Novel characteristics of soluble fibrin: hypercoagulability and acceleration of blood sedimentation rate mediated by its generation of erythrocyte-linked fibers.

Soluble fibrin (SF) in blood consists of monomers lacking both fibrinopeptides A with a minor population in multimeric clusters. It is a substantial component of isolated fibrinogen (fg), which spontaneously self-assembles into protofibrils progressing to fibers at sub-physiologic temperatures, a process enhanced by adsorption to hydrophobic and some metal surfaces. Comparisons of SF-rich (FR) and SF-depleted (FD) fg isolates disclosed distinct molecular imprints of each via an adsorption/desorption procedure using gold surfaced silica microplates. Accelerated plasminogen activator-induced lysis and decreased stiffness (G') of thrombin-induced FR fg clots were revealed by thomboelastography. Erythrocyte sedimentation (ESR) in afibrinogenemic plasma (Hematocrit 25-33%) was accelerated by FR fg nearly threefold that of FD fg. Stained smears disclosed frequent rouleaux formations and fibers linking stacked erythrocytes in contrast to no rouleaux by FD fg. Rouleaux formations were more pronounced at 4 °C than at ambient temperatures and at fiber-membrane contacts displayed irregular, knobby membrane contours. One of several FR fg isolates also displayed incomplete fiber networks in cell-free areas. What is more, pre-mixing FR fg with each of three monoclonal IgG anti-fg antibodies at 1.5 mol/mol fg, that inhibited fibrin polymerization, prevented rouleaux formation save occasional 2-4 erythrocyte aggregates. We conclude that spontaneously generated SF fibers bound to erythrocytes forming intercellular links culminating in rouleaux formation and ensuing ESR acceleration which in clinical settings reflects hypercoagulability. Also, the results can explain the reported fg binding to erythrocytes via ligands such as CD47, stable in vivo RBC aggregates in capillaries, and red areas of pathologic thrombi.

Do coagulation or fibrinolysis reflect the disease condition in patients with soft tissue sarcoma?

BACKGROUND: Coagulation and fibrinolysis are distinct processes that are highly correlated. Cells control coagulation and fibrinolysis by expression of tissue factor and urokinase-type plasminogen activator receptor on their surface. Tumor cells express these proteins, adjust their microenvironment and induce tumor exacerbation. We hypothesized that the expression of plasma markers for coagulation and fibrinolysis in patients with soft tissue sarcomas (STSs) was dependent on the level of tumor malignancy. To elucidate which markers are predictive of recurrence, metastasis and prognosis, coagulation or fibrinolysis, we analyzed the correlation between plasma levels of thrombin-antithrombin III complex (TAT), soluble fibrin (SF), plasmin-α2 plasmin inhibitor complex (PIC), D-dimer (DD) and clinical parameters in patients with STSs. METHODS: TAT, SF, PIC or DD were measured in pre-treatment blood samples from 64 patients with primary STSs and analyzed with clinicopathological parameters, and 5-year recurrence free survival (RFS), 5-year metastasis free survival (MFS) and 5-year overall survival (OS) were evaluated. RESULTS: The metastasis group had significantly higher DD (p = 0.0394), PIC (p = 0.00532) and SF (p = 0.00249) concentrations than the group without metastasis. The group that died of disease showed significantly higher DD (p = 0.00105), PIC (p = 0.000542), SF (p = 0.000126) and TAT (p = 0.0373) than surviving patients. By dividing the patients into low and high groups, the group with high DD, PIC, SF and TAT showed significantly lower 5-year MFS and 5-year OS than the corresponding low group. Furthermore, in multivariate COX proportional hazard analysis of continuous variables for 5-year MFS, only PIC was found to be a significant factor (HR: 2.14). CONCLUSION: Fibrinolysis was better than coagulation at reflecting the disease condition of patients with STS. Notably, PIC levels ≥ 1.1 can not only predict the risk of metastasis and poor prognosis, but also increasing PIC levels correspond to further increases in risks of metastasis and poor prognosis.

Significance of coagulation and fibrinolysis markers for benign and malignant soft tissue tumors.

