Exome Sequencing and Clot Lysis Experiments Demonstrate the R458C Mutation of the Alpha Chain of Fibrinogen to be Associated with Impaired Fibrinolysis in a Family with Thrombophilia.

AIM: We report the study of a familial rare disease with recurrent venous thromboembolic events that remained undiagnosed for many years using standard coagulation and hemostasis techniques. METHODS: Exome sequencing was performed in three familial cases with venous thromboembolic disease and one familial control using NimbleGen exome array. Clot lysis experiments were performed to analyze the reasons of the altered fibrinolytic activity caused by the mutation found. RESULTS: We found a mutation that consists of a R458C substitution on the fibrinogen alpha chain (FGA) gene confirmed in 13 new familial subjects that causes a rare subtype of dysfibrinogenemia characterized by venous thromboembolic events. The mutation was already reported to be associated with a fibrinogen variant called fibrinogen Bordeaux. Clot-lysis experiments showed a decreased and slower fibrinolytic activity in carriers of this mutation as compared to normal subjects, thus demonstrating an impaired fibrinolysis of fibrinogen Bordeaux. CONCLUSIONS: The exome sequencing and clot-lysis experiments might be powerful tools to diagnose idiopathic thrombophilias after an unsuccessful set of biochemical laboratory tests. Fibrinogen Bordeaux is associated with impaired fibrinolysis in this family with idiopathic thrombophilia.

Lower tissue factor inhibition in patients with ST segment elevation than in patients with non ST elevation acute myocardial infarction.

INTRODUCTION: Mechanisms to explain the different course of coronary thrombosis between ST elevation myocardial infarction (STEMI) and non-STEMI patients remain poorly defined. We hypothesize, however, that STEMI patients may present lower tissue factor plasma inhibition to partly account for their more persistent coronary thrombotic occlusion. MATERIALS AND METHODS: Total (t-TFPI ) and free tissue factor plasma inhibitor (f-TFPI), thrombin-antithrombin complex (TAT), plasminogen activator inhibitor 1 (PAI-1), von Willebrand factor (vWF), and fibrinogen were measured on admission and at 3 and 6 months in patients with a first STEMI (n:69) or non-STEMI (n:60). C reactive protein (CRP) was also measured on admission and at 3 months. RESULTS: STEMI patients showed lower admission levels of t-TFPI (p=0.001), f-TFPI (p=0.030) and fibrinogen (p=0.022), and higher vWF levels (p=0.005) than non-STEMI whereas TAT, PAI and CRP levels were comparable. At 3 and 6 months VWF, t-TFPI, f-TFPI, and TAT levels declined significantly in the 2 groups (p=0.002) reaching similar values. CRP levels also declined at 3 months (p=0.002). Moreover, the rate of cardiac mortality, non fatal MI or stroke during a 6 year follow-up were unrelated to admission coagulation parameters. CONCLUSIONS: The lower inhibition of tissue factor and greater endothelial dysfunction in STEMI than in non-STEMI patients may enhance thrombosis at the culprit lesion and adjacent coronary plaques, and hence, account at least in part for their different pathophysiology. This condition, however, is limited to the acute phase.

Prothrombotic profile in patients with vasospastic or non vasospastic angina and non significant coronary stenosis.

