The neutralizing effect of heparin on blood-derived antimicrobial compounds: impact on antibacterial activity and inflammatory response.

Acting through a combination of direct and indirect pathogen clearance mechanisms, blood-derived antimicrobial compounds (AMCs) play a pivotal role in innate immunity, safeguarding the host against invading microorganisms. Besides their antimicrobial activity, some AMCs can neutralize endotoxins, preventing their interaction with immune cells and avoiding an excessive inflammatory response. In this study, we aimed to investigate the influence of unfractionated heparin, a polyanionic drug clinically used as anticoagulant, on the endotoxin-neutralizing and antibacterial activity of blood-derived AMCs. Serum samples from healthy donors were pre-incubated with increasing concentrations of heparin for different time periods and tested against pathogenic bacteria (Acinetobacter baumannii, Enterococcus faecium, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus) and endotoxins from E. coli, K. pneumoniae, and P. aeruginosa. Heparin dose-dependently decreased the activity of blood-derived AMCs. Consequently, pre-incubation with heparin led to increased activity of LPS and higher values of the pro-inflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6). Accordingly, higher concentrations of A. baumannii, E. coli, K. pneumoniae, and P. aeruginosa were observed as well. These findings underscore the neutralizing effect of unfractionated heparin on blood-derived AMCs in vitro and may lead to alternative affinity techniques for isolating and characterizing novel AMCs with the potential for clinical translation.

Perioperative management of venous recanalization in a patient with inherited antithrombin deficiency: case report.

Background: Inherited antithrombin (AT) deficiency (ATD) is a severe thrombophilia causing venous thromboembolism, which can be complicated by postthrombotic syndrome (PTS). Venous recanalization, used to treat PTS, often requires a temporary withdrawal of anticoagulant therapy. In ATD patients, there is a risk of insufficient perioperative anticoagulation due to altered heparin response. Key Clinical Question: There is no consensus on how to manage perioperative anticoagulation in ATD patients. Clinical Approach: Warfarin-unfractionated heparin transition could be a more reliable strategy than low-molecular-weight heparin transition because unfractionated heparin anti-Xa activity not only reflects heparin-bound AT but also AT's activity, which correlates strongly with therapeutic anticoagulation. Biological monitoring could thus decrease the number of plasma-derived AT supplementation. Conclusion: This study describes a successful perioperative management of anticoagulation for venous recanalization that could be suggested to type 1 ATD patients with PTS.

The effect of serum triglyceride levels and different lipid-lowering methods on the prognosis of hypertriglyceridemic acute pancreatitis: a single-center 12-year retrospective study by propensity score matching.

AIM: To investigate the impact of triglyceride on hypertriglyceridemic acute pancreatitis (HTG-AP) and different lipid-lowering methods on triglyceride-lowering efficiency and HTG-AP. METHODS: The patients with HTG-AP from January 2012 to December 2023 in Civil Aviation General Hospital were analyzed, retrospectively. Patients were divided and compared according to whether their triglycerides were below 5.56 mmol/L at 48 and 72 h of admission. The patients were divided into control group, insulin group, and low molecular weight heparin (LMWH)+bezafibrate group based on the different methods of lipid-lowering. Propensity score matching (PSM) was employed to balance the baseline characteristics. RESULTS: There was no correlation between the severity of HTG-AP and the triglyceride at admission. The incidence of severity, local complications, and persistent organ failure (POF) were significantly decreased in patients with 48-h and 72-h triglyceride attainment. Following PSM, the incidence of infectious pancreatic necrosis (IPN) (3.3% vs. 13.3%) was significantly reduced in insulin group compared with control group (p < .05). Compared with control group, LMWH + bezafibrate group had higher lipid reduction efficiency, and the incidence of IPN (0.9% vs. 10.1%) and POF (8.3% vs. 19.3%) was significantly decreased (p < .05). There was no significant difference in the efficiency of lipid-lowering, complications, and POF between LMWH + bezafibrate group and insulin group (p > .05). CONCLUSION: The severity of HTG-AP is not associated with the triglyceride levels at admission. However, rapid reduction of triglyceride levels can lower the incidence of local complications and respiratory failure. Compared with conservative treatment, insulin and LMWH + bezafibrate can both reduce the incidence of IPN in patients with HTG-AP.

Heparin-Modified Superparamagnetic Iron Oxide Nanoparticles Suppress Lithium Chloride/Pilocarpine-Induced Temporal Lobe Epilepsy in Rats through Attenuation of Inflammation and Oxidative Stress.

The development of antiepileptic drugs is still a long process. In this study, heparin-modified superparamagnetic iron oxide nanoparticles (UFH-SPIONs) were prepared, and their antiepileptic effect and underlying mechanism were investigated. UFH-SPIONs are stable, homogeneous nanosystems with antioxidant enzyme activity that are able to cross the blood-brain barrier (BBB) and enriched in hippocampal epileptogenic foci. The pretreatment with UFH-SPIONs effectively prolonged the onset of seizures and reduced seizure severity after lithium/pilocarpine (LP)-induced seizures in rats. The pretreatment with UFH-SPIONs significantly decreased the expression of inflammatory factors in hippocampal tissues, including IL-6, IL-1ß, and TNF-α. LP-induced oxidative stress in hippocampal tissues was in turn reduced upon pretreatment with UFH-SPIONs, as evidenced by an increase in the levels of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and a decrease in the level of lipid peroxidation (MDA). Moreover, the LP-induced upregulation of apoptotic cells was decreased upon pretreatment with UFH-SPIONs. Together, these observations suggest that the pretreatment with UFH-SPIONs ameliorates LP-induced seizures and downregulates the inflammatory response and oxidative stress, which exerts neuronal protection during epilepsy.

Postoperative anticoagulation management using subcutaneous unfractionated heparin for a patient with nonbacterial thrombotic endocarditis: a case report.

Nonbacterial thrombotic endocarditis (NBTE) presents nonbacterial vegetation on cardiac valves. NBTE requires appropriate anticoagulant therapy to prevent recurrence after surgery. However, there has not yet been established evidence for anticoagulant therapy in NBTE, and low molecular weight heparin is not approved in Japan. We present a case of NBTE that was successfully managed with anticoagulant therapy using subcutaneous unfractionated heparin. A 59-year-old woman was diagnosed with NBTE on the mitral and tricuspid valve associated with breast cancer, underwent valve replacement. Warfarin and continuous intravenous unfractionated heparin were started. However, disseminated intravascular coagulation occurred after heparin was discontinued. Continuous intravenous unfractionated heparin injection was resumed immediately, and subcutaneous unfractionated heparin was administered before discharge. Postoperative echocardiography revealed no vegetation on the prosthetic valves thereafter. Subcutaneous unfractionated heparin therapy is useful to prevent the recurrence of NBTE as the anticoagulation in outpatients.

Unified Methodology for the Primary Preclinical In Vivo Screening of New Anticoagulant Pharmaceutical Agents from Hematophagous Organisms.

The development of novel anticoagulants requires a comprehensive investigational approach that is capable of characterizing different aspects of antithrombotic activity. The necessary experiments include both in vitro assays and studies on animal models. The required in vivo approaches include the assessment of pharmacokinetic and pharmacodynamic profiles and studies of hemorrhagic and antithrombotic effects. Comparison of anticoagulants with different mechanisms of action and administration types requires unification of the experiment scheme and its adaptation to existing laboratory conditions. The rodent thrombosis models in combination with the assessment of hemostasis parameters and hematological analysis are the classic methods for conducting preclinical studies. We report an approach for the comparative study of the activity of different anticoagulants in vivo, including the investigation of pharmacodynamics and the assessment of hemorrhagic effects (tail-cut bleeding model) and pathological thrombus formation (inferior vena cava stenosis model of venous thrombosis). The reproducibility and uniformity of our set of experiments were illustrated on unfractionated heparin and dabigatran etexilate (the most common pharmaceuticals in antithrombic therapy) as comparator drugs and an experimental drug variegin from the tick Amblyomma variegatum. Variegin is notorious since it is a potential analogue of bivalirudin (Angiomax, Novartis AG, Basel, Switzerland), which is now being actively introduced into antithrombotic therapy.

