Calibrated automated thrombin generation and modified thromboelastometry in haemophilia A

Introduction

Global coagulation tests may have a better relation with phenotype in haemophilia than traditional coagulation tests. These include the Calibrated Automated Thrombin generation assay (CAT) and modified thromboelastometry using low tissue factor triggering. Both have shown marked variability in thrombin generation and clot formation profiles respectively despite similar FVIII:C levels and have been suggested as means to monitor treatment. Data with modified thromboelastometry are largely limited to severe and moderate haemophiliacs. CAT measurements in haemophilia are generally performed at low TF concentrations (1 pM) because of a higher sensitivity for the intrinsic pathway at this concentration but is also sensitive for FVIII at higher concentrations (5 pM) and this has the advantage that inhibition of contact factor activation can be avoided. No formal comparison of both TF concentrations has been reported and the data on modified thromboelastometry in mild haemophilia are limited.

Methods

In this study we compared thrombin generation at 1 and 5 pM in 57 haemophilia patients without exposure to treatment and 41 patients after treatment. We also assessed the sensitivity of thromboelastometry for haemophilia A in 29 patients.

Results and conclusion

We found that CAT discriminates well between normal individuals and haemophilia patients; also FVIII:C correlates well with the ETP/peak. We found no clear advantages of measurements at 1 compared to 5 pM but found increased variation over time at 1 pM. The sensitivity of modified thromboelastometry for haemophilia A was less than CAT with abnormal measurements largely limited to severe and moderate patients. Larger studies correlating both methods with clinical outcome are required.     

Chylothorax in children with congenital heart disease: Incidence of thrombosis

Postoperative chylothorax is a frequently encountered pathology occurring in up to 4% of patients undergoing surgery for repair of congenital heart disease. Symptomatic thrombosis is associated with chylothorax and may contribute to its severity and duration. Furthermore, vessel thrombosis resulting in persistent vessel occlusion may impede future treatments, diagnostic studies and cardio-surgical interventions. The objective of this study was to determine the incidence of upper system thrombosis in pediatric congenital heart patients with confirmed chylothorax with ultrasound screening of all patients diagnosed with chylothorax. All pediatric patients with confirmed with chylothorax underwent doppler ultrasound of the upper venous system as per hospital standard. This retrospective cohort study enrolled all children between February 1, 2010-August 2012, post cardiac surgery with confirmed chylothorax to determine the incidence of all thrombosis. There were 1396 children who underwent 1396 cardiac surgical procedures during the study time with 760 undergoing cardiopulmonary bypass. Development of chylothorax occurred in 54 of 1396, 3.9% (95%CI 3.0;5.0) procedures in all children. In those children with chylothorax, 28 of 54 episodes, 51.8% (95%CI 38.9;64.6) had confirmed VTE. The 51.8% incidence in this study demonstrates a 2.6 fold increase in risk of thrombosis compared to 20% in children with heart disease and central venous lines and may result in serious clinical consequences. The contribution of upper venous system thrombosis to chylothorax is unknown. Often, clinical suspicion of chylothorax exists, however the lack of a standardized approach to objective diagnosis results in delayed confirmation. Approaches to therapy either treatment of confirmed thrombosis or prevention of thrombosis in patients with chylothorax require formal evaluation. Future studies are urgently needed.     

Calibrated automated thrombography demonstrates hypercoagulability in patients with idiopathic pulmonary arterial hypertension

Introduction

Pathogenesis of idiopathic pulmonary arterial hypertension (iPAH) includes endothelial dysfunction and in situ thrombosis. A hypercoagulable state has also been postulated but never demonstrated. Our objective was to determine whether patients with iPAH had a hypercoagulable state using calibrated automated thrombography (CAT), a new tool to phenotype coagulation in vitro.

Patients and methods

16 patients with iPAH and 29 controls were studied. In vitro platelet dependent coagulation phenotyping by CAT monitored the activity of thrombin generation over time. Plasma levels of soluble thrombomodulin, tissue factor pathway inhibitor (TFPI) and von Willebrand factor (VWF) were measured as endothelial biomarkers.

