Patients on Antithrombotic Agents with Small Bowel Bleeding -Yield of Small Bowel Capsule Endoscopy and Subsequent Management

BACKGROUND AND AIMS

Small bowel gastrointestinal bleeding (GIB) is associated with multiple blood transfusions, prolonged and/or multiple hospital admissions, utilization of significant healthcare resources, and negative effects on patient quality of life. There is a well-recognized association between antithrombotic medications and small bowel GIB. We aimed to identify the diagnostic yield of small bowel capsule endoscopy (SBCE) in patients on antithrombotic medications and the impact of SBCE on treatment course.

METHODS

The electronic medical records of nineteen hundred eighty-six patients undergoing SBCE were retrospectively reviewed.

RESULTS

The diagnostic yield for detecting stigmata of recent bleeding and/or actively bleeding lesions in SBCE was higher in patients that were on antiplatelet agents (21.6%), patients on anticoagulation (22.5%), and in patients that had their SBCE performed while they were inpatient (21.8%), when compared to the patients not on antiplatelet agents (12.1%), patients not on anticoagulation (13.5%), and with patients that had their SBCE performed in the outpatient setting (12%). Of 318 patients who had stigmata of recent bleeding and/or actively bleeding lesion(s) identified on SBCE, SBCE findings prompted endoscopic evaluation (small bowel enteroscopy, esophagogastroduodenoscopy (EGD), and/or colonoscopy) in 25.2%, with endoscopic hemostasis attempted in 52.5%.

CONCLUSIONS

Our study, the largest conducted to date, emphasizes the importance of performing SBCE as part of the evaluation for suspected small bowel bleeding, particularly in patients taking antithrombotic therapy, and especially during their inpatient hospital stay.

Non-valvular atrial fibrillation in patients on peritoneal dialysis, prevalence, treatment and professionals involved

Atrial fibrillation is the most frequent chronic arrhythmia in patients with chronic kidney disease. Oral anticoagulation with vitamin K antagonists and now direct oral anticoagulants have been and are the fundamental pillars for the prevention of thromboembolic events. However, there are no randomized clinical trials on the risk-benefit profile of oral anticoagulation in patients with chronic kidney disease stage 5 on peritoneal dialysis and there is little evidence in the literature in this population. The objective of our study was to know the prevalence, treatment and professionals involved in the management of atrial fibrillation in peritoneal dialysis patients. For this purpose, we performed a descriptive analysis through a survey sent to different peritoneal dialysis units in Spain. A total of 1,403 patients on peritoneal dialysis were included in the study, of whom 186 (13.2%) had non-valvular atrial fibrillation. In addition, the assessment of the scores of thromboembolic and bleeding risks for the indication of oral anticoagulation was mainly carried out by the cardiologist (60% of the units), as well as its prescription (cardiologist 47% or in consensus with the nephrologist 43%). In summary, patients on peritoneal dialysis have a remarkable prevalence of non-valvular atrial fibrillation. Patients frequently receive oral anticoagulation with vitamin K antagonists, as well as direct oral anticoagulants. The data obtained regarding the scores used for the assessment of thromboembolic and bleeding risk, treatment and involvement by Nephrology indicates that there is a need for training and involvement of the nephrologist in this pathology.

Management of Anticoagulant and Antiplatelet Agents in Acute Gastrointestinal Bleeding and Prevention of Gastrointestinal Bleeding

Managing gastrointestinal bleeding in patients using antithrombotic agents remains challenging in clinical practice. This review article provides a comprehensive and evidence-based approach to managing acute antithrombotic-related gastrointestinal bleeding, focusing on the triage of patients, appropriate resuscitation, and timely endoscopy. The latest clinical practice guidelines are highlighted to guide decisions concerning the use of reversal agents, temporary interruption, and resumption of antithrombotic drugs. Additionally, preventive measures are discussed to lower the risk of future bleeding and minimize complications among patients prescribed antithrombotic drugs.

Effects of thienopyridine class antiplatelets on bleeding outcomes following robot-assisted radical prostatectomy

This study aimed to assess the effects of thienopyridine-class antiplatelet agents (including ticlopidine, clopidogrel, and prasugrel) on bleeding complications in patients who underwent robot-assisted radical prostatectomy. This cohort study used a database for robot-assisted radical prostatectomy at 23 tertiary centers nationwide between 2011 and 2022. Patients who received thienopyridines (thienopyridine group) were compared with those who received aspirin monotherapy (aspirin group). The primary outcome was the incidence of bleeding complications. High-grade complications were defined as Clavien-Dindo grade III or higher. The risks of these outcomes were evaluated using inverse probability of treatment weighted regression models. The study results demonstrated that thienopyridine therapy was associated with a higher risk of overall bleeding complications (OR: 3.62, 95%CI 1.54-8.49). The increased risks of the thienopyridine group were detected for low-grade bleeding complications (OR: 3.20, 95%CI 1.23-8.30) but not for high-grade bleeding complications (OR: 5.23, 95%CI 0.78-34.9). The increased risk of bleeding complications was not observed when thienopyridine was discontinued (OR: 2.52, 95%CI 0.83-7.70); however, it became apparent when it was continued perioperatively (OR: 4.35, 95%CI 1.14-16.61). In conclusion, thienopyridine increased the incidence of bleeding complications, particularly low-grade bleeding complications, following robot-assisted radical prostatectomy. These bleeding effects emerged when thienopyridine was continued perioperatively.

[Survey on blood thinning therapy in patients with age-related macular degeneration]

BACKGROUND

Patients with age-related macular degeneration (AMD) often receive concomitant systemic blood thinning medications. These are known to increase the risk of severe hemorrhage also in connection with AMD, which can lead to extensive subretinal hemorrhaging.

OBJECTIVE

The purpose of this study was to investigate the proportion of patients with AMD and concomitant blood thinning treatment, including the type and reason for blood thinning treatment.

METHODS

This survey was prospectively conducted at the University Eye Hospital, Bonn, Germany. Volunteers were recruited during retinal consultations and the consultations for intravitreal injections (IVOM).

RESULTS

The questionnaire was completed by 178 patients. The mean age was 81.7 years (58-100) and 101 patients (57.7%) were undergoing blood thinning treatment. The majority of patients were taking antiplatelet agents (n = 59; 58.4%), especially ASA (n = 55; 54.5%). Direct oral anticoagulants (DOAC) were taken by 33 patients (32.7%), including most frequently apixaban (17.8%). Vitamin K antagonists (VKA) was taken by 4 patients (4%). The most common reason for blood thinning treatment was atrial fibrillation (n = 32, 31.7%), followed by stent implantation (n = 20, 19.8%) and stroke (n = 12, 11.9%) but 13 patients (12.9%) did not know why they were undergoing blood thinning treatment. No clear indications for the use of blood thinners were found in 31 patients (30.7%).

CONCLUSION

A large proportion of patients with AMD undergo blood thinning treatment; however, not every patient has a clear indication. Due to the increased risk of bleeding, the use of blood thinners should be critically evaluated in close cooperation with primary care physicians and cardiologists.

Effects of preceding antiplatelet agents on severity of ischemic stroke in patients with a history of stroke

INTRODUCTION

Antiplatelet agents are effective for secondary prevention of ischemic stroke and can reduce the severity of first-ever ischemic stroke. However, it is uncertain if prophylactic antiplatelet therapy reduces the severity of recurrent ischemic stroke. The aim of this study was to determine the effect of preceding antiplatelet treatment on the severity of thrombotic stroke (TS) in patients with a prior history of stroke.

METHODS

From a prospective hospital registry of 1338 consecutive patients with acute ischemic stroke, we identified patients with a prior history of stroke who were admitted for cardioembolic stroke (CE); TS including large-artery atherosclerosis, small vessel occlusion, and branch atheromatous disease; or other cause or cryptogenic stroke (OCS). Cases in each subtype were categorized based on preceding medication: antiplatelet agents (AP) and none (N). Severity of stroke (National Institutes of Health Stroke Scale: NIHSS) on admission was compared between AP and N cases.

RESULTS

The total cohort of 252 patients included 83 with CE, 102 with TS, and 67 with OCS. After excluding those with prior anticoagulants, the median NIHSS on admission was lower in AP cases than in N cases (3 vs. 5, p = 0.002). In multivariate analysis, preceding AP treatment was independently associated with minor stroke (NIHSS ≤4) on admission in CE group (OR 8.48, 95% CI 1.71-62.9, p = 0.008) and TS group (OR 4.24, 95% CI 1.44-13.4, p = 0.009).

CONCLUSION

Preceding antiplatelet treatment in patients with a prior history of stroke may reduce the severity of subsequent thrombotic and cardiogenic stroke.

Prognostic Comparison of Octogenarian vs. Non-Octogenarian With Acute Decompensated Heart Failure - AURORA Study

BACKGROUND

Acute decompensated heart failure (ADHF) is the main cause of hospitalization and death of octogenarians, but no data on the 1-year post-discharge mortality rate. We evaluated the clinical status and predictors of 1-year mortality in octogenarians with ADHF.Methods and Results: From the AURORA (Acute Heart Failure Registry in Osaka Rosai Hospital) study, we examined 1,246 hospitalized ADHF patients. We compared the in-hospital mortality rate and the proportion of heart failure (HF) with preserved ejection fraction (HFpEF) between octogenarians and non-octogenarians. After discharge we compared the 1-year mortality rate between these groups, and we also evaluated the predictors of death in both groups. The proportion of HFpEF among the in-hospital deaths of octogenarians was significantly higher than in non-octogenarians (46.2% vs. 15.0%, P=0.031). The 1-year mortality rate after discharge was significantly higher in the octogenarians than non-octogenarians (P=0.014). Multivariable Cox regression analysis revealed that albumin ≤3.0 g/dL and antiplatelet agents were useful predictors of 1-year death after discharge of octogenarians whereas chronic kidney disease was a predictor in the non-octogenarians.

