Bridging Anticoagulation Research Articles

Outcome and safety comparison of low-molecular-weight heparin versus unfractionated heparin for bridging anticoagulation in individuals with mechanical heart valves undergoing non-cardiac surgery: A systematic review and meta-analysis

In patients with mechanical heart valves, low-molecular-weight heparin (LMWH) and unfractionated heparin are commonly used as bridging anticoagulation therapies to reduce the risk of thromboembolic events and major adverse cardiac events; however, the efficacy and safety of these therapies remain debatable. The aim of this study was to compare the safety and outcomes of LMWH and unfractionated heparin in patients with mechanical heart valve replacement undergoing non-cardiac surgery. This systematic literature review was conducted from January to June 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to search for related studies through PubMed, ScienceDirect, and Cochrane Library. Categorical variables were analyzed using a Mantel-Haenszel random-effects model, with relative risk (RR) as the effect size. Higgins I2 was used to measure the heterogeneity and publication bias was assessed through funnel plots. Out of 814 potential studies, six studies (one randomized control trial and five prospective studies) were included. The analysis revealed no significant differences in thromboembolic event or valvular thrombosis (RR: 0.61; 95%CI: 0.36–1.04; p=0.07; ꭓ2=1.96; I2=0%), all-cause mortality (RR: 0.73; 95%CI: 0.40–1.35; p=0.32; ꭓ2=0.97; I2=0%), major bleeding (RR: 0.81; 95%CI: 0.53–1.23; p=0.33; ꭓ2=4.14; I2=0%), minor bleeding (RR: 1.18; 95%CI: 0.86–1.62; p=0.31; ꭓ2=4.50; I2=11%), and thrombocytopenia (RR: 0.56; 95%CI: 0.20–1.59; p=0.27; ꭓ2=0.85; I2=0%). The study highlights that LMWH and unfractionated heparin did not differ significantly when used as bridging anticoagulant therapy for non-cardiac surgery in mechanical heart valve patients.

Haemorrhagic and thromboembolic outcomes in pregnant patients with mechanical heart valves who undergo interruption of anticoagulation for birth - A case series.

Anticoagulant therapy prevents thrombosis and thromboembolic events in patients with mechanical heart valves. Bridging anticoagulation around the time of birth represents a unique challenge. Few retrospective reviews or case series exist examining peripartum outcomes with bridging anticoagulation. Review of peripartum and postpartum anticoagulation management, with a focus on postpartum complications. Design: case series, single centre. Royal Brisbane and Women's Hospital, Australia between 1 January, 2000, and 1 August, 2022. all pregnant women with mechanical heart valves (any type) who birthed. intrapartum and postpartum haemorrhage, thrombosis, thromboembolic complications, cardiac events, readmission, and maternal death. There were 18 women, with 23 births. Sixteen births were via caesarean section (70%). Fourteen women (61%) experienced at least one significant haemorrhagic complication, one woman required a peripartum hysterectomy, one woman experienced atrial fibrillation, and one had a valvular thromboembolic complication. No maternal cerebral thromboses or maternal deaths were recorded. Women with mechanical heart valves who undergo bridging anticoagulation are associated with significant maternal morbidity. Most postpartum haemorrhagic complications were associated with bridging unfractionated heparin infusions in the first postnatal week. Bridging anticoagulation practices varied widely. Ongoing pooled data are required to inform evidence-based guidelines for postpartum anticoagulation management.

International normalized ratio measurement during perioperative anticoagulation bridging with low-molecular-weight heparin in patients undergoing heart valve replacement surgery

BackgroundSurgical procedures in anticoagulated patients require specific attention due to increased bleeding risk. Preoperative anticoagulation interruption in high-risk patients is often necessary. Bridging anticoagulation with low-molecular-weight heparin (LMWH) minimizes thromboembolic risk, but its effect on international normalized ratio (INR) measurement is not well established, necessitating careful monitoring and individual assessment. ObjectivesTo investigate the effect of heparin bridging on INR measurements in anticoagulated patients on vitamin K antagonist (VKA) and in in vitro spiking experiments. MethodsThirty-eight anticoagulated patients on VKA undergoing valve replacement surgery were studied using 2 plasma-based INR assays and 1 whole blood point-of-care INR method at multiple time points after postoperatively resuming VKA. In addition, INR levels in pooled plasma of both normal and VKA-treated individuals were compared, with 7 spiked concentrations of LMWH or unfractionated heparin (UFH) in 4 INR assays. ResultsIn LMWH-bridged anticoagulated patients, the INR results obtained with HemosIL RecombiPlasTin and point-of-care Coaguchek were significantly higher than those obtained with STA Hepato Prest within 3 days after restart of VKA. After spiking LMWH or UFH in various concentrations into pooled plasma, only the STA Hepato Prest assay showed no interference in INR measurement within the therapeutic range (1.0-2.0 international units/mL) in both VKA and normal plasma. All other assays showed substantial interference, with the Thromborel S assay being the most heparin-sensitive assay. ConclusionDifferences between INR methods are seen within 72 hours after restarting VKA in postoperative patients who receive LMWH bridging. In vitro experiments using LMWH and UFH show the interference of heparin in multiple INR methods, even with concentrations below the suppliers’ stated heparin interference limits.

