Thrombi of Different Pathologies: Implications for Diagnosis and Treatment

Bathing-Related Ischemic Stroke: Association between Stroke Subtype and Cerebral Small Vessel Disease

AIMS

Bathing-related ischemic stroke (BIS) is sometimes fatal. However, its mechanisms and risk factors remain unclear. We aimed to identify the incidence of stroke subtypes in BIS, and clarify the impact of cerebral small vessel disease (CSVD) on BIS.

METHODS

Consecutive patients with ischemic stroke between October 2012 and February 2022 were retrospectively screened. The inclusion criteria were: 1) onset-to-door time within 7 days; and 2) availability of the results of MRI evaluation of CSVD markers during hospitalization. BIS was defined as an ischemic stroke that occurred while or shortly after bathing. We investigated the incidence of the stroke subtype and the correlation between CSVD markers and BIS.

RESULTS

1,753 ischemic stroke patients (1,241 [71%] male, median age 69 years) were included. 57 patients (3%) were included in the BIS group. A higher frequency of large artery atherosclerosis (LAA) (prevalence ratio [PR] 2.069, 95% confidence interval [CI] 1.089 to 3.931, p=0.026) and lower frequency of cardio-embolism (CES) (PR 0.362, 95% CI 0.132 to 0.991, p=0.048) in BIS cases were identified. Moreover, lower periventricular hyperintensity (PVH) Fazekas grade (PR 0.671, 95% CI 0.472 to 0.956, p=0.027) and fewer cerebral microbleeds (CMBs) in deep brain region (PR 0.810, 95%CI 0.657 to 0.999, p=0.049) were associated with BIS cases.

CONCLUSIONS

The BIS group was more likely to develop LAA and less likely to develop CES. Lower PVH grade and fewer CMBs in deep brain region were associated with the development of BIS.

Perioperative Low-Dose Aspirin Management for Planned Clipping Surgery: When, How Long, and With What Precautions?

BACKGROUND AND OBJECTIVE

Perioperative low-dose aspirin (ASA) management for open craniotomy surgery lacked information. We analyze to establish the perioperative ASA strategy to minimize both hemorrhagic and thromboembolic complications.

METHODS

The investigators designed a multicenter retrospective study, which included patients scheduled to have clipping surgery for unruptured intracranial aneurysm. The incidence and risk factors were analyzed for postoperative hemorrhagic complications and major cardio- and cerebrovascular events (MACCEs) within 1 month postoperation.

RESULTS

This study included 503 long-term ASA users of 3654 patients at three tertiary centers. The incidence of hemorrhagic complications and MACCEs was 7.4% (37/503) and 8.8% (44/503), respectively. Older age (>70 years, odds ratio [OR]: 2.928, 95% CI [1.337-6.416]), multiple aneurysms operation (OR: 2.201, 95% CI [1.017-4.765]), large aneurysm (>10 mm, OR: 4.483, 95% CI [1.485-13.533]), and ASA continuation (OR: 2.604, 95% CI [1.222-5.545]) were independent risk factors for postoperative hemorrhagic complications. Intracranial hemorrhage was the only type of hemorrhagic complication that increased in the ASA continuation group (10.6% vs 2.9%, P = .001). Between the ASA continuation and discontinuation groups, the overall incidence of MACCEs was not significantly different (log-rank P = .8). In the subgroup analysis, ASA discontinuation significantly increased the risk of MACCEs in the secondary prevention group (adjusted hazard ratio: 2.580, 95% CI [1.015-6.580]).

CONCLUSION

ASA continuation increased the risk of postoperative intracranial hemorrhage. Simultaneously, ASA discontinuation was the major risk factor for postoperative MACCEs in the high-risk group. Without evidence of intracranial hemorrhage, early ASA resumption was indicated (a total cessation duration <7-10 days) in the secondary prevention group.

Thrombin as target for prevention of recurrent events after acute coronary syndromes

The mechanism underlying thrombus formation in acute coronary syndrome (ACS) involves both platelets and thrombin. While both pathways are targeted in acute care, platelet inhibition has been predominantly administered in the chronic phase, yet thrombin plays a key role in platelet activation and fibrin formation. Among ACS patients, there is also a persistent chronic increase in thrombin generation, which is associated with a higher rate of adverse events. In the setting of post-ACS care with rivaroxaban or vorapaxar, targeting thrombin has been associated with decreased thrombin generation and reduced cardiovascular events, but has been associated with increased bleeding risk. We explored the evidence supporting thrombin generation in the pathophysiology of recurrent events post-ACS and the role of thrombin as a viable therapeutic target. One specific target is factor XI inhibition, which is involved in thrombin generation, but may also allow for the preservation of normal hemostasis.

White blood cell subtypes and neutrophil extracellular traps content as biomarkers for stroke etiology in acute ischemic stroke clots retrieved by mechanical thrombectomy

BACKGROUND

Lymphocytes, macrophages, neutrophils, and neutrophil extracellular traps (NETs) associate with stroke risk factors and form a thrombus through different mechanisms. We investigated the total WBCs, WBC subtypes and NETs composition in acute ischemic stroke (AIS) clots to identify possible etiological differences that could help us further understand the process of thrombosis that leads to AIS.

METHODS

AIS clots from 100 cases each of atherothrombotic (AT), cardioembolic (CE) and cryptogenic stroke etiology were collected per-pass as part of the CÚRAM RESTORE registry of AIS clots. Martius Scarlet Blue stain was used to identify the main histological components of the clots. Immunohistochemical staining was used to identify neutrophils, lymphocytes, macrophages, and NETs patterns. The cellular and histological components were quantified using Orbit Image Analysis software.

RESULTS

AT clots were larger, with more red blood cells and fewer WBCs than CE clots. AT clots had more lymphocytes and cryptogenic clots had fewer macrophages than other etiologies. Most significantly, CE clots showed higher expression of neutrophils and extracellular web-like NETs compared to AT and cryptogenic clots. There was also a significantly higher distribution of web-like NETs around the periphery of the CE clots while a mixed distribution was observed in AT clots.

CONCLUSION

The difference in neutrophil and NETs expression in clots from different etiologies may provide insight into the mechanism of clot formation.

Deep and infratentorial cerebral microbleeds are related to wake-up stroke by large-artery atherosclerosis and cardioembolism

BACKGROUND AND AIMS

Circadian variability of blood pressure (BP) and hypercoagulation in the morning have been proposed as underlying mechanisms of wake-up stroke (WUS). The aim was to determine the impact of cerebral microbleeds (CMBs), showing BP fluctuation and background hypercoagulability, on WUS.

METHODS

Consecutive patients with acute ischemic stroke onset-to-door time within one week were screened. WUS was defined as an ischemic stroke that occurred during sleep at night. CMBs were categorized into three: "strictly Lobar", "strictly Deep (D) and/or Infratentorial (I)", and "Mixed". Moderate to severe CMBs were defined as having more than three in total. First, whether CMBs are associated with WUS was examined. Second, the same analysis was performed according to the stroke subtype classified as large-artery atherosclerosis (LAA), cardioembolism (CE), and small-vessel occlusion (SVO).

RESULTS

A total of 1477 patients (1059 [72%] male, median age 69 years) were included, and WUS was observed in 363 (25%) patients. On Poisson regression analysis with a robust variance estimator in the total cohort, moderate to severe strictly D and/or I CMBs (PR 1.505, 95% CI 1.154-1.962, p = 0.003) were associated with WUS. From the perspective of stroke subtype, the same result was confirmed in LAA (PR 2.223, 95% CI 1.036-4.768, p = 0.040) and CE (PR 1.668, 95% CI 1.027-2.709, p = 0.039), not SVO.

CONCLUSIONS

The presence of moderate to severe strictly D and/or I CMBs might be associated with the development of WUS. By stroke subtype, the same result was confirmed in LAA and CE.