CONCLUSIONS

The proportion of HFpEF among in-hospital deaths of octogenarians with ADHF was high as compared with non-octogenarians. When octogenarians with ADHF have severe hypoalbuminemia and antiplatelet agents, early nutritional and medical interventions after discharge may be important to improve the 1-year prognosis.

Advances and Perspectives in methods for identifying high platelet reactivity

Antiplatelet therapy is the foundational treatment for the prevention and treatment of coronary and cerebrovascular ischemic events in patients with coronary heart disease, ischemic stroke, and transient ischemic attack (TIA). However, with more and more studies reporting an increased risk of thrombosis in some patients due to poor response to therapeutic agents, the selection of appropriate P2Y12 inhibitors has become a major challenge that needs to be addressed urgently. Currently, commonly used oral P2Y12 inhibitors include clopidogrel, ticagrelor, and prasugrel. Assessing patients' risk factors before the development of treatment regimens by effectively predicting the risk of high platelet reactivity with specific P2Y12 inhibitors in advance to avert the occurrence of major adverse cardiovascular and cerebrovascular events (MACCE) is the key point to the problem. Up to now, methods available for predicting platelet reactivity include genetic testing, platelet function testing, and risk scores. This review provides a summarization of the existent available identification methods and analyzes the advantages and drawbacks of different methods in specific clinical settings, intending to guide the rational clinical application of P2Y12 receptor inhibitors.

Anticoagulation and Antiplatelet Agent Resumption Timing following Traumatic Brain Injury

Traumatic brain injury (TBI) is a major global health concern. Due to the increase in TBI incidence and the aging population, an increasing number of patients with TBI are taking antithrombotic agents for their underlying disease. When TBI occurs in patients with these diseases, there is a conflict between the disease, which requires an antithrombotic effect, and the neurosurgeon, who must minimize intracranial hemorrhage. Nevertheless, there are no clear guidelines for the reversal or resumption of antithrombotic agents when TBI occurs in patients taking antithrombotic agents. In this review article, we intend to classify antithrombotic agents and provide information on them. We also share previous studies on the reversal and resumption of antithrombotic agents in patients with TBI to help neurosurgeons in this dilemma.

Outcome and risk of hemorrhage in patients with tandem lesions after endovascular treatment: A propensity score-matched case-control study

Objectives

Endovascular treatment of acute stroke patients with large vessel occlusions is well established. But tandem lesions of the internal carotid artery and the intracranial anterior circulation remain a challenge regarding the technical conditions and the putative higher risk of hemorrhage due to often required antiplatelet therapy.This study aims to evaluate the clinical outcome and the risk of hemorrhage after endovascular treatment of tandem lesions, with special regard to the periprocedural antiplatelet regimen.

Materials and Methods

In this retrospective study, we included 63 consecutive stroke patients with endovascular treated tandem lesions. One hundred eleven patients with a solitary intracranial occlusion were matched using a "propensity score-matched analysis" with the covariates sex, age, wake-up stroke, iv-thrombolysis and NIHSS.

Results

Rates of successful recanalization (mTICI 2b/3) and periprocedural complications were equal in both groups (P = 0.19; P = 0.35). The rate of good clinical outcome (mRS≤2) was similar, and the incidence of symptomatic hemorrhages was not significantly different (7.9% tandem lesions vs. 5.4% isolated intracranial occlusion, P = 0.51). Even intensified antiplatelet therapy in patients with tandem lesions did not increase the rate of symptomatic intracranial hemorrhages (P = 0.87).

Conclusions

Clinical outcome and symptomatic intracranial hemorrhages did not differ significantly between endovascular treated patients with tandem lesions and matched patients with solitary intracranial occlusions, regardless of the antiplatelet regimen. Therefore, the complex technical requirements for recanalization of a tandem lesion and the putative higher risk should not result in reluctant treatment that would decrease the chance of a good clinical outcome.

Antiplatelet Agents and Oral Anticoagulant Use in Patients with Atrial Fibrillation and Carotid Artery Disease After First-Time Ischaemic Stroke

INTRODUCTION

People with atrial fibrillation (AF) frequently have competing mechanisms for ischaemic stroke, including extracranial carotid atherosclerosis. The objective of this study was to determine associations between use of oral anticoagulants (OACs) plus antiplatelet agents (APA) after ischaemic stroke and outcomes for patients with AF and carotid artery disease.

PATIENTS AND METHODS

A retrospective cohort study was conducted. Participants receiving OACs with or without APA were propensity score-matched for age, sex, ethnicity, co-morbidities and presence of cardiac and vascular implants and grafts. Outcomes were 1-year mortality, recurrent stroke and major bleeding.

RESULTS

Of 5708 patients, 24.1% (n=1628) received non-vitamin K antagonist OACs (NOACs) with no APA, 26.0% (n=1401) received NOACs plus APA, 20.7% (n=1243) received warfarin without APA and 29.2% (n=1436) received warfarin plus APA. There was no significant difference in risk of recurrent stroke between the groups. Compared to receiving NOACs without APA, receiving warfarin plus APA was associated with a higher risk of mortality (hazard ratio (HR) 1.51 (95% confidence interval (CI) 1.20, 1.89)) and major bleeding (HR 1.66 (95% CI 1.40, 1.96)). Receiving NOACs plus APA was also associated with a higher risk of major bleeding compared to NOACs without APA (HR 1.27 (95% CI 1.07, 1.51), respectively).

CONCLUSIONS

The results suggest for patients with AF and carotid artery disease after ischaemic stroke, receiving NOACs without APA is associated with a lower risk of major bleeding with no negative impact on recurrent stroke or mortality. Evidence from randomised trials is needed to confirm this finding.

Patient Blood Management in Vascular Surgery

Patient blood management (PBM) is an evidence-based, multidisciplinary approach aimed at appropriately allocating blood products to patients requiring transfusion while simultaneously minimizing inappropriate transfusions. The 3 pillars of patient blood management are optimizing erythropoiesis, minimizing blood loss, and optimizing physiological reserve of anemia. Benefits seen from PBM include limiting hospital costs and mitigating harm from numerous risks of transfusion.

The safety of continuous fascia iliaca block in patients with hip fracture taking pre-injury anticoagulant and/or antiplatelet medications

BACKGROUND

Fascia iliaca compartment block (FICB) is an effective method to treat pain in adult trauma patients with hip fracture. Of importance is the high prevalence of preinjury anticoagulants and antiplatelet medications in this population. To date, we have not identified any literature that has specifically evaluated the safety of FICB with continuous catheter infusion in patients on antiplatelet and/or anticoagulant therapy. The purpose of this study is to quantify the complication rate associated with FICB in patients who are actively taking prescribed anticoagulant and/or antiplatelet medications prior to injury and identify factors that may predispose patients to an adverse event.

METHODS

This retrospective study included consecutive adult trauma patients (age ≥18) with hip fracture who underwent placement of FICB within 24 h of admission and had been taking anticoagulant and/or antiplatelet medications pre-injury. Patients were excluded if their catheter was placed more than 24 h post-hospital admission. Patients were evaluated for demographics, injury severity, laboratory values, medication history, receipt of coagulation-related reversal medications, and complications related to FICB placement. Complications included bleeding at the insertion site requiring catheter removal and 30-day catheter site infection. The incidence of complications was reported and risk factors for complications were identified using univariate and multivariate statistics.

RESULTS

There were 124 patients included. The mean age was 81 ± 10 years, and the most common mechanism was ground level fall (94%). Most patients were taking single antiplatelet therapy (65%), followed by anticoagulant alone (21%), combined antiplatelet and anticoagulant therapy (7.3%) and dual antiplatelet therapy (7.3%). The most common antiplatelet was aspirin (88%) and the most common anticoagulant was warfarin (60%). Of the patients taking warfarin, the average INR on admission was 2.3 ± 0.8. Only 1 bleeding complication (0.8%) was noted in a patient prescribed clopidogrel pre-injury which occurred 5 days post-catheter placement. This same patient was noted to have superficial surgical site bleeding most likely secondary to the use of enoxaparin for post-operative deep venous thrombosis prophylaxis. There were 4 orthopedic superficial surgical site infections (3.2%), all remote from the catheter site. The pre-injury medication prescribed in these patients was aspirin 81 mg, aspirin 325 mg, rivaroxaban and dabigatran, respectively. No factors were associated with a complication thus multivariate analysis was not performed.

CONCLUSION

The incidence of complications associated with fascia iliaca compartment block (FICB) in adult trauma patients prescribed pre-injury anticoagulants or antiplatelet medications is low. In this retrospective review, we did not identify any complications that were directly associated with the FICB procedure. Fascia iliaca block with continuous infusion catheter placement can be safely performed on patients who are on therapeutic anticoagulant and/or antiplatelet agents.