Long-Term Outcomes of a Japanese Prospective Multicenter Registry Using a Heparin-Bonded Expanded Polytetrafluoroethylene Graft for Above-the-Knee Femoropopliteal Bypasses.

BACKGROUND: Despite the widespread use of PROPATEN®, a bioactive heparin-bonded expanded polytetrafluoroethylene graft, in bypass surgery, there are only a few reports of long-term results. We evaluated the long-term results of PROPATEN®use for above-knee femoropopliteal bypass (AKFPB).Methods and Results: After PROPATEN®-based AKFPB, patients were prospectively registered at 20 Japanese institutions between July 2014 and October 2017 to evaluate long-term results. During the median follow-up of 76 months (interquartile range 36-88 months) for 120 limbs (in 113 patients; mean [±SD] age 72.7±8.1 years; 66.7% male; ankle-brachial index [ABI] 0.45±0.27; lesion length 26.2±5.7 cm; chronic limb-threatening ischemia in 45 limbs), there were 8 major amputations; however, clinical improvement was sustained (mean [±SD] ABI 0.87±0.23) and the Rutherford classification grade improved in 105 (87.5%) limbs at the latest follow-up. At 8 years, the primary patency, freedom from target-lesion revascularization, secondary patency, survival, and amputation-free survival, as estimated by the Kaplan-Meier method, were 66.3±4.8%, 71.5±4.4%, 86.5±3.4%, 53.1±5.0%, and 47.4±5.3%, respectively. CONCLUSIONS: This multicenter prospective registry-based analysis showed sustained excellent clinical improvement and secondary patency for up to 8 years following PROPATEN®-based AKFPB. PROPATEN®constitutes a durable and good revascularization option for complex superficial femoral artery lesions, especially when endovascular treatment is inappropriate or an adequate venous conduit is unavailable.

Intestinal obstruction as a result of intra-abdominal hematoma: a complication of low molecular weight heparin in pediatric patients. / Obstrucción intestinal por hematoma intraabdominal: una complicación de la heparina de bajo peso molecular en el paciente pediátrico.

INTRODUCTION: Hematomas are a rare cause of intestinal obstruction. Subcutaneous heparin can bring about direct punctures on small bowel loops, potentially leading to traumatic hematoma and intestinal obstruction. CASE REPORTS: We present three cases of pediatric patients with clinical signs of intestinal obstruction treated with subcutaneous heparin. Two cases had increased acute-phase reactants and radiological signs of intestinal suffering, so surgical treatment was decided upon, with intramural hematoma emerging as an intraoperative finding. The third case was conservatively managed with anticoagulant discontinuation and gut rest, since the patient had an adequate general condition and no findings compatible with ischemia or necrosis were noted in the complementary tests. DISCUSSION: The administration of subcutaneous heparin may cause intestinal wall hematomas due to its anticoagulating effect and to the risk of inadvertent punctures on small bowel loops.