BACKGROUND: Patients with vasospastic (VA) or non vasospastic angina (NVA) without significant coronary stenosis have a reduced risk of infarction but is unclear whether or not this may be attributable to a lack of prothrombotic profile - similar to that present in patients with stable coronary artery disease (CAD). METHODS: Plasma levels of von Willebrand factor, total and free tissue factor pathway inhibitor, plasminogen activator inhibitor-1, and fibrinogen were analyzed in 15 patients with stable VA and 23 with NVA, all with vasoconstrictive response to acetylcholine although with different severity. Results were compared with those of 20 age-matched controls and 10 patients with CAD. RESULTS: Plasma levels of von Willebrand factor in patients with VA or NVA were higher than in controls (207 ± 62 and 203 ± 69% vs 121 ± 38%, p < 0.001) and tended to be lower than in CAD patients (264 ± 65, p = 0.145). They also presented higher total tissue factor pathway inhibitor (123 ± 18 and 111 ± 25 vs 88 ± 14, ng/ml p < 0.001) and plasminogen activator inhibitor-1 levels than controls (51 ± 30 and 52 ± 31% vs 19 ± 9 ng/ml, p < 0.001) and similar to CAD patients (134 ± 23 and 62 ± 31, respectively, ns). Moreover, free tissue factor pathway inhibitor plasma levels were lower than controls (18 ± 5 and 17 ± 5 vs 23 ± 8 ng/ml, p = 0.002) and similar to CAD patients (14 ± 5, ns). Despite this prothrombotic condition none of VA or NVA patients presented a myocardial infarction during a 9 year follow-up, an observation also reported in larger series. CONCLUSIONS: During a stable phase of their disease, patients with VA or NVA present a prothrombotic profile that might eventually contribute to occurrence of myocardial infarction. The rarity of these events, however, may suggests that ill defined factors would protect these patients from coronary plaque rupture/fissure.

Disfunción endotelial y desequilibrio hemostásico en el síndrome X cardiológico / Endothelial dysfunction and hemostatic imbalance in cardiological syndrome X

Introducción: La posible existencia de disfunción endotelial y desequilibrio hemostásico en síndrome X cardiológico, frecuente en la posmenopausia, es un tema controvertido. Objetivo: Comparar los biomarcadores: factor de Von Willebrand (FvW), fibrinógeno (Fb), inhibidor del factor tisular total (TFPI-t) y del activador del plasminógeno (PAI-1) en pacientes sin enfermedad arterial coronaria (síndrome X cardiológico, angina mixta y angina vasoespástica) y pacientes con enfermedad arterial coronaria. Material y métodos: Se determinaron estos biomarcadores en 10 pacientes con síndrome X cardiológico, en 13 con angina mixta, en 15 con angina vasoespástica, en 10 con enfermedad arterial coronaria y en 20 controles sanos. Resultados: Respecto del control sano, todas las pacientes presentaron valores elevados de Fb (3,1 g/l [2,7-3,6] frente a 2,8 g/l [2,2-3,2]; p - 0,03), FvW (211,9% [165-266] frente a 116,5% [91-155]; p < 0,001), TFPI-t (122,3 ng/ml [101-136] frente a 86 ng/ml [72-100]; p < 0,001) y PAI-1 (45,9 ng/ml [32-61] frente a 21 [11-26] ng/ml; p < 0,001). Sin embargo, los pacientes sin enfermedad arterial coronaria respecto de los pacientes con enfermedad arterial coronaria presentaron niveles menores de FvW (200,5% [151-249] frente a 255,2% [221-277]; p - 0,01) y TFPI-t (110,5 ng/ml [100-127] frente a 136,7 [121-148] ng/ml; p - 0,02]. Conclusión: Los pacientes con síndrome X cardiológico presentan una situación de disfunción endotelial y de desequilibrio hemostásico similar a aquellos con angina mixta o angina vasoespástica, aunque menos severo que en pacientes con enfermedad arterial coronaria

Introduction: The possible presence of endothelial dysfunction and hemostatic imbalance in cardiological syndrome X, frequent in the postmenopause, remains controversial. Objective: To compare the biomarkers von Willebrand factor (vWF), fibrinogen (Fb), total tissue factor pathway inhibitor (TFPI-t) and plasminogen activator inhibitor (PAI-1) between patients without coronary artery disease (cardiological syndrome X, mixed angina and vasospastic angina) and patients with coronary artery disease. Material and methods: These biomarkers were determined in 10 patients with cardiological syndrome X, 13 patients with mixed angina, 15 patients with vasospastic angina, 10 patients with coronary arterial disease and 20 healthy controls. Results: Compared with healthy controls, all patients had elevated levels of Fb [3.1 (2.7-3.6) vs 2.8 (2.2-3.2) g/l; P -.003], vWF [211.9 (165-266) vs 116.5 (91-155)%, TFPI-t [122.3 (101-136) vs 86 (72-100) ng/ml; P<.001] and PAI-1 [45.9 (32-61) vs 21 (11-26) ng/ml; P<.001]. However, patients without coronary artery disease had lower levels of vWF [200.5 (151-249) vs 255.2 (221-277) %; P -.01)] and TFPI-t [110.5 (100-127) vs 136.7 (121-148) ng/ml; P -.02)] than those with coronary artery disease. Conclusion: The presence of endothelial dysfunction and hemostatic imbalance is similar in patients with cardiological syndrome X and those with mixed or vasospastic angina, although these disorders are less severe than in patients with coronary artery disease