Antiplatelet Monotherapy Is Associated with an Increased Risk of Bleeding After Endoscopic Sphincterotomy

BACKGROUND

Clinical guidelines recommend continuing antiplatelet monotherapy with aspirin and, in certain situations, other antiplatelet agents in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy.

AIMS

Given the scant evidence supporting this recommendation, our primary objective was to determine if the risk of post-sphincterotomy bleeding was increased in patients on antiplatelet monotherapy.

METHODS

We performed a systematic search of Cochrane Library, Ovid Embase, Ovid Medline, Pubmed, Scopus, and Web of Science Core Collection databases. Inclusion criteria were adult patients undergoing ERCP and sphincterotomy on antiplatelet monotherapy with the comparator of no antithrombotic therapy. Our primary outcome was post-sphincterotomy bleeding. Methodological quality was assessed with the ROBINS-I tool and the Newcastle-Ottawa Scale. Meta-analysis with random-effects model was performed.

RESULTS

The search identified 4676 unique citations, with six cohort studies meeting our inclusion criteria. Post-sphincterotomy bleeding was increased in patients on antiplatelet monotherapy: OR = 1.53 (95% CI 1.03-2.28) without substantial heterogeneity (I² = 0%). The number needed to harm (the number of patients who would have to receive antiplatelet monotherapy for one additional patient to have a post-sphincterotomy bleeding episode) was 185(95% CI 80-2272). All included studies had methodological shortcomings.

CONCLUSION

Antiplatelet monotherapy was associated with a modestly increased risk of post-sphincterotomy bleeding in our systematic review and meta-analysis. More high-quality studies are needed to improve certainty regarding the estimated effect size.

REGISTRATION

PROSPERO CRD42020153019.

P2Y12 reaction units and ischemic and bleeding events after neuro-endovascular treatment

BACKGROUND AND PURPOSE

To investigate the associations of perioperative P2Y12 reaction units (PRU) measured using VerifyNow with ischemic and bleeding events, and to determine the PRU threshold in the setting of elective neuro-endovascular treatment (EVT) for intracranial/extracranial vascular disease in patients taking aspirin and clopidogrel.

METHODS

Of the patients undergoing elective neuro-EVT while taking aspirin and clopidogrel, those taking both antiplatelet agents for 7 days or more and whose PRU and aspirin reaction units (ARU) were measured were included. The primary and safety outcomes were defined as symptomatic ischemic and major bleeding events within 30 days after EVT.

RESULTS

A total of 197 patients were available for the analyses. Higher PRU was associated with symptomatic ischemic events on multivariable logistic analysis (odds ratio per 10 increase 1.14 [95% confidence interval 1.03-1.27], p=0.011). Receiver operating characteristic curve analysis showed that PRU ≥212 was the threshold to predict symptomatic ischemic events (area under the curve=0.73; sensitivity, 62.5%; specificity, 82.0%). Lower PRU was also associated with major bleeding events (odds ratio per 10 increase 0.87 [0.78-0.96], p=0.004), and the threshold to predict major bleeding events was PRU ≤46 (area under the curve=0.76; sensitivity, 70.0%; specificity, 87.2%) CONCLUSIONS: The PRU value was associated with symptomatic ischemic and major bleeding events after elective neuro-EVT in patients taking aspirin and clopidogrel. PRU ≥212 and PRU ≤46 appeared to be the threshold values to predict symptomatic ischemic and major bleeding events, respectively.

An update on drug-drug interactions associated with proton pump inhibitors

INTRODUCTION

Proton pump inhibitors (PPIs) block the gastric H/K-ATPase, therefore inhibiting acid gastric secretion, leading to an increased pH (>4). They account for an extremely high number of prescriptions worldwide. Numerous drug-drug interactions have been described with PPIs, but all the described interactions do not have clinical significance.

AREAS COVERED

This review will discuss the latest updates on drug-drug interactions with PPIs, focusing on the last ten-year publications in the following areas: anti-infective agents, anticancer drugs, antiplatelet agents and anticoagulants, and antidiabetics.

EXPERT OPINION

Although pharmacokinetic interactions of PPIs have been described with many drugs, their clinical relevance remains controversial. However, given the extremely high number of people being treated with PPIs, clinicians should remain vigilant for interactions that may be clinically significant and require dose adjustment or therapeutic monitoring. Interestingly, not all PPIs have the same pharmacokinetic and pharmacodynamic profile, with some having a strong potential to inhibit CYP2C19, such as omeprazole, esomeprazole and lansoprazole, while others, pantoprazole, rabeprazole and dexlansoprazole, are weak CYP2C19 inhibitors. These may be preferred depending on co-prescribed treatments.In addition, new formulations have been developed to prevent some of the gastric pH-dependent drug interactions and should be evaluated in further large-scale prospective comparative studies.

Impact of antiplatelet agents and anticoagulants on the performance of fecal immunochemical tests: a systematic review and meta-analysis

BACKGROUND

Antithrombotic agents may increase the bleeding tendency and affect the performance of fecal immunochemical test (FIT). We aimed to evaluate the impact of antithrombotic agents on the performance of FIT through a systematic review and meta-analysis.

METHODS

All relevant studies published between January 1980 and September 2020 that examined the diagnostic performance of FIT were searched through MEDLINE, EMBASE, and Cochrane Library databases. We performed a meta-analysis for the positive predictive value (PPV) of FIT for detecting advanced colorectal neoplasia (ACRN) or colorectal cancer (CRC) according to the administration of antithrombotic agents including aspirin, antiplatelet agents, and oral anticoagulants (OACs).

RESULTS

Thirteen studies with 27,518 patients were included. Of these, 11 studies with data required for the calculation of pooled PPV were included in the meta-analysis. The pooled PPV of FIT for detecting ACRN was significantly lower in antithrombotic agent users than in non-users (odds ratio [OR] [95% confidence interval [CI]]: aspirin, 0.82 [0.68-0.99]; antiplatelet agents, 0.82 [0.69-0.96]; OACs, 0.66 [0.52-0.84]). For detecting CRC, antithrombotic agent use tended to be associated with a reduced PPV (aspirin, 0.76 [0.51-1.14]; antiplatelet agents, 0.73 [0.52-1.02]; OACs, 0.60 [0.25-1.44]). In the subgroup analysis, a FIT cutoff value of 15 μg Hb/g feces tended to be associated with lower PPVs compared to a value of 20 μg Hb/g feces in antithrombotic agent users.

CONCLUSIONS

Aspirin, antiplatelet agents, and OACs significantly lowered the PPV of FIT for detecting ACRN. These drugs may increase the false-positive of FIT.

Antiplatelet therapy associated with lower prevalence of advanced liver fibrosis in non-alcoholic fatty liver disease: A systematic review and meta-analysis

Despite the growing disease burden of non-alcoholic fatty liver disease (NAFLD), approved medical treatments to improve or prevent liver fibrosis are effective only in a small number of patients. Recent studies have found the new use of antiplatelet agents for antifibrotic benefits in NAFLD, but human studies are still limited. The goal of this meta-analysis was to combine the findings of existing relevant studies to investigate the effects of antiplatelet therapy in reducing or preventing advanced liver fibrosis in patients with NAFLD. We conducted a systematic literature search in PubMed, EMBASE, and Web of Science databases from inception to January 2021 to identify all original studies that investigated the use of antiplatelet agents in patients with NAFLD. We used the National Institutes of Health's quality assessment tool for observational cohort and cross-sectional studies to assess study quality and risk of bias. The primary outcome was the prevalence of advanced liver fibrosis stage 3-4. Data from each study was combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate pooled odds ratio (OR) and 95% confidence intervals (CIs). Of the 2,498 studies identified, 4 studies involving 2,593 patients with NAFLD were included in this study (949 antiplatelet agent users and 1,644 non-antiplatelet agent users). The use of aspirin and/or P2Y12 receptor inhibitors was associated with a lower pooled OR of advanced liver fibrosis in patients with NAFLD (pooled OR = 0.66; 95% CI: 0.53-0.81, I² = 0.0%; p < 0.001). This study focuses on the outcome of advanced liver fibrosis in patients with NAFLD. Our study is limited by the small number of studies that were included. Preliminary evidence from this meta-analysis suggests a protective association between antiplatelet therapy and the prevalence of advanced liver fibrosis in patients with NAFLD. Our findings support future research into repositioning an antiplatelet agent as a novel NAFLD treatment.

Escalation of Antithrombotic Therapy Should Be Considered in the Presence of Intraluminal Prosthetic Graft Thrombus Following Endovascular Aneurysm Repair

Objectives

Intraluminal prosthetic graft thrombus (IPT) following Endovascular Aneurysm Repair (EVAR) can have serious consequences. The aim of this study was to assess the prevalence of IPT and to identify the risk factors for its formation and progression.

Methods

This was a retrospective study of 258 patients who had EVAR between 2015 and 2018. Demographic data, comorbidities, operative data, antithrombotic therapy, CT anatomical data, IPT characteristics (site, regression, and progression), and re-interventions were collected. Univariable analysis followed by multivariable logistic regression and Cox regression were used for data analysis.

Results

The mean age of patients was 76 years (range 55-95) and 27 (10.5 %) were females. IPT was present in 26 patients (10.1%) with a median time to occurrence of six (range 1- - 24) months. Of the group that developed IPT, six (23.1 %) developed symptoms and two (7.7%) had re-interventions. Multivariable logistic regression analysis revealed peripheral arterial disease to be associated with the formation of IPT (OR 7.4, 95% CI 1.6-35.3, p = 0.02) and escalation of antithrombotic therapy was associated with regression or prevention of progression of IPT (OR 0.1, 95% CI 0.0-0.6, p = 0.01).