Optimal anticoagulation strategy for left ventricular assist device patients undergoing thoracentesis: a retrospective study

Abstract Background Left ventricular assist devices (LVADs) are associated with thromboembolic risks necessitating anticoagulation, yet balancing these risks with bleeding concerns remains challenging. Current practice involves warfarin with a target INR of 2-3 alongside anti-platelet therapy. However, consensus on anticoagulation management is lacking, particularly during sub-therapeutic INR or procedural settings. Common strategies include bridging anticoagulation with heparin or enoxaparin, temporary cessation of anticoagulation during the procedure or uninterrupted anticoagulation. Purpose To evaluate and compare the incidence of bleeding and thromboembolic events in LVAD patients undergoing thoracentesis, with a focus on determining the optimal anticoagulation strategy during procedures. Methods Retrospective data was collected over one year from LVAD patients undergoing thoracentesis at a large academic center. Patients were categorized into ‘bridge’ (received intravenous heparin for bridging during thoracentesis) and ‘no-bridge’ (did not receive bridging anticoagulation) groups. Warfarin was paused before procedure and resumed after procedure in both groups. Baseline characteristics, including age, sex, race, BMI, LVAD type, and INTERMACS profile, were recorded. Primary outcomes were major bleeding and thromboembolic events within 30 days of warfarin cessation. Statistical analysis used t-test/Wilcoxon for continuous variables and Chi-square/Fisher exact test for categorical variables. A p-value <0.05 was considered significant. Results During the study, twenty LVAD patients underwent thirty-two thoracenteses (nineteen bridge, thirteen no-bridge). The demographics were similar among the two groups. Warfarin was held for an average of 5.5 ± 4.6 days before and resumed 4.1 ± 4.6 days after the procedure in the bridge group and 3.8± 3.2 days before and 1.7 ± 2.5 days after in the no-bridge group. Major bleeding occurred in 73.7% of bridge group cases versus 30.8% of no-bridge group cases (p=0.059). 63.2% of bridge group patients had a bloody pleural effusion on thoracentesis compared to 46.2% of no-bridge group patients (p value= 0.34). Average transfusion requirements were 2.8 units and 2 units in the bridge and the no-bridge groups respectively (p=0.658). Thromboembolic events included a 10.5% ischemic CVA rate in the bridge group, with none in the no-bridge group. No other arterial thromboembolic events, pump thrombosis or DVT/PE were observed in either group. Conclusion In LVAD patients undergoing thoracentesis, a non-bridging strategy does not appear to elevate the risk of thrombosis compared to a bridging approach. Moreover, the incidence of bleeding, while not statistically significant, trended higher in the bridging group.

Assessing Direct Oral Anti-Coagulant And Therapeutic Low Molecular Weight Heparin Prescriptions At A University Teaching Hospital

Abstract Background A 2017-2018 survey identified anti-thrombotics as the most commonly implicated agents in reported medication incidents across Irish acute hospitals [State Claims Agency, 2020, Medication Incidents Report (2017-2018)]. Of the top 10 anti-thrombotics reported, 2 were Low Molecular Weight Heparins (LMWHs) and 3 were Direct Oral Anti-Coagulants (DOACs). 3 years after the survey results were published, we audited our hospital's compliance with the Health Service Executive's guidelines for prescribing DOACs and LMWHs. Methods Over 3 consecutive weeks, data was collected by doctors and clinical pharmacists across 6 wards and the intensive and coronary care units. In-patients on a DOAC or therapeutic LMWH were chosen for kardex and laboratory result review. Results 83 patients were included. The average age was 79 years. 81%(n=67) were on a DOAC. 91% were being treated for non-valvular atrial fibrillation (NVAF), 3% for pulmonary embolism (PE), 3% for deep vein thrombosis and 3% had no indication documented. 33%(n=22) had indications for dose reduction but only 77%(n=17) of them were prescribed the appropriate reduced dose. 3%(n=2) had no dose reduction indications but were inappropriately prescribed a reduced dose. 3%(n=2) were on dialysis, 1%(n=1) had their creatinine clearance persistently below 15ml/min and 1%(n=1) inappropriately received once daily dosing of apixaban for 3 days. 19%(n=16) of all participants were on therapeutic LMWH. Treatment indications included acute coronary syndrome in 63%, suspected PE in 19%, newly diagnosed NVAF in 6% and bridging anti-coagulation while a DOAC is temporarily held in 13%. 6%(n=1) were inappropriately prescribed an under-dose. Conclusion Overall, there was an error rate of 16%(n=11) in DOAC prescriptions and 6%(n=1) in LMWH prescriptions. To address this, we propose an educational intervention for prescribers and the introduction of e-prescriptions with built-in alerts for errors. We plan to re-audit once these recommendations are implemented.

Risk factors for MACE and bleeding in atrial fibrillation patients undergoing surgery: Insights from the bridge trial

IntroductionPatients with atrial fibrillation (AF) undergoing elective procedures are at risk for Major Adverse Cardiovascular Events (MACE) and symptomatic bleeding. We aimed to identify risk factors to guide perioperative risk stratification. MethodsWe conducted a post-hoc analysis of the “Bridging Anticoagulation in Patients who Require Temporary Interruption of Warfarin Therapy for an Elective Invasive Procedure or Surgery” randomized trial. The primary outcomes were MACE and symptomatic bleeding. Our statistical approach encompassed standard univariate analysis, logistic stepwise regression, and Cox regression models. Additional interaction analyses evaluated the interplay between low-molecular-weight heparin bridge therapy and other identified risk factors. ResultsAmong a total of 1,813 participants (mean age 71.6 ± