Risk Of Venous Thrombosis Research Articles

The Role of Platelet Activation in the Development and Metastasis of Solid Tumors

The blood coagulation system is actively involved in the development of cancer. It is known that many solid tumors express tissue factor, a “trigger” of the cascade of plasma coagulation reactions, which leads to an increased risk of cancer-associated thrombosis and venous thrombosis in cancer patients. It has also long been known that platelets - small cellular fragments that are the basis of blood clots - play a critical role in metastasis by binding to the tumor cell after it enters the blood vessel, “shielding” it from the immune system and promoting the adhesion and extravasation of the tumor cell into tissues and the formation metastasis. In addition, platelets, being mobile “storehouses” of growth factors, are actively attracted and, in some cases, consumed by the tumor, which contributes to its development and vascularization. Platelet attraction occurs both through activation of the blood coagulation system in the tumor area and through exposure of the adhesive surface by the tumor. Activated in the tumor vicinity, platelets attract and induce neutrophil activation and the formation of neutrophil extracellular traps (NETs), thereby modulating the tumor microenvironment. When activated, platelets are known to secrete a variety of growth factors that promote both tumor development and vascularization. In addition to direct interaction, platelets and tumor cells exchange mRNA, micro-RNA and other regulatory molecules through microvesicles, while platelets are containers for the spread of tumor genetic material (circulating nucleic acids) throughout the body. In this review, we consider the molecular mechanisms of platelet participation in the development and metastasis of solid tumors, and also discuss possible options for pharmacological interruption of this interaction.

Aspirin therapy is associated with a lower risk of pregnancy loss in both JAK2- and CALR-mutated essential thrombocythemia-A Mayo Clinic study of 200 pregnancies.

Two-hundred pregnancies involving 100 women with essential thrombocythemia (ET) were accessed from Mayo Clinic databases (1990-2023). Median platelet count displayed a decline during pregnancy, nadiring at 48% of baseline, in the third trimester: 704-369 × 109/L. Live birth rate was 72%. Of 53 (27%) unintentional pregnancy losses, 48 (24%) occurred in the first trimester. Other fetal complications included preterm birth 3%, intrauterine growth retardation 3%, and stillbirth 1%. Maternal complications included major hemorrhage (7%), preeclampsia (6%), thrombosis (1%), and placental abruption (0.5%). Antepartum management included no specific therapy in 52 (26%), aspirin alone in 112 (56%), aspirin combined with cytoreductive drugs or systemic anticoagulants in 23 (12%), and other permutations in the remaining. Postpartum systemic anticoagulation was documented in 29 (15%) pregnancies. Unintentional first-trimester loss was predicted by prior fetal loss (43% vs. 18%; p < .01), diabetes mellitus (DM; 67% vs. 23%; p = .02), and absence of aspirin therapy (45% vs. 14%; p < .01); the salutary effect of aspirin therapy was independent of the other two risk factors and apparent in both high (presence of ≥1 risk factor; 33% vs. 61%; p = .07) and low (absence of both risk factors; 10% vs. 34%; p < .01) risk scenarios. The benefit of aspirin therapy, in preventing first-trimester loss, was significant in both JAK2-mutated (18% vs. 50%; p < .01) and CALR-mutated (8% vs. 43%; p < .01) cases. Aspirin use was also associated with a lower risk of venous thrombosis (0% vs. 3%; p = .03). By contrast, the use of systemic anticoagulation, antepartum or postpartum, did not influence fetal or maternal complication rates. CALR mutation and DM predicted maternal hemorrhage (13% vs. 4%; p = .05) and preeclampsia (33% vs. 5%; p = .03), respectively. The current study demonstrates the protective role of aspirin in preventing first-trimester loss in ET, independent of driver mutation status or other risk factors.