Results

Endogenous thrombin potential (ETP) in the absence of activated protein C (APC) tended to be increased in patients compared to controls (1769 versus 1656 nM.min; p = 0.053). ETP was higher in the presence of APC 25 nM (ETP-APC) in patients (781 versus 494 nM.min; p = 0.005). Five patients had ETP-APC higher than the 95th centile of controls. Other CAT parameters (lag time, peak thrombin and time to peak) were all consistent with some degree of hypercoagulability in patients. Regarding endothelial plasma biomarkers sTM was lower (28.4 versus 40.6 μg/l, p = 0.0108) in patients; TFPI antigen and activity (respectively: 14.3 versus 10.5 μg/l, p = 0.0167; 1.155 versus 1.070, p = 0.0021) and VWF (1300 versus 976%, p = 0.0108) were higher in patients.

Conclusion

We have demonstrated that at least some patients with iPAH have a hypercoagulable phenotype.     

Factors associated with adverse neurodevelopmental outcomes in infants with congenital heart disease

OBJECTIVE: To review reported neurodevelopmental outcome data for patients with congenital heart disease, identify risk factors for adverse neurodevelopmental sequelae and summarize potential neuromonitoring strategies that have been described. METHODS: A Medline search was performed utilizing combinations of the keywords congenital heart, cardiac, neurologic, neurodevelopment, neuromonitoring, quality of life, and outcome. All prospective and longitudinal follow-up studies of patients with congenital heart disease were included. Additionally, studies that examined neuroimaging, neuromonitoring, and clinical factors in relation to outcome were examined. Case reports and editorials were excluded. Additional references were retrieved from selected articles if the abstract described an evaluation of neurodevelopmental outcomes and/or predictors of outcome in patients with congenital heart disease. RESULTS: Overall, patients with CHD have increased rates of neurodevelopmental impairments, although intelligence appears to be in the normal range. Preoperative risk stratification, intraoperative techniques, postoperative care, and neuromonitoring strategies may all contribute to ultimate long-term neurodevelopmental outcomes in patients with CHD postsurgical repair. CONCLUSIONS: As advances in the medical and surgical management improves survival in patients with CHD, increasing knowledge about neurodevelopmental outcomes and the factors that affect them will provide for strategies to optimize long-term outcome in this high-risk population.     

Women with unexplained recurrent pregnancy loss do not have evidence of an underlying prothrombotic state: Experience with calibrated automated thrombography and rotational thromboelastometry

Introduction

Where unexplained recurrent pregnancy loss (RPL) is attributed to an underlying maternal prothrombotic state, empirical prophylactic anticoagulation may be recommended.

Materials and Methods

In the present study we used calibrated automated thrombography and rotational thromboelastometry to determine the procoagulant potential of these women as a rationale for anticoagulation. Fifty women with ≥ three consecutive unexplained losses prior to 14 weeks’ gestation or one loss after this time were compared with forty-one parous women with no miscarriages. Exclusion criteria included antiphospholipid syndrome, inherited thrombophilia and prior venous thromboembolism. Thrombin generation in platelet poor plasma and whole blood thromboelastometry was performed outside pregnancy to determine the presence or not of an underlying prothrombotic state.

Results

Peak thrombin and endogenous thrombin potential were not significantly increased in subjects relative to controls. The use of low tissue factor (1 pM) to better reflect physiological conditions and assay modification to better assess the protein C pathway (5 pM in the presence of thrombomodulin) provided no additional discrimination. Consistent results were shown with thromboelastometry; mean parameters were equivalent between subjects and controls.

Conclusions

These data demonstrate that global coagulation assays provide no evidence of an underlying hypercoagulable state in women with unexplained RPL; this is in keeping with the results of recent randomised controlled trials and strengthens the evidence base against use of anticoagulants in this setting.     

Brain changes in newborns,infants and children with congenital heart disease in association with cardiac surgery. Additional observations

Summary The histopathologic pattern in the Central Nervous System in 12 out of 21 new-borns and young infants, below 2 months of age, operated for various congenital heart defects, is that of recent necroses in the deep and subcortical white matter of the pallium, seen from a few hours to 8 days following completion of surgery. Type and location of these lesions of ischemic coagulative necrosis, resembling findings in the perinatal respiratory distress syndrome, seem to depend on shock-like states, the low output syndrome of the left heart with hypovolemia and hypotension. The cause of death in all these infants was cardio-respiratory failure. The question to what extent glial scars replacing necroses within the mostly nonmyelinated fiber systems of the pallium will lead to defective maturation of the brain in later infancy and childhood remains a challenge for neurologic and psychological investigation, even if the heart defect has been successfully repaired by the surgeon.Post-mortem data of the CNS in 24 older infants and children below 9 years of age in association with cardia surgery include thrombembolic infarctions, also, after catheterization alone, diffuse or segmental cortical necroses, and cortical scars, especially in children older than 1 year, confirming data recently reported from this laboratory.Read in part before the Meeting of the American Association of Pathologists and Bacteriologists, in San Francisco, March 12th, 1974. Abstracted in Amer. J. Path., Vol. 74, Scientific Proceedings, 91a (1974).     

