assuntos
Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Rivaroxabana/uso terapêutico , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Aspirina/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Clopidogrel/efeitos adversos , Quimioterapia Combinada , Inibidores do Fator Xa/efeitos adversos , Feminino , Próteses Valvulares Cardíacas , Hemorragia/induzido quimicamente , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Rivaroxabana/efeitos adversos , Tromboembolia/mortalidadeRESUMO
BACKGROUND: Optimal antithrombotic treatment after transcatheter aortic valve replacement (TAVR) is unknown and determined empirically. The direct factor Xa inhibitor rivaroxaban may potentially reduce TAVR-related thrombotic complications and premature valve failure. DESIGN: GALILEO is an international, randomized, open-label, event-driven, phase III trial in more than 1,520 patients without an indication for oral anticoagulation who underwent a successful TAVR (ClinicalTrials.govNCT02556203). Patients are randomized (1:1 ratio), 1 to 7days after a successful TAVR, to either a rivaroxaban-based strategy or an antiplatelet-based strategy. In the experimental arm, subjects receive rivaroxaban (10mg once daily [OD]) plus acetylsalicylic acid (ASA, 75-100mg OD) for 90days followed by rivaroxaban alone. In the control arm, subjects receive clopidogrel (75mg OD) plus ASA (as above) for 90days followed by ASA alone. In case new-onset atrial fibrillation occurs after randomization, full oral anticoagulation will be implemented with maintenance of the original treatment assignment. The primary efficacy end point is the composite of all-cause death, stroke, myocardial infarction, symptomatic valve thrombosis, pulmonary embolism, deep venous thrombosis, and systemic embolism. The primary safety end point is the composite of life-threatening, disabling, and major bleeding, according to the Valve Academic Research Consortium definitions. CONCLUSIONS: GALILEO will test the hypothesis that a rivaroxaban-based antithrombotic strategy reduces the risk of thromboembolic complications post-TAVR with an acceptable risk of bleeding compared with the currently recommended antiplatelet therapy-based strategy in subjects without need of chronic oral anticoagulation.
Assuntos
Estenose da Valva Aórtica/cirurgia , Aspirina/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Inibidores do Fator Xa/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Rivaroxabana/uso terapêutico , Substituição da Valva Aórtica Transcateter , Doenças Cardiovasculares/epidemiologia , Causas de Morte , Clopidogrel , Quimioterapia Combinada , Embolia/epidemiologia , Embolia/prevenção & controle , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/prevenção & controle , Humanos , Mortalidade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Cuidados Pós-Operatórios/métodos , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Trombose/epidemiologia , Trombose/prevenção & controle , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Trombose Venosa/epidemiologia , Trombose Venosa/prevenção & controleRESUMO
BACKGROUND: Previous studies suggested that hypofibrinolysis is associated with increased risk of peripheral arterial disease. Thrombin activatable fibrinolysis inhibitor (TAFI) has been identified as an important inhibitor of fibrinolysis. The aim of our study was to assess the role of TAFI in young patients with peripheral arterial disease. METHODS: In a single-center case-control study we measured plasma TAFI antigen levels and functional TAFI in consecutive young patients (men 18-45 years and women 18-55 years) with a first manifestation of peripheral arterial disease and compared these with a population-based control group. RESULTS: A total of 47 peripheral arterial disease patients and 141 controls (mean age 43) were included. Intact TAFI antigen levels were significantly higher in patients with peripheral arterial disease (112.4±21.1%) than in controls (104.9±19.9%, p=0.03). The risk of peripheral arterial disease increased with 18% (OR 1.18; CI 1.01-1.34) per 10% increase of TAFI antigen. Functional TAFI levels were slightly higher in patients compared to controls, however this difference was not significant. For individuals with the highest functional TAFI levels, above the 90th percentile, the increased risk for peripheral arterial disease was most pronounced (OR 3.1; CI 1.02-9.41). CONCLUSION: High TAFI levels are associated with increased risk of premature peripheral arterial disease.