C-reactive protein is a predictor for lower-extremity deep venous thrombosis in patients with primary intracerebral hemorrhage

ObjectiveOur study aimed to determine whether there exists an association between low-grade systemic inflammation, as measured by serum C-reactive protein (CRP), and the risk of lower-extremity deep venous thrombosis (LEDVT) in patients with primary intracerebral hemorrhage (ICH).MethodsThis observational study was retrospectively conducted on patients with primary ICH who were presented to two tertiary medical centers between January 2021 and August 2022. The primary outcome was detecting LEDVT occurrence within 14 days from the onset of the acute ICH episode. Weighted logistic regression and restricted cubic spline models were employed to estimate the association between CRP and LEDVT following 1:1 propensity score matching (PSM).ResultsOf the 538 patients with primary ICH who met the inclusion criteria, 76 (14.13%) experienced LEDVT. Based on the cut-off levels of CRP measured upon admission from the receiver operating characteristic (ROC) curve, patients with primary ICH were categorized into two groups: (i) CRP < 1.59 mg/L and (ii) CRP ≥ 1.59 mg/L. After 1:1 PSM, the LEDVT events occurred in 24.6% of patients with CRP ≥ 1.59 mg/L and 4.1% of patients with CRP < 1.59 mg/L (P < 0.001). ROC curve revealed the area under the ROC curve of 0.717 [95% confidence interval (CI) 0.669–0.761, P < 0.001] for CRP to predict LEDVT with a sensitivity of 85.71% and specificity of 56.29%. After adjusting for all confounding variables, the occurrence of LEDVT in ICH patients with higher CRP levels (≥ 1.59 mg/L) was 10.8 times higher compared to those with lower CRP levels (95% CI 4.5–25.8, P < 0.001). A nonlinear association was observed between CRP and an increased risk of LEDVT in the fully adjusted model (P for overall < 0.001, P for nonlinear = 0.001). The subgroup results indicated a consistent positive link between CRP and LEDVT events following primary ICH.ConclusionsHigher initial CRP levels (CRP as a dichotomized variable) in patients with primary ICH are significantly associated with an increased risk of LEDVT and may help identify high-risk patients with LEDVT. Clinicians should be vigilant to enable early and effective intervention in patients at high risk of LEDVT.

Association between socioeconomic and psychosocial factors with use of interventional and surgical treatments and outcomes in patients with myocardial infarction – Inpatient data of the largest European health care system

BackgroundMyocardial infarction (MI) is an important driver of both morbidity and mortality on a global scale. Elucidating social inequalities may help to identify vulnerable groups as well as treatment imbalances and guide efforts to improve care for MI. MethodsAll hospitalized patient-cases with confirmed MI 2005-2020 in Germany were included in the study and stratified for socioeconomic or psychosocial factors (SPF) and the impact of SPF on treatment usage and adverse in-hospital events was analyzed. ResultsOverall, 4,409,597 hospitalizations of MI patients were included; of these, 17,297 (0.4 %) were coded with SPF. These patients were more often of female sex (49.4 % vs. 36.9 %, P<0.001), older (median 77.0 [IQR: 65.0–84.0] vs. 73.0 [62.0–81.0] years, P<0.001) and revealed an aggravated cardiovascular profile. Although SPF were independently associated with increased usage of cardiac catheterization (OR 1.174 [95 %CI 1.136-1.212]) and percutaneous coronary intervention (OR 1.167 [95 %CI 1.130-1.205]), they were accompanied by higher risk for a prolonged length of in-hospital stay >7 days (OR 1.236 [95 %CI 1.198-1.276]) and >10 days (OR 1.296 [95 %CI 1.254-1.339]). While SPF were associated with increased risk for deep venous thrombosis and/or thrombophlebitis (OR 1.634 [95 %CI 1.427-1.870]), pulmonary embolism (OR 1.337 [95 %CI 1.149-1.555]), and acute renal failure (OR 1.170 [95 %CI 1.105-1.240), these SPF were inversely associated with in-hospital case-fatality (OR 0.461 [95 %CI 0.433-0.490]). ConclusionsThis study demonstrates that SPF in hospitalized MI patients have significant impacts on treatments and outcomes. Fortunately, our data did not revealed an underuse of interventional treatments in MI patients with SPF.