A cross-sectional study of the prevalence of psychopathology in adults with congenital heart disease

OBJECTIVE: Several studies have suggested high levels of psychopathology in children and adolescents with congenital heart disease (CHD). However, little information is published relating to psychopathology in adults with CHD. We wanted to estimate the prevalence of psychopathology in adults with CHD. DESIGN: A cross-sectional study of attenders at an adult CHD clinic compared with orthopaedic outpatients of the same hospital. SETTING: A tertiary CHD clinic in South Wales, the comparison group being recruited from the orthopaedic outpatient clinic in the same teaching hospital. PARTICIPANTS: One hundred and one individuals attending the CHD clinic were identified, 87 successfully completed questionnaires. Forty-five from 80 randomly selected orthopaedic outpatients completed questionnaires. MAIN OUTCOME MEASURES: The General Health Questionnaire 30 (GHQ30) and the Hospital Anxiety and Depression Scale (HADS). RESULTS: We found a statistically significant difference in the mean GHQ 30 score between the CHD and comparison groups, the CHD group having lower scores. The difference remained after adjustment for age and sex. The mean HADS scores differed in the same direction, and were of borderline statistical significance. CONCLUSIONS: In this study, adult subjects with CHD had a lower prevalence of psychopathology. Possible explanations for this finding are discussed.     

Comparison of markers of coagulation activation and thrombin generation test in uncomplicated pregnancies

Introduction

Pregnancy is a well-established risk factor for venous thromboembolism, and is associated with a state of hypercoagulability or parameters of thrombin generation. Currently, there is a lack of consensual data on thrombin generation during pregnancy. This study aimed to find a sensitive and specific biological marker of coagulation activation and to identify parameters of thrombin generation.

Patients and methods

The population included 101 women with uncomplicated pregnancies. The objective of this study was to correlate thrombin generation test (measured at 5pM tissue factor, 4 μM lipids and without thrombomodulin), with fibrinogen and markers of blood coagulation activation: D-dimer, prothrombin fragments 1+2 (F1+2), thrombin-antithrombin complexes (TAT) and fibrin monomer complexes (FMC) in these women. Internal quality control was performed in each set of experiments.

Results

Fibrinogen, D-dimer, F1+2, and TAT concentrations increased significantly throughout pregnancy, and were correlated with term of pregnancy. In our study, thrombin generation seemed to increase early on, and then remained stable throughout normal pregnancy, in contrast with other markers of blood coagulation activation, excepting FMC. The latter are subject to large inter-individual variations, especially during second trimester. No correlation was demonstrated between thrombin generation parameters and other activation markers.

Conclusion

While markers of coagulation activation significantly increased during pregnancy, thrombin generation increased only early on and remains stable during pregnancy. Finding a sensitive and specific biological marker for vascular pregnancy complications, such as FMC and thrombin generation levels, requires further investigation.     

Plasma haemostatic potential of haemodialysis patients assessed by thrombin generation assay: Hypercoagulability in patients with vascular access thrombosis

Introduction

Patients with end-stage renal disease (ESRD) on maintenance haemodialysis are predisposed to bleeding and thrombotic events. Recently thrombin generation assay (TGA) has been introduced as a laboratory assessment of global haemostatic potential. We investigated the global haemostatic potential assessed by TGA in ESRD patients on haemodialysis and patients who developed vascular access thrombosis.

Materials and Methods

A total of 69 ESRD patients who underwent haemodialysis (58 stable patients and 11 vascular access thrombosis patients) were included and 33 healthy controls were included. TGA was performed on the calibrated automated thrombogram using tissue factor with/without addition of thrombomodulin or activated protein C, producing three parameters including lag time, endogenous thrombin potential (ETP) and peak thrombin.

Results

Haemodialysis patients showed low ETP values measured by thrombin generation assay compared with the healthy controls. Interestingly, patients with vascular access thrombosis exhibited short PT and aPTT and increased resistance of coagulation inhibition to APC anticoagulant protein, reflecting hyper-coagulability. Haemodialysis patients who are taking anti-platelet agents showed decreased thrombin inhibition rate, representing antithrombotic effect of anti-platelet agents.