Assuntos
Carboxipeptidase B2/sangue , Doença Arterial Periférica/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Fibrinólise , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/epidemiologia , Fatores de Risco , Adulto JovemRESUMO
In Budd-Chiari syndrome (BCS), thrombosis develops in the hepatic veins or inferior vena cava. To study the relationship between hypofibrinolysis and BCS, we measured plasma levels of fibrinolysis proteins in 101 BCS patients and 101 healthy controls and performed a plasma-based clot lysis assay. In BCS patients, plasminogen activator inhibitor 1 (PAI-1) levels were significantly higher than in controls (median, 6.3 vs 1.4 IU/mL, P < .001). Thrombin-activatable fibrinolysis inhibitor and plasmin inhibitor levels were lower than in controls (13.8 vs 16.9 microg/mL and 0.91 vs 1.02 U/L, both P < .001). Median plasma clot lysis time (CLT) was 73.9 minutes in cases and 73.0 minutes in controls (P = .329). A subgroup of cases displayed clearly elevated CLTs. A CLT above the 90th or 95th percentile of controls was associated with an increased risk of BCS, with odds ratios of 2.4 (95% confidence interval, 1.1-5.5) and 3.4 (95% confidence interval, 1.2-9.7), respectively. In controls, only PAI-1 activity was significantly associated with CLT. Analysis of single nucleotide polymorphisms of fibrinolysis proteins revealed no significant differences between cases and controls. This case-control study provides the first evidence that an impaired fibrinolytic potential, at least partially caused by elevated PAI-1 levels, is related to the presence of BCS.
Assuntos
Antifibrinolíticos/sangue , Síndrome de Budd-Chiari/sangue , Carboxipeptidase B2/sangue , Fibrinólise , Inibidor 1 de Ativador de Plasminogênio/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea/métodos , Síndrome de Budd-Chiari/genética , Carboxipeptidase B2/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/genética , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Risco , Veia Cava Inferior/metabolismoRESUMO
The relationship between defective fibrinolysis and arterial thrombosis is uncertain. The evaluation of the plasma fibrinolytic potential might provide stronger evidence linking fibrinolysis to arterial thrombosis than the evaluation of the individual fibrinolytic factors. We determined the plasma fibrinolytic potential of 335 young survivors of a first arterial thrombosis, including coronary artery disease (n = 198), ischaemic stroke (n = 103) and peripheral artery disease (n = 34), enrolled in a population-based case-control study and of 330 healthy individuals. Patients had significantly higher clot lysis times (CLTs) than the controls. Odds ratios (ORs) were calculated as a measure of relative risk. The OR for arterial thrombosis was determined in these subjects who had a CLT above the 60th, 70th, 80th, 90th and 95th percentiles of the values found in the control subjects. We found a progressive increase in risk of arterial thrombosis in subjects with hypofibrinolysis (OR: 1.7, 2.0, 2.3, 2.3 and 2.9, respectively). Relative risk estimates obtained in the whole group were comparable those obtained in the event-subgroups. In conclusion, a low plasma fibrinolytic potential, found in 10% of the population, increases the relative risk of arterial thrombosis twofold. This points to an important contribution of hypofibrinolysis to the burden of arterial thrombosis.
Assuntos
Fibrinólise/fisiologia , Trombose/sangue , Adulto , Índice de Massa Corporal , Isquemia Encefálica/sangue , Isquemia Encefálica/fisiopatologia , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/fisiopatologia , Feminino , Fibrinólise/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doenças Vasculares Periféricas/sangue , Doenças Vasculares Periféricas/fisiopatologia , Risco , Trombose/fisiopatologia , Ativador de Plasminogênio Tecidual , Adulto JovemRESUMO
OBJECTIVE: Besides having a key role in fibrinolysis, the plasminogen system has been implicated in cell migration and angiogenesis. A common mechanism is the binding of plasminogen to carboxy-terminal lysine residues in partially degraded fibrin or on cellular surfaces. Here we examined the involvement of thrombin activatable fibrinolysis inhibitor (TAFI) and pancreatic carboxypeptidase B (CPB) in an in vitro capillary tube formation system, which is largely plasminogen-dependent. METHODS AND RESULTS: Human microvascular endothelial cells (hMVECs) were seeded on a 3D plasma clot matrix and subsequently stimulated with bFGF/tumor necrosis factor (TNF)-alpha. Tube formation was analyzed and fibrin degradation products (FbDP) were determined in the medium. Supplementation of the matrix with additional TAFI or CPB produced a reduction in tube formation. Pretreatment of hMVECs with CPB before seeding resulted in a similar effect. FbDP-levels indicated a concomitant reduction in matrix proteolysis. A TAFIa inhibitor increased tube formation and FbDP release into the medium. In separate assays, CPB impaired the migration of hMVECs in a dose-dependent manner, whereas proliferation and adhesion remained unaffected. CONCLUSIONS: Overall, these results demonstrate that TAFI and CPB in these systems modulate the plasminogen system both in the matrix and on the cell surface, thus leading to the inhibition of endothelial cell movement and tube formation.