Coronary atherosclerotic plaque phenotype and physiopathologic mechanisms: Is there an influence of sex? Insights from intracoronary imaging

Coronary artery disease (CAD) is the leading cause of disability and death in both women and men; considerable differences in clinical presentation, natural history and prognosis are reported between sexes. Different pathophysiological mechanisms play a major role, including sex-related and gender-related features or a combination of both. Reports from intracoronary imaging studies pointed towards morphological plaque features, which seemed to differ between men and women, albeit results reported so far were not conclusive. The purpose of this review is to shed light on differences in the pathophysiology underlying CAD in women vs men including the description of coronary plaque phenotype and mechanisms of plaque instability, as assessed by intracoronary imaging. We will also discuss potential clinical implications with the aim to move towards a sex and gender-based personalized approach in CAD patients.

Using an age and fibrinogen levels adjusted D-dimer cutoff significantly improves the specificity of two equivalent D-dimer assays for excluding pulmonary embolism

OBJECTIVES

Our single-center prospective study compared two methods of D-dimer determination used in the exclusion of pulmonary embolism: bioMérieux method, VIDAS® D-Dimer Exclusion™ II, and Diagnostica Stago method, STA®-Liatest® D-Di Plus. For each of these two methods, we calculated optimized variable cutoffs based on fibrinogen and/or age to improve the specificity of the methods.

PATIENTS - METHODS

2530 patients admitted to the Emergency Department of the Brest University Hospital for suspected pulmonary embolism were included in this study. The comparison of the two methods was performed by calculating their different characteristics: sensitivity, specificity and negative predictive value for different cutoffs systems: fixed or age-adjusted according to Douma et al. An optimization of the variable cutoff according to age and fibrinogen was then performed.

RESULTS

The two methods VIDAS and STAGO are approximately equivalent in terms of performance even if the STAGO method presents a better specificity (57.1 %) at the fixed cutoff of 0.5 μg/mL. The adoption of age-adjusted, fibrinogen-adjusted or doubly-adjusted (age and fibrinogen) cutoffs, significantly improves the specificity of the tests without affecting their excellent sensitivity. These specificities peak respectively at 75.8 % and 76 % for the VIDAS and STAGO tests when using a doubly-adjusted, age and fibrinogen, cutoff, i.e. a gain in specificity of approximately 10 % compared with the age-adjusted cutoff of Douma et al. and of approximately 20 % compared with the fixed cutoff of 0.5 μg/mL.

CONCLUSION

Adopting an optimized variable cutoff based on fibrinogen and/or age significantly improves specificity of D-dimer methods for pulmonary embolism exclusion.

Global coagulation assays in patients with chronic kidney disease and their role in predicting thrombotic risk

BACKGROUND

Despite cardiovascular diseases and thrombosis being major causes of death in patients with chronic kidney disease (CKD), there remains no effective biomarker to predict thrombotic risk in this population.

OBJECTIVE

To evaluate global coagulation assays in patients with CKD and correlate the biomarkers to clinical outcomes.

MATERIAL AND METHODS

Patients with eGFR<30 mL/min/1.73m² were recruited (n = 90) in this prospective observational study. Blood samples were collected for global coagulation assays, including thromboelastography, calibrated automated thrombogram (CAT), overall hemostatic potential (OHP) and tissue factor pathway inhibitor (TFPI).

RESULTS

Following adjustment for age and gender, CKD subjects (mean age 66 years, 36 % female) had increased maximum amplitude on thromboelastography (70.1 vs 60.2 mm, p < 0.001), higher peak thrombin (233.2 vs 219.7 mm, p = 0.030) and increased OHP (16.1 vs 6.4 units, p < 0.001) compared to healthy controls (n = 153). TFPI was also increased in CKD patients (36.4 vs 14.5 ng/mL, p < 0.001). Compared to hemodialysis patients (n = 43), peritoneal-dialysis patients (n = 25) had more hypercoagulable parameters. Thirty-five CKD patients reported thrombotic complications - key predictors included dialysis, higher fibrinogen, reduced endogenous thrombin potential, elevated D-dimer and increased TFPI. Using the dialysis cohort, the predictive risk model based on the key predictors performed better than Framingham heart score and number of cardiovascular risk factors (Harrell's C-stat 0.862 vs 0.585 vs 0.565).

CONCLUSION

CKD appears to confer a hypercoagulable state compared to healthy controls. Interestingly, reduced thrombin generation and raised TFPI was paradoxically associated with increased thrombotic risks, highlighting possible complex compensatory mechanisms within the coagulation system, which may be important in predicting clinical outcomes.

Endovascular thrombectomy or bridging therapy in minor ischemic stroke with large vessel occlusion

BACKGROUND

Whether direct endovascular thrombectomy (EVT) is non-inferior to bridging therapy (intravenous thrombolysis [IVT] followed by EVT) in minor acute ischemic stroke due to large vessel occlusions (AIS-LVO) is not clear. Therefore, this study aimed to assess whether direct EVT is non-inferior to bridging therapy in minor AIS-LVO.

METHODS

903 patients with acute ischemic stroke due to large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) score <6 receiving EVT treatment were enrolled at Bigdata Observatory Platform for Stroke of China in China from January 1, 2019, to December 31, 2020, with final follow-up on March 31, 2021. The primary efficacy endpoint was a favorable outcome defined as a modified Rankin Scale score of 0 to 2 at three months. In addition, there were three prespecified secondary efficacy endpoints, including symptomatic intracerebral hemorrhage (ICH), in-hospital mortality, and mortality by month 3.

RESULTS

A total of 662 patients treated with direct EVT (age 65.9 ± 10.5 years, 71.5 % male, NIHSS score 2.4 [standard deviation {SD}. 1.8]) were compared to 241 bridging-treated patients (age 65.7 ± 10.8, 75.9 % female, NIHSS score 2.5 [1.8]). The rate of symptomatic ICH in the EVT group was lower than in the bridging group (4.2 % vs. 8.3 %; P = 0.02). The in-hospital mortality was not different between the two groups (EVT vs. bridging group: adjusted hazard ratio {HR}, 0.9 [95 % confidence interval {CI}, 0.5 to 1.9]; P = 0.93). There was no significant difference in 3-month poor functional outcome rate (EVT vs. bridging group: 17.1 % vs. 16.2 % [absolute difference, 0.9 % {95 % CI, -0.8 % to 2.4 %}, P = 0.75; adjusted hazard ratio {HR}, 1.0 {95 % CI, 0.6 to 1.7}, P = 0.83]) and mortality rate (13.0 % vs. 11.2 % [absolute difference, 1.5 % {95 % CI, -3.9 % to 6.8 %}, P = 0.47; adjusted HR, 1.1 {95 % CI, 0.8 to 1.9}, P = 0.55]) between those two groups.

CONCLUSION

Among patients with minor AIS-LVO, direct EVT, compared with bridging therapy, met the prespecified statistical threshold for noninferiority for the 3-month prognosis.

Incremental net monetary benefit of direct oral anticoagulants for the prevention of venous thromboembolism after total knee or hip replacement: A systematic review and meta-analysis

INTRODUCTION

This meta-analysis was conducted to quantitatively pool the incremental net benefit (INB) of using direct oral anticoagulants (DOACs) for the prevention of venous thromboembolism (VTE) in patients undergoing total knee or hip replacements (TKR or THR).

MATERIALS AND METHODS

We performed a comprehensive search in several databases published before June 2021. Studies were included if they were cost-effectiveness analyses reporting cost per quality-adjusted life-year or life-year of DOACs compared to low molecular-weight heparins (LMWHs) or other anticoagulant agents for the prevention of VTE after TKR or THR. Risk of bias was also assessed using the biases in economic studies (ECOBIAS) checklist. Various monetary units were converted to purchasing power parity, adjusted to 2020 US dollars. The INBs were pooled across studies using a random-effects model, stratified by high-income countries (HICs) and low- and middle-income countries (LMICs). Heterogeneity was assessed using the I² statistic.

RESULTS

A total of 49 comparisons (TKR = 25 and THR = 24) from 16 studies was included. In HICs, DOACs were cost-effective compared to LMWHs from the health care system/payer perspective for the prevention of VTE after both TKR and THR with corresponding INBs (95 % CI; I²) of $231.91 ($178.71, $285.11; 0 %) and $254.99 ($159.20, $350.77; 27.79 %), respectively. In LMICs, DOACs were not cost-effective compared to LMWHs for both TKR and THR with the INBs of $94.13 (-$40.21, $228.47; 97.04 %) and $80.55 (-$157.37, $318.47; 99.78 %), respectively. No evidence of small-study effects was identified in any analyses. The cost-effectiveness of using DOACs for TKR and THR in HICs was robust across a series of sensitivity analyses.