Protease activated receptor-4: ready to be part of the antithrombosis spectrum.

Cardiovascular disease is a major cause of death worldwide. Platelets play a key role in this pathological process. The serine protease thrombin is a critical regulator of platelet reactivity through protease activated receptors-1 (PAR1) and PAR4. Since targeting PAR4 comes with a low chance for bleeding, strategies blocking PAR4 function have great antithrombotic potential. Here, we reviewed the literature on platelet PAR4 with a particular focus on its role in thromboinflammation. Functional PAR4 variants are associated with reduced venous thrombosis risk (rs2227376) and increased risk for ischemic stroke (rs773902). Recent advances have allowed for the creation of humanized mouse lines in which human PAR4 is express instead of murine PAR4. This has led to a better understanding of the discrepancies between human and murine PAR4. It also made it possible to introduce single nucleotide polymorphisms (SNPs) in mice allowing to directly test the in vivo functional effects of a specific SNP and to develop in vivo models to study mechanistic and pharmacologic alterations induced by a SNP. PAR4 plays an important role in cardiovascular diseases including stroke, myocardial infarction and atherosclerosis. Targeting PAR4 hold great potential as a safe antithrombotic strategy.

Prophylactic Anticoagulation Reduces the Risk of Kidney Graft Venous Thrombosis in Recipients From Uncontrolled Donation After Circulatory Death Donors With High Renal Resistive Index.

Uncontrolled donation after circulatory death (uDCD) increases organ availability for kidney transplantation (KT) at the expense of a higher risk of primary graft nonfunction (PNF). At least half of the cases of PNF are secondary to graft venous thrombosis. The potential benefit from prophylactic anticoagulation in this scenario remains unclear. In this single-center retrospective study we compared 2 consecutive cohorts of KT from uDCD with increased (≥0.8) renal resistive index (RRI) in the Doppler ultrasound examination performed within the first 24-72 h after transplantation: 36 patients did not receive anticoagulation ("nonanticoagulation group") and 71 patients underwent prophylactic anticoagulation until normalization of RRI in follow-up Doppler examinations ("anticoagulation group"). Anticoagulation was initiated at a median of 2 d (interquartile range, 2-3) after transplantation and maintained for a median of 12 d (interquartile range, 7-18). In 4 patients (5.6%), anticoagulation had to be prematurely stopped because of the development of a hemorrhagic complication. In comparison with the nonanticoagulation group, recipients in the anticoagulation group had a lower 2-wk cumulative incidence of graft venous thrombosis (19.4% versus 0.0%; P < 0.001) and PNF (19.4% versus 2.8%; P = 0.006). The competing risk analysis with nonthrombotic causes of PNF as the competitive event confirmed the higher risk of graft thrombosis in the nonanticoagulation group (P = 0.0001). The anticoagulation group had a higher incidence of macroscopic hematuria (21.1% versus 5.6%; P = 0.049) and blood transfusion requirements (39.4% versus 19.4%; P = 0.050) compared with the nonanticoagulation group. No graft losses or deaths were attributable to complications potentially associated with anticoagulation. Early initiation of prophylactic anticoagulation in selected KT recipients from uDCD with an early Doppler ultrasound RRI of ≥0.8 within the first 24-72 h may reduce the incidence of graft venous thrombosis as a cause of PNF.

Comparison of an Unlabeled Probe High-Resolution Melting Analysis Assay (HRMA) for Factor V Leiden 1691 G/A Mutation to a Fluorogenic 5' Nuclease PCR Hydrolysis Assay.