Angiogenic factors and angiogenesis inhibitors in exudative pleural effusions.

The angiogenesis system has been implicated in inflammatory and neoplastic processes; nevertheless, it has been little studied in relation to the pleural space. Our aim is to analyze pleural and plasma levels of the activators--vascular endothelial growth factor, basic fibroblastic growth factor, and inhibitors--endostatin and thrombospondin-1 and to estimate the association between these factors and related biochemical markers. We analyzed pleural fluid from 105 patients with one of the following types of pleural effusion: empyema or complicated parapneumonic, non-complicated parapneumonic, tuberculous, neoplastic and transudative. Angiogenesis activators were higher in exudates than in transudates (p < 0.001) and in empyema than in non-complicated parapneumonic patients (p < 0.001). Endostatin showed no significant differences. Trombospondin-1 showed higher levels in exudates than in transudates and in empyema than in non-complicated parapneumonic effusions (p < 0.001). In pleural exudates there was a positive correlation of angiogenesis activators and trombospondin-1 with low glucose and pH and high LDH. There was no correlation between pleural and plasma levels of the angiogenesis factors. We conclude that exudative pleural effusions showed higher vascular endothelial growth factor, basic-fibroblastic growth factor and trombospondin-1 values than transudative effusions that associated to low glucose and pH, and high LDH. There was no correlation between pleural and plasma concentrations, suggesting a compartmentalized response.

Increased plasma fibrinolytic activity in bleeding gastrointestinal angiodysplasia.

OBJECTIVE: Gastrointestinal angiodysplasia is a major cause of recurrent bleeding. Haemostatic abnormalities have been implicated in the haemorrhage from these common vascular lesions but their precise contribution remains to be established. Our aim was to investigate whether bleeding angiodysplasia is associated with any specific coagulation disorder. METHODS: Clinical features and blood samples were prospectively obtained from 21 patients with bleeding gastrointestinal angiodysplasia 3 months after the last episode of haemorrhage. Plasma levels of von Willebrand factor, D-dimer, plasminogen activator inhibitor type 1 (PAI-1), tissue-plasminogen activator activity, tissue factor pathway inhibitor and activated factor VII (FVIIa-rTF) were measured. A group of 14 patients with bleeding duodenal ulcer were similarly studied as controls. RESULTS: Mean plasma von Willebrand factor levels were higher in angiodysplasia patients (208+/-12%) than in controls (143+/-11%) (P<0.05). D-dimer levels (661+/-80 ng/ml) and tissue-plasminogen activator activity levels (2.04+/-0.14 IU/ml) were also higher than in controls: 395+/-99 ng/ml and 1.6+/-0.1 IU/ml, respectively (P<0.05), whereas levels of PAI-1, FVIIa-rTF and tissue factor pathway inhibitor were similar in both groups. However, PAI-1 levels (31.5+/-11 ng/ml) were lower in high-bleeding-rate angiodysplasia (more than two bleeding episodes/year) than in low-bleeding-rate angiodysplasia (< or = 2 bleeding episodes/year) (PAI-1 47+/-14 ng/ml) (P<0.05). In a multivariate regression analysis, the plasma level of PAI-1 was a predictor of haemorrhage from angiodysplasia (P<0.05). CONCLUSIONS: Increased plasma fibrinolytic activity may contribute to bleeding from angiodysplasia. Low plasma PAI-1 levels constitute a risk factor for bleeding tendency in patients with angiodysplasia.