CONCLUSIONS

DOACs were cost-effective as compared to LMWHs for VTE prophylaxis following TKR and THR surgeries in HICs. Further studies from LMICs are warranted.

Fibrin to von Willebrand factor ratio in arterial thrombi is associated with plasma levels of inflammatory biomarkers and local abundance of extracellular DNA

INTRODUCTION

The composition of thrombi determines their structure, mechanical stability, susceptibility to lysis, and consequently, the clinical outcome in coronary artery disease (CAD), acute ischemic stroke (AIS), and peripheral artery disease (PAD). Fibrin forms the primary matrix of thrombi intertwined with DNA, derived from neutrophil extracellular traps (NETs), and von Willebrand factor (VWF) bridging DNA and platelets. Here we examined the relative content of fibrin, DNA and VWF in thrombi and analyzed their interrelations and quantitative associations with systemic biomarkers of inflammation and clinical characteristics of the patients.

PATIENTS, METHODS

Thrombi extracted from AIS (n = 17), CAD (n = 18) or PAD (n = 19) patients were processed for scanning electron microscopy, (immune)stained for fibrin, VWF and extracellular DNA. Fibrin fiber diameter, cellular components, fibrin/DNA and fibrin/VWF ratios were measured.

RESULTS

Patients' age presented as a strong explanatory factor for a linear decline trend of the VWF content relative to fibrin in thrombi from CAD (adjusted-R² = 0.43) and male AIS (adjusted-R² = 0.66) patients. In a subgroup of CAD and PAD patients with dyslipidemia and high (above 80%) prevalence of atherothrombosis a significant correlation was observed between the VWF and DNA content in thrombi (adjusted-R² = 0.40), whereas a 3.7-fold lower linear regression coefficient was seen in AIS patients, in whom the fraction of thrombi of atherosclerotic origin was 57%. Independently of anatomical location, in patients with atherosclerosis the VWF in thrombi correlated with the plasma C-reactive protein levels.

CONCLUSIONS

The observed interrelations between thrombus constituents and systemic inflammatory biomarkers suggest an intricate interplay along the VWF/NET/fibrin axis in arterial thrombosis.

Association of circulating proprotein convertase subtilisin/kexin type 9 concentration, prothrombin time and cardiovascular outcomes: a prospective cohort study

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is considered to have multiple roles in the development of atherosclerosis, which is recently reported to participate in the thrombotic process. We aimed to examine the relationship between PCSK9 concentration, coagulation indexes and cardiovascular events.

METHODS

A total of 2293 consecutive patients with angina-like chest pain and without lipid-lowering drugs treatment were enrolled and followed up for major adverse cardiovascular events (MACEs). Circulating PCSK9 concentration was determined by ELISA. The routine coagulation tests including activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time were performed. The associations between PCSK9 concentration, routine coagulation indicators and MACEs were analyzed.

RESULTS

Patients with high PCSK9 levels had lower PT and APTT levels (all p <  0.05). However, PCSK9 concentration was only independently and negatively correlated with PT (β = - 0.115, p <  0.001). During a mean of 38.3 months, 186 (8.1%) MACEs were occurred. Multiple Cox regression analysis indicated high PCSK9 or low PT levels as risk factors related to MACEs. When the prognosis was analyzed by the combination of PCSK9 and PT levels, patients with high PCSK9 and low PT had higher incidence of MACEs compared to those with low PCSK9 and high PT.

CONCLUSIONS

Our study firstly suggested that PCSK9 concentration was negatively correlated with plasma levels of PT. Furthermore, high PCSK9 and low PT were associated with MACEs and the combination of PCSK9 with PT had an addictive effect on predicting cardiovascular outcomes in patients with chest pain, which was useful for further subdivision of cardiovascular risks.

High-dose versus low-dose 4-factor prothrombin complex concentrate for factor Xa inhibitor reversal in intracranial hemorrhage

BACKGROUND & PURPOSE

4-factor prothrombin complex concentrate (4FPCC) is used off-label for factor Xa (FXa) inhibitor-associated intracranial hemorrhage (ICH). Guideline recommendations provide various 4FPCC dosing regimens for FXa inhibitor reversal in this setting. We evaluated 4FPCC weight-based dosing and outcomes in FXa inhibitor-associated ICH.

METHODS

We conducted a multi-center, retrospective, cohort study of ICH patients between July 2017 and February 2020. Patients were greater than 18 years of age, received 4FPCC, and were taking apixaban, rivaroxaban, or edoxaban. Patients were separated into high- (≥35 units/kg) or low-dose (<35 units/kg) 4FPCC groups. The primary outcome was hemostasis achievement. Secondary outcomes included in-hospital mortality, intensive care unit and hospital length of stay, discharge disposition, and thrombotic events. Outcomes were evaluated with binary logistic regression.

RESULTS

Of 390 patients identified, 89 were included with 74 and 15 in the high- vs low-dose groups, respectively. Mean (SD) age was 76.6 (±10.8) years. Most were taking a FXa inhibitor for atrial fibrillation (76.4%) and apixaban was the most common FXa inhibitor (65.2%). Hemostasis achievement was greater in the high- vs low-dose group (89.2% vs 46.7%; OR 11.2; 95% CI 2.4-52.6, P = 0.002). Thrombotic events were 8.2% and 6.7% in the high vs low-dose groups, respectively (OR 0.8; 95% CI 0.08-8.2, P = 0.87). No statistically significant differences were found in secondary outcomes.

CONCLUSION

In patients with FXa inhibitor-associated ICH, high-dose 4FPCC was associated with increased odds of hemostasis achievement. There was no difference in thrombotic events.

Serum thromboxane B2 but not soluble P-selectin levels identify ischemic stroke patients with persistent platelet reactivity while on aspirin therapy

BACKGROUND

Aspirin non-response due to persistent platelet reactivity has been associated with adverse vascular events. Light transmission aggregometry (LTA), the 'gold standard' for measuring the platelet response to aspirin therapy, is a cumbersome procedure and a simple and reliable alternative is required. Our aim was to explore whether serum thromboxane B2 (sTXB2) and soluble P-selectin can be used to identify patients who are at risk of increased platelet reactivity while on aspirin.

METHODS AND RESULTS

We recruited 293 ischemic stroke patients, taking aspirin for more than seven days, and performed LTA to classify them. Based on therapeutic serum salicylate levels, 63 patients were excluded due to suspected non-compliance, followed by ELISA measurement of TXB2 and P-selectin in serum. Accordingly, patients were classified into 'Responders' (n = 122, 53%), 'Semi-responders' (n = 76, 33%) and 'Non-responders' (n=32, 14%) by LTA. Patients who had platelet aggregation of ≥70% with 10μM ADP and ≥20% with 0.5mM AA were defined as 'Non-responders'. In comparison with 'Responders', 'Non-responders' had 8.63-fold increased risk of secondary vascular events (p = 0.008). ROC curve analysis revealed that sTXB2, at a cut-off level of >4.15 ng/mL, could distinguish the patient group with elevated platelet reactivity with a sensitivity of 84.3% (AUC = 0.84), and was in fair agreement with the LTA-based classification of patients. Soluble P-selectin levels, on the other hand, had no discriminatory ability.

CONCLUSION

We suggest sTXB2 measurement as an alternative to the LTA approach for identifying aspirin-treated ischemic stroke patients who are at risk of enhanced platelet reactivity and subsequent vascular events.