The clinically significant Factor V Leiden (FVL) point mutation (1691 G/A) causes replacement of Arg with Gln (glutamine), preventing activated protein C from inactivating Factor V leading to a lengthened clotting process. Individuals with the Factor V Leiden mutations have an increased risk for venous thrombosis. The aim of this study is to compare an unlabeled probe high-resolution melting analysis (HRMA) assay for Factor V Leiden mutation to a TaqMan hydrolysis assay (fluorogenic 5' nuclease PCR hydrolysis assay). HRMA is a post-PCR, homogenous, closed-tube system for the detection of sequence variants. Post-PCR, the amplicons are heated gradually until the melting temperature is reached and the fluorescent dye unbinds from the amplicon and exhibits low fluorescence. A melt-curve analysis is generated that is characteristic of a particular sequence variant. Therefore, HRMA allows for comparison of one base changes in genetic sequences based on their differences in melting rate. Blood samples were collected in EDTA tubes and DNA extracted using the Roche MagNaPure. Reactions of both HRMA and TaqMan were carried out on 3 controls (1691 G/G, 1691 G/A, and 1691 G/G and G/A) and 20 samples. The genotypes for 3 reference controls purchased from Coriell (F5 1691 G/G, FVL 1691 G/A, and Heterozygote 1691 G/G and G/A) were confirmed by both the HRMA and TaqMan FVL assays. All 20 samples were confirmed to be F5 1691 G/G by both HRMA and TaqMan assays. Comparing the results of the unlabeled probe HRMA FVL assay with a real-time TaqMan probe end point genotyping assay resulted in 100% sensitivity and 100% specificity for both assays.

Prone Position and the Risk of Venous Thrombosis in COVID-19 Patients with Respiratory Failure.

Prone Position and the Risk of Venous Thrombosis in COVID-19 Patients with Respiratory Failure.

Risk of deep venous thrombosis associated with peripherally inserted central catheter: A retrospective cohort study of 11.588 catheters in Brazil.

Deep Venous Thrombosis (DVT) due to Peripherally Inserted Central Catheter (PICC) is one of the most threatening complications after device insertion. To assess the rate of PICC-associated DVT and analyze the risk factors associated with this event in cancer and critically ill patients. We conducted a descriptive, retrospective cohort study with 11,588 PICCs from December 2014 to December 2019. Patients ≥ 18 years receiving a PICC were included. Pre-and post-puncture variables were collected and a logistic regression was used to identify the independent factors associated with the risk of DVT. The DVT prevalence was 1.8% (n = 213). The median length of PICC use was 15.3 days. The median age was 75 years (18; 107) and 52% were men, 53.5% were critically ill and 29.1% oncological patients. The most common indications for PICC's were intravenous antibiotics (79.1%). Notably, 91.5% of PICC showed a catheter-to-vein ratio of no more than 33%. The tip location method with intracavitary electrocardiogram was used in 43%. Most catheters (67.9%) were electively removed at the end of intravenous therapy. After adjusting for cancer profile ou chemotherapy, regression anaysis revealed that age (OR 1.011; 95% CI 1.002-1.020), previous DVT (OR 1.96; 95% CI 1.12-3.44) and obstruction of the device (OR 1.60; 95% CI 1.05-2.42) were independent factors associated with PICC-associated DVT, whereas the use of an anticoagulant regimen was a protective variable (OR 0.73; 95% CI 0.54-0.99). PICC is a safe and suitable intravenous device for medium and long-term therapy, with low rates of DVT even in a cohort of critically ill and cancer patients.

Successful management of postpartum venous thrombosis following splenectomy for traumatic splenic rupture: a case report.

Traumatic splenic rupture is rare in pregnant women; and multiple venous thromboses of the portal vein system, inferior vena cava and ovarian vein after caesarean section and splenectomy for splenic rupture has not been previously reported. This case report describes a case of multiple venous thromboses after caesarean section and splenectomy for traumatic splenic rupture in late pregnancy. A 34-year-old G3P1 female presented with abdominal trauma at 33+1 weeks of gestation. After diagnosis of splenic rupture, she underwent an emergency caesarean section and splenectomy. Multiple venous thromboses developed during the recovery period. The patient eventually recovered after anticoagulation therapy with low-molecular-weight heparin and warfarin. These findings suggest that in patients that have had a caesarean section and a splenectomy, which together might further increase the risk of venous thrombosis, any abdominal pain should be thoroughly investigated and thrombosis should be ruled out, including the possibility of multiple venous thromboses. Anticoagulant therapy could be extended after the surgery.

