Increased tissue factor pathway inhibitor in patients with acute myocardial infarction

We examined hemostatic abnormalities in 23 patients with acute myocardial infarction (AMI), 10 with pulmonary embolism (PE), and 10 with deep vein thrombosis (DVT). At the onset of AMI, plasma levels of tissue-type plasminogen activator (t-PA), PA inhibitor-I (PAI-I), fibrin-D-dimer, thrombin-antithrombin complex (TAT), and plasmin-plasmin inhibitor complex (PPIC) were significantly increased. Both the plasma total TFPI and free-TFPI levels in the AMI patients were significantly higher than those in the healthy volunteers, PE patients, and DVT patients. There was no significant difference in total TFPI or free-TFPI among patients with PE, those with DVT, and healthy volunteers. One hour after percutaneous transluminal coronary angioplasty (PTCA) in the AMI group, the total TFPI level was further increased, and it was significantly reduced 24 hr after PTCA, to a level similar to that in healthy volunteers. Free-TFPI showed a pattern similar to that of total TFPI. The ratio of free-TFPI/total TFPI was highest 1 hr after PTCA. Increased TFPI in AMI patients might be released from ischemic tissues. Am. J. Hematol. 55:183–187, 1997. © 1997 Wiley-Liss, Inc.     

急性心肌梗死患者直接介入治疗后无再流与血浆组织因子及其途径抑制物的关系

目的 通过测定急性心肌梗死(AMI)患者直接经皮冠状动脉介入治疗(PCI)前后血浆组织因子(TF)、组织因子途径抑制物(TFPI)水平的变化,探讨TF、TFPI与无再流的关系.方法 选择2006年5月至2007年5月于我院急诊行PCI的AMI患者53例,用ELISA法检测患者PCI术前、术后即刻、术后24 h外周静脉血 TF、TFPI水平.比较其中无再流者与再灌流者不同时点TF、TFPI水平的变化.结果 PCI术前、术后即刻、术后24 h无再流组血浆TF、TFPI水平均明显高于再灌流组[TF(275.3±46.2)ng/L比(236.8±44.3)ng/L、(332.7±41.3) ng/L 比(282.3±38.7) ng/L、(315.5±47.8) ng/L 比(248.1±46.9) ng/L;TFPI(165.2±38.4) μg/L 比(128.5±18.7) μg/L、(176.3±36.8)μg/L 比(135.6±20.3) μg/L、(149.8±31.7) μg/L 比(118.7±19.2) μg/L;均P＜0.01];PCI术后即刻,丽组TF水平均较术前明显升高(P＜0.01);PCI术后24 h,无再流组TF水平仍高于术前水平(P＜0.05),再灌流组与术前比较无差异(P＞0.05);PCI前后两组TFPI水平均无明显变化(P＞0.05).结论 AMI患者直接PCI后无再流的发生与血浆,TF水平呈正相关,TF可激活外源性凝血途径,形成微血栓而导致无再流,而TFPI可阻止血栓形成而防治无再流的发生.     

Tissue factor/tissue factor pathway inhibitor system and long-term prognosis after acute myocardial infarction

The tissue factor and tissue factor pathway inhibitor (TFPI) system has been studied in the acute phase of coronary disease but its prognostic importance has been less well assessed. We evaluated its association with recurrent coronary events during long-term follow-up after a myocardial infarction. Methods: We studied 55 consecutive patients with the following criteria for inclusion: (1) first myocardial infarct; (2) aged < 70 years; (3) non-complicated infarct; (4) low risk effort-test. Blood samples were taken 60-80 days after infarction. Tissue factor, total and free-TFPI were measured. A 4-year follow-up was carried out. Death, unstable angina and new myocardial infarction were considered as poor prognosis. Results: There were no statistical differences in tissue factor/TFPI levels between patients and controls. Total-TFPI showed statistical correlation with total cholesterol (r = 0.59), triglycerides (r = 0.34), LDL-cholesterol (r = 40) and Lipoprotein(a) (r = 0.48). Patients with high levels of cholesterol, LDL-cholesterol and triglycerides showed elevated levels of total-TFPI with no differences in free-TFPI. During follow-up, 8 patients showed poor prognosis. There were no statistical associations between tissue factor/TFPI levels and prognosis. Conclusions: After acute myocardial infarction, we did not find any differences in the tissue factor/TFPI system between controls and patients. The tissue factor/TFPI system showed little value as a prognostic factor.     

Plasma tissue factor pathway inhibitor levels in patients with acute pancreatitis

Background  

In acute pancreatitis (AP), disorders of the coagulation-fibrinolysis system are closely related to the severity of the AP and to organ dysfunctions. We previously reported that plasma tissue factor (TF) levels were elevated in patients with AP, particularly in cases of alcoholic AP with pancreatic necrosis. Tissue factor pathway inhibitor (TFPI) is a key regulator of the extrinsic coagulation pathway, but plasma TFPI levels in AP have not yet been determined.     