Conclusion

PAD is associated with the formation of IPT after EVAR and warrants consideration of escalation of antithrombotic therapy to prevent further progression and complications.

P2Y12 inhibitor versus aspirin monotherapy for secondary prevention of cardiovascular events: meta-analysis of randomized trials

Aim

To compare the efficacy and safety of P2Y₁₂ inhibitor or aspirin monotherapy for secondary prevention in patients with atherosclerotic cardiovascular disease (ASCVD).

Methods and results

Medline, Embase, and Cochrane Central databases were searched to identify randomized trials comparing monotherapy with a P2Y₁₂ inhibitor versus aspirin for secondary prevention in patients with ASCVD (cardiovascular, cerebrovascular, or peripheral artery disease). The primary outcome was major adverse cardiac events (MACE). Secondary outcomes were myocardial infarction (MI), stroke, all-cause mortality, and major bleeding. A random-effects model was used to calculate risk ratios (RR) and the corresponding 95% confidence interval (CI) and heterogeneity among studies was assessed using the Higgins I² value. A total of 9 eligible trials (5 with clopidogrel and 4 with ticagrelor) with 61 623 patients were included in our analyses. Monotherapy with P2Y₁₂ inhibitors significantly reduced the risk of MACE by 11% (0.89, 95% CI 0.84-0.95, I² = 0%) and MI by 19% (0.81, 95% CI 0.71-0.92, I2 = 0%) compared with aspirin monotherapy. There was no significant difference in the risk of stroke (0.85, 95% CI 0.73-1.01), or all-cause mortality (1.01, 95% CI 0.92-1.11). There was also no significant difference in the risk of major bleeding with P2Y₁₂ inhibitor monotherapy compared with aspirin (0.94, 95% CI 0.72-1.22, I² = 42.6%). Results were consistent irrespective of the P2Y₁₂ inhibitor used.

Conclusion

P2Y₁₂ inhibitor monotherapy for secondary prevention is associated with a significant reduction in atherothrombotic events compared with aspirin alone without an increased risk of major bleeding.

Risk of colonoscopic post-polypectomy bleeding in patients on single antiplatelet therapy: systematic review with meta-analysis

Background

It was not yet fully established whether the use of antiplatelet agents (APAs) is associated with an increased risk of colorectal post-polypectomy bleeding (PPB). Temporarily, discontinuation of APAs could reduce the risk of PPB, but at the same time, it could increase the risk of cardiovascular disease recurrence. This study aimed to assess the PPB risk in patients using APAs compared to patients without APAs or anticoagulant therapy who had undergone colonoscopy with polypectomy.

Methods

A systematic electronic search of the literature was performed using PubMed/MEDLINE, Scopus, and CENTRAL, to assess the risk of bleeding in patients who do not interrupt single antiplatelet therapy (P2Y12 inhibitors or aspirin) and undergone colonoscopy with polypectomy.

Results

Of 2417 identified articles, 8 articles (all of them were non-randomized studies of interventions (NRSI); no randomized controlled trials (RCT) were available on this topic) were selected for the meta-analysis, including 1620 patients on antiplatelet therapy and 13,321 controls. Uninterrupted APAs single therapy was associated with an increased risk of PPB compared to the control group (OR 2.31; CI 1.37–3.91). Patients on P2Y12i single therapy had a higher risk of both immediate (OR 4.43; CI 1.40–14.00) and delayed PPB (OR 10.80; CI 4.63–25.16) compared to the control group, while patients on aspirin single therapy may have a little to no difference increase in the number of both immediate and delayed PPB events.

Conclusions

Uninterrupted single antiplatelet therapy may increase the risk of PPB, but the evidence is very uncertain. The risk may be higher in delayed PPB. However, in deciding to discontinue APAs before colonoscopy with polypectomy, the potential higher risk of major adverse cardiovascular events should always be assessed.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08975-0.

The year in cardiovascular medicine: interventional cardiology

Since last year’s report in the European Heart Journal, we have witnessed substantial progress in all aspects of interventional cardiology. Of note, the practice of interventional cardiology took place amidst successive waves of the COVID-19 pandemic, which continues to be a major burden for all healthcare professionals around the globe. In our yearly review, we shall revisit the developments in percutaneous coronary intervention (PCI), structural heart interventions, and adjunctive pharmacotherapy.

Oral anticoagulants vs antiplatelets in cryptogenic stroke with potential cardiac emboli: Meta-analysis

BACKGROUND

The best antithrombotic strategy for cryptogenic stroke with potential cardiac emboli is not known. The objective of this study was to conduct a meta-analysis to evaluate the efficacy and safety of oral anticoagulants (OACs) vs. antiplatelet therapies in these patients METHODS: Pubmed, EMBASE, CENTRAL and clinicaltrials.gov were searched from January 1980 to April 2021 to identify trials comparing OACs versus antiplatelet therapies in patients with cryptogenic stroke and potential cardiac emboli (patent foramen ovale, moderate-severe left atrial enlargement, heart failure with reduced ejection fraction). Relative risk (RR) with 95% confidence (CI) was used as a measure of the effect of OACs versus antiplatelet therapies on recurrent ischemic stroke and major bleeding. We computed a random-effect estimate based on the Mantel-Haenszel method for a given outcome.

RESULTS

We identified 6 studies derived from 5 trials with 2282 patients. Pooled results from 6 studies showed that compared with antiplatelet therapies, OACs were associated with a lower risk of recurrent ischemic stroke (RR 0.61, 95% CI 0.41 to 0.91, P=0.02). Only 3 studies of cryptogenic stroke with patent foramen ovale reported a major bleeding endpoint and pooled results from random-effects model showed that OACs compared with antiplatelet therapies were associated with a non-significantly increased risk of major bleeding (RR 1.61, 95% CI 0.76 to 3.40, P=0.21).

CONCLUSIONS

OACs compared with antiplatelet therapies were associated with a reduced recurrent ischemic stroke risk and OACs might be a viable non-procedural alternative in patients with cryptogenic stroke and potential cardiac emboli.

Profiling oxylipins released from human platelets activated through the GPVI collagen receptor

In addition to haemostasis, platelets are involved in pathological processes, often driven by material released upon activation. Interaction between collagen and glycoprotein VI (GPVI) is a primary platelet stimulus that liberates arachidonic acid and linoleic acid from membrane phospholipids. These are oxidised by cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) to eicosanoids and other oxylipins with various biological properties. Using liquid chromatography-tandem mass spectrometry we found that GPVI-stimulated platelets released significant levels of ten oxylipins; the well documented TxA2 and 12-HETE, PGD₂ and PGE_2, as well as 8-, 9-, 11-, and 15-HETE, 9- and 13-HODE.¹ Levels of oxylipins released from washed platelets mirrored those from platelets stimulated in the presence of plasma, indicating generation from intracellular, rather than exogenous AA/LA. Inhibition of COX-1 with aspirin, as expected, completely abolished production of TxA₂ and PGD/E₂, but also significantly inhibited the release of 11-HETE (89 ± 3%) and 9-HODE (74 ± 6%), and reduced 15-HETE and 13-HODE by ∼33 %. Inhibition of 12-LOX by either esculetin or ML355 inhibited the release of all oxylipins apart from 15-HETE. These findings suggest routes to modify the production of bioactive molecules released by activated platelets.

Additional Effects of Antiplatelet Therapy on Anticoagulant Agents in Patients With Bioprosthetic Valves and Atrial Fibrillation

BACKGROUND

The additional effects of single-antiplatelet therapy (SAPT) on anticoagulant therapy are still unclear in patients with atrial fibrillation (AF) after bioprosthetic valve replacement.Methods and Results:We conducted a subanalysis of a multicenter, retrospective, observational registry of patients with bioprosthetic valves and AF in Japan. Patients administered anticoagulants alone comprised the ACA group (n=107), and patients given concomitant SAPT and anticoagulant therapy comprised the On SAPT group (n=82). The primary efficacy endpoint was the incidence of stroke/systemic embolism, and the primary safety endpoint was the incidence of major bleeding. The observation period was 46.3±24.6 months. The primary efficacy endpoint occurred in 12 patients, and the cumulative incidence of primary efficacy events was significantly higher in the ACA group compared with the On SAPT group (P=0.039). The primary safety endpoint occurred in 22 patients, and the cumulative incidence of primary safety events was similar between groups (P=0.66). No differences between the groups were observed for cardiac events.

CONCLUSIONS

Additional SAPT on anticoagulant therapy in patients with bioprosthetic valves and AF was associated with a reduction in stroke/systemic embolic events, although the cumulative incidence of bleeding was similar, regardless of additional SAPT. These findings suggest that additional SAPT on anticoagulant therapy may be safe and effective in real-world clinical settings.