Assessment of the risk of venous thrombosis and embolism in operated patients with acute surgical pathology of abdominal organs against the background of COVID–19

Assessment of the risk of venous thrombosis and embolism in operated patients with acute surgical pathology of abdominal organs against the background of COVID–19

Topical Application of Oral Contraceptive Pills and the Risk of Cerebral Venous Thrombosis: A Novel Case Study in a Male Patient (P7-5.025)

Topical Application of Oral Contraceptive Pills and the Risk of Cerebral Venous Thrombosis: A Novel Case Study in a Male Patient (P7-5.025)

Effectiveness of rivaroxaban in preventing cerebral venous thromboembolism: a systematic review and meta-analysis.

Cerebral venous thromboembolism (CVT) poses a significant risk of venous infarction and haemorrhage, which can lead to neurological deficits and, in severe cases, even death. The optimal treatment regimen for patients with CVT remains unclear. MEDLINE, Embase, Google Scholar, Web of Science (WoS), and Cochrane Central databases were searched for randomized controlled trials (RCTs) and observational studies assessing the efficacy and safety of rivaroxaban in patients with CVT. All-site venous thromboembolism (VTE), risk of clinically relevant non-major bleeding, incidence of partial recanalization, complete recanalization and major haemorrhage were among outcomes of interest. Mantel-Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95% CIs. The analysis included 1 RCT and 3 observational studies containing 211 patients. Compared to vitamin K antagonists (VKAs), rivaroxaban did not significantly decrease the all-site VTE [RR 0.31 (95% CI 0.01, 8.43); P=0.49, I2=0%]. Compared with VKAs, patients on rivaroxaban did not show a significantly reduced risk of recurrent cerebral venous thrombosis. In terms of incidence of partial recanalization, there was no discernible difference between rivaroxaban and VKAs [RR 0.90 (95% CI 0.66, 1.22); P=0.49, I2=0%]. There was no discernible difference in incidence of complete recanalization [RR 0.98 (95% CI 0.32, 3.03); P=0.97, I2=28%] and incidence of major haemorrhage [RR 0.19 (95% CI 0.01, 4.54); P=0.30]. Rivaroxaban was found to have similar efficacy to VKAs. Due to its lower risk of severe bleeding and no need for INR monitoring, rivaroxaban may be a preferable treatment option for CVT.

327 Sustained Improvement in Compliance With Use of Sequential Compression Devices in a Neurosurgery Patient Population of a Safety-Net Hospital

INTRODUCTION: Sequential Compression Devices (SCDs) are utilized in perioperative patients given increased risks of deep venous thrombosis from mobility reductions and post-operative inflammatory responses. Additionally, mechanical prophylaxis is crucial in patients where chemical prophylaxis is contraindicated. Previous work has found SCD compliance far less than expected. METHODS: Across a 9-month period (August-April), we tracked which neurosurgical patients in stepdown units had SCDs on and properly functioning. When not on or properly functioning, we documented the missing element. Compliance was calculated daily as the percentage of patients who were SCD compliant out of all patients with SCD orders, then averaged over the month, for each month. Most common barriers to compliance were identified. Together with nursing management, we designed and implemented a best practice alert to facilitate nursing education and supply chain management, at month 3. The impact was tracked over the next six months, with a 4-months break from November-February. RESULTS: Compliance averaged 19.7% (n = 95) during August, and 38.4% (n = 131) in September. After implementation of the best practice nursing alert and supply chain upgrades, compliance was 48.8% (n = 150) in October, 41.2% (n = 104) in March, and 45.9% (n = 76) in April. Residual barriers to compliance included patient behavior and equipment issues. Compliance was significantly increased from baseline in August to October (z = 5.042). The significant difference was sustained through March (z = 3.402) and April (z = 3.730). CONCLUSIONS: While initial improvement was attributed to a Hawthorne effect, implementation of the best practice nursing alert likely facilitated the sustained improvement in SCD compliance despite the break in surveillance. SCD compliance nonetheless remained below 50%. Further study is warranted to address the remaining barriers, such as improving patient engagement and minimizing equipment malfunction.