Temporal profile of matrix metalloproteinases and their inhibitors after spontaneous intracerebral hemorrhage: relationship to clinical and radiological outcome.

BACKGROUND AND PURPOSE: Matrix metalloproteinases (MMPs) are related to blood-brain barrier disruption, and some members of this family have been recently involved in brain bleedings. We aimed to investigate the temporal profile of MMPs and their natural inhibitors (TIMPs) after acute intracerebral hemorrhage (ICH) and to study its influence on neuroimaging and clinical outcome. METHODS: MMP-2, MMP-9, and MMP-3, as well as TIMP-1 and TIMP-2, were serially determined by enzyme-linked immunosorbent assay on admission (<12 hours), and at 24 hours, 48 hours, 7 days, and 3 months in 21 ICH patients. ICH and perihematomal edema (PE) volumes were serially measured on baseline and follow-up computed tomography (48 hours, 7 days, and 3 months), just at the time of neurological assessment. RESULTS: Deep ICH was found in 62% patients. Baseline ICH volume did not influence MMP-TIMP level. Highest levels of MMP-2 and TIMP-2 were found at baseline, for MMP-9 and TIMP-1 at 24 hours, and for MMP-3 at 24 to 48 hours. Baseline MMP-9 was positively correlated to PE volume (r=0.67, P=0.004) and, conversely, its inhibitor TIMP-1 was negatively correlated to PE (r=-0.51, P=0.04). Mortality reached 35% and MMP-3 was the only MMP/TIMP related to mortality (7.5 versus 2.4 ng/mL; P=0.035) and its most powerful baseline predictor (odds ratio = 22, confidence interval: 1.5 to 314.2). Both MMP-9 and MMP-3 correlated to the residual scar volume at 3 months (r=0.68, P=0.01 for baseline MMP-9, and r=0.86, P<0.001 for 24-hour MMP-3). CONCLUSIONS: A characteristic temporal profile of MMP/TIMP release exists in ICH. Increased MMP-9 is associated with PE, and increased MMP-3 is associated with mortality. Both molecules are related to residual cavity volume.

Plasmatic level of neuroinflammatory markers predict the extent of diffusion-weighted image lesions in hyperacute stroke.

Sixteen patients with acute middle cerebral artery stroke were studied to correlate neuroinflammatory markers with perfusion- and diffusion-weighted magnetic resonance imaging (MRI) lesion volumes (PWI and DWI). At arrival (less than 6 hours), plasmatic matrix metalloproteinase (MMP)-9, MMP-2, interleukin (IL)-6, IL-8, intercellular adhesion molecule (ICAM)-1, and tumor necrosis factor (TNF)-alpha were serially measured (by ELISA), and MRI was performed. In cerebral ischemia, tissue destruction seems related to matrix metalloproteinases expression because baseline MMP-9 was the only predictor of the infarct volume measured as a DWI lesion (lineal regression: b = 0.50, 0.25-0.74; P < 0.001). Moreover, the extent of hypoperfused brain area (PWI) was associated with a proinflammatory cytokine release in the next hours (TNF-alpha and IL-6).

Safety profile of tissue plasminogen activator treatment among stroke patients carrying a common polymorphism (C-1562T) in the promoter region of the matrix metalloproteinase-9 gene.