Management of bone marrow biopsy related bleeding risks: a retrospective observational study

Bone marrow biopsies are largely used for the diagnosis and prognostic of various hematological diseases. Complications are rare but can be as serious as hemorrhage. However, little is known about management of patients deemed at high hemorrhagic risk like thrombocytopenic patients or patients receiving antithrombotic drugs. The aim of the study was to describe the management of patients regarding their laboratory profile and antithrombotic treatment prior to bone marrow biopsy and the short-term outcomes, notably hemorrhage. We conducted a retrospective observational study between February 2007 and March 2018. A standardized form was used to collect data from patients' records, blood tests results, management of antiplatelet and anticoagulant treatment before biopsy and complications including bleeding and thromboembolic events until 3 months after the biopsy. A total of 524 bone marrow biopsies were performed. No major bleeding events were reported. The incidence of clinically relevant non-major bleeding was 0.19% (CI 95% 0.00-1.20) and was linked to low platelets counts (p = 0.002) and not to abnormal coagulation profile or antithrombotic therapy, whether or not a bridging therapy has been used. Anticoagulants were temporarily stopped before biopsy in most cases without subsequent thrombotic complications. Our data suggest that thrombocytopenic patients have a non-negligible bleeding risk. Coagulation profiling seems irrelevant. We propose an algorithm to assist the management of those patients, notably when receiving antithrombotic drugs.

Exploring the antiplatelet activity of serotonin 5-HT2A receptor antagonists bearing 6-fluorobenzo[d]isoxazol-3-yl)propyl) motif- as potential therapeutic agents in the prevention of cardiovascular diseases

Small drug-like molecules that can block the function of serotonin 5-HT_2A receptors have garnered considerable attention due to their ability to inhibit platelet aggregation and the possible prevention of atherosclerotic lesions. Although clinical data provided compelling evidence for the efficacy of this approach in the prevention of various cardiovascular conditions, the chemical space of 5-HT_2A receptor antagonists is limited to ketanserin and sarpogrelate. To expand the portfolio of novel chemical motifs with potential antiplatelet activity, we evaluated the antiplatelet activity of a series of 6-fluorobenzo[d]isoxazole derivatives that possess a high affinity for 5-HT_2A receptor. Here we describe in vitro studies showing that 6-fluorobenzo[d]isoxazole derivatives exert promising antiplatelet activity in three various in vitro models of platelet aggregation, as well as limit serotonin-induced vasoconstriction. Compound AZ928 showed in vitro activity greater than the clinically approved drug sarpogrelate. In addition to promising antiplatelet activity, the novel series was characterized by a favorable safety profile. Our findings show that the novel series exerts promising antiplatelet efficacy while being deprived of potential side effects, such as hemolytic activity, which render these compounds as potential substances for further investigation in the field of cardiovascular research.

Influence of Perioperative Antithrombic Agent Discontinuation in Elective Posterior Spinal Surgery: A Propensity-Score-Matched Analysis

OBJECTIVE

To investigate the influence of perioperative antithrombotic agent (antiplatelet agents and anticoagulants) discontinuation in elective posterior spinal surgery in terms of bleeding complications, such as epidural hematoma and postoperative thromboembolism.

METHODS

We enrolled patients undergoing elective posterior spinal surgery at 9 hospitals between April 2017 and August 2020. We collected data regarding patient baseline characteristics, surgical details, intraoperative estimated blood loss, and postoperative complication rates, including epidural hematoma and thromboembolism. We divided the patients into a discontinuation group, in which antithrombic agents were discontinued perioperatively, and a control group without antithrombic agents. Propensity scores for taking any antithrombic agents were calculated, with 1-to-1 matching based on the estimated propensity scores to adjust for patient baseline characteristics and surgical details. Intraoperative estimated blood loss and 30-day postoperative complication rates were compared between the groups.

RESULTS

We enrolled 9853 patients, including 1123 patients (11.4%) who discontinued antithrombic agents perioperatively. One-to-one propensity score matching yielded 1111 pairs with and without antithrombic agents. Intraoperative estimated blood loss per 10 minutes (8.2 mL vs. 8.9 mL) and the incidence of epidural hematoma requiring revision (0.97% vs. 0.72%) were similar between the groups. Although postoperative cardiac events and stroke were observed only in the discontinuation group (0.27% and 0.09%, respectively), these incidences were not significantly different between the groups.

CONCLUSIONS

Perioperative antithrombic agent discontinuation in elective posterior spinal surgery normalized the intraoperative bleeding tendency and the incidence of postoperative epidural hematoma and did not influence in a significative way the incidence of postoperative thromboembolism.

[Perioperative management of platelet function and anticoagulation in geriatric patients]

Geriatric patients often have cardiovascular diseases that require differentiated perioperative management of hemostasis. The operation-related bleeding risk and the individual thromboembolism risk mutually influence each other, so that a differentiated preoperative assessment of the further prescription of coagulation-modulating medication is required. In many cases the active coagulation medication can be interrupted without replacement or continued unchanged. In cardiovascular diseases with antiplatelet medication, the preoperative risk-benefit assessment for most operations leads to the continuation of previous platelet aggregation inhibitor monotherapy; however, if there is a high risk of cardiovascular thromboembolism with dual platelet inhibition, the individual perioperative medication should be closely coordinated with a geriatrician or cardiologist.In most cases, the intake of vitamin K antagonists (VKA) can be preoperatively interrupted. In cases of high risk of thromboembolism, a temporary bridging with heparin must be carried out. The introduction of the four new direct oral antagonists (DOAC) has made the perioperative management of anticoagulation much easier. Bridging with heparin is not necessary. Perioperatively, only the dosage and timing of interruption of the DOACs have to be determined individually depending on the operative bleeding risk as well as the age, body weight and kidney function of the patient. If bleeding complications arise under the influence of the DOACs, antidotes are available for three of the four DOACs, which in acute cases can be used in addition to prothrombin complex concentrates and fresh frozen plasma to normalize coagulation.

Synthesis and evaluation of novel and potent protease activated receptor 4 (PAR4) antagonists based on a quinazolin-4(3H)-one scaffold

Protease activated receptor 4 (PAR4) is an important target in antiplatelet therapy to reduce the risk of heart attack and thrombotic complications in stroke. PAR4 antagonists can prevent harmful and stable thrombus growth, while retaining initial thrombus formation, by acting on the late diffusion stage of platelet aggregation, and may provide a safer alternative to other antiplatelet agents. To date, only two PAR4 antagonists, BMS-986120 and BMS-986141 have entered clinical trials for thrombosis. Thus, the development of a potent and selective PAR4 antagonist with a novel chemotype is highly desirable. In this study, we explored the activity of quinazolin-4(3H)-one-based PAR4 antagonists, beginning with their IDT analogues. By repeated structural optimisation, we developed a series of highly selective PAR4 antagonists with nanomolar potency on human platelets. Of these, 13 and 30g, with an 8-benzo[d]thiazol-2-yl-substituted quinazolin-4(3H)-one structure, showed optimal activity (h. PAR4-AP PRP IC₅₀ = 19.6 nM and 6.59 nM, respectively) on human platelets. Furthermore, 13 and 30g showed excellent selectivity for PAR4 versus PAR1 and other receptors (IC₅₀s > 10 μM) on human platelets. And 13 and 30g were lack of cross-reactivity for PAR1 or PAR2 (PAR1 AP FLIPR IC₅₀ > 3162 nM, PAR2 AP FLIPR IC₅₀ > 1000 nM) in the calcium mobilization assays. Metabolic stability assays and cytotoxicity tests of 13 and 30g indicated that these compounds could sever as promising drug candidates for the development of novel PAR4 antagonists. In summary, the quinazolin-4(3H)-one-based analogues are the first reported chemotypes with excellent activity and selectivity against PAR4, and, in the current study, we expanded the structural diversity of PAR4 antagonists. The two compounds, 13 and 30g, found in our study could be promising starting points with great potential for further research in antiplatelet therapy.

Risk Factors for Severe Bleeding Complications in Vitreoretinal Surgery and the Role of Antiplatelet or Anticoagulant Agents

PURPOSE

To evaluate the influences and risk factors for severe bleeding complications during vitreoretinal surgery and to investigate the role of antiplatelet and anticoagulant agents.

DESIGN

Prospective trial.

PARTICIPANTS

Patients undergoing vitreoretinal surgery.

METHODS

The procedures included were pars plana vitrectomy and scleral buckling. We developed a uniform classification to grade the bleeding severity. Bleeding was graded on an ordinal scale ranging from 0 to 5. Immediately after surgery and 1 day later, the incidence and the severity of bleeding events was documented on a standardized form. A grade of 3 or more was defined as severe bleeding. Furthermore, the influence of known systemic disorders before surgery, the type of anesthesia, type of surgical procedure, intraoperative blood pressure, and the use or change of antiplatelet or anticoagulant agents on intraoperative bleeding was analyzed.

MAIN OUTCOME MEASURES

Incidence and risk factors for severe intraoperative bleeding events.

RESULTS

Data from 374 eyes undergoing vitreoretinal procedures were included in our study (mean age, 67.6 ± 12.9 years). A severe intraoperative bleeding event was observed in 15 eyes (4%). We found that concomitant diseases such as diabetes mellitus and carotid artery stenosis, the presence of diabetic retinopathy, younger age, and scleral buckling combined with a transscleral puncture were associated significantly with severe bleeding events. By contrast, use of antiplatelet or anticoagulant agents, or both, had no significant influence on severe intraoperative bleeding events.

CONCLUSIONS

Although external manipulations during buckling surgery (e.g., drainage of subretinal fluid) and concomitant diseases such as diabetes mellitus and carotid artery stenosis influences the risk of severe intraoperative bleeding events, we did not detect an increased risk related to coexisting antiplatelet or anticoagulant medication use, or both.