BACKGROUND: The intimate relationship between coagulation and fibrinolysis in malignant tumors is a well-known phenomena, with the malignant phenotype enhancing coagulation and fibrinolysis. We hypothesized that soft tissue sarcoma (STS) affects the expression of coagulation and fibrinolysis markers, which could be used to distinguish STS from benign soft tissue tumors. We analyzed the correlations between plasma levels of D-dimer (DD), plasmin-α2 plasmin inhibitor complex (PIC), soluble fibrin (SF), and thrombin-antithrombin III complex (TAT) in benign soft tissue tumors and STS to elucidate whether these markers can be used to predict STS. METHODS: Plasma DD, PIC, SF and TAT levels in primary soft tissue tumors (benign 67, STS 68) were measured before biopsy or treatment. The marker levels were analyzed and compared to various clinicopathological parameters. RESULTS: In malignancy (STS), the average DD, PIC and SF levels were significantly higher than in benign tumors. Multivariate logistic analysis of continuous variables indicated that only PIC exhibited a significant difference (OR: 24.5, 95%CI: 3.55-170, p = 0.0012). Receiver operating characteristic curve analysis produced area under the curve values for DD: 0.691, PIC: 0.784, SF: 0.734 and TAT: 0.588. Youden's index was used to establish thresholds of 0.37 (DD), 0.80 (PIC), 0.90 (SF) and 0.82 (TAT). Threshold values for PIC and SF indicated high specificity (0.881, 0.791) and high positive predictive value (0.818, 0.745), respectively. The highest accuracy value among the markers was observed for PIC (0.704). Significant differences in multivariate analysis of binary variables were demonstrated by categorizing low and high groups based on their threshold, PIC (≥0.80) (OR: 3.36, 95%CI: 1.19-9.43, p = 0.0212) and SF (≥0.90) (OR: 2.63, 95%CI: 1.04-6.66, p = 0.0404) . CONCLUSIONS: Of the coagulation and fibrinolysis markers studied, increased PIC levels were related to STS and over 0.80 PIC was the most suitable for the prediction of STS, which, along with other diagnostic tools, represents a helpful subsidiary tool for the prediction of STS.

A Prospective Multicenter Observational Study of Venous Thromboembolism after Gastric Cancer Surgery (SHISA-1601).

INTRODUCTION: This study aimed to clarify the frequency and risk factors of intercurrent venous thromboembolism (VTE) in patients undergoing major curative gastric cancer surgery. METHODS: This prospective, multicenter, observational study included patients with gastric cancer who underwent radical gastrectomy at 5 hospitals between June 2016 and May 2018. Patients who were preoperatively administered anticoagulants were excluded. RESULTS: A total of 126 patients were eligible to participate. VTE occurred within 9 days postoperatively in 5 cases (4.0%; 2 symptomatic and 3 asymptomatic). Postoperative day (POD) 1 plasma D-dimer and soluble fibrin (SF) levels were significantly higher in the VTE group than in the non-VTE group. Receiver-operating characteristic curve (ROC) analysis indicated a statistically significant ability of POD 1 D-dimer and SF levels to predict postoperative VTE development after gastrectomy; this finding was reflected by an area under the curve (AUC) of 0.97 (95% CI 0.92-1.0) and 0.87 (95% CI 0.74-1.0), respectively. Cutoff values of D-dimer (24.6 µg/mL) and SF (64.1 µg/mL) were determined. Intraoperative blood transfusion (odds ratio [OR] 7.86), POD 1 D-dimer ≥24.6 µg/mL (OR 17.35), and POD 1 SF ≥64.1 µg/mL (OR 19.5) were independent predictive factors for postoperative VTE (p < 0.05). CONCLUSION: VTE occurred in 4.0% patients (1.6% symptomatic and 2.4% asymptomatic) after gastric cancer surgery; however, with an early diagnosis and anticoagulant therapy, no patients experienced progression. Careful observation of patients with a high risk for VTE, including intraoperative blood transfusion and high POD 1 D-dimer or SF levels, would contribute to the early detection of VTE.

Case of adenomyosis causing the activation of the coagulation system after a complete loss of endometrium following microwave endometrial ablation.

The formation of microbleed and minute tissue necrosis inside adenomyosis after the shedding of endometrial or endometrial-like tissue within the myometrium during menstruation is receiving attention as a new pathological condition of uterine adenomyosis. These formations might greatly affect coagulation and fibrinolysis function. However, these modulations might occur due to indirect effects of massive hemorrhage from the uterus with adenomyosis. We present a case of adenomyosis in which the patient's coagulation system was markedly activated despite the absence of menstruation due to previous microwave endometrial ablation to prevent massive uterine hemorrhage. Although no uterine bleeding was observed at all, the patient's serum levels of thrombin-antithrombin complex and soluble fibrin were abnormally elevated at the time when she complained of lower abdominal pain. As the first such case in the world, the present case is valuable for showing that the coagulation function can be modified by uterine adenomyosis.

RELATIONSHIP BETWEEN PRE- AND POST-THROMBOSIS FACTORS IN PATIENTS WITH STAGE VD CKD TREATED BY LONG-TERM HEMODIALYSIS.

OBJECTIVE: The aim: To determine informative value of pre-thrombosis, post-thrombosis and anticoagulation factors as well as their correlations for assessment of hemostasis status in patients with stage VD CKD. PATIENTS AND METHODS: Materials and methods: Potential predictors of thrombophilia development as well as their relationships depending on the level of molecular markers of hemostasis were studied in 88 patients with stage VD CKD undergoing long-term hemodialysis with the view to determine their informative value. RESULTS: Results: Accumulation of soluble fibrin (sF) was demonstrated to cause moderate reaction of D-dimer (D-d) being insufficient in the absence of reaction of anticoagulant component of hemostasis. Soluble fibrin levels were found to be associated with D-d concentration (r = 0.39) and functionally inactive prothrombin forms (FIPF) to some extent (r = -0.24). Accumulation of FIPF in individuals with high level of sF implies significant activation of blood coagulation system at the stage prior to thrombin formation. Absence of close relationship between pre- and post-thrombosis indices may be indicative of still preserved potential of anticoagulant component of hemostasis. CONCLUSION: Conclusions: Accumulation of FIPF is an early marker of activation of blood coagulation and possible thrombosis. Levels of sF correlate with pre-thrombosis (fibrinogen, FIPF) and post-thrombosis (D-d) factors being associated with inhibition of anticoagulation processes. Comprehensive study of basic components of hemostasis in patients with VD stage of chronic kidney disease offer broader opportunities in arranging prophylactic measures to prevent thrombophilia.

Soluble Fibrin Monomer Complex and Prediction of Cardiovascular Events in Atrial Fibrillation: The Observational Murcia Atrial Fibrillation Project.

BACKGROUND: Soluble fibrin monomer complex (SFMC) is a biomarker of fibrin formation abnormally elevated in clinical situations of hypercoagulability. OBJECTIVE: We investigated the association and predictive performance of SFMC for stroke, adverse cardiovascular events, cardiovascular mortality and all-cause mortality in a cohort of patients with atrial fibrillation (AF) receiving vitamin K antagonist (VKA) anticoagulant therapy. DESIGN: During the second semester of 2007, we included 1226 AF outpatients stable on VKAs (INR 2.0-3.0) over a period of 6 months. SFMC levels were assessed at baseline. During 6.5 (IQR 4.4-8.0) years of follow-up, we recorded all ischemic strokes, adverse cardiovascular events (composite of stroke, acute heart failure, acute coronary syndrome and cardiovascular death), cardiovascular deaths and all-cause deaths. PARTICIPANTS: All patients were recruited consecutively. We excluded patients with rheumatic mitral valves, prosthetic heart valves, acute coronary syndrome, stroke, hemodynamic instability, hospital admissions or surgical interventions within the preceding 6 months. MAIN MEASURES: SFMC levels were measured in plasma by immunoturbidimetry in an automated coagulometer (STALiatestFM, Diagnostica Stago, Asnieres, France). KEY RESULTS: We recorded 121 (1.52%/year) ischemic strokes, 257 (3.23%/year) cardiovascular events, 67 (0.84%/year) cardiovascular deaths and 486 (6.10%/year) all-cause deaths. SFMC >12 µg/mL was not associated with stroke but was associated with higher risk of cardiovascular events (HR 1.72, 95% CI 1.31-2.26), cardiovascular mortality (HR 2.16, 95% CI 1.30-3.57) and all-cause mortality (HR 1.26, 95% CI 1.03-1.55). When SFMC >12 µg/mL was added to the CHA2DS2-VASc, there were significant improvements in predictive performance, sensitivity and reclassification for adverse cardiovascular events (c-index: 0.645 vs. 0.660, p = 0.010; IDI = 0.013, p < 0.001; NRI = 0.121, p < 0.001) and cardiovascular mortality (c-index: 0.661 vs. 0.691, p = 0.006; IDI = 0.009, p = 0.049; NRI = 0.217, p < 0.001), but decision curves demonstrated a similar net benefit and clinical usefulness. CONCLUSIONS: In AF patients taking VKAs, high SFMC levels were associated with the risk of adverse cardiovascular events, cardiovascular mortality and all-cause mortality. The addition of SFMC to the CHA2DS2-VASc score improved its predictive performance for these outcomes, but failed to show an improvement in clinical usefulness.

The role of soluble fibrin during anticoagulant therapy: a case report.

Warfarin, dabigatran, and apixaban are used for preventing ischemic stroke due to non-valvular atrial fibrillation (NVAF). However, it is often challenging to select the appropriate anticoagulant. We present the case of a 70-year-old male patient with persistent NVAF who developed pulmonary thromboembolism (PTE), deep vein thrombosis (DVT), and left atrial thrombus during anticoagulant therapy with warfarin. Intravenous recombinant tissue plasminogen activator was administered during his acute PTE. Heparin and apixaban were administered over 28 days; heparin was discontinued after the DVT resolved, while apixaban was administered to prevent ischemic stroke. Two days after heparin was discontinued, the patient experienced an ischemic stroke. Dabigatran was administered for secondary ischemic stroke prevention. Soluble fibrin (SF) levels remained elevated during treatment with heparin and apixaban and returned to normal after apixaban was replaced with dabigatran. Monitoring of SF may be useful as an index for selection of anticoagulants.

Changes in blood coagulation-fibrinolysis markers by pneumatic tourniquet during total knee joint arthroplasty with venous thromboembolism.

This study investigated changes in blood coagulation-fibrinolysis markers during total knee arthroplasty (TKA). Preoperative 16-row multidetector row computed tomography (MDCT) revealed no asymptomatic venous thromboembolism (VTE) in the 42 patients recruited. Using MDCT postoperatively, patients were divided into thrombus (asymptomatic VTE, 19 patients) and no-thrombus (23 patients) groups. Blood taken at intervals before and after pneumatic tourniquet release revealed increased plasminogen activator inhibitor type-1 (PAI-1) at 30s for both groups and at 90s (both P=0.01) in the thrombus group. D-dimer levels were highest at 30 and 90s for both groups (P = 0.01). PAI-1 and D-dimer levels were strongly correlated at both time points in the thrombus group. Inactivating fibrinolysis due to PAI-1 may lead to asymptomatic VTE after TKA.

Selective pharmacological prophylaxis based on individual risk assessment using plasma levels of soluble fibrin and plasminogen-activator inhibitor-1 following total hip arthroplasty.

OBJECTIVES: The purpose of this prospective study was to evaluate the utility of preferential application of pharmacoprophylaxis based on the quantitative evaluation by soluble fibrin (SF) and plasminogen activator inhibitor-1 (PAI-1) analysis on the day after total hip arthroplasty (THA). METHODS: A hundred and sixteen patients were enrolled. High-risk patients were defined as those with elevated levels of SF or PAI-1, beyond their cut-off values, on the day after THA. For high-risk patients, fondaparinux was administered for 10 days postoperatively. When both plasma levels of SF and PAI-1 were less than their cutoff levels, the patients were regarded to be at low risk. For low-risk patients, only mechanical prophylaxis was applied. RESULTS: Sixty patients (52%) were considered to be at high risk. Among them, venous thromboembolism (VTE) was detected in five patients (8%) by CT angiography. In addition, there were four patients (3%) who developed bleeding complications. Fifty-six patients (48%) were considered to be at low risk, and only one patient (2%) developed VTE. CONCLUSION: The measurement of SF and PAI-1 levels on the day after surgery may be helpful to identify the individual risk for postoperative VTE. According to this evaluation, a half of patients might not need to administer anticoagulant agents following surgery.

Current Clinical Practice of Laboratory Testing of the Hemostasis and Coagulation System in Patients with Sepsis: A Nationwide Observational Study in Japan.

Introduction: The clinical benefit of hemostasis molecular indicators such as thrombin-antithrombin complex (TAT), soluble fibrin (SF), and prothrombin fragment 1 + 2 (F1+2) for the diagnosis of disseminated intravascular coagulation (DIC) is reported. Recently, novel DIC diagnostic criteria that adopt them were proposed in Japan. Despite the theoretical understanding of their function, the practical use of these markers remains unclear. The present study aimed to provide a descriptive overview of current clinical practice regarding the measurement of hemostasis markers in sepsis management in Japan. Methods: This retrospective observational analysis used the Japanese Diagnosis Procedure Combination inpatient database containing data from more than 1500 acute-care hospitals in Japan. We identified adult patients hospitalized for sepsis between April 2018 and March 2021. Descriptive statistics for measuring several hemostasis laboratory markers were summarized using patient disease characteristics, hospital characteristic, and geographical location. Results: This study included 153,474 adult sepsis patients. Crude in-hospital mortality was 30.0%. Frequency of measurement of fibrinogen, fibrin degradation products (FDP), and D-dimer in sepsis patients on admission was 43.2%, 36.1%, and 46.4%, respectively. Novel and specific hemostasis molecular markers such as TAT, SF, and F1+2 were seldom measured (1.9%, 1.7%, and 0.02%, respectively). Hemostasis molecular markers were more frequently measured with progression of thrombocytopenia. Measurement of these clinically favorite hemostasis markers was influenced not only by disease characteristics but also hospital characteristic or geographical location. Conclusions: Hemostasis molecular markers such as TAT, SF, and F1+2 were rarely measured in clinical settings. Although adopted by several DIC scoring systems, neither fibrinogen, FDP, nor D-dimer was routinely measured.

Plasma Soluble Fibrin Is Useful for the Diagnosis of Thrombotic Diseases.

BACKGROUND: Soluble fibrin (SF) is a form of fibrinogen that is activated by thrombin and is considered to be useful for the diagnosis of the prethrombotic state or thrombosis. METHODS: Plasma levels of fibrin-related markers (FRMs), such as SF, D-dimer, fibrinogen, and fibrin degradation prioduct (FDP) levels in critically ill patients, were examined for the diagnosis of disseminated intravascular coagulation (DIC), venous thromboembolism (VTE), peripheral arterial thromboembolism (PATE), acute myocardial infarction (AMI), and acute cerebral infarction (ACI). RESULTS: FRMs showed the usefulness in diagnosing DIC and VTE and the cutoff values of D-dimer, FDP, and SF for DIC were 7.2-7.8 µg/mL, 10.0 µg/mL, and 9.5 µg/mL, respectively. The cutoff values of D-dimer and FDP for VTE were similar to the 97.5th percentile values of healthy volunteers, while the cutoff value of SF was 6.9 µg/mL. In AMI and ACI, the cutoff values of D-dimer and FDP were lower than the 97.5 percentile values of healthy volunteers. A receiver operating characteristic analysis for all thrombosis cases showed that an adequate cutoff value in only SF among FRMs was higher than the confidence interval of healthy volunteers. Only SF had high sensitivity for thrombosis, as the FDP/SF ratio was markedly low for ACI, AMI and VTE. CONCLUSIONS: FRMs, especially D-dimer and FDP, were useful for diagnosing thrombosis with hyperfibrinolysis (e.g., DIC). As SF showed high sensitivity for predominantly thrombotic diseases, including arterial thrombosis, such as ACI and AMI, a high SF value suggests the possibility of an association with thrombosis. Finally, SF is the most useful marker for raising suspicion of an association with thrombosis, especially arterial thrombosis.

Efficacy of Coagulofibrinolytic Markers for Postoperative Prediction of Venous Thromboembolism in Colorectal Surgery Patients: A Retrospective Observational Study.

Objectives: A low rate of the incidence of venous thromboembolism (VTE) after surgeries that are preoperatively classified as having high risk of VTE has been reported in recent years. We seek to identify the optimal cases to receive perioperative pharmacologic thromboprophylaxis. In this study, we evaluated the incidence rate of VTE among patients undergoing colorectal surgery who did not receive perioperative pharmacologic thromboprophylaxis, and the ability of coagulofibrinolytic markers to predict the postoperative development of VTE. Methods: We retrospectively analyzed the rate of postoperative development of VTE in 70 patients undergoing elective colorectal surgery without perioperative pharmacologic thromboprophylaxis and the ability of coagulofibrinolytic markers to predict the development of VTE. Results: The incidence of VTE was observed in 11 patients (15.7%); all cases were asymptomatic and distal-type deep vein thrombosis (DVT). Comparisons of time course changes in perioperative coagulofibrinolytic markers between patients with and without DVT revealed significant differences in soluble fibrin (SF), thrombin-antithrombin complex (TAT), fibrin/fibrinogen degradation product (FDP) and D-dimer. Dynamic postoperative physiological coagulofibrinolytic responses were shown, but all four markers at each postoperative point demonstrated moderate accuracy (median area under the curve [AUC]: 0.788, median sensitivity: 0.865, median specificity: 0.644) for predicting the development of DVT. Conclusions: The incidence of postoperative VTE was low in patients with colorectal surgery even in those who did not receive perioperative pharmacologic thromboprophylaxis. SF, TAT, FDP and D-dimer were useful for predicting the development of DVT when we set cut-off values taking the physiological perioperative coagulofibrinolytic responses into consideration.