Association of persistent postoperative hyperglycemia with mortality after elective craniotomy.

The influence of persistent postoperative hyperglycemia after craniotomy has not yet been explored. This study aimed to investigate the hypothesis that persistent postoperative hyperglycemia is associated with mortality in patients undergoing an elective craniotomy. This study included adult patients (age ≥ 18 years) undergoing an elective craniotomy between January 2011 and March 2021 at the West China Hospital, Sichuan University. Peak daily blood glucose values measured within the first 7 days after craniotomy were collected. Persistent hyperglycemia was defined by two or more consecutive serum glucose levels of mild, moderate, or severe hyperglycemia. Normoglycemia, mild hyperglycemia, moderate hyperglycemia, and severe hyperglycemia were defined as glucose values of ≤ 6.1 mmol/L, > 6.1 and ≤ 7.8 mmol/L, > 7.8 and ≤ 10.0 mmol/L, and > 10.0 mmol/L, respectively. This study included 14,907 patients undergoing an elective craniotomy. In the multivariable analysis, both moderate (adjusted OR 3.76, 95% CI 2.68-5.27) and severe (adjusted OR 3.82, 95% CI 2.54-5.76) persistent hyperglycemia in patients were associated with higher 30-day mortality compared with normoglycemia. However, this association was not observed in patients with mild hyperglycemia (adjusted OR 1.32, 95% CI 0.93-1.88). Interestingly, this association was observed regardless of whether patients had preoperative hyperglycemia. There was no interaction between moderate or severe hyperglycemia and preexisting diabetes (p for interaction = 0.65). When postoperative peak blood glucose values within the first 7 days after craniotomy were evaluated as a continuous variable, for each 1-mmol/L increase in blood glucose, the adjusted OR of 30-day mortality was 1.17 (95% CI 1.14-1.21). Postoperative blood glucose (area under the curve [AUC] = 0.78) was superior to preoperative blood glucose (AUC = 0.65; p < 0.001) for predicting mortality. Moderate and severe persistent hyperglycemia in patients were associated with an increased risk of deep venous thrombosis (adjusted OR 3.20, 95% CI 2.31-4.42), pneumonia (adjusted OR 2.77, 95% CI 2.40-3.21), myocardial infarction (adjusted OR 4.38, 95% CI 3.41-5.61), and prolonged hospital stays (adjusted OR 1.43, 95% CI 1.29-1.59). In patients undergoing an elective craniotomy, moderate and severe persistent postoperative hyperglycemia were associated with an increased risk of mortality compared with normoglycemia, regardless of preoperative hyperglycemia.

Does Thrombosis Play a Causal Role in Lacunar Stroke and Cerebral Small Vessel Disease?