Sex-related disparities in the incidence and outcomes of hemorrhagic stroke among type 2 diabetes patients: a propensity score matching analysis using the Spanish National Hospital Discharge Database for the period 2016-18

Background

To analyze incidence, use of therapeutic procedures, use of oral anticoagulants (OACs) and antiplatelet agents prior to hospitalization, and in-hospital outcomes among patients who were hospitalized with hemorrhagic stroke (HS) according to the presence of type 2 diabetes mellitus (T2DM) in Spain (2016–2018) and to assess the role of sex differences among those with T2DM.

Methods

Using the Spanish National Hospital Discharge Database we estimated the incidence of HS hospitalizations in men and women aged ≥ 35 years with and without T2DM. Propensity score matching (PSM) was used to compare population subgroups according to sex and the presence of T2DM.

Results

HS was coded in 31,425 men and 24,975 women, of whom 11,915 (21.12%) had T2DM. The adjusted incidence of HS was significantly higher in patients with T2DM (both sexes) than in non-T2DM individuals (IRR 1.15; 95% CI 1.12–1.17). The incidence of HS was higher in men with T2DM than in T2DM women (adjusted IRR 1.60; 95% CI 1.57–1.63). After PSM, men and women with T2DM have significantly less frequently received decompressive craniectomy than those without T2DM. In-hospital mortality (IHM) was higher among T2DM women than matched non-T2DM women (32.89% vs 30.83%; p = 0.037), with no differences among men. Decompressive craniectomy was significantly more common in men than in matched women with T2DM (5.81% vs. 3.33%; p < 0.001). IHM was higher among T2DM women than T2DM men (32.89% vs. 28.28%; p < 0.001). After adjusting for confounders with multivariable logistic regression, women with T2DM had a 18% higher mortality risk than T2DM men (OR 1.18; 95% CI 1.07–1.29). Use of OACs and antiplatelet agents prior to hospitalization were associated to higher IHM in men and women with and without T2DM.

Conclusions

T2DM is associated with a higher incidence of HS and with less frequent use of decompressive craniectomy in both sexes, but with higher IHM only among women. Sex differences were detected in T2DM patients who had experienced HS, with higher incidence rates, more frequent decompressive craniectomy, and lower IHM in men than in women.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01334-2.

Does the discontinuation time of antiplatelet or anticoagulation treatment affect hemorrhagic complications in patients undergoing craniotomy for neurovascular lesions?

BACKGROUND

The number of patients treated with platelet inhibitors (PI) and/or anticoagulants (AC) in neurosurgery is increasing. The aim of this study was to analyse the effect of PI/AC discontinuation time on hemorrhagic events after craniotomy for neurovascular pathologies.

METHODS

The 30-day postoperative bleeding rates were retrospectively compared between short (≤5 days) and long (>5 days) discontinuation time of PI/AC before and after surgery. Kaplan-Meier survival analysis comparing time to postoperative bleeding and the effect of PI/AC discontinuation time on bleeding rates were analysed. Potential risk factors for postoperative bleeding were further analysed in uni- and multivariate analysis.

RESULTS

Out of 215 consecutive patients undergoing craniotomy for neurovascular lesions between January 2009 and April 2019, 23.3% were treated with PI/AC. Of these 36% (n = 18) and 20.8% (n = 10) were included in the short pre- and postoperative discontinuation group, respectively. Bleeding rates were comparable between the pre- and postoperative short and long discontinuation groups (preoperative 11.1% vs 10%, p = .659; postoperative 0% vs 13.2%, p = .566). In-hospital mortality rates and time to bleed of the groups were comparable as well. Similarly, the rate for thromboembolic events was not significantly affected by the pre- or postoperative discontinuation time of PI/AC. After multivariate analysis preoperative bleeding of the lesion was significantly associated with postoperative bleeding.

CONCLUSIONS

Patients with short discontinuation time of PI/AC treatment undergoing craniotomy for the treatment of neurovascular lesions do not appear to have increased rates of postoperative bleeding.

Antiplatelet regimens for Asian patients with ischemic stroke or transient ischemic attack: a systematic review and network meta-analysis

Background

The optimal antiplatelet treatment for the secondary prevention of non-cardioembolic stroke or transient ischemic attack (TIA) remains uncertain in Asians.

Methods

We searched for eligible randomized control trials in Medline, Embase, and the Cochrane Library. A Bayesian network meta-analysis (NMA) was performed to assess the efficacy and safety of antiplatelet regimens with placebo as the control. Each therapy was compared using relative risk ratios (RR) and 95% credible intervals (CrI), and ranked according to the value of the surface under the cumulative ranking curve.

Results

A total of 84,103 patients from 32 studies were included: patients in used aspirin (n=26,834); cilostazol (n=3,303); clopidogrel (n=12,406); prasugrel (n=1,885); sarpogrelate (n=752); ticagrelor (n=1,933); ticlopidine (n=1,644); triflusal (n=391); aspirin plus cilostazol (n=1,120), aspirin plus clopidogrel (n=4,623); aspirin plus dipyridamole (n=10,853); aspirin plus ticagrelor (n=5,859); aspirin plus ticlopidine (n=132). Patients who used aspirin plus clopidogrel and cilostazol had a lower risk of recurrent stroke than those who used placebo. Patients administered with aspirin plus ticagrelor, aspirin plus clopidogrel, and cilostazol had a lower risk of composite vascular events than those administered placebo. Patients administered aspirin plus ticagrelor had a higher risk of major bleeding than those administered placebo. Clustered three-dimensional rank plots of recurrent stroke, major bleeding, and composite vascular events demonstrated that cilostazol had higher values of the surface under the cumulative ranking curve than other treatments.

Conclusions

Of the antiplatelet regimens, cilostazol showed the best net clinical benefits than other antiplatelet regimens in Asians with non-cardioembolic stroke or TIA.

Monosubstituted Coumarins Inhibit Epinephrine-Induced Platelet Aggregation Antiplatelet Effect of Monosubstituted Coumarins

Aim

The aim of this study was to evaluate the in vitro effect of coumarin and 15 monosubstituted  derivatives on  the inhibition  of human platelet  aggregation  induced by various  pro-aggregatory agonists, particularly by epinephrine.

Background

The emergence of residual platelet reactivity during the use of conventional antiplatelet agents (acetylsalicylic acid and clopidogrel) is one of the main causes of double therapy´s therapeutic failure. Platelet adrenoceptors participate in residual platelet reactivity. Therefore, it is necessary to develop new antiplatelet agents that inhibit epinephrine-induced platelet aggregation as a new therapeutic strategy. Information on the antiplatelet activity of coumarins in inhibiting epinephrine-induced aggregation is limited.

Objective

The objective of this study was to establish the structure-activity relationship (SAR) of coumarin derivatives with hydroxy, methoxy, and acetoxy groups in different positions of the coumarin nucleus to identify the most active molecules. Moreover, this study aimed to use in silico studies to suggest potential drug targets to which the molecules bind to produce antiplatelet effects.

Methods

The platelet aggregation was performed using a Lumi-aggregometer; the inhibitory activity of 16 compounds were evaluated by inducing the aggregation of human platelets (250 × 10³/μl) with epinephrine (10 µM), collagen (2 µg/ml) or ADP (10 µM). The aggregation of control platelets was considered 100% of the response for each pro-aggregatory agonist.

Results

Eleven molecules inhibited epinephrine-induced aggregation, with 3-acetoxycoumarin and 7-methoxycoumarin being the most active. Only coumarin inhibited collagen-induced platelet aggregation, but no molecule showed activity when using ADP as an inducer.

Conclusions

In silico studies suggest that most active molecules might have antagonistic interactions in the α₂ and β₂ adrenoceptors. The antiplatelet actions of these coumarins have the potential to reduce residual platelet reactivity and thus contribute to the development of future treatments for patients who do not respond adequately to conventional agents.

Evaluation of serious bleeding signals during concomitant use of clopidogrel and hypnotic drugs

BACKGROUND

In a previous drug-drug interaction (DDI) screening study intended to generate hypotheses, clopidogrel + either eszopiclone or zolpidem (vs. clopidogrel alone) were associated with serious bleeding.

OBJECTIVES

To confirm or refute these DDI signals and examine associations with other hypnotics in an independent population of United States Medicaid beneficiaries METHODS: We employed a bi-directional self-controlled case series design in eligible individuals concomitantly exposed to one of 12 hypnotics (precipitants, exposures of interest) plus either clopidogrel (the object drug) or pravastatin (the negative control object drug). The outcome was hospital presentation with serious bleeding. Using conditional Poisson regression, we calculated confounder-adjusted rate ratios (RRs) and 95% confidence intervals for serious bleeding during clopidogrel + precipitant use (vs. clopidogrel alone). To distinguish a DDI from a precipitant's inherent effect on bleeding, we divided effect measures by the adjusted RR for the corresponding pravastatin + precipitant pair to obtain ratios of RR (RRRs).

RESULTS

Among 23,194 users of clopidogrel and 3824 of pravastatin who experienced serious bleeding during an active prescription for one of these agents, confounder-adjusted RRRs for serious bleeding were 6.63 (0.39-113.01) and 0.77 (0.53-1.11) with eszopiclone and zolpidem, respectively, whereas confounder-adjusted RRRs for other hypnotics ranged from 0.18 (0.04-0.85) for triazolam to 1.79 (0.16-20.44) for zaleplon. Statistical imprecision therefore precluded us from confirming or refuting these prior signals with eszopiclone and zolpidem.