Combined effects of irbesartan and carvedilol on expression of tissue factor and tissue factor pathway inhibitor in rats after myocardial infarction

The objective of this study was to investigate the effects of irbesartan, carvedilol, and irbesartan plus carvedilol on the expression of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) mRNA and protein in rat myocardium after myocardial infarction (MI). MI was induced in male Wistar rats by ligation of the anterior descending branch of the left coronary artery. Irbesartan at 50 mg/kg/day, carvedilol at 1 mg/kg/day, irbesartan plus carvedilol, or placebo was administered intragastrically; expression of TF and TFPI mRNA and protein was determined by RT-PCR and Western blot analysis. The relative left ventricle weights were lower in all three treatment groups than in the placebo group, with the lowest relative weight in the irbesartan plus carvedilol group (P < 0.001). The size of the infarcted area was lower in the carvedilol and the combined groups than in the placebo group (P < 0.001). The levels of expression of TF and TFPI mRNA and protein were lower in the combined group than in the placebo group or the carvedilol group (P < 0.001). Treatment with irbesartan plus carvedilol reduced the expression of TF and TFPI mRNA and protein after MI in rats, and combined treatment with both agents had greater effects than the single agents alone. These findings suggest that the beneficial effects of these drugs may include anticoagulation and that combined therapy with both agents is an option that should be evaluated further.     

急性心肌梗死发作期间组织因子途径变化的观察

目的：观察急性心肌梗死（AMI）发作期间组织因子途径的变化。方法：69列临床确诊的AMI患和30例健康中老年人（作对照）被纳入研究对象。血浆中的组织因子（TF）和组织因子途径抑制物（TFPI）的活性测定采用发色底物法,TF和TFPI抗原采用ELISA法。激活的凝血因子Ⅶa采用重组可溶性TF法。凝血因子Ⅶ促凝活性采用活性测定法。结果：与对照组相比,AMI患血浆中TF、TFPI的活性均显增加[分别为5．67（1．77－54．95）mU/ml vs2.36(1.13-6.42)mU/ml,P＜0．01;224．85（86．65－512．12）％vs 138．75（51．72－297．2）％,P＜0．01]。同时TF、TFPI的抗原、凝血因子Ⅶa的活性亦有明显升高,但凝血因子Ⅶ促凝活性无显变化。结论：AMI发作期间体内组织因子途径被启动,血液呈现高凝状态。     

Low-molecular-weight heparin in patients with acute ST-segment elevation myocardial infarction

One of the primary goals of physicians treating patients presenting to a hospital with acute ST-segment elevation myocardial infarction is to restore the flow of blood in the infarct-related artery as quickly as possible. Prompt and successful reperfusion limits the size of the myocardial infarction, reduces left ventricular dysfunction, and improves the patient's chance of survival. Approximately two thirds of patients with ST-segment elevation myocardial infarction do not present to a hospital capable of conducting urgent direct percutaneous coronary intervention or cardiac surgery when it is needed. They must receive pharmacological reperfusion therapy, a combination of fibrinolytic, antiplatelet, and anticoagulant drugs. Earlier and simpler administration of pharmacological reperfusion therapy could result in significantly improved outcomes. Fibrinolytic therapy, in combination with adjunctive antithrombin therapy that is simpler and quicker to administer (e.g., tenecteplase with enoxaparin), may be more efficacious and easier to use than regimens involving unfractionated heparin.     

高血压与急性心肌梗死患者金属蛋白酶组织抑制物的比较

目的比较高血压患者和急性心肌梗死患者胶原代谢水平。方法高血压患者34例、急性心肌梗死患者21例和对照者31例,常规测量血压、体重、身高,计算体重指数,抽取空腹静脉血,用酶联免疫吸附法检测金属蛋白酶组织抑制物-1(tissue inhibitor of matrix metalloproteinase-1,TIMP-1)。结果 TIMP-1血清浓度,高血压组为(49±21)μg／L,高于急性心肌梗死组为(7 5)μg／L和对照组(14±6)μg/L,差异有统计学意义(P<0．01),但急性心肌梗死组和对照组差异无统计学差异。结论高血压患者胶原合成水平较急性心肌梗死患者显著升高。     

Tissue factor and tissue factor pathway inhibitor levels in unstable angina patients during short-term low-molecular-weight heparin administration