A 2-Year Prospective Study on the Differences in Prognostic Factors for Major Adverse Cardiovascular, Cerebrovascular and Renal Events Between Patients with Mild and Severe Chronic Kidney Disease

Purpose/Method: No studies have reported on prognostic markers in patients with chronic kidney disease (CKD) according to the severity of the disease. Therefore, in this multicenter, prospective trial performed as part of the Gunma CKD SPECT Multicenter Study, we recruited 311 patients with CKD (eGFR < 60 min/mL/1.73 m²) including 50 patients on hemodialysis and followed them for 2 years. The study sample underwent stress ^99mTc-tetrofosmin SPECT for suspected or possible ischemic heart disease. We evaluated the summed stress score (SSS), summed rest score (SRS), summed difference score (SDS) and cardiac function with electrocardiogram-gated SPECT. Then, we compared the differences in prognostic markers for major adverse cardiac, cerebrovascular, and renal events (MACCRE) between patients with mild CKD (30 min/mL/1.73 m² ≤ eGFR <60 min/mL/1.73 m²; n=184) and those with severe CKD (eGFR <30 min/mL/1.73 m²; n=97). Results: Of 281 patients available for analysis, 91 experienced MACCRE. In a multivariate Cox proportional hazards analysis of factors related to MACCRE, in patients with mild CKD the significant prognostic markers were SDS (P=0.002) and end-systolic volume (ESV, P=0.034); and in the patients with severe CKD, they were eGFR (P=0.03) and diabetes-mellitus (DM, P=0.023). Conclusions: Our findings indicate that SDS and ESV are significant prognostic markers for MACCRE in patients with mild CKD and eGFR and DM are significant prognostic markers in patients with severe CKD.

Overview of Aspirin and Platelet Biology

Aspirin (ASA) has historically been one of the most important drugs in cardiology and has long been the cornerstone of antiplatelet therapy. Although its role in acute coronary syndrome remains undisputed, emerging data suggest that reappraisal of the efficacy of long-term ASA in some primary and secondary prevention may be warranted. The aim of this review is to place these new results in the context of previous evidence on aspirin by appraising the current body of evidence on its use of for cardiovascular diseases. This overview first summarizes the history of the discovery of aspirin, as well as its pharmacology and the concept of ASA resistance. We subsequently recapitulate the evidence of ASA on primary prevention and secondary prevention starting from the classical studies in order to serve as an introductory background to the examination of the most recent clinical trials that will be performed in the rest of the articles of this Supplement. Although the benefit of ASA in acute coronary syndrome remains incontrovertible, emerging evidence challenge the universal need for primary prevention, or for lifelong treatment in secondary prevention or all adults with stable coronary disease who are at highest risk for ASA-induced bleeding. The role of aspirin is quickly changing in recent times and this review provides a review for the clinician about the current role of this drug in cardiovascular care.

Effectiveness and safety of direct oral anticoagulants in patients with cancer associated venous thromboembolism

INTRODUCTION

Real-world evidence on the effects of direct oral anticoagulants (DOACs) in patients with cancer associated venous thromboembolism (VTE) is limited. Thus, our population-based cohort study aimed to assess the effectiveness and safety of DOACs compared to the standard of care low-molecular-weight heparin (LMWH) in this vulnerable population.

MATERIALS AND METHODS

Using linked administrative healthcare databases from the province of Québec, Canada, we identified patients with incident VTE from 2012 to 2015 and a cancer diagnosis in the year before the VTE, who initiated treatment with anticoagulants within 30 days after the VTE. Using an active comparator new-user design with an as-treated exposure definition, we compared use of DOACs with use of LMWH. Cox proportional hazards models estimated adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of recurrent VTE, major bleeding, and all-cause mortality. In secondary analyses, we stratified by age and sex.

RESULTS

Overall, 4438 patients with cancer associated VTE initiated treatment with anticoagulants (513 DOACs, 2698 LMWH). During a median follow-up of 0.3 years, and compared with LMWH, DOACs were associated with a decreased risk of recurrent VTE (HR, 0.54; 95% CI, 0.36-0.82) and major bleeding (HR, 0.54; 95% CI, 0.31-0.96). We also observed a decreased risk of all-cause mortality with DOACs compared with LMWH (HR, 0.14; 95% CI, 0.09-0.22). Age and sex did not modify the associations.

CONCLUSIONS

DOACs were associated with improved effectiveness and safety compared with LMWH in patients with cancer related VTE. Unmeasured confounding probably contributed to our findings on all-cause mortality.

Matrine regulates H2O2-induced oxidative stress through long non-coding RNA HOTAIR/miR-106b-5p axis via AKT and STAT3 pathways

Matrine is a main active constituent of Chinese herb Sophora flavescens Ait (Kushen), which has shown various pharmacological effects, and has been reported to exhibit protective effects in heart failure. In the present study, the underlying mechanism of matrine was explored in H₂O₂-induced H9c2 cell line. It was confirmed that matrine could alleviate H₂O₂-induced injury in H9c2 cells. And the down-regulation of long non-coding RNA HOTAIR induced by H₂O₂ could be reversed by treating with matrine. Moreover, overexpression of HOTAIR promoted cell viability and superoxide dismutase (SOD) level, but inhibited cell apoptosis and lactate dehydrogenase (LDH) level. We found that miR-106b-5p was a target of HOTAIR and negatively regulated by HOTAIR. Moreover, up-regulation of miR-106b-5p restored the effects of HOTAIR overexpression on cell viability, apoptosis, and the levels of LDH and SOD. In addition, matrine protected H9c2 cells from H₂O₂-induced injury through HOTAIR/miR-106b-5p axis. Furthermore, we discovered that matrine exerted protective effects on H₂O₂-induced H9c2 cells through activating STAT3 and AKT pathway. In brief, matrine modulated H₂O₂-induced myocardial oxidative stress repair through HOTAIR/miR-106b-5p axis via AKT and STAT3 signaling pathway. Our study may provide a therapeutic target for the therapy of oxidative stress heart diseases.

Sappanone A alleviates hypoxia/reoxygenation-induced cardiomyocytes injury through inhibition of mitochondrial apoptosis and activation of PI3K-Akt-Gsk-3β pathway

Myocardial ischemia reperfusion injury (MIRI) is a complex pathophysiological process involved with the activation of oxidative stress, inflammation and apoptosis. Sappanone A (SA), a homoisoflavanone isolated from the heartwood of Caesalpinia sappan L., could exhibit antioxidant, anti-inflammatory and anti-apoptotic activities. Therefore, we assumed that SA has a potential use for preventing against MIRI. The present study aimed to investigate the effect of SA treatment on MIRI and its mechanism. Cardiomyocytes (H9c2 cells) were treated with SA for 1 h, followed by 6 h of hypoxia/3 h of reoxygenation. Cell viability assay was detected by CCK-8 assay. Apoptosis was measured by flow cytometry and Hoechst staining. Mitochondrial permeability transition pore (mPTP) opening and mitochondrial transmembrane potential (ΔΨm) were measured by spectrophotometry and JC-1 staining. The changes of mitochondrial apoptosis-related proteins and PI3K–Akt–Gsk-3β signaling pathway were evaluated by Western blotting. The results showed that SA pretreatment enhanced the cell viability and decreased the activity of myocardial enzyme in a dose-dependent manner. Moreover, SA pretreatment significantly inhibited apoptosis, blocked mPTP opening, suppressed the release of ΔΨm, prevented the cytochrome c releasing from mitochondria into cytoplasm, and repressed the cleavage of caspase-9 and caspase-3. Furthermore, SA pretreatment increased the phosphorylation levels of Akt and Gsk-3β but not of Stat-3. Meanwhile, the protective effect of SA was abrogated by PI3K inhibitor (LY294002). In conclusion, our results demonstrate that SA could prevent hypoxia/reoxygenation-induced cardiomyocytes injury through inhibition of mitochondrial apoptosis and activation of PI3K–Akt–Gsk-3β pathway. Thus, SA may have a potential use for the prevention of MIRI.

Hemodialysis-related low thrombogenicity measured by total thrombus-formation analysis system in patients undergoing percutaneous coronary intervention

BACKGROUND

Established antithrombotic therapies can increase bleeding risk, especially in hemodialysis (HD) patients. The Total Thrombus-formation Analysis System (T-TAS) is useful for evaluating thrombogenicity. The aim of this study was to examine the relationship between HD and thrombogenicity, or bleeding events in patients undergoing percutaneous coronary intervention (PCI).