Association of antithrombin with development of trauma-induced disseminated intravascular coagulation and outcomes.

Introduction: Trauma activates the innate immune system to modulate hemostasis and minimize the damage caused by physiological bodily responses, including the activation of coagulation. Sufficiently severe trauma overwhelms physiological responses and elicits the systemic inflammatory response syndrome, which leads to the onset of disseminated intravascular coagulation (DIC), characterized by dysregulated inflammatory coagulofibrinolytic responses. Impaired anticoagulant mechanisms, including antithrombin, constitutes the pathology of DIC, while the dynamics of antithrombin and relevance to outcomes in trauma-induced coagulopathy have not been fully elucidated. This study investigated the associations of antithrombin activity with DIC onset and outcomes in severely injured patients. Methods: This retrospective sub-analysis of a multicenter, prospective study included patients with an injury severity score ≥16. We characterized trauma patients with low antithrombin activity (antithrombin <80% on hospital arrival, n = 75) in comparison with those who had normal antithrombin activity (antithrombin ≥80%, n = 200). Global markers of coagulation and fibrinolysis, molecular biomarkers for thrombin generation (soluble fibrin [SF]), and markers of anticoagulation (antithrombin) were evaluated to confirm the associations of antithrombin with DIC development and outcomes, including in-hospital mortality and the multiple organ dysfunction syndrome (MODS). Results: Patients with low antithrombin activity had higher prevalence of shock, transfusion requirements, and in-hospital mortality. Higher DIC scores and more severe organ dysfunction were observed in the low AT group compared to that in the normal AT group. Antithrombin activity on arrival at the hospital was an independent predictor of the development of DIC in trauma patients, and levels of SF increased with lower antithrombin values (antithrombin activity > 85%). Antithrombin activity at 3 h showed good predictive performance for in-hospital mortality, and a multivariable Cox proportional-hazard regression model with a cross-product term between the antithrombin and DIC showed that the in-hospital mortality in patients with DIC increased with decreased antithrombin activity. A multivariable logistic regression model showed that the odds for the development of MODS in patients with DIC increased with lower antithrombin values. Conclusion: Decreased antithrombin activity in trauma-induced coagulopathy is associated with poor outcomes through worsening of DIC.

Asymptomatic Venous Thromboembolism After Hepatobiliary-Pancreatic Surgery: Early Detection Using D-dimer and Soluble Fibrin Monomer Complex Levels.

AIM: The aim was to investigate the usefulness of a preemptive management strategy that includes monitoring serum D-dimer (DD) and soluble fibrin monomer complex (SFMC) levels for early detection and treatment of venous thromboembolism (VTE) after hepatobiliary-pancreatic (HBP) surgery. METHODS: Overall, 678 patients who underwent HBP surgery between January 2010 and March 2020 were enrolled. Patients with increased postoperative serum DD or SFMC levels underwent contrast-enhanced computed tomography, and those with VTE received anticoagulant agents. The VTE risk factors were investigated using multivariable analysis. Postoperative changes in DD and SFMC levels were verified, and their ability to identify VTE was evaluated using receiver operating characteristic (ROC) analysis. RESULTS: VTE developed in 83 patients (12.2%), and no symptomatic VTE or death due to VTE was observed. Multivariable analysis identified female sex (odds ratio [OR] 2.26; 95% confidence interval [CI] 1.41-3.60; P < .001) and surgery duration of ≥401 min (OR 2.07; 95% CI 1.27-3.35; P < .001) as independent risk factors for VTE. Maximum serum DD and SFMC levels in patients who developed VTE were significantly higher than those in patients without VTE (DD, 15.1 vs 8.9 µg/mL, P < .001; SFMC, 18.0 vs 10.2 µg/mL, P < .001, respectively). Both DD (n = 678) and the combination of DD and SFMC levels (n = 230) showed a good ability to detect VTE (area under the ROC curve, 0.804 and 0.761, respectively). CONCLUSION: Our preemptive strategy of monitoring serum DD and SFMC levels enables early detection and treatment intervention of VTE after HBP surgery.