Assuntos
Inibidores da Angiogênese/metabolismo , Carboxipeptidase B2/metabolismo , Carboxipeptidase B/metabolismo , Movimento Celular , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Inibidores da Angiogênese/farmacologia , Aterosclerose/enzimologia , Capilares/citologia , Carboxipeptidase B/farmacologia , Carboxipeptidase B2/antagonistas & inibidores , Adesão Celular , Técnicas de Cultura de Células , Movimento Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Fibrina/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Plasminogênio/metabolismo , Inibidores de Proteases/farmacologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , CicatrizaçãoRESUMO
In this study, the in-vitro fibrinolytic efficacy of Tenecteplase, Amediplase and scu-PA was investigated in different external lysis models by measuring the lysis of human plasma clots after the addition of the plasminogen activators (PAs) to the surrounding plasma. The effect of TAFI was examined for each PA by neutralising TAFIa with potato carboxypeptidase inhibitor (PCI). The lytic efficacy of Amediplase was lower than that of Tenecteplase at low PA concentrations but slightly higher at therapeutic concentrations. The activity of scu-PA was clearly lower than that of either Tenecteplase or Amediplase. The TAFI system inhibited external clot lysis mediated by all the PAs when thrombomodulin was present in the model. In the therapeutic range (5-10 mug/ml) however, the TAFIa effect was negligible for both Amediplase and Tenecteplase. At lower PA concentrations the effect of TAFI on Amediplase was slightly stronger than that on Tenecteplase. Under static conditions the lysis rates were lower than with stirring. The role of TAFI was similar under both conditions. In conclusion, at therapeutic concentrations Amediplase was slightly more active than Tenecteplase and scu-PA under all conditions used. Therefore, Amediplase might possibly be a more potent thrombolytic agent at these concentrations and increase the efficacy of thrombolysis. The potential of TAFI for inhibiting thrombolytic therapy is probably low. However in conditions where the local PA concentrations are sub-optimal TAFI might affect the lysis rate.
Assuntos
Testes de Coagulação Sanguínea , Carboxipeptidase B2/farmacologia , Ativador de Plasminogênio Tecidual/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Coagulação Sanguínea , Carboxipeptidases/antagonistas & inibidores , Fibrina/química , Fibrinolíticos/farmacologia , Humanos , Ativadores de Plasminogênio , Proteínas Recombinantes , Sensibilidade e Especificidade , Solanum tuberosum , Tenecteplase , Fatores de Tempo , Ativador de Plasminogênio Tipo Uroquinase/farmacologiaRESUMO
TAFIa was shown to attenuate fibrinolysis. In our in vitro study, we investigated how the inhibitory effect of TAFIa depended on the type and concentration of the plasminogen activator (PA). We measured PA-mediated lysis times of plasma clots under conditions of maximal TAFI activation by thrombin-thrombo-modulin in the absence and presence of potato carboxypeptidase inhibitor. Seven different PAs were compared comprising both tPA-related (tPA, TNK-tPA, DSPA), bacterial PA-related (staphylokinase and APSAC) and urokinase-related (tcu-PA and k2tu-PA) PAs. The lysis times and the retardation factor were plotted against the PA concentration. The retardation factor plots were bell-shaped. At low PA concentrations, the retardation factor was low, probably due to the limited stability of TAFIa. At intermediate PA concentrations the retardation factor was maximal (3-6 depending on the PA), with TNK-tPA, APSAC and DSPA exhibiting the strongest effect. At high PA concentrations, the retardation factor was again low, possibly due to inactivation of TAFIa by plasmin or to a complete conversion of glu-plasminogen into lys-plasminogen. Using individual plasmas with a reduced plasmin inhibitor activity (plasmin inhibitor Enschede) the bell-shaped curve of the retardation factor shifted towards lower tPA and DSPA concentrations, but the height did not decrease. In conclusion, TAFIa delays the lysis of plasma clots mediated by all the plasminogen activators tested. This delay is dependent on the type and concentration of the plasminogen activator, but not on the fibrin specificity of the plasminogen activator. Furthermore, plasmin inhibitor does not play a significant role in the inhibition of plasma clot lysis by TAFI.