INTRODUCCION: Los hematomas son una causa poco frecuente de obstrucción intestinal. La heparina subcutánea tiene riesgo de producir la punción directa de un asa intestinal, provocando un hematoma traumático que genere una obstrucción intestinal. CASOS CLINICOS: Se describen tres casos de pacientes pediátricos con clínica de obstrucción intestinal en tratamiento con heparina subcutánea. Dos casos presentaron elevación de reactantes de fase aguda y signos radiológicos de sufrimiento intestinal por lo que se optó por tratamiento quirúrgico, con el hallazgo intraoperatorio de hematoma intramural. El tercer caso fue manejado de manera conservadora con supresión de la anticoagulación y reposo intestinal, dado el adecuado estado general y ausencia de hallazgos compatibles con isquemia o necrosis en las pruebas complementarias. COMENTARIOS: La administración de heparina subcutánea puede provocar la aparición de hematomas de pared intestinal, tanto por su efecto anticoagulante, como por el riesgo de punción inadvertida de un asa intestinal.

Ion Mobility Mass Spectrometry-based Disaccharide Analysis of Glycosaminoglycans.

Glycosaminoglycans (GAGs) are linear and acidic polysaccharides. They are ubiquitous molecules, which are involved in a wide range of biological processes. Despite being structurally simple at first glance, with a repeating backbone of alternating hexuronic acid and hexosamine dimers, GAGs display a highly complex structure, which predominantly results from their heterogeneous sulfation patterns. The commonly applied method for compositional analysis of all GAGs is "disaccharide analysis." In this process, GAGs are enzymatically depolymerized into disaccharides, derivatized with a fluorescent label, and then analysed through liquid chromatography. The limiting factor in the high throughput analysis of GAG disaccharides is the time-consuming liquid chromatography. To address this limitation, we here utilized trapped ion mobility-mass spectrometry (TIM-MS) for the separation of isomeric GAG disaccharides, which reduces the measurement time from hours to a few minutes. A full set of disaccharides comprises twelve structures, with eight possessing isomers. Most disaccharides cannot be differentiated by TIM-MS in underivatized form. Therefore, we developed chemical modifications to reduce sample complexity and enhance differentiability. Quantification is performed using stable isotope labelled standards, which are easily available due to the nature of the performed modifications.

Evaluating the Use of Unfractionated Heparin with Intra-Aortic Balloon Counterpulsation.

BACKGROUND: Evidence supporting anticoagulation with unfractionated heparin (UFH) in patients with an intra-aortic balloon pump (IABP) to prevent limb ischaemia remains limited, while bleeding risks remain high. Monitoring heparin in this setting with anti-factor Xa (anti-Xa) is not previously described. OBJECTIVES: The study objective is to describe the incidence of thromboembolic and bleeding events with the use of UFH in patients with an IABP utilising monitoring with both anti-Xa and activated partial thromboplastin time (aPTT). METHODS: This is a retrospective study of adults who received an IABP and UFH for ≥24 hours. Electronic medical records were reviewed for pertinent data. The primary outcome was the incidence of limb ischaemia during IABP. Secondary outcomes included myocardial infarction, thrombus on IABP, or stroke. Exploratory outcomes included any venous thromboembolism and bleeding events. RESULTS: Of 159 patients, 88% received an IABP for cardiogenic shock and median duration of IABP support was 118 hours (interquartile range, 67-196). Limb ischaemia occurred in four of 159 patients (2.5%). Strokes occurred in 3.8% of the cohort, and bleeding events occurred in 33%. Despite anticoagulation use in all patients, 11% experienced a venous thromboembolism, with most identified upon asymptomatic screening with concern for heparin-induced thrombocytopenia. We found no differences in outcomes that occurred with a hybrid anti-Xa and aPTT versus aPTT monitoring alone. CONCLUSIONS: We observed a high rate of thrombotic and bleeding complications with the use of UFH in patients with an IABP. Use of anti-Xa versus aPTT for monitoring was not associated with complications. These data suggest safer anticoagulation strategies are needed in this setting.

Bivalirudin versus heparin in ST and non-ST-segment elevation myocardial infarction-Outcomes at two years.