METHODS

In this retrospective cohort study, 300 patients undergoing elective PCI were enrolled between April 2017 and March 2019. Blood samples obtained on the day of PCI were analyzed with T-TAS to compute the thrombus formation area under the curve (AUC; PL₁₈-AUC₁₀ for platelet chip; AR₁₀-AUC₃₀ for atheroma chip). The patients were divided into three groups according to estimated glomerular filtration rate (eGFR): 33 HD patients, 124 non-HD patients with eGFR <60 mL/min/1.73m², and 143 non-HD patients with eGFR ≥60. We examined the thrombogenicity and spontaneous bleeding events within 1-year post-PCI.

RESULTS

HD was significantly associated with both low PL₁₈-AUC₁₀ and AR₁₀-AUC₃₀ levels determined by T-TAS. Bleeding events defined by the Bleeding Academic Research Consortium criteria types 2, 3, or 5 occurred during follow-up in 27 patients (9.0%): 7 in HD, 10 in non-HD with eGFR <60, and 10 in non-HD with eGFR ≥60. Both T-TAS parameters in the patients with bleeding were lower compared with those in the patients without bleeding, and HD was significantly associated with 1-year bleeding events.

CONCLUSIONS

The results suggested that HD patients undergoing PCI might be a predictor for low thrombogenicity measured by T-TAS and 1-year bleeding risk.

Diagnostic accuracy of four different D-dimer assays: A post-hoc analysis of the YEARS study

INTRODUCTION

For exclusion of pulmonary embolism (PE) clinical decision rules in combination with a D-dimer assay are applied. Currently available D-dimer assays are not standardized and it is unknown whether these differences have an impact on diagnostic management of suspected PE. Therefore, the aim is to explore differences between D-dimer assays and their impact on diagnostic outcome.

METHODS

Data from all patients included in the YEARS study were collected. The YEARS study is a prospective, multicentre, cohort outcome study evaluating 3462 patients with suspected PE in which four different D-dimer assays were applied (Liatest, Innovance, Tinaquant, Vidas). Median D-dimer concentrations were calculated for each D-dimer assay. Sensitivity, specificity, PPV and NPV for detection of PE of all four assays were determined in patients without YEARS items and in those with ≥1 YEARS items (i.e. symptomatic deep vein thrombosis, haemoptysis, and whether PE is the most likely diagnosis).

RESULTS

A total of 1323, 1100, 768 and 271 D-dimer concentrations were collected using the Liatest Innovance, Tinaquant and Vidas assay, respectively. Median D-dimer concentrations differed significantly between assays, with lowest values in the Tinaquant assay. In patients without YEARS items using a cutoff level of 1000 ng/mL, the NPV varied from 99,5 to 100%. In patients with ≥1 YEARS items using a 500 ng/mL cutoff, the NPV varied from 97,0 to 100% depending on the assay.

CONCLUSIONS

The overall high NPV for all assays demonstrates the clinical value of the D-dimer assay. However, these results confirm differences between D-dimer assays, which have an impact on follow-up imaging. This emphasizes the need for standardization of D-dimer assays.

A diagnosis of atrial fibrillation is not a predictor for pulmonary embolism

BACKGROUND AND OBJECTIVES

Atrial fibrillation causes stroke by embolization of blood clots from the left atrium. This suggests that it also can cause pulmonary embolism through embolization of thrombi from the right atrium. Our objective was to investigate if atrial fibrillation is an independent risk factor for pulmonary embolism.

METHOD

This is a retrospective registry study of a random sample of 1.5 million Swedish residents alive on January 1, 2010 (n = 1,442,028) who were followed until the end of 2017. Information about comorbidity, medication and outcomes was obtained from the Swedish national health registers. The endpoint was a first-time event of pulmonary embolism.

RESULTS

The group with atrial fibrillation was >25 years older (mean) than the group without and had almost three times higher incidence of pulmonary embolism (2.91 and 1.09 per 1000 year at risk, p < 0.001). After adjustment for age and other co-factors, atrial fibrillation without oral anticoagulant protection was not associated with increased risk for pulmonary embolism (HR 1.03, CI 0.94-1.13). Adjustment for the competing risk of dying showed similar results (sHR 0.99, CI 0.70-1.40). The higher rate of pulmonary embolism among patients with atrial fibrillation can be fully explained by differences in age and comorbidity.

CONCLUSION

A diagnosis of atrial fibrillation is not a predictor for pulmonary embolism.

Efficacy and safety of non-vitamin K anticoagulants and warfarin in patients with atrial fibrillation and heart failure: A network meta-analysis

BACKGROUND

To recommend the proper anticoagulant drug and its dose for patients with atrial fibrillation (AF) and heart failure (HF), we conducted a network meta-analysis (NMA) to make the comparisons among non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin with regard to efficacy (stroke or systemic embolism) and safety (major bleeding).

METHODS

We searched PubMed, EMBASE, Web of Science and Cochrane Library with the items: "dabigatran, edoxaban, apixaban, rivaroxaban, warfarin, atrial fibrillation and heart failure" through April 14, 2020, focusing on the RCTs comparing the effect of NOACs to warfarin in patients with AF and HF. The NMA was performed based on R (version3.5.1) recalling JAGS (version4.3.0) with gemtc package. Moreover, NetMetaXL (version1.6.1) and winBUGS (version1.4.3) were employed to obtain the cumulative ranking curve area (SUCRA) of the anticoagulants.

RESULT

There was a high probability that dabigatran150 (SUCRA 0.82) ranked the first for the most effective drug, followed by apixaban (SUCRA 0.81), edoxaban60 (SUCRA 0.57) and rivaroxaban (SUCRA 0.52). However, with respect to safety for preventing major bleeding, edoxaban30 (SUCRA 0.99) ranked as the safest drug, followed by apixaban (SUCRA 0.71), edoxaban 60 (SUCRA 0.59) and dabigatran150 (SUCRA 0.55).

CONCLUSION

Apixaban, edoxaban60 and dabigatran150 were more likely to become the choice for preventing stroke or systemic embolism and major bleeding in patients with AF and HF. Nevertheless, more trials need to be performed to focus on the effect of NOACs on the efficacy outcome due to the sparse data. In addition, caution should be excised over selecting the NOAC and its dose on account of the lacking head-to-head comparisons.

Extracellular vesicles in atrial fibrillation and stroke

BACKGROUND

Atrial fibrillation (AF) is associated with a 5-fold increased risk of thromboembolic stroke. Extracellular vesicles (EVs) convey pathophysiological information and are possible biomarkers for risk of stroke.

METHODS

EVs were measured in 836 patients with AF (of which 280 were stroke cases) selected from the ARISTOTLE trial and in a cohort of unselected 70 year old individuals (n = 1007, reference material). EVs from platelets, leukocytes, erythrocytes and inflammatory endothelial cells were measured using flow cytometry and a solid-phase proximity ligation assay.

RESULTS

Concentrations of EVs were higher in the ARISTOTLE patients than in the PIVUS cohort for all the EV groups except EVs from endothelial cells (p < 0.0001). The distributions of the concentrations of the EVs were similar among the control group and the stroke cases for all of the sources of EVs in the ARISTOTLE study. EVs were modestly correlated with the levels of NT-ProBNP, Cystatin C, GDF-15 and D-dimer. Stronger correlations were found for platelet EVs as well as phosphatidyl serine positive EVs that were correlated with CD40 ligand in the ARISTOTLE study. Leukocyte EVs were correlated with IL-6 in both the ARISTOTLE and the PIVUS study, implicating them in different physiological processes.

CONCLUSIONS

Higher levels of EVs were found in anticoagulated patients with AF and a higher risk of stroke than in a general population of similar age, possibly due to the high disease burden in AF patients. Our data with EVs representing a broad repertoire of activated blood cells in AF patients suggest that EVs are likely not a key mediator of occurrence of stroke in this population.

Prehospital Administration of Unfractionated Heparin in ST-Segment Elevation Myocardial Infarction Is Associated With Improved Long-Term Survival

OBJECTIVE

Administration of unfractionated heparin to STEMI patients by the ambulance service is an established practice in Scotland, but the efficacy is unknown. We studied the effects of unfractionated heparin in STEMI patients treated by primary percutaneous coronary intervention, on infarct artery patency and mortality.