The importance of thromboembolism in the pathogenesis of lacunar stroke (LS), resulting from cerebral small vessel disease (cSVD), is debated, and although antiplatelets are widely used in secondary prevention after LS, there is limited trial evidence from well-subtyped patients to support this approach. We sought to evaluate whether altered anticoagulation plays a causal role in LS and cSVD using 2-sample Mendelian randomization. From a recent genome-wide association study (n=81 190), we used 119 genetic variants associated with venous thrombosis at genome-wide significance (P<5*10-8) and with a linkage disequilibrium r2<0.001 as instrumental variables. We also used genetic associations with stroke from the GIGASTROKE consortium (62 100 ischemic stroke cases: 10 804 cardioembolic stroke, 6399 large-artery stroke, and 6811 LS). In view of the lower specificity for LS with the CT-based phenotyping mainly used in GIGASTROKE, we also used data from patients with magnetic resonance imaging-confirmed LS (n=3199). We also investigated associations with more chronic magnetic resonance imaging features of cSVD, namely, white matter hyperintensities (n=37 355) and diffusion tensor imaging metrics (n=36 533). Mendelian randomization analyses showed that genetic predisposition to venous thrombosis was associated with an increased odds of any ischemic stroke (odds ratio [OR], 1.19 [95% CI, 1.13-1.26]), cardioembolic stroke (OR, 1.32 [95% CI, 1.21-1.45]), and large-artery stroke (OR, 1.41 [95% CI, 1.26-1.57]) but not with LS (OR, 1.07 [95% CI, 0.99-1.17]) in GIGASTROKE. Similar results were found for magnetic resonance imaging-confirmed LS (OR, 0.94 [95% CI, 0.81-1.09]). Genetically predicted risk of venous thrombosis was not associated with imaging markers of cSVD. These findings suggest that altered thrombosis plays a role in the risk of cardioembolic and large-artery stroke but is not a causal risk factor for LS or imaging markers of cSVD. This raises the possibility that antithrombotic medication may be less effective in cSVD and underscores the necessity for further trials in well-subtyped cohorts with LS to evaluate the efficacy of different antithrombotic regimens in LS.

Establishment of a hybrid model of atherosclerosis and acute colitis in ApoE-/- mice.

Inflammatory bowel disease (IBD) and atherosclerosis (AS) are both common chronic inflammatory diseases with similar pathophysiological mechanisms. Some studies have shown that IBD patients are at increased risk for early atherosclerosis, myocardial infarction and venous thrombosis. Here we set up a hybrid mouse model associated with atherosclerosis and acute colitis in order to investigate the interplay of the two diseases. We fed ApoE-/- mice with high fat diet to establish atherosclerosis model, and used animal ultrasound machine to detect the artery of mice noninvasively. Then a new hybrid model of atherosclerosis and acute colitis was prepared by drinking water for 7 days. At the end of the experiment, the hybrid model mice showed typically pathological and intuitionistic changes of atherosclerosis and acute colitis. We found the shortened colon length, high histopathological scores of the colon with mucosal erosion and necrosis, hyperlipidemia, a plaque-covered mouse aorta and plaque with foam cells and lipid deposition in the hybrid model group, which proved that the hybrid model was successfully established. At the same time, ultrasonic detection showed that the end-diastolic blood flow velocity and the relative dilation value were decreased, while systolic time / diastolic time, the wall thickness, systolic diameters as well as diastolic diameters were gradually increased, and statistical significance appeared as early as 8 weeks. We clearly described the process of establishing a hybrid model of atherosclerosis and acute colitis, which might provide a repeatable platform for the interaction mechanism exploring and drug screening of atherosclerosis and inflammatory bowel disease in preclinical study.

Jugular venous flow dynamics during acute weightlessness.

During spaceflight, fluids shift headward, causing internal jugular vein (IJV) distension and altered hemodynamics, including stasis and retrograde flow, that may increase the risk of thrombosis. This study's purpose was to determine the effects of acute exposure to weightlessness (0-G) on IJV dimensions and flow dynamics. We used two-dimensional (2-D) ultrasound to measure IJV cross-sectional area (CSA) and Doppler ultrasound to characterize venous blood flow patterns in the right and left IJV in 13 healthy participants (6 females) while 1) seated and supine on the ground, 2) supine during 0-G parabolic flight, and 3) supine during level flight (at 1-G). On Earth, in 1-G, moving from seated to supine posture increased CSA in both left (+62 [95% CI: +42 to 81] mm2, P < 0.0001) and right (+86 [95% CI: +58 to 113] mm2, P < 0.00012) IJV. Entry into 0-G further increased IJV CSA in both left (+27 [95% CI: +5 to 48] mm2, P = 0.02) and right (+30 [95% CI: +0.3 to 61] mm2, P = 0.02) relative to supine in 1-G. We observed stagnant flow in the left IJV of one participant during 0-G parabolic flight that remained during level flight but was not present during any imaging during preflight measures in the seated or supine postures; normal venous flow patterns were observed in the right IJV during all conditions in all participants. Alterations to cerebral outflow dynamics in the left IJV can occur during acute exposure to weightlessness and thus, may increase the risk of venous thrombosis during any duration of spaceflight.NEW & NOTEWORTHY The absence of hydrostatic pressure gradients in the vascular system and loss of tissue weight during weightlessness results in altered flow dynamics in the left internal jugular vein in some astronauts that may contribute to an increased risk of thromboembolism during spaceflight. Here, we report that the internal jugular veins distend bilaterally in healthy participants and that flow stasis can occur in the left internal jugular vein during acute weightlessness produced by parabolic flight.