Fibrin Strands Will Grow from Soluble Fibrin and Hang Up in an In Vitro Microcirculatory Viscoelastic Model: Is This a Major Cause of COVID-19 Associated Coagulopathy?

Viscoelastic testing (VET) by both TEG and ROTEM has demonstrated hypercoagulability early in corona virus disease 2019 (COVID-19) associated coagulopathy (CAC). Additional VET studies demonstrated fibrinolytic shutdown late in a majority of severely ill COVID-19 patients with an associated elevation of d-dimer. Elevated d-dimer confirms that coagulation, followed by fibrinolysis, has occurred. These findings imply that, during CAC, three enzymes-thrombin, Factor XIIIa and plasmin-must have acted in sequence. However, limitations in standard VET analyses preclude exploration of the earliest phases of clot induction, as well as clot formation and clot dissolution in flowing blood. Herein, we describe a novel method illuminating aspects of this unexplored area. In addition, we created an in vitro blood flow model in which the interactions of thrombin, Factor XIII and plasmin with fibrinogen can be studied, allowing the determination of soluble fibrin (SF), the highly unstable form of fibrin that precedes the appearance of a visible clot. This model allows the determination of the SF level at which fibrin microclots begin to form.

Fibers Generated by Plasma Des-AA Fibrin Monomers and Protofibril/Fibrinogen Clusters Bind Platelets: Clinical and Nonclinical Implications.

Objective Soluble fibrin (SF) is a substantial component of plasma fibrinogen (fg), but its composition, functions, and clinical relevance remain unclear. The study aimed to evaluate the molecular composition and procoagulant function(s) of SF. Materials and Methods Cryoprecipitable, SF-rich (FR) and cryosoluble, SF-depleted (FD) fg isolates were prepared and adsorbed on one hydrophilic and two hydrophobic surfaces and scanned by atomic force microscopy (AFM). Standard procedures were used for fibrin polymerization, crosslinking by factor XIII, electrophoresis, and platelet adhesion. Results Relative to FD fg, thrombin-induced polymerization of FR fg was accelerated and that induced by reptilase was markedly delayed, attributable to its decreased (fibrinopeptide A) FpA. FR fg adsorption to each surface yielded polymeric clusters and co-cryoprecipitable solitary monomers. Cluster components were crosslinked by factor XIII and comprised ≤21% of FR fg. In contrast to FD fg, FR fg adsorption on hydrophobic surfaces resulted in fiber generation enabled by both clusters and solitary monomers. This began with numerous short protofibrils, which following prolonged adsorption increased in number and length and culminated in surface-linked three-dimensional fiber networks that bound platelets. Conclusion The abundance of adsorbed protofibrils resulted from (1) protofibril/fg clusters whose fg was dissociated during adsorption, and (2) adsorbed des-AA monomers that attracted solution counterparts initiating protofibril assembly and elongation by their continued incorporation. The substantial presence of both components in transfused plasma and cryoprecipitate augments hemostasis by accelerating thrombin-induced fibrin polymerization and by tightly anchoring the resulting clot to the underlying wound or to other abnormal vascular surfaces.

The Usefulness of the Combination of D-Dimer and Soluble Fibrin Monomer Complex for Diagnosis of Venous Thromboembolism in Psychiatric Practice: A Prospective Study.