CONCLUSIONS

While we could not confirm or refute previously identified DDI signals, numerically elevated RRRs for serious bleeding with several clopidogrel + hypnotic pairs warrant further examination.

Antiplatelet therapy in patients with Covid-19: A retrospective observational study

Introduction

Covid-19 is associated with a high risk of venous thromboembolism. In addition, cases of arterial thromboembolism were also reported. We investigated the effect of antiplatelet therapy on the disease course.

Methods

We evaluated a cohort of inpatients with Covid-19 (n ​= ​152). We recorded the patient's demographic data, their comorbidities, medication use including the use of antiplatelets and anticoagulants, laboratory findings and data about mechanical ventilation. We then separated the patient's outcomes into either being "bad" (dead or referral to higher level of care) or "good" (discharged). Then we evaluated the factors that contributed to the patient needing ventilatory support and to showing typical radiological findings.

Results

In our cohort, 21 patients received ventilatory support whereas 131 did not require the use of ventilators. 127 patients had good outcomes and 25 had bad outcomes. By using multivariate analysis, we found that the need for ventilatory support was the strongest predictor of a bad outcome. All patients who were on ventilators displayed typical radiological findings. The factors predicting the need for ventilatory support were LDH and CRP levels, the presence of cardiac conduction abnormalities as well as chronic lung conditions. Cardiac conduction abnormalities, LDH and CRP levels, and the use of antiplatelets, were factors that predicted typical radiological findings.

Conclusions

There was a higher incidence of typical radiological findings in patients on antiplatelet medication. However, it did not translate into changes in the ventilation requirement or in the outcome. The need for mechanical ventilation was the strongest predictor of a bad outcome.

Outcomes of Endoscopic Ultrasound-Guided Biliary Drainage in Patients Undergoing Antithrombotic Therapy

BACKGROUND/AIMS

The Japan Gastroenterological Endoscopy Society (JGES) has published guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment. These guidelines classify endoscopic ultrasound-guided biliary drainage (EUS-BD) as a high-risk procedure. Nevertheless, the bleeding risk of EUS-BD in patients undergoing antithrombotic therapy is uncertain. Therefore, this study aimed to assess the bleeding risk in patients undergoing antithrombotic therapy.

METHODS

This single-center retrospective study included 220 consecutive patients who underwent EUS-BD between January 2013 and December 2018. We managed the withdrawal and continuation of antithrombotic agents according to the JGES guidelines. We compared the bleeding event rates among patients who received and those who did not receive antithrombotic agents.

RESULTS

A total of 18 patients (8.1%) received antithrombotic agents and 202 patients (91.8%) did not. Three patients experienced bleeding events, with an overall bleeding event rate of 1.3% (3/220): one patient was in the antithrombotic group (5.5%) and two patients were in the non-antithrombotic group (0.9%) (p=0.10). All cases were moderate. The sole thromboembolic event (0.4%) was a cerebral infarction in a patient in the non-antithrombotic group.

CONCLUSION

The rate of EUS-BD-related bleeding events was low. Even in patients receiving antithrombotic therapy, the bleeding event rates were not significantly different from those in patients not receiving antithrombotic therapy.

[Clinical Practice Guideline for the Management of Antithrombotic Agents in Patients Undergoing Gastrointestinal Endoscopy]

Antithrombotic agents, including antiplatelet agents and anticoagulants, are increasingly used in South Korea. The management of patients using antithrombotic agents and requiring gastrointestinal endoscopy is an important clinical challenge. Although clinical practice guidelines (CPGs) for the management of patients receiving antithrombotic agents and undergoing gastrointestinal endoscopy have been developed in the Unites States, Europe, and Asia Pacific region, it is uncertain whether these guidelines can be adopted in South Korea. After reviewing current CPGs, we identified unmet needs and recognized significant discrepancies in the clinical practice among regions. This is the first CPG in Korea providing information that may assist endoscopists in the management of patients on antithrombotic agents who require diagnostic or elective therapeutic endoscopy. This guideline was developed through the adaptation process as an evidence-based method, with four guidelines retrieved by systematic review. Eligible guidelines were evaluated according to the Appraisal of Guidelines for Research and Evaluation II process, and 13 statements were established using a grading system. This guideline was reviewed by external experts before an official. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

Synthesis of ticagrelor analogues belonging to 1,2,3-triazolo[4,5-d]pyrimidines and study of their antiplatelet and antibacterial activity

Based on the recent observation that the antiplatelet agent ticagrelor and one of its metabolite exert bactericidal activity against gram-positive bacteria, a series of 1,2,3-triazolo[4,5-d]pyrimidines structurally related to ticagrelor were synthesized and examined as putative antiplatelet and antibacterial agents. The aim was to assess the possibility of dissociating the two biological properties and to find novel 1,2,3-triazolo[4,5-d]pyrimidines expressing antiplatelet activity and devoid of in vitro antibacterial activity. The new compounds synthesized were known metabolites of ticagrelor as well as structurally simplified analogues. Some of them were found to express antiplatelet activity and to lose the antibacterial activity, supporting the view that the two activities were not necessarily linked.

Clinical Practice Guideline for the Management of Antithrombotic Agents in Patients Undergoing Gastrointestinal Endoscopy

Antithrombotic agents, including antiplatelet agents and anticoagulants, are increasingly used in South Korea. The management of patients using antithrombotic agents and requiring gastrointestinal endoscopy is an important clinical challenge. Although clinical practice guidelines (CPGs) for the management of patients receiving antithrombotic agents and undergoing gastrointestinal endoscopy have been developed in the Unites States, Europe, and Asia Pacific region, it is uncertain whether these guidelines can be adopted in South Korea. After reviewing current CPGs, we identified unmet needs and recognized significant discrepancies in the clinical practice among regions. This is the first CPG in Korea providing information that may assist endoscopists in the management of patients on antithrombotic agents who require diagnostic or elective therapeutic endoscopy. This guideline was developed through the adaptation process as an evidence-based method, with four guidelines retrieved by systematic review. Eligible guidelines were evaluated according to the Appraisal of Guidelines for Research and Evaluation II process, and 13 statements were established using a grading system. This guideline was reviewed by external experts before an official. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.

Current strategies to minimize postoperative hematoma formation in patients undergoing cardiac implantable electronic device implantation: A review

There are an increasing number of cardiac electronic device implants and generator changes with a longer patient life expectancy along with concomitant increase in antiplatelet and anticoagulant regimens, which can increase the incidence of pocket hematomas. We have conducted an in-depth analysis on the relevant literature, which is rife with varying definition of hematomas, on ways to reduce pocket hematomas. We have analyzed studies on periprocedural medication management, intraprocedural use of prohemostatic agents, and postprocedure role of compression devices.

Risk of postprocedural intracerebral hemorrhage in patients with ruptured cerebral aneurysms after treatment with antiplatelet agents

OBJECTIVE

Endovascular treatment of ruptured cerebral aneurysms frequently requires antiplatelet medication to prevent thromboembolism. This might raise concern regarding the risk of postprocedural hemorrhage (pH), e.g. from placement of intracranial probes. We explored the risk of PH associated with standard antiplatelet therapy (sAP: acetylsalicylic acid, and/or clopidogrel) in the context of aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

We retrospectively reviewed a total of 146 consecutive cases with cerebral aneurysms treated between 1/2011-12/2015, and distinguished between minor (0.5 cm³) - 4 cm³) or major (> 4 cm³) PH occurring within four weeks after intervention. A separate analysis included hemorrhages related to placement of intracranial probes and drainages in the subgroup of 99 cases with such surgical interventions (pPH). Clinical outcome was assessed via Glasgow Outcome Scale (GOS) twelve months after aSAH.

RESULTS

A total of 49 cases (33.6%) in the overall sample sustained PH, there were 19 cases of pPH. Multifactorial analyses yielded sAP as an independent predictor for minor, but not major PH (p < 0.001 vs. p = 0.829), with comparable results for pPH (p = 0.001 vs. p = 0.184). sAP did not influence the clinical outcome in either group.

CONCLUSIONS

sAP was associated with a higher rate of minor PH and, more specifically, of minor pPH. However, it was neither accompanied by the occurrence of major hemorrhages nor by unfavorable clinical outcome. Future prospective studies should confirm these observations and hemorrhage risks associated with extended anticoagulation regimes after complex interventions and intra-arterial vasospasm therapy should be explored in order to facilitate interdisciplinary decision-making in aSAH.