BACKGROUND: The registry-based randomized VALIDATE-SWEDEHEART trial (NCT02311231) compared bivalirudin vs. heparin in patients undergoing percutaneous coronary intervention (PCI) for myocardial infarction (MI). It showed no difference in the composite primary endpoint of death, MI, or major bleeding at 180 days. Here, we report outcomes at two years. METHODS: Analysis of primary and secondary endpoints at two years of follow-up was prespecified in the study protocol. We report the study results for the extended follow-up time here. RESULTS: In total, 6006 patients were enrolled, 3005 with ST-segment elevation MI (STEMI) and 3001 with Non-STEMI (NSTEMI), representing 70 % of all eligible patients with these diagnoses during the study. The primary endpoint occurred in 14.0 % (421 of 3004) in the bivalirudin group compared with 14.3 % (429 of 3002) in the heparin group (hazard ratio [HR] 0.97; 95 % confidence interval [CI], 0.85-1.11; P = 0.70) at one year and in 16.7 % (503 of 3004) compared with 17.1 % (514 of 3002), (HR 0.97; 95 % CI, 0.96-1.10; P = 0.66) at two years. The results were consistent in patients with STEMI and NSTEMI and across major subgroups. CONCLUSIONS: Until the two-year follow-up, there were no differences in endpoints between patients with MI undergoing PCI and allocated to bivalirudin compared with those allocated to heparin. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02311231.

Clinical guidelines for prevention and treatment of CAT in Japan and other countries.

Cancer-associated thrombosis (CAT) is an important prognostic factor for an increasing number of cancer patients. Understanding of CAT among cancer care providers has grown in recent years, and guidelines for the prevention and treatment of CAT have been published in Japan and around the world. In this article, we introduce these major guidelines and discuss differences we identified between the Japanese guidelines and those of other countries, with a focus on problems and issues. Insurance coverage of low-molecular-weight heparin and indications for primary prevention with direct oral anticoagulants in particular require urgent consideration.

The Standard-Dose Heparin-Warfarin Remedy Partially Resolves Thrombi in the Right Superior Pulmonary Vein and Left Atrium and Ameliorates Type 2 Diabetes Mellitus.

Pulmonary vein thrombosis is common and underdiagnosed. Previously, we reported several cases of pulmonary vein thrombi (PVTs) using cardiac computed tomography (CT) and transesophageal echocardiography (TEE). We reported that warfarin and direct oral anticoagulants (DOACs) partially resolved PVTs; however, it is difficult to resolve all PVTs completely. Therefore, we evaluated the effects of standard-dose heparin-warfarin remedy on PVTs and left atrium (LA) thrombi using TEE and cardiac CT. A 64-year-old male with type 2 diabetes mellitus (T2DM) and hypertension was assessed for thrombi in the LA and pulmonary veins using TEE and 80-slice multidetector computed tomography (80-MDCT). After one month of standard-dose heparin-warfarin remedy, the patient's right superior pulmonary vein (RSPV) thrombi and expanded LA thrombi from the RSPV thrombi had partially resolved. The RSPV thrombi and the expanded LA thrombi from the RSPV thrombi were detected using cardiac CT and TEE; however, they were depicted as black areas on TEE. They periodically moved inward with the patient's heartbeats. Additionally, the standard-dose heparin-warfarin remedy ameliorated the patient's T2DM, and the remedy effect could be maintained for five months to some extent by administering a standard dose of warfarin. The standard-dose heparin-warfarin remedy can ameliorate not only T2DM but also diabetic complications such as diabetic nephropathy and gestational diabetes mellitus.

d-type peptides based fluorescent probes for "turn on" sensing of heparin.