PURPOSE: D-dimer has the advantage of excluding venous thromboembolism (VTE) due to its high sensitivity but is disadvantageous for diagnosing VTE due to its low specificity. A method to increase the usefulness of D-dimer in the diagnosis of VTE is warranted. This study aimed to investigate the usefulness of the combination of D-dimer and soluble fibrin monomer complex (SFMC), which has been suggested as a new candidate marker for VTE, in VTE diagnosis. PATIENTS AND METHODS: This prospective study in 109 subjects was performed at a psychiatric department between August 1, 2017 and December 31, 2019. Subjects' levels of D-dimer and SFMC were measured simultaneously. Plasma levels of D-dimer and SFMC were measured using NANOPIA® D-dimer and NANOPIA® SF. Subjects with positive D-dimer (≥1.0 µg/mL) results underwent contrast computed tomography for confirmation of VTE within 12 hours of D-dimer measurement. A receiver operating characteristic curve analysis was performed to examine the usefulness of SFMC for the diagnosis of VTE. RESULTS: Only 109 of the 783 subjects without symptoms suggestive of VTE participated in the study. Out of 41 subjects with positive D-dimer results, 17 subjects were diagnosed with VTE. A receiver operating characteristic curve analysis was performed to determine cutoff values. The area under the curves was 0.848 for SFMC (p<0.001, 95% CI 0.722 to 0.974), and the optimal cutoff value was 10.0 µg/mL (sensitivity 58.8%, specificity 100%, positive predictive value 100%, negative predictive value 77.4%). CONCLUSION: SFMC was useful for diagnosing VTE in the psychiatric patients with positive D-dimer results.

Successful treatment for disseminated intravascular coagulation (DIC) corresponding to phenotype changes in a heat stroke patient.

BACKGROUND: Heat stroke induces coagulofibrinolytic activation, which leads to life-threatening disseminated intravascular coagulation (DIC). However, treatment strategies for DIC in heat stroke have not yet been established, and also, the time course changes in coagulofibrinolytic markers have not been thoroughly evaluated. We report a severe heat stroke case with DIC who was eventually saved by anti-DIC treatments in accordance with changes in coagulofibrinolytic markers. CASE PRESENTATION: A 45-year-old man was found unconscious outside, and his body temperature was elevated to 41.9 °C. For heat stroke, we performed an immediate tracheal intubation under the general anesthesia along with cooling by iced gastric lavage, cold fluid administration, and an intravascular cooling using Thermogard™. About 4 h after admission, his core temperature fell to 37 °C. We assessed coagulofibrinolytic biomarkers and treated in accordance with changes in these parameters. This case exhibited a biphasic change varying from an enhanced to a suppressed fibrinolytic type of DIC depending on the relative balance between fibrinolytic activation and the level of plasminogen activator inhibitor-1 (PAI-1). In the early phase with consumption coagulopathy and enhanced fibrinolysis, we transfused a large amount of fresh frozen plasma (FFP) and platelets with tranexamic acid, an antifibrinolytic agent, possibly providing relief for the bleeding tendency. Anticoagulant therapy using recombinant human thrombomodulin-α (rh-TM-α) and antithrombin III (ATIII) concentrate was especially effective for DIC with a suppressed fibrinolytic phenotype in the later phase, after which organ failure that included severe hepatic failure was remarkably improved. CONCLUSION: The present case may indicate the clinical significance of monitoring coagulifibrinolytic changes and the potential benefits of anticoagulants for heat stroke-induced DIC.

The Plasma Levels of ADAMTS-13, von Willebrand Factor, VWFpp, and Fibrin-Related Markers in Patients With Systemic Sclerosis Having Thrombosis.

This study aimed to examine the hemostatic abnormalities in patients with systemic sclerosis (SSc) and the relationship between these abnormalities and thrombotic events (THEs), focusing on the difference in diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc). The plasma levels of ADAMTS-13 (a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13), von Willebrand factor (VWF), VWF propeptide (VWFpp), d-dimer, and soluble fibrin (SF) were measured in 233 patients with SSc. The relationship between their levels and organ involvement, including THEs and interstitial lung disease (ILD), was evaluated. The plasma levels of VWF and VWFpp were significantly elevated and ADAMTS-13 activity was significantly decreased in patients with SSc compared to healthy participants. The VWFpp in dcSSc was significantly higher than in lcSSc. Twelve patients with SSc were complicated with acute THE, and 25 patients with SSc were complicated with past THE. The plasma levels of d-dimer and SF were significantly elevated in patients with SSc having THE. The plasma levels of VWF and VWFpp were significantly elevated in patients with SSc having ILD. The plasma levels of d-dimer were elevated in patients with SSc having other connective tissue diseases (CTDs). The plasma levels of ADAMTS-13 were significantly decreased and VWF, VWFpp, and SF were increased in patients with a d-dimer level of ≥1 µg/mL. Systemic sclerosis carries a high risk of THE, especially in patients with other CTDs. Plasma hemostasis-related markers are closely related to ILD and THE. These markers are important as markers of organ involvement as well as THE.