High tissue factor (TF), tissue factor pathway inhibitor (TFPI) levels and a hypercoagulability state have been documented in unstable angina patients. We evaluated whether short-term enoxaparin administration (100 IU/kg b.i.d. for 3 d) reduces the high TF levels and the hypercoagulability state, and whether it influences the fibrinolytic system in 20 unstable angina patients. On d 3, we observed a significant reduction in TF levels both 1 h and 4 h after the morning injection (-25.6% and -21.7%; P < 0.001 respectively) in comparison with the base-line levels. Both 1 and 4 h after the morning injection on the d 3, TFPI levels significantly (P < 0.001) increased (+96.4%, +96.9% respectively) with respect to the base-line values. After enoxaparin administration, at all observation times, thrombin-antithrombin complexes and prothrombin fragment F1 + 2 levels were significantly (P < 0.001) lower with respect to base-line levels. We observed a slight but significant increase in tissue plasminogen activator antigen levels in preinjection samples, as well as 1 h and 4 h after enoxaparin administration, in comparison with the base-line values. This study provides evidence that low-molecular-weight heparin (LMWH) administration, in addition to a reduction of hypercoagulability and a mild fibrinolytic activation, is associated with decreased TF levels, so indicating a novel mechanism of interference of LMWH with the haemostatic system.     

The effect of leukocyte elastase on tissue factor pathway inhibitor.

Tissue factor pathway inhibitor (TFPI) is a multivalent Kunitz-type inhibitor that directly inhibits factor Xa and, in a factor Xa-dependent fashion, also inhibits the factor VIIa/tissue factor (TF) catalytic complex. The Kunitz-2 domain in TFPI is needed for the binding and inhibition of factor Xa, while the Kunitz-1 domain appears to be responsible for binding factor VIIa in a quaternary factor Xa-TFPI-factor VIIa/TF inhibitory complex. Human leukocyte elastase (HLE) proteolytically cleaves TFPI between threonine-87 and threonine-88 within the polypeptide that links the Kunitz-1 and Kunitz-2 domains in the TFPI molecule. HLE treatment not only affects the ability of TFPI to inhibit factor VIIa/TF, but also dramatically reduces its inhibition of factor Xa. Both purified HLE and stimulated neutrophils regenerate TF activity from a preformed factor Xa-TFPI-factor VIIa/TF inhibitory complex. Kinetic analysis suggests that HLE cleavage does not effect the affinity of the initial encounter interaction between factor Xa and TFPI, whereas it markedly reduces the affinity of the final factor Xa:TFPI complex with Ki (final) values for untreated and HLE-treated TFPI of 58 pmol/L and 4.4 nmol/L, respectively. Thus, an epitope in the amino-terminal region of TFPI or a conformation of the TFPI molecule that requires the presence of this region is needed in concert with the Kunitz-2 domain to produce optimal inhibition of factor Xa by TFPI.     

Plasma tissue factor and tissue factor pathway inhibitor levels in patients with disseminated intravascular coagulation

We measured the plasma levels of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with disseminated intravascular coagulation (DIC) to examine the relationship between TFPI and vascular endothelial cell injury. Plasma TF (273 ± 90 pg/ml) and TFPI (252 ± 125 ng/ml) levels were significantly increased in patients with DIC compared with non-DIC patients. Plasma TF antigen level was significantly increased in pre-DIC patients (285 ± 85 pg/ml), while the plasma TFPI level (152 ± 54 ng/ml) was not markedly increased in such a state. The plasma TF/TFPI ratio was high in the pre-DIC patients (2.10 ± 0.90), and low in the DIC patients (1.40 ± 0.87) and healthy volunteers (0.84 ± 0.26). There was no significant difference between the DIC patients with a good outcome and those with a poor outcome in terms of plasma TF levels, although the plasma TFPI level in the DIC patients with a good outcome (289 ± 133 ng/ml) was significantly higher than that in those with a poor outcome (187 ± 75 ng/ml). During the clinical course of DIC, plasma TF antigen was increased first, and an increase of the plasma TFPI level followed the increase in plasma TF level. These findings suggest that plasma TFPI is released from vascular endothelial cells and it may reflect vascular endothelial cell injury. It is conceivable that TF and TFPI may play an important role in the onset of DIC. © 1996 Wiley-Liss, Inc.     

Plasma tissue factor and tissue factor pathway inhibitor levels in patients with disseminated intravascular coagulation

We measured the plasma levels of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with disseminated intravascular coagulation (DIC) to examine the relationship between TFPI and vascular endothelial cell injury. Plasma TF (273 ± 90 pg/ml) and TFPI (252 ± 125 ng/ml) levels were significantly increased in patients with DIC compared with non-DIC patients. Plasma TF antigen level was significantly increased in pre-DIC patients (285 ± 85 pg/ml), while the plasma TFPI level (152 ± 54 ng/ml) was not markedly increased in such a state. The plasma TF/TFPI ratio was high in the pre-DIC patients (2.10 ± 0.90), and low in the DIC patients (1.40 ± 0.87) and healthy volunteers (0.84 ± 0.26). There was no significant difference between the DIC patients with a good outcome and those with a poor outcome in terms of plasma TF levels, although the plasma TFPI level in the DIC patients with a good outcome (289 ± 133 ng/ml) was significantly higher than those with a poor outcome (187 ± 75 ng/ml). During the clinical course of DIC, plasma TF antigen was increased first, and an increase of the plasma TFPI level followed the increase in plasma TF level. These findings suggest that plasma TFPI is released from vascular endothelial cells and it may reflect vascular endothelial cell injury. It is conceivable that TF and TFPI may play an important role in the onset of DIC. Am. J. Hematol. 55:169–174, 1997. © 1997 Wiley-Liss, Inc.     