METHODS AND RESULTS

Consecutive patients (n = 1000) admitted to Ninewells Hospital, Dundee, from 2010 to 2014 for primary percutaneous coronary intervention were allocated to 2 groups: 437 (44%) prehospital heparin (PHH) administered by paramedics, and 563 (56%) in-hospital heparin. A trained medical student assessed coronary flow at presentation and collected the data. Mortality status was ascertained at 30 days and 5 years. Cox proportional hazards regression models were generated. The patient groups were similar, although PHH had shorter symptom onset-treatment time (187 vs. 251 minutes, P < 0.001) and less cardiogenic shock (3.9% vs. 8.0%, P = 0.008). Initial coronary flow was not different between the groups. Thirty day mortality in PHH was 2.5% versus 8.3%, P < 0.001. Independent predictors of 30-day mortality were age (odds ratio 1.07, 95% CI 1.04-1.09), cardiogenic shock (5.97, 3.33-10.69), radial access (0.53, 0.28-0.98), and PHH (0.33, 0.17-0.66). Five-year mortality in PHH was 13.0% versus 21.6%, P < 0.001. Significant predictors of long-term mortality were age (1.07, 1.06-1.09), cardiogenic shock (3.40, 2.23-5.17), and PHH (0.68, 0.49-0.96).

CONCLUSIONS

PHH was associated with reduced short- and long-term mortality after adjusting for important potential confounders.

Concomitant assessment of rivaroxaban concentration and its impact on thrombin generation

BACKGROUND

Reliable assays to measure direct oral anticoagulant (DOAC) levels and their activity in critical situations are needed. Drug levels alone are not representative of the effect of DOACs on an individual's coagulation. We developed a technique that provides direct assessment of the global effect of rivaroxaban on the individual's coagulation in addition to plasma concentrations.

METHODS

DOAC concentrations were determined in fifty patients using rivaroxaban, with the new assay, Xross-CAT. The effect of rivaroxaban on coagulation (activity) was measured with thrombin generation (TG) in platelet poor plasma using 5 pM tissue factor on the same device. The levels were validated with the Biophen DiXal assay. The prothrombin time (PT) and dilute Russell viper venom time (dRVVT) were performed to estimate the effect on coagulation.

RESULTS

The variability of Xross-CAT was below 12%. Xross-CAT correlates well with Biophen DiXaI (r_s = 0.885). The bias, determined by Bland-Altman analysis, was 4.9% and the Passing-Bablok equation was y = 1.1x - 2.1. The correlation of plasma levels with TG was moderate (ETP r_s = -0.548; Peak r_s = -0.559), as for the PT (r_s = 0.739) and the dRVVT (r_s = 0.692).

CONCLUSIONS

Xross-CAT shows a good correlation with Biophen DiXaI that was previously confirmed to accurately assess rivaroxaban levels. Bleeding and thrombotic complications are not necessarily associated with drug levels and could be influenced by concomitant risk factors. The main benefit of Xross-CAT is that it can be performed simultaneously with thrombin generation, providing an overview of the global anticoagulation status of a patient in relation to circulating DOAC levels.

Bioprospecting for Antithrombotic Polar Lipids from Salmon, Herring, and Boarfish By-Products

Marine polar lipids (PLs) have exhibited promising cardioprotection. In this study, marine by-products such as salmon heads (SHs), their brain, eyes and main optic nerves (SBEON), and head-remnants after SBEON removal (RemSH), as well as herring fillets (HFs), herring heads (HHs) and minced boarfish (MB), were evaluated as potential sustainable sources of such bioactive PLs. The antithrombotic bioactivities of PLs derived from these marine by-products were assessed for the first time in human platelets against platelet-activating factor (PAF), thrombin, collagen, and adenosine diphosphate (ADP), while their fatty acid composition was evaluated by gas chromatography–mass spectrometry (GC-MS). PLs from all marine by-products tested possess strong antithrombotic activities against aggregation of human platelets induced by all platelet agonists tested. RemSH, SBEON, HHs, HFs, and MB exhibited strong anti-PAF effects, similar to those previously reported for salmon fillets. PLs from MB had the strongest anti-collagen effects and PLs from SHs and SBEON were the most active against thrombin and ADP. PLs from HHs had similar antithrombotic effects with those from HFs in all agonists. RemSH was less active in all agonists, suggesting that SBEON is the main source of bioactive PLs in SHs. All PLs were rich in omega-3 polyunsaturated fatty acids (ω3PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic (EPA) acid, with favourable low values of the ω6/ω3 ratio. Salmon, herring, and boarfish by-products are rich sources of bioactive marine PLs with potent antithrombotic and cardioprotective properties.

Relationship Between HDL Functional Characteristics and Cardiovascular Health and Potential Impact of Dietary Patterns: A Narrative Review

Cardiovascular disease is a leading cause of death around the world. Overall diet quality and dietary behaviors are core contributors to metabolic health. While therapeutic targets have traditionally focused on levels of lipoprotein cholesterol when evaluating cardiovascular risk, current perspectives on high-density lipoprotein (HDL) have shifted to evaluating the functionality of this lipoprotein particle. Effects of diet on cardiovascular health are mediated through multiple pathways, but the impact on HDL composition and function deserves greater attention. Potential areas of investigation involve changes in particle characteristics, distribution, microRNA cargo, and other functional changes such as improvements to cholesterol efflux capacity. Various dietary patterns like the Mediterranean diet and Dietary Approaches to Stop Hypertension (DASH) diet have beneficial effects on cardiovascular health and may prevent cardiovascular events. These healthful dietary patterns tend to be rich in plant-based foods, with cardiovascular benefits likely resulting from synergistic effects of the individual dietary components. The purpose of this review is to summarize current perspectives on selected functions of HDL particles and how various dietary patterns affect cardiovascular health biomarkers, with a focus on HDL functionality.

Most Important Prognostic Values to Predict Major Adverse Cardiovascular, Cerebrovascular, and Renal Events in Patients with Chronic Kidney Disease Including Hemodialysis for 2 Years

Patients with chronic kidney disease (CKD) have an increased risk of adverse cardiovascular/cerebrovascular events. The aim of this study is to clarify whether stress myocardial perfusion single-photon emission computed tomography (SPECT) could predict cardiovascular/cerebrovascular events. In the Gunma-CKD SPECT Study, a multicenter prospective cohort trial, 311 patients with CKD (estimated glomerular filtration rate < 60 min/mL/1.73 m2) including 50 patients on hemodialysis underwent stress 99mTc-tetrofosmin SPECT for suspected ischemic heart disease and were followed for 2 years. The primary endpoint was the occurrence of cardiac death (CD), while the secondary endpoint was major adverse cardiovascular/cerebrovascular and renal events (MACCRE). MACCRE occurred in 91 out of 286 patients (CD in 13 and other MACCRE in 78 patients). According to a multivariate Cox analysis, hemoglobin (Hb) and end-systolic volume (ESV) were associated with CD (p < 0.05), while the summed difference score, diabetes mellitus (DM), and Hb were associated with MACCRE (p < 0.05). Kaplan-Meier analysis showed that the CD-free rate was higher in patients with ESV < 105 mL (log-rank, p = 0.0013), Hb > 12 g (log-rank, p = 0.0036), and a summed stress score < 6 (log-rank, p = 0.0058). The MACCRE-free rate was higher in patients with SDS = 0 (log-rank, p = 0.0097), without DM (log-rank, p = 0.0091), and with Hb > 12 g (log-rank, p = 0.0023). Myocardial perfusion SPECT parameters as well as renal anemia and DM can be reliable prognostic markers in patients with CKD including hemodialysis.

Ginkgolide B ameliorates myocardial ischemia reperfusion injury in rats via inhibiting endoplasmic reticulum stress

Purpose

Ginkgolide B (GB) is a terpene lactone component found in Ginkgo biloba, which has a protective role on ischemia reperfusion (I/R) injury. This study was aimed at exploring the protective mechanism of GB on the myocardial I/R.