Conclusion

Whereas the haemodialysis patients showed hypo-coagulability, the patients with vascular access thrombosis exhibited hyper-coagulability. Further study is required to investigate how this haemostatic potential may be utilized to guide the physician to more effective management of haemostatic complication.     

High haematocrit in cyanotic congenital heart disease affects how fibrinogen activity is determined by rotational thromboelastometry

Introduction

Viscoelastometry enables rapid evaluation of coagulopathy in settings such as cardiac surgery but may be influenced by red cell concentration.

Methods

In order to study the effects of supra-physiological red cell concentrations on viscoelastometry, we compared ROTEM® viscoelastometry and plasma coagulation assay results in high haematocrit (HCT; 0.55-0.76 L/L) blood from patients with cyanotic congenital heart disease (CCHD), and in model high HCT blood (HCT 0.45-0.70 L/L).

Results

High HCT blood from CCHD patients (median HCT 0.66 L/L) displayed prolonged clot initiation in the EXTEM® test compared to controls and reduced maximum clot firmness (MCF) in the EXTEM (median 51 mm vs 64 mm in controls) and FIBTEM® (7 mm vs 14 mm) tests. The plasma fibrinogen (Clauss; CF) was similar in CCHD blood to controls (median 2.94 g/L vs 2.49) but the whole blood fibrinogen concentration (WBFC) was reduced (1.27 g/L vs 1.58). The FIBTEM MCF correlated linearly with the CF (r² = 0.68; p < 0.0001) and WBFC (r² = 0.65; p < 0.0001) in control blood but this relationship was maintained only with WBFC in CCHD blood. Model high HCT blood showed abnormal ROTEM test results that were similar to CCHD blood, including reduced FIBTEM MCF (14 mm with HCT 0.32-0.44 vs 6 mm with HCT 0.63-0.70). The ROTEM results were HCT dependent but independent of plasma clotting times and fibrinogen concentration.

Conclusion

Supra-physiologic HCT causes abnormal ROTEM test results consistent with increased dilution of fibrinogen and coagulation factors in whole blood by red cells. High HCT should be considered during interpretation of ROTEM test results in clinical settings.     

Significant motor improvement in an infant with congenital heart disease and a rolandic stroke: The impact of early intervention

Objective: To report the impact of early motor intervention in an infant with congenital heart disease (CHD) and a stroke. Methods and Results: A 35-week newborn with a complex CHD and a normal MRI presented with early motor developmental delay at 2 months. She began an intervention program, which included biweekly motor developmental therapy with a physiotherapist, parental education, and daily home exercises. At 4 months, she underwent cardiac surgery. Following surgery, she was diagnosed with a stroke involving the right sylvian artery territory. She continued her intensive intervention program. The 12-month assessment revealed an evident gain of motor function. Despite MRI evidence of a chronic infarct involving the primary motor cortex, the child had normal motor functions. Conclusion: This case report supports the positive impact of early intervention in infants with CHD and its potential effect on enhancing neuroplasticity, even in children with cerebro-vascular accidents involving areas of motor function.     

Elimination of central sleep apnea by cardiac valve replacement: a continuous follow-up study in patients with rheumatic valvular heart disease

BackgroundRecent studies have suggested that cardiac surgery may affect sleep-disordered breathing (SDB) in chronic heart failure patients. However, the dynamic changes in sleep apnea and heart function after cardiac surgery and the mechanisms responsible for these changes remain unknown.MethodsPatients with rheumatic valvular heart disease (RVHD) and SDB were enrolled and followed up at three, six and 12 months after cardiac valve replacement (CVR). Baseline and follow-up clinical data consisting of NYHA classification, 6 min walk distance (6-MWD), medications, echocardiography, electrocardiography, chest X-ray, arterial blood gas, lung-to-finger circulation time (LFCT), and sleep data were collected and evaluated.ResultsTwenty-four central sleep apnea (CSA) patients and 15 obstructive sleep apnea (OSA) patients completed three follow-up assessments. Comparison of the baseline parameters between OSA patients and CSA patients showed that CSA patients had a worse baseline cardiac function assessed by higher NYHA class, shorter 6-MWD, larger left atrial diameter, longer LFCT, and enhanced chemosensitivity (higher pH and lower arterial carbon dioxide tension (PaCO₂)). A continuous significant elevation in 6-MWD and left ventricular ejection fraction and decrease in NYHA class, plasma BNP, and left atrial diameter were found in both CSA and OSA patients. When comparing CSA and OSA patients, the CSA indices were remarkably reduced at month 3 post CVR and sustained throughout the trial, whereas there were no significant decreases in OSA index and hypopnea index. pH values and LFCT were markedly decreased and PaCO₂ markedly increased in patients with CSA at the end of the third months following CVR. These changes were sustained until the end of the trial.ConclusionsCSA patients with RVHD had a worse baseline cardiac function, enhanced chemosensitivity and disordered hemodynamic as compared with OSA patients with RVHD. CSA were eliminated after CVR; however, there were no changes in OSA. The elimination of CSA, post CVR, is associated with the combined efficacies of improvement of cardiac function, normalized chemosensitivity, and stabilized hemodynamic.     