Developing "turn on" fluorescent probes was desirable for the detection of the effective anticoagulant agent heparin in clinical applications. Through combining the aggregation induced emission (AIE) fluorogen tetraphenylethene (TPE) and heparin specific binding peptide AG73, the promising "turn on" fluorescent probe TPE-1 has been developed. Nevertheless, although TPE-1 could achieve the sensitive and selective detection of heparin, the low proteolytic stability and undesirable poor solubility may limit its widespread applications. In this study, seven TPE-1 derived fluorescent probes were rationally designed, efficiently synthesized and evaluated. The stability and water solubility were systematically estimated. Especially, to achieve real-time monitoring of proteolytic stability, the novel Abz/Dnp-based "turn on" probes that employ the internally quenched fluorescent (IQF) mechanism were designed and synthesized. Moreover, the detection ability of synthetic fluorescent probes for heparin were systematically evaluated. Importantly, the performance of d-type peptide fluorescent probe XH-6 indicated that d-type amino acid substitutions could significantly improve the proteolytic stability without compromising its ability of heparin sensing, and attaching solubilizing tag 2-(2-aminoethoxy) ethoxy) acid (AEEA) could greatly enhance the solubility. Collectively, this study not only established practical strategies to improve both the water solubility and proteolytic stability of "turn on" fluorescent probes for heparin sensing, but also provided valuable references for the subsequent development of enzymatic hydrolysis-resistant d-type peptides based fluorescent probes.

A systematic review and meta-analysis of the effectiveness of primary thromboprophylaxis in acute lymphoblastic leukemia during early-phase therapy including asparaginase or its prolonged form.

Asparaginase is essential in the initial management of acute lymphoblastic leukemia (ALL) but frequently leads to venous thromboembolism (VTE). Using anticoagulants for primary VTE prevention has been studied with no consensus. We conducted a systematic literature search in PubMed, Scopus, and Web of science and performed random-effect meta-analysis using Mantel-Haenszel method in RevMan 5.4 to analyze primary pharmacological thromboprophylaxis during asparaginase treatment in early-phase (induction, consolidation, or intensification phase) therapy in patients with ALL with all ages and followed with subgroup analysis by age. Meta-analysis of 13 articles describing the effect of antithrombin supplementation in 1375 patients showed that antithrombin prophylaxis decreases the risk of VTE by 43% (RR, 0.57; 95% CI, 0.38 - 0.83; p=0.004), with mild heterogeneity (I2=35%, p=0.10) and moderate certainty by GRADE. 8 articles included for meta-analysis of low-molecular weight heparin (LMWH) treatment in 612 patients showed that it decreased the risk of VTE by nearly 40% (RR, 0.61; 95% CI, 0.45 - 0.81; p=0.00081), with minimal heterogeneity (I2=14%, p=0.31) but low certainty. Subgroup analysis showed that only prophylaxis with antithrombin supplementation significantly decreased the VTE rate in adult patients with moderate certainty. In pediatric patients, one nonrandomized prospective study showed that LMWH combined with antithrombin has a better thromboprophylaxis effect than antithrombin alone. In the PREVAPIX-ALL trial, prophylaxis with direct factor Xa inhibitor Apixaban did not benefit children younger than 18 years except for cases of obesity. We concluded that thromboprophylaxis with antithrombin is effective in ALL patients older than 18 years during the early phase of therapy, and LMWH combined with antithrombin supplementation might be effective for pediatric patients with ALL. Apixaban is effective in pediatric ALL patients with obesity and needs further study in other high-risk patients.

Spurious Hyperphosphatemia in Two Children With End-Stage Renal Disease: A Case Report.

Spurious hyperphosphatemia, also known as pseudo-hyperphosphatemia, refers to artifactually elevated serum phosphate values that do not correspond to their actual systemic levels. Vascular access poses a significant challenge for individuals undergoing hemodialysis (HD) due to chronic kidney disease, primarily attributed to the elevated incidence of complications, such as infections or thrombosis associated with catheter use. To mitigate clotting risk during the inter-dialysis intervals, in recent years, a strategy involving the application of concentrated heparin (recombinant tissue plasminogen activator (rt-PA) e.g. alteplase) has been used. These infusions have a very high content of phosphorus, and if it is not removed sufficiently before collecting blood samples through the central venous catheter, it can cause erroneously high phosphate levels. Here we report two cases of pseudo-hyperphosphatemia caused by contaminated blood samples obtained from an HD catheter from the pediatric nephrology department. Absurd values found in routine samples led us to investigate the reason for these results. Further investigations carried out by the laboratory biochemistry department showed that all the analytical checks and proficiency testing performance were within acceptable limits. We hypothesized that there was a pre-analytical error such as possible contamination with the high phosphate content of heparin and alteplase solution in the catheter, contributing to the increased phosphate levels in these samples.