BACKGROUND AND PURPOSE: Matrix metalloproteinase-9 (MMP-9) expression, related to blood-brain barrier disruption, has been implicated in the appearance of hemorrhagic transformation (HT) after tissue plasminogen activator (tPA) treatment in stroke patients. Because an in vitro functional polymorphism of the promoter region of MMP-9 gene (C-1562T) has been described, we hypothesize that patients carrying this mutation might have higher MMP-9 levels and greater susceptibility to developing HT when receiving tPA. METHODS: We studied strokes involving the middle cerebral artery territory of 61 patients who received tPA <3 hours after stroke onset. Blood samples were obtained before tPA administration. Plasmatic MMP-9 determinations were performed (enzyme-linked immunosorbent assay, ng/mL), and C-1562T genotype was determined by polymerase chain reaction. Healthy age-matched control subjects were used to study allele distribution (n=59). Hemorrhagic events were classified according to CT criteria (petechial hemorrhagic infarctions [HI,1 to 2] and large parenchymal hemorrhages [PH,1 to 2]). RESULTS: Allele distribution was similar in patients and control subjects (CC/CT/TT: 72.3/27.7/0% versus 79.7/20.3/0%, respectively; P=0.37). Among patients, mutation carriers (CT/TT alleles) had similar rates of HT and PH than noncarriers (HT: 23.1% versus 38.2%, P=0.49; PH: 15.4% versus 17.6%, P=1.0). Although the highest MMP-9 level corresponded to patients who later developed a PH (PH, 191.4 ng/mL; non-PH, 68.05 ng/mL; P=0.022), no relation between MMP-9 mutation presence and plasmatic levels was found (CC, 127.12 ng/mL; CT/TT, 46.31 ng/mL; P=0.11). CONCLUSIONS: Although MMP-9 level predicts PH appearance after tPA treatment, no relationship exists with the C-1562T polymorphism, probably because this mutation is not functional in response to cerebral ischemia in vivo.

Matrix metalloproteinase-9 concentration after spontaneous intracerebral hemorrhage.

OBJECT: Matrix metalloproteinases (MMPs) are overexpressed in the presence of some neurological diseases in which blood-brain barrier disruption exists. The authors investigated the MMP-9 concentration in patients after acute intracerebral hemorrhage (ICH) and its relation to perihematomal edema (PHE). METHODS: Concentrations of MMP-9 and related proteins were determined in plasma by performing an enzyme-linked immunosorbent assay of samples drawn after hospital admission (< 24 hours after stroke) from 57 patients with ICH. The diagnosis of ICH was made on the basis of findings on computerized tomography (CT) scans. The volumes of ICH and PHE were measured on baseline and follow-up CT scans at the same time that the patient's neurological status was assessed using the Canadian Stroke Scale and the Glasgow Coma Scale. Increased expression of MMP-9 was found among patients with ICH. In cases of deep ICH, MMP-9 was significantly associated with PHE volume (r = 0.53; p = 0.01) and neurological worsening (237.4 compared with 111.3 ng/ml MMP-9; p = 0.04). A logistic regression model focusing on the study of absolute PHE volume showed ICH volume as an independent predictor (odds ratio [OR] 3.37; 95% confidence interval [CI] 1.1-10.3; p = 0.03). A second analysis of relative PHE volume (absolute PHE volume/ICH volume) in patients with deep ICH demonstrated that the only factor related to it was MMP-9 concentration (OR 11.6; 95% CI 1.5-89.1; p = 0.018). CONCLUSIONS: Expression of MMP-9 is raised after acute spontaneous ICH. Among patients with deep ICH this increase is associated with PHE and the development of neurological worsening within the acute stage.

Association between inflammatory mediators and the fibrinolysis system in infectious pleural effusions.

The response of the fibrinolytic system to inflammatory mediators in empyema and complicated parapneumonic pleural effusions is still uncertain. We prospectively analysed 100 patients with pleural effusion: 25 with empyema or complicated parapneumonic effusion, 22 with tuberculous effusion, 28 with malignant effusion and 25 with transudate effusion. Inflammatory mediators, tumour necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8) and polymorphonuclear elastase, were measured in serum and pleural fluid. Fibrinolytic system parameters, plasminogen, tissue-type plasminogen activator (t-PA) and urokinase PA, PA inhibitor type 1 (PAI 1) and PAI type 2 concentrations and PAI 1 activity, were quantified in plasma and pleural fluid. The Wilcoxon signed-rank test was used to compare plasma and pleural values and to compare pleural values according to the aetiology of the effusion. The Pearson correlation coefficient was used to assess the relationship between fibrinolytic and inflammatory markers in pleural fluid. Significant differences were found between pleural and plasma fibrinolytic system levels. Pleural fluid exudates had higher fibrinolytic levels than transudates. Among exudates, tuberculous, empyema and complicated parapneumonic effusions demonstrated higher pleural PAI levels than malignant effusions, whereas t-PA was lowest in empyema and complicated parapneumonic pleural effusions. PAI concentrations correlated with TNF-alpha, IL-8 and polymorphonuclear elastase when all exudative effusions were analysed, but the association was not maintained in empyema and complicated parapneumonic effusions. A negative association found between t-PA and both IL-8 and polymorphonuclear elastase in exudative effusions was strongest in empyema and complicated parapneumonic effusions. Blockage of fibrin clearance in empyema and complicated parapneumonic effusions was associated with both enhanced levels of PAIs and decreased levels of t-PA.