Application of the Type D Scale (DS14) in Chinese coronary heart disease patients and healthy controls

Objective

To examine the psychometric properties of the Type D Scale (DS14) in mainland China.

Methods

One hundred and seventy-eight coronary heart disease (CHD) patients and 376 healthy controls were recruited. They completed the Chinese version of the DS14, the Zung Self-Rating Depression Scale, the Positive Affect and Negative Affect Scale, the Perceived Social Support Scale, and the Social Avoidance and Distress Scale. Thirty-five of the patients were also rated by their family members on the DS14.

Results

The two-factor structure of the DS14 was replicated. The Cronbach's α coefficients for the negative affectivity (NA) and social inhibition (SI) subscales were 0.90 and 0.85, respectively, for the CHD patients and 0.87 and 0.69, respectively, for the healthy subjects. The correlations between the self-reports and the observer ratings (r_NA=0.56, r_SI=0.69) supported satisfactory consensual validity. Good convergent validity was shown by the expected correlations and the scale-level factor analyses of NA with depression and negative affect, and SI with perceived social support and social avoidance and distress. With the standardized cut-off of NA ≥10 and SI ≥10, 31.4% of the CHD patients and 31.9% of the healthy controls in China were defined as having a Type D personality.

Conclusions

The results indicate that the Type D construct is valid and reliable in Chinese populations. The Chinese version of the DS14 shows good psychometric properties. The prevalence of Type D personality in China falls within the range of what has been found in Western countries, at least for CHD patients. This study indicates that it is possible to use the DS14 among Chinese populations in future cross-cultural studies.     

A new automated implementation of the Posturo-Locomotion-Manual (PLM) method for movement analysis in patients with parkinson's disease

Zackrisson T, Holmberg B, Johnels B, Thorlin T. A new automated implementation of the Posturo‐Locomotion‐Manual (PLM) method for movement analysis in patients with parkinson’s disease.
Acta Neurol Scand: 2011: 123: 274–279.
© 2010 John Wiley & Sons A/S. Objective – The Posturo‐Locomotion‐Manual (PLM) test, which uses an optoelectronic laboratory system, has here been further developed into an automated, more user‐friendly, standardized tool for movement analysis named the QbTestMotus. This paper compares the accuracy of QbTestMotus to the PLM test, in particular the automated data analysis. Methods – Both QbTestMotus and the PLM recorded data simultaneously from the same 61 patients. The correlation coefficients of movement time (MT), postural time (P), locomotion time (L), and manual time (M) were calculated between the systems. The absolute differences between the result parameters for each patient were also studied. Finally, the differences in MT between the systems were compared with the positive responses in the levodopa (L‐dopa) challenges as measured in the PLM test for 11 patients. Results – The comparisons in all the 61 patients showed high correlation coefficients for all four parameters. The absolute differences between the parameters were small and had small standard deviations, and the decreases in MT because of L‐dopa in the positive L‐dopa responders were much larger than the absolute difference between the systems. Conclusion – The PLM test and QbTestMotus are equivalent along all parameters, thus indicating that the test quality is equivalent between the PLM test and the automated QbTestMotus system.     

Decreased serum amyloid beta(1-42) autoantibody levels in Alzheimer's disease, determined by a newly developed immuno-precipitation assay with radiolabeled amyloid beta(1-42) peptide.