Patients and methods

Myocardial I/R model was established on Sprague Dawley rats. The levels of cardiac troponin I, cardiac troponin T, lactic dehydrogenase, and myoglobin were determined by a 200FR NEO automatic biochemical analyzer. Histological examination was performed through HE and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining. The expression levels of p-PERK, p-IRE1α, ATF6, p-AKT, and mTOR were detected by Western blot.

Results

The results exhibited that GB treatment suppressed the high levels of cardiac troponin I, cardiac troponin T, lactic dehydrogenase, and myoglobin and ameliorated the damaged and irregularly arranged myocardial cells induced by I/R injury significantly, indicating that GB could ameliorate myocardial I/R injury. Moreover, the high expression levels of endoplasmic reticulum (ER) stress key proteins caused by I/R injury were suppressed significantly by GB treatment, including p-PERK, p-IRE1α, and ATF6. GB treatment also decreased the number of apoptotic cells compared with I/R group. In addition, activation of ER stress by Tunicamycin treatment could counteract the protective effects of GB on I/R injury, suggesting that GB ameliorated myocardial I/R injury through inhibition of ER stress-induced apoptosis. Finally, the decreased p-AKT and p-mTOR expressions caused by I/R injury were upregulated by GB and inhibition of PI3K/AKT/mTOR pathway by LY294002 abolished the protective effects of GB on I/R injury, indicating that GB activated PI3K/AKT/mTOR pathway during I/R injury.

Conclusion

GB protected against myocardial I/R injury through inhibiting ER stress-induced apoptosis via PI3K/AKT/mTOR signaling pathway.

Rivaroxaban plasma levels in patients admitted for bleeding events: insights from a prospective study

Background

Serious bleeding events have been frequently described in patients taking direct oral anticoagulants (DOAC). In secondary analyses of phase 3 trials, DOAC plasma concentrations were shown to correlate with bleeding outcomes. This study aimed to describe rivaroxaban plasma levels in patients admitted to the emergency department (ED) for bleeding events. For each patient, risk factors for experiencing bleeding events were also investigated.

Methods

This analysis was part of an observational study conducted in the ED of two teaching hospitals. Plasma samples from 10 rivaroxaban-treated patients admitted for bleeding events were collected. Rivaroxaban plasma concentrations were determined by calibrated chromogenic anti-Xa assay. The measured rivaroxaban levels were then extrapolated at trough using a published population pharmacokinetic (PopPK) model, and compared to on-therapy ranges observed in large clinical trials. For each patient, clinical, medication and ABCB1 genotype data were collected.

Results

Rivaroxaban measurements varied from 5 to 358 ng/ml, with a post-intake delay ranging from 9 to 38 h. At trough, estimated plasma concentrations were between 12 and 251 ng/ml (median value 94 ng/ml). Four patients had higher-than-expected rivaroxaban levels. Inadequate dose regimen, excessive alcohol consumption and lack of treatment reassessment were observed in several patients. Half of patients were taking ≥1 drug with potential pharmacokinetics interactions (e.g. amiodarone, diltiazem), while half of patients were taking ≥1 drug increasing the risk of bleeding. All 3 patients with available genotyping data and higher-than-expected rivaroxaban levels were heterozygous or homozygous mutated for the ABCB1 1236C > T, 2677G > T, 3435 C > T and rs4148738 single nucleotide polymorphisms (SNP).

Conclusions

Rivaroxaban patients admitted to the ED for bleeding events showed highly variable plasma concentrations. This analysis underlines the usefulness of rapid DOAC measurement and the value of PopPK models to estimate concentrations at trough in a context where the post-intake delay is unmanageable. Close patient follow-up, including renal function assessment and drug interactions review, is essential for bleeding risk minimization.

Preemptive warfarin dose reduction after initiation of sulfamethoxazole-trimethoprim or metronidazole

To evaluate the utility of a preemptive warfarin dose reduction at the time of initiation of either sulfamethoxazole-trimethoprim or metronidazole, a retrospective chart review of patients who received an outpatient prescription for warfarin and either sulfamethoxazole-trimethoprim and/or metronidazole from July 1, 2011 to July 1, 2015 was conducted. Clinical outcomes compared Veterans who had a warfarin dose reduction and those who did not within 120 h (5 days) of antibiotic initiation. The primary outcome compared the pre-and post-antibiotic International Normalized Ratio (INR) of patients in the intervention group (warfarin dose reduction) with those in the control group (no intervention). Secondary outcomes assessed incidence of thromboembolic and major bleeding events within 30 days of antibiotic completion. Fifty patients were assessed. Forty-nine patients had at least one follow-up appointment; 126 follow-up visits were evaluated. There was a statistically significant difference for the change in therapeutic INR at the first follow-up appointment (p = 0.029) for those patients in the control group. On average, the patients in the intervention group required fewer follow-up visits (p = 0.019). There were no statistically significant differences for the overall rate of therapeutic INR values between groups, as well as no instances of a thromboembolic or major bleeding events during the follow-up period. Clinically significant differences were observed for patients who received a preemptive warfarin dose reduction upon initiation of sulfamethoxazole-trimethoprim or metronidazole. Patients in the intervention group required fewer follow-up appointments and were more likely maintain a therapeutic INR within the 30 days following the antibiotic course. Results of this study will be presented the at Pharmacy and Therapeutics committee in an effort to seek approval for policy development to initiate a local preemptive warfarin dose adjustment as a standard of practice.

Badimon Perfusion Chamber: An Ex Vivo Model of Thrombosis

The Badimon perfusion chamber is an ex vivo model of thrombosis that assesses the thrombogenicity of blood in humans and large animals. It works with native blood thereby excluding any interfering effects of anticoagulants unavoidable with the majority of platelet function testing methodologies. Each variable of the Virchow's triad (blood, blood flow, and endothelial wall) that modulates blood-vessel wall interaction and thrombus formation is incorporated in this perfusion model. These features make this device a valuable tool for the assessment of thrombogenic potential of various diseases and also gauging the efficacy of antithrombotic (anticoagulant and antiplatelet) treatments.

Chronic kidney disease is associated with increased risk of venous thromboembolism recurrence

INTRODUCTION

It is currently unclear whether chronic kidney disease (CKD) and the decrease in renal function can influence the risk of venous thromboembolism (VTE) recurrence.

MATERIALS AND METHODS

We performed an ambispective observational study on 409 patients with a previous episode of VTE. All the patients were included in the retrospective analysis whereas a subgroup of 260 individuals, without history of recurrence and that stopped oral anticoagulation, were then followed-up for a mean of 52.3±20.7months.

RESULTS

At the enrollment, subjects with history of recurrent VTE were prevalently male with higher blood pressure and lower eGFR. Prevalence of CKD (defined as eGFR<60ml/min/1.73m²) was higher in patients with previous VTE recurrence with an adjusted OR of 5.69 (IC95% 2.17-14.90, p<0.001) compared to patients with normal eGFR. Similar findings were obtained from the prospective study where an adjusted 5.32 HR for VTE recurrence was seen in patients with CKD compared to subjects with normal renal function (IC95% 1.49-18.95, p=0.010). An increase in the risk of recurrent VTE was also observed in patients with mild decrease in renal function (eGFR 60-90 vs ≥90ml/min/1.73m² adjusted HR 2.84, IC95% 1.13-7.11, p=0.025). Moreover, a multivariate Cox regression analysis including eGFR as continuous variable showed that renal function decrease was independently associated with the risk of VTE recurrence (p=0.001).

CONCLUSIONS

CKD and mild decrease in renal function are associated with a significant increase in the risk of recurrent VTE.

Reduced platelet hyper-reactivity and platelet-leukocyte aggregation after periodontal therapy

Background

Platelets from untreated periodontitis patients are hyper-reactive and form more platelet-leukocyte complexes compared to cells from individuals without periodontitis. It is not known whether the improvement of the periodontal condition achievable by therapy has beneficial effects on the platelet function. We aimed to assess the effects of periodontal therapy on platelet reactivity.

Methods

Patients with periodontitis (n = 25) but unaffected by any other medical condition or medication were included and donated blood before and after periodontal therapy. Reactivity to ADP or oral bacteria was assessed by flow cytometric analysis of membrane markers (binding of PAC-1, P-selectin, CD63) and platelet-leukocyte complex formation. Reactivity values were expressed as ratio between the stimulated and unstimulated sample. Plasma levels of soluble (s) P-selectin were determined by enzyme-linked immunosorbent assay (ELISA).