Fibrinolytic and plasmin inhibitor activities in patients with acute myocardial infarction

Fibrinolytic activity and plasmin inhibitor activity were determined by Blue Dextran-fibrin method in patients with acute myocardial infarction. The normal values of fibrinolytic activity and plasmin inhibitor activity were 3.34 +/- 0.74 units and 10.10 +/- 2.39 units (mean +/- SD), respectively. The fibrinolytic activity in normal women (3.63 +/- 0.99 units) was slightly higher than that in normal men (3.17 +/- 0.79 units), but the plasmin inhibitor was not significantly different in the two sexes statistically. Neither activity varied significantly with age. The blood fibrinolytic activity was depressed in the first week after acute myocardial infarction, the decrease being maximal 3 to 4 days after the event (1.73 +/- 0.31 units). The mean plasmin inhibitor activity remained normal after acute myocardial infarction, but it was increased in 3, and decreased in 4 of 7 patients in whom it was measured 3 to 4 days after the event.     

冠心病患者血浆组织因子和组织因子途径抑制物的变化

目的 :通过检测不同类型冠心病 (CHD)患者血浆组织因子 (TF)和组织因子途径抑制物 (TFPI)水平变化 ,探讨其在CHD发病过程中的作用。方法 :以酶联免疫吸附测定法测定CHD患者血浆中TF和TFPI抗原水平。结果 :不稳定型心绞痛 (UAP)和急性心肌梗死 (AMI)患者的血浆TF和TFPI水平与正常对照者和稳定型心绞痛 (SAP)患者相比均有显著性增高 (P <0 .0 5 ) ,以AMI患者尤为明显 (P <0 .0 1) ;UAP和AMI患者的TF PI/TF比值显著降低 (P <0 .0 5 ) ,而SAP患者的上述指标与正常对照者相比 ,其差异均无显著性意义 (P >0 .0 5 )。结论 :UAP和AMI患者TFPI/TF系统失衡 ,标志高凝状态的存在 ;TF和TFPI在这两种类型CHD的发病机制中可能起着重要的作用     

Effect of erythropoietin on tissue factor and tissue factor pathway inhibitor in uremic hemodialysis patients

Some parameters of extrinsic coagulation pathway, including concentration and activity of tissue factor and concentration of tissue factor pathway inhibitor, have been estimated in uremic hemodialysis patients. The impact of erythropoietin treatment on the extrinsic coagulation pathway has also been the aim of the study. Increased concentration of tissue factor pathway inhibitor--TFPI has been found both in dialysed and non-dialysed uremic patients. This finding may be the evidence of endothelial damage as well as the protective factor against thrombotic complications. Erythropoietin treatment seemed not to induce statistically significant changes in extrinsic coagulation pathway. Some results indicate that estimation of "truncated' and "full length" forms of TFPI may be more useful comparing to complete TFPI concentration.     

直接冠状动脉内支架置入术对急性心肌梗死无复流的影响

目的评价直接冠状动脉(冠脉)内支架置入术对ST段抬高型急性心肌梗死无复流的影响。方法对157例ST段抬高型急性心肌梗死患者分别行直接冠脉内支架置入(直接支架组,85例)和球囊预扩张后支架置入(常规支架组,72例)。比较两组介入治疗时平均X线曝光时间、造影剂用量、术后TIMI血流分级和心电图ST段变化。结果直接支架组和常规支架组比较,前者节省球囊,平均X线曝光时间和造影剂用量均显著降低[(24.6±16.9)minvs(34.4±17.5)min,(115±37)mLvs(166±61)mL;P均<0.05];二者术后TIMI3级差异无统计学意义(91.8%vs83.3%,P=0.107);前者TIMI0~1级未见显著降低,但有明显的下降趋势(3.5%vs11.1%,P=0.064);前者心电图ST段无回落发生率显著降低(22.4%vs41.7%,P=0.009)。结论对于ST段抬高型急性心肌梗死中适当的冠脉病变,直接冠脉内支架置入术不仅可以节省球囊,减少X线曝光时间和造影剂用量,而且可能减少无复流发生。