Thrombin-activable fibrinolysis inhibitor levels in the acute phase of ischemic stroke.

BACKGROUND AND PURPOSE: Thrombin-activable fibrinolysis inhibitor (TAFI) is a recently identified fibrinolysis inhibitor in plasma. The purpose of this work was to study TAFI levels in the acute phase of ischemic stroke and their relationship with stroke evolution. METHODS: In 30 consecutive ischemic stroke patients, TAFI plasma levels were measured by means of enzyme-linked immunosorbent assay (percentage of the pooled reference kit expressed as mean+/-SD) and compared with the values obtained in 30 healthy control subjects. All samples were drawn within the first 24 hours after symptom onset (mean, 4.6 hours) and before any treatment was started. RESULTS: TAFI plasma concentration was significantly higher (P<0.001) in stroke patients (158.4+/-53.2%) than in healthy control subjects (105.6+/-30.2%). The highest TAFI levels were found in cases of neurological deterioration (worsening, 198.1+/-63.0%; stability, 130.5+/-39.3%; improvement, 173.9+/-52.0%; P=0.057). CONCLUSIONS: High levels of TAFI are found in the acute phase of ischemic stroke.

Matrix metalloproteinase-9 pretreatment level predicts intracranial hemorrhagic complications after thrombolysis in human stroke.

BACKGROUND: Matrix metalloproteinase (MMP) expression is related to blood brain barrier disruption after cerebral ischemia. Moreover, MMP inhibitors reduce hemorrhagic transformation (HT) after embolic ischemia in tissue plasminogen activator (t-PA)-treated animals. We aimed to correlate plasmatic MMP levels with the appearance of intracranial bleeding complications in stroke patients treated with t-PA. METHODS AND RESULTS: Serial MMP-2 and MMP-9 determinations were performed (ELISA, ng/mL) in 41 strokes involving the middle cerebral artery territory in patients who received t-PA within 3 hours of stroke onset. Blood samples were obtained at baseline (pretreatment) and at 12 and 24 hours after symptom onset. Hemorrhagic events were classified according to CT criteria (petechial hemorrhagic infarctions [HI, 1 to 2] and large parenchymal hemorrhages [PH, 1 to 2]). Brain CT scan was obtained at 48 hours or when a neurological worsening occurred. HT was present in 36.5% of the patients (24.4% HI and 12.1% PH). MMP-2 values were unrelated to any subtype of HT. The highest baseline MMP-9 level (normal range <97 ng/mL) corresponded to patients who later developed a PH (PH: 270.2+/-87.8, non-HT: 126.3+/-127.5, HI: 94.6+/-88.7; P=0.047). A graded response was found between mean baseline MMP-9 levels and the degree of bleeding (HI-1=37.4; HI-2=111.0; PH-1=202.5; PH-2=337.8). Baseline MMP-9 was the most powerful predictor of PH appearance in the multiple logistic regression model (OR= 9.62; CI 1.31 to 70.26; P=0.025). CONCLUSIONS: Baseline MMP-9 level predicts PH appearance after t-PA treatment. Therefore, we suggest that MMP determination may increase the safety profile for thrombolysis and, in the future, anti-MMP drugs might be combined with t-PA to prevent hemorrhagic complications.