An attempt to chemically state the cross-talk between monomers of COX homodimers by double/hybrid inhibitors mofezolac-spacer-mofezolac and mofezolac-spacer-arachidonic acid

Cardiovascular diseases (CVDs) account for over 17 million death globally each year, including arterial thrombosis. Platelets are key components in the pathogenesis of this disease and modulating their activity is an effective strategy to treat such thrombotic events. Cyclooxygenase-1 (COX-1) isoenzyme is involved in platelet activation and is the main target of non-steroidal anti-inflammatory drugs (NSAIDs) and new selective inhibitor research. Inhibitors of general formula mofezolac-spacer-mofezolac (mof-spacer-mof) and mofezolac-spacer-arachidonic acid (mof-spacer-AA) were projected to investigate the possible cross-talk between the two monomers (E_allo and E_cat) forming the COX-1 homodimer. Mofezolac was chosen as either one or two moieties of these molecules being the known most potent and selective COX-1 inhibitor and administrated to humans as Disopain™, then arachidonic acid (AA) was used to develop molecules bearing, in the same compound, in addition to the inhibitor moiety (mofezolac) also the natural COX substrate. Depending on the nature of the spacer, COX-1 and COX-2 activity was differently inhibited by mof-spacer-mof set with a preferential COX-1 inhibition. The highest COX-1 selectivity was exhibited by the compound in which the spacer was the benzidine [N,N'-(biphenyl-4,4'-di-yl)bis (2-[3,4-bis(4-methoxyphenyl)isoxazol-5-yl]acetamide) (15): COX-1 IC₅₀ = 0.08 μM, COX-2 IC₅₀ > 50 μM, Selectivity Index (SI) > 625]. In the case of mof-spacer-AA set, the COX inhibitory potency and also the isoform preference changed. (5Z, 8Z, 11Z, 14Z)-N-(4-{2-[3,4-Bis(4-methoxyphenyl)isoxazol-5-yl]acetamido}butyl)icosa-5,8,11,14-tetraenamide (19) and (5Z, 8Z, 11Z, 14Z)-N-(4'-{2-[3,4-bis(4-methoxyphenyl)isoxazol-5-yl]acetamido}-[1,1'-biphenyl]-4-yl)icosa-5,8,11,14-tetraenamide (21), in which the spacer is the 1,2-diaminobutane or benzidine, respectively, selectively inhibited the COX-2, whereas when the spacer is the 1,4-phenylendiamine [(5Z, 8Z, 11Z, 14Z)-N-(4-{2-[3,4-bis(4-methoxyphenyl)isoxazol-5-yl]acetamido}phenyl)icosa-5,8,11,14-tetraenamide) (20) the COX preference is COX-1 (COX-1 IC₅₀ = 0.05 μM, COX-2 IC₅₀ > 50 μM, with a COX-1 selectivity > 1000). Molecular modelling by using FLAP algorithm shows fundamental interactions of the novel compounds at the entry channel of COX and inside its catalytic cavity. The effect of these mof-spacer-mof and mof-spacer-AA in inhibiting in vitro free arachidonic acid-induced platelet aggregation was also determined. A positive profile of hemocompatibility in relation to their influence on the blood coagulation cascade and erythrocyte toxicity was observed. Cytotoxicity and genotoxicity safety were also found for these two novel sets of compounds.

Antithrombotic Agent Use in Elderly Patients Sustaining Low-Level Falls

BACKGROUND

Elderly patients who are injured from a low-level fall comprise an increasing percentage of trauma admissions. We sought to evaluate the prevalence of antithrombotic (anticoagulant or antiplatelet) agent use, injury patterns, and outcomes in this population, focusing on intracranial hemorrhage (ICH).

METHODS

We retrospectively reviewed the trauma registry at an American College of Surgeons-verified Level I trauma center for all patients aged 65 y or older admitted between 2007 and 2016 following a low-level fall. Medical records of patients on antithrombotic agents were examined in detail. Patients were divided into four groups based on the presence/absence of ICH and presence/absence of preadmission antithrombotic medication use.

RESULTS

There were 4074 elderly patients admitted after a low-level fall, of which 1153 (28.3%) had a traumatic ICH, and 1238 (30.4%) were on antithrombotic agents. Notably, 35.9% of patients on antithrombotics had an ICH, as compared to 25.0% of 2836 patients not on antithrombotics other than aspirin (P < 0.001). The overall distribution of antithrombotic agent use differed significantly between the ICH and non-ICH groups; the ICH group had more coumadin usage. The mortality rate was significantly different across groups, with the group having ICH and a history of antithrombotics having the highest mortality at 14.2% (P < 0.001). Excluding the 27.8% of patients who were transferred into our hospital demonstrated that significantly more admissions on antithrombotics had ICH (22.4%) versus ICH admissions not on antithrombotics (14.7%, P < 0.001). The mortality rate was significantly different across groups, with the group having ICH and a history of antithrombotics having the highest mortality at 12.0% (P < 0.001). On multivariable analysis, anticoagulants, antiplatelets, and aspirin were all significantly associated with ICH; but only anticoagulants were significantly associated with mortality.

CONCLUSIONS

Antithrombotic agent use was common in admitted elderly patients sustaining a low-level fall and is associated with an elevated rate of ICH. Anticoagulants were also associated with increased mortality.

Protease activated receptor 4 (PAR4) antagonists: Research progress on small molecules in the field of antiplatelet agents

Protease activated receptor 4 (PAR4) is a key target in antiplatelet medication to reduce the risk of heart attack and thrombotic complications in stroke. PAR4 antagonists can prevent harmful and stable thrombus growth while retaining initial thrombus formation by acting on the late diffusion stage of platelet activation, which may provide a safer alternative than other antiplatelet agents. Currently, research on PAR4 antagonists is of increasing interest in the field of antiplatelet agents. This article provides an overview of the discovery and development of small-molecule antagonists of PAR4 as novel antiplatelet agents, including structure-activity relationship (SAR) analysis, progress of structure and bioassay optimization, and the latest structural and/or clinical information of representative small-molecule antagonists of PAR4.

Pharmacological characterization of the biosynthesis of prostanoids and hydroxyeicosatetraenoic acids in human whole blood and platelets by targeted chiral lipidomics analysis

Platelet 12-lipoxygenase(p-12-LOX) is highly expressed in human platelets, and the development of p-12-LOX inhibitors has the potential to be a novel antithrombotic tool by inhibiting thrombosis without prolonging hemostasis. A chiral liquid chromatography-mass spectrometry(LC-MS/MS) method was used to assess the impact of three commercially available LOX inhibitors[esculetin(6,7-dihydroxycoumarin), ML-355(N-2-benzothiazolyl-4-[[(2-hydroxy-3-methoxyphenyl)methyl]amino]-benzenesulfonamide), CDC(cinnamyl-3,4-dihydroxy-α-cyanocinnamate) and acetylsalicylic acid(ASA; a cyclooxygenase-1 inhibitor) on the generation of prostanoids and HETEs(hydroxyeicosatetraenoic acids) in human whole blood allowed to clot for 1 h at 37 °C(serum), platelet-rich plasma(PRP) stimulated with collagen or TRAP-6(a peptide activating thrombin receptor) and washed platelets. In serum, ML-355 did not affect eicosanoid generation, while CDC caused an incomplete reduction of 12S-HETE levels; esculetin inhibited both 12S-HETE and thromboxane(TX)B₂ production; ASA selectively affected TXB₂ production. In washed platelets stimulated with thrombin, esculetin, and CDC inhibited both 12S-HETE and TXB₂ while ML-355 was almost ineffective. In PRP, ML-355, CDC, and esculetin did not affect platelet aggregation associated with incomplete effects on eicosanoid biosynthesis. ASA alone or in combination with ticagrelor(a P2Y₁₂ blocker) affected platelet aggregation associated with profound inhibition of TXB₂ generation. P2Y₁₂ receptor signaling contributed to platelet 12S-HETE biosynthesis in response to primary agonists. In conclusion, ML-355, esculetin, and CDC were not selective inhibitors of p-12-LOX in different cellular systems. They did not affect platelet aggregation induced in PRP by collagen or TRAP-6. The characterization of 12-LOX inhibitors on eicosanoids generated in human whole blood is useful for information on their enzyme selectivity, off-target effects, and the possible influence of plasma components on their pharmacological effects.

Platelet Transfusion After Traumatic Intracranial Hemorrhage in Patients on Antiplatelet Agents

BACKGROUND

With an aging population, the number of patients on antiplatelet medications and traumatic brain injury (TBI) is increasing. Our study aimed to evaluate the role of platelet transfusion on outcomes after traumatic intracranial bleeding (IB) in these patients.

METHODS

We analyzed our prospectively maintained TBI database from 2014 to 2016. We included all isolated TBI patients with an IB, who were on preinjury antiplatelet agents and excluded patients taking anticoagulants. Outcome measures included the progression of IB, neurosurgical intervention, and mortality. Regression analysis was performed.

RESULTS

A total of 343 patients met the inclusion criteria. Mean age was 58 ± 11 y, 58% were men, and median injury severity score was 15 (10-24). Distribution of antiplatelet agents was as follows: aspirin (60%) and clopidogrel (35%). Overall, 74% patients received platelet transfusion after admission with a median number of two platelet units. After controlling for confounders, patients who received one unit of pooled platelets had no difference in progression of IB (odds ratio [OR]: 0.98, [0.6-1.9], P = 0.41), need for neurosurgical intervention (OR: 1.09, [0.7-2.5], P = 0.53), and mortality (OR: 0.84, [0.6-1.8], P = 0.51). However, patients who received two units of pooled platelets had lower rate of progression of IB (OR: 0.69, [0.4-0.8], P = 0.02), the need for neurosurgical intervention (OR: 0.81, [0.3-0.9], P = 0.03), and mortality (OR: 0.84, [0.5-0.9], P = 0.04). Both groups were compared with those who did not receive platelet transfusion.

CONCLUSIONS

The use of two units of platelet may decrease the risk of IB progression, neurosurgical intervention, and mortality in patients on preinjury antiplatelet agents and TBI. Further studies should focus on developing protocols for platelet transfusion to improve outcomes in these patients.

LEVEL OF EVIDENCE

Level III prognostic.