BACKGROUND: Autoantibodies against amyloid beta (A beta) peptide found in patients with Alzheimer's disease (AD) also occur naturally in the general population independently of the cognitive status. METHODS: We compared serum A beta(1-42) autoantibody levels (A beta(1-42)-AL) of 96 AD patients and 30 healthy elderly control subjects (HC), assessing their diagnostic value for AD with a newly developed immunoprecipitation assay with radiolabeled A beta(1-42) peptide. RESULTS: We found a highly significant decrease of A beta(1-42)-AL in AD patients (p = .001) independently of age, cognitive status, and apolipoprotein E epsilon4 carrier status. Amyloid beta(1-42) autoantibody levels were correlated with gender in AD, with a higher level occurring in women. When A beta(1-42) autoantibody sensitivity (specificity) was set >80%, specificity (sensitivity) was below 50% to correctly allocate patients and healthy control subjects. CONCLUSIONS: Our data indicate a potentially pathophysiologic decrease of serum A beta(1-42) antibodies in AD. Amyloid beta(1-42) antibodies in the serum alone, however, seem not to be useful as a diagnostic marker of AD.     

Superficial vein thrombosis,thrombin generation and activated protein C resistance as predictors of thromboembolic events in lupus and antiphospholipid patients. A prospective cohort study

Introduction

Predicting thrombosis in patients with systemic lupus erythematosus (SLE) and/or antiphospholipid antibodies (aPL) is still challenging. Our objective was to determine risk factors for thrombotic events including activated protein C (APC) resistance proven by a thrombin generation (TG) assay in patients with SLE and/or aPL.

Materials and methods

We performed a prospective cohort study in a French University Hospital and tertiary care center. Ninety-two consecutive patients with SLE and/or aPL without ongoing anticoagulant treatment were enrolled. The outcome was time to thrombotic event. We evaluated clinical and laboratory variables including APC sensitivity ratio (APCsr) determined by TG. An APCsr > 90th percentile of a control population indicated APC resistance.

Results

Patients were followed-up for a median duration of 35 months (inter-quartile range: 26 to 62; 320 patient-years). Thrombosis during follow-up occurred in 18 patients. In univariate analysis, together with history of hypertension, superficial vein thrombosis (SVT) and arterial thrombosis, patients with both aPL and APC resistance had an increased risk for incident thromboembolic events (HR, 3.67[95% confidence interval, 1.31 to 10.31]). In multivariate analysis, only history of hypertension (HR, 10.77 [95% confidence interval, 3.15 to 36.83]), SVT (HR, 7.45 [95% confidence interval, 2.25 to 24.66]) and arterial thrombosis (HR, 3.31 [95% confidence interval, 1.14 to 9.55]) remained independent risk factors.

Conclusions

History of thrombosis including seemingly benign SVT have a higher predictive value for incident thrombotic events in SLE or aPL patients than APC resistance proven by TG.     

Stent implantation in the superficial femoral artery: Short thrombelastometry-derived coagulation times identify patients with late in-stent restenosis

Introduction

The mechanisms of restenosis, the recurrence of luminal narrowing, are complex and incompletely understood to date. Thrombin, the pivotal enzyme in haemostasis, presumably contributes to the formation of in-stent restenosis (ISR). It was therefore the aim of our study to investigate whether blood coagulation/thrombin generation plays a critical role in the formation of ISR in peripheral artery disease patients with stent angioplasty in the superficial femoral artery.

Materials and Methods

We aimed to examine in this retrospective study whether patients with high-degree restenosis (50-75% lumen diameter reduction, n = 20) are in a hypercoaguable state implying enhanced readiness to generate thrombin compared to patients with low-degree restenosis (< 50% lumen diameter reduction, n = 14).

Results

The coagulation tests calibrated automated thrombography, activated partial thromboplastin time, platelet aggregation, platelet adhesion, fibrinogen, and microparticles’ procoagulant activity did not indicate a different coagulation status in the two patient groups. However, the thrombelastometry-derived value Coagulation Time (CT) was significantly shorter in the high-degree restenosis group (p = 0.012), indicating a hypercoagulable state of patients with high-degree restenosis. Under our experimental conditions, CTs shorter than 444.5 s identify patients at high risk (sensitivity = 95%) for luminal narrowing.

Conclusions

Our study supports the assumption that blood coagulation/thrombin generation plays a critical role in the development of ISR in peripheral arteries after stent insertion and that the thrombelastometry-derived CT might be a suitable value to identify peripheral artery disease patients at risk for development of high-degree in-stent restenosis in the superficial femoral artery.