Incidence rate of venous thrombosis in women switching combined oral contraceptives: a cohort study

BackgroundThe incidence rate of venous thrombosis (VT) in women switching combined oral contraceptives (COCs) is unknown. ObjectivesWe hypothesize that women switching COCs may have a similar increased incidence rate of VT as women who start COCs. Switching means starting with a new COC, which may biologically approximate starting. MethodsWe conducted a cohort study with data from the Netherlands and Denmark. First, we identified starters who were defined as women who did not use COCs in the 2 years prior to the start of their first COC prescription within the study period. Switchers were a subset of COC starters who redeemed a COC formulation different from their initial COC during follow-up but not longer than 12 months after starting. We estimated incidence rate ratios (adjusted incidence rate ratio [aIRR]) of VT with 95% CIs among COC switchers as compared with COC starters using Poisson regression adjusted for age, COC progestogen generation, and preexisting obesity. ResultsIn both countries, we found an increased risk of VT among switchers as compared with starters during the first 3 months of the follow-up (aIRR = 1.77; 95% CI, 1.22-2.56 in the Netherlands and aIRR = 1.50; 95% CI, 1.04-2.16 in Denmark). ConclusionSwitchers, particularly in the first 3 months after switching, may experience a renewed starter effect thereby increasing the risk of VT.

Incidence and clinical progression of asymptomatic peripherally inserted central catheter–related thrombosis in solid neoplasm patients: ultrasound insights from a prospective cohort study

BackgroundManaging central venous catheters in patients with neoplasms is challenging, and peripherally inserted central catheter PORT (PICC-PORT) has emerged as a promising option for safety and efficacy. However, understanding the clinical progression of catheter-related thrombosis (CRT) in cancer patients with central venous catheters remains limited, especially in certain neoplasm types associated with a higher risk of venous thrombosis. ObjectivesThis study aims to assess the effectiveness of ultrasound-guided management in detecting and treating asymptomatic CRT in cancer patients with PICC. MethodsIn this prospective cohort study of 120 patients with solid neoplasms receiving chemotherapy, we investigated the incidence of isolated upper-extremity superficial vein thrombosis, upper-extremity deep vein thrombosis, and fibrin sheath formation through ultrasound follow-up at 30 and 90 days after catheter insertion. We analyzed risk factors associated with CRT and compared incidence rates between PICC-PORT and traditional PICC. ResultsAmong the cohort, 69 patients (57.5%) had high-risk thromboembolic neoplasm, and 31 cases (25.8%) of CRT were observed, mostly within 30 days, with only 7 cases (22.6%) showing symptoms. Traditional PICC use (odds ratio, 5.86; 95% CI, 1.14-30) and high-risk thromboembolic neoplasm (odds ratio, 4.46; 95% CI, 1.26-15.81) were identified as independent risk factors for CRT. ConclusionThe majority of CRT present asymptomatically within the first 30 days of venous catheter insertion in patients with solid neoplasms. Ultrasound follow-up is valuable for detecting asymptomatic CRT. The risk of CRT was lower with PICC-PORT than with PICC. Additionally, the risk of CRT was found to be higher in patients with high-risk thromboembolic neoplasms. It is crucial for larger studies to confirm the utility of treating asymptomatic thromboses and isolated superficial thrombosis.