Results

Binding of PAC-1, the expression of P-selectin and CD63 in response to the oral bacterium P. gingivalis were lower at recall (1.4 ± 1.1, 1.5 ± 1.2, and 1.0 ± 0.1) than at baseline (2.7 ± 4.1, P = 0.026, 6.0 ± 12.5, P = 0.045, and 2.7 ± 6.7, P = 0.042, respectively). Formation of platelet-leukocyte complexes in response to P. gingivalis was also reduced at recall compared to baseline (1.2 ± 0.7 vs. 11.4 ± 50.5, P = 0.045). sP-selectin levels were significantly increased post-therapy.

Conclusions

In periodontitis patients, the improvement of the periodontal condition is paralleled by a reduction in platelet hyper-reactivity. We suggest that periodontal therapy, as an intervention for improved oral health, can facilitate the management of thrombotic risk, and on the long term can contribute to the prevention of cardiovascular events in patients at risk.

Trial registration

Current Controlled Trials identifier ISRCTN36043780. Retrospectively registered 25 September 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s12959-016-0125-x) contains supplementary material, which is available to authorized users.

The effect of in-hospital acquired thrombocytopenia on the outcome of patients with acute coronary syndromes: A systematic review and meta-analysis

BACKGROUND

In-hospital acquired thrombocytopenia (TP) is relatively common among patients hospitalized with acute coronary syndromes (ACS). However, its effect on short-term and long-term outcomes has yet to be reviewed systematically.

METHODS

We conducted a systematic review and meta-analysis of clinical studies assessing the relationship between new-onset in-hospital TP and adverse outcomes among ACS patients. MEDLINE, Scopus and the Cochrane Library were searched for eligible studies published before March 20, 2016.

RESULTS

Ten studies reporting on a total of 142,161 ACS patients were identified. 8133 patients showed evidence of new-onset TP during the course of their hospitalization. Compared with patients with normal platelet counts, patients with new-onset TP had a prolonged in-hospital stay, significantly higher risk of both short-term mortality (<30days) (Odds ratio (OR) [95% confidence interval (CI)]: 5.58 [3.63-8.57]) and late death (6months to 1year) (OR [95% CI]: 3.45 [2.35-5.07]), as well as a significantly higher risk of major bleeding events in the first 30days (OR [95% CI]: 6.93 [5.13-9.38]). In addition, risk for other secondary cardiovascular endpoints, including recurrent myocardial infarction, stroke, in-hospital heart failure, stent thrombosis and unplanned revascularization was also significantly higher in the TP versus the no TP group.

CONCLUSIONS

Development of TP during the in-hospital management of ACS patients is a significant predictor of both short- and long-term adverse events, including mortality. In the light of this evidence, clinicians should be cautious and closely monitor abnormal platelet counts that present early following an ACS.

Expression of functional tissue factor in activated T-lymphocytes in vitro and in vivo: A possible contribution of immunity to thrombosis?

OBJECTIVE

T-lymphocyte activation plays an important role in the pathophysiology of acute coronary syndromes (ACS). Plaques from ACS patients show a selective oligoclonal expansion of T-cells, indicating a specific, antigen-driven recruitment of T-lymphocytes within the unstable lesions. At present, however, it is not known whether T-cells may contribute directly to thrombosis by expressing functional tissue factor (TF). Accordingly, the aim of the present study was to investigate whether T-cells are able to express functional TF in their activated status.

METHODS

In vitro, CD3(+)-cells, isolated from buffy coats, were stimulated with anti-CD3/CD28 beads, IL-6, TNF-α, IL-17, INF-γ or PMA/ionomycin. Following stimulation, TF expression on cell-surface, at gene and protein levels, as well as its procoagulant activity in whole cells and microparticles was measured. In vivo, TF expression was evaluated in CD3(+)-cells isolated from the aorta and the coronary sinus of ACS-NSTEMI and stable coronary artery disease (SCAD) patients. The presence of CD3(+)-TF(+)cells was also evaluated by immunohistochemistry in thrombi aspirated from ACS-STEMI patients.

RESULTS

PMA/ionomycin and IL-17 plus INF-γ stimulation resulted in a significant TF increase at gene and protein levels as well as at cell-surface expression. This was accompanied by a parallel increase in FXa generation, both in whole cells and in microparticles, indicating that the induced membrane-bound TF was active. Furthermore, transcardiac TF gradient was significantly higher in CD3(+)-cells obtained from ACS-patients compared to SCAD-patients. Interestingly, thrombi from ACS-STEMI patients resulted enriched in CD3(+)-cells, most of them expressing TF.

CONCLUSIONS

Our data demonstrate that activated T-lymphocytes in vitro express functional TF on their membranes, suggesting a direct pathophysiological role of these cells in the thrombotic process; this hypothesis is further supported by the observations in vivo that CD3(+)-cells from coronary circulation of ACS-NSTEMI patients show increased TF levels and that coronary thrombi from ACS-STEMI patients are enriched in CD3(+)-cells expressing TF.

Increase in the Size of an Intracardiac Thrombus during Dabigatran Therapy (110 mg b.i.d.) in an Acute Cardioembolic Stroke Patient

We report a case of atrial fibrillation in a patient in whom a mobile thrombus in the left atrial appendage increased in size after low-dose dabigatran therapy. A 74-year-old man was admitted to our hospital because of sudden onset of right hemiplasia and dysarthria. On admission, his National Institutes of Health Stroke Scale score was three. Axial diffusion-weighted magnetic resonance images and magnetic resonance angiography images showed hyperintense signals in the left front-parietal cerebral cortex without any intracranial stenotic lesions, and acute cardioembolic stroke associated with nonvalvular atrial fibrillation was diagnosed. Transesophageal echocardiography revealed a mobile thrombosis (1.0 × 2.2 cm) in the left atrial appendage, and dabigatran therapy (110 mg b.i.d.) was initiated to prevent stroke recurrence. Transesophageal echocardiography performed 6 days later revealed that the size of the thrombus had increased to 1.5 × 3.0 cm. Medication was changed to warfarin, and the thrombosis subsequently decreased in size. The patient did not have a recurrent stroke and was discharged with a National Institutes of Health Stroke Scale score of zero. This case demonstrates that low-dose dabigatran may not be effective in reducing the size of a thrombus.

Expression of proinflammatory, proatherogenic genes is reduced by the Mediterranean diet in elderly people

Ageing is an important determinant of atherosclerosis development rate, mainly by the creation of a chronic low-grade inflammation. Diet, and particularly its fat content, modulates the inflammatory response in the fasting and postprandial states. Our aim was to study the effects of dietary fat on the expression of genes related to inflammation (NF-κB, monocyte chemoattractant protein 1 (MCP-1), TNF-α and IL-6) and plaque stability (matrix metalloproteinase 9, MMP-9) during the postprandial state of twenty healthy, elderly people who followed three diets for 3 weeks each: (1) Mediterranean diet (Med Diet) enriched in MUFA with virgin olive oil; (2) SFA-rich diet; and (3) low-fat, high-carbohydrate diet enriched in n-3 PUFA (CHO-PUFA diet) by a randomised crossover design. At the end of each period, after a 12-h fast, the subjects received a breakfast with a composition similar to the one when the dietary period ended. In the fasting state, the Med Diet consumption induced a lower gene expression of the p65 subunit of NF-κB compared with the SFA-rich diet (P = 0·019). The ingestion of the Med Diet induced a lower gene postprandial expression of p65 (P = 0·033), MCP-1 (P = 0·0229) and MMP-9 (P = 0·041) compared with the SFA-rich diet, and a lower gene postprandial expression of p65 (P = 0·027) and TNF-α (P = 0·047) compared with the CHO-PUFA diet. Direct plasma quantification mostly reproduced the findings. Our data suggest that consumption of a Med Diet reduces the postprandial inflammatory response in mononuclear cells compared with the SFA-rich and CHO-PUFA diets in elderly people. These findings may be partly responsible for the lower CVD risk found in populations with a high adherence to the Med Diet.