Antithrombin supplementation attenuates heparin resistance in plasma spiked with Gla-domainless factor Xa S195A in vitro.

BACKGROUND: Andexanet alfa is a Gla-domainless mutant (S195A) factor Xa (GDXa) approved for acute reversal of oral factor Xa inhibitors. Cardiac surgery patients exposed to andexanet before cardiopulmonary bypass often exhibit severe heparin resistance. There is a paucity of data on the effectiveness and optimal dosage of antithrombin use in this setting. The objective of this study was to evaluate the in vitro effect of increased heparin with antithrombin levels on attenuating heparin resistance induced by GDXa. METHODS: Heparinised normal pooled plasma and cardiopulmonary bypass plasma were spiked with GDXa 4 µM. Tissue factor-activated thrombin generation was used to assess heparin reversal effects of GDXa and restoration of anticoagulation with additional heparin with and without antithrombin. Serum thrombin-antithrombin complex, antithrombin activity, and tissue factor pathway inhibitor were also measured in tissue factor-activated, recalcified cardiopulmonary bypass plasma spiked with GDXa. RESULTS: In normal pooled plasma, GDXa-induced heparin reversal was mitigated by maintaining a high heparin concentration (12 U ml-1) and supplementing antithrombin (1.5-4.5 µM) based on peak and velocity of thrombin generation. Heparin reversal by GDXa was also demonstrated in cardiopulmonary bypass plasma, but supplementing both heparin (8 U ml-1) and antithrombin (3 µM) attenuated GDXa-induced changes in peak and velocity of thrombin generation by 72.5% and 72.2%, respectively. High heparin and antithrombin levels attenuated thrombin-antithrombin complex formation in tissue factor-activated, GDXa-spiked cardiopulmonary bypass plasma by 85.7%, but tissue factor pathway inhibitor remained depleted compared with control cardiopulmonary bypass plasma. CONCLUSIONS: Simultaneous supplementation of heparin and antithrombin mitigate GDXa-induced heparin resistance by compensating for the loss of tissue factor pathway inhibitor.

High-Dose Immunoglobulin Therapy for Multiple Thromboembolism in Persisting Heparin-Induced Thrombocytopenia.

This report presents a case of an 81-year-old male with acute respiratory distress syndrome secondary to aspiration pneumonia who developed heparin-induced thrombocytopenia (HIT). His platelet count remained persistently low despite discontinuing unfractionated heparin and initiating intravenous argatroban. Multiple thromboembolisms, including a new aortic mural thrombus in the descending aorta, were observed on contrast-enhanced computed tomography (CT), resulting in a diagnosis of autoimmune HIT (aHIT). Subsequent high-dose intravenous immunoglobulin (IVIG) therapy substantially improved the platelet count and resolved thromboembolisms. This case is notable owing to the improvement of aHIT complicated by multiple thromboembolisms, including an aortic mural thrombus, following high-dose IVIG therapy. In recent years, a growing number of reports have documented the effectiveness of high-dose IVIG therapy for aHIT. However, reports on whether high-dose IVIG therapy could improve an aortic mural thrombus complicating aHIT are lacking. The successful use of high-dose IVIG therapy in the current case highlights its potential efficacy in treating aHIT complicated by multiple thromboembolisms. Further studies are required to clarify the role of IVIG in the management of aHIT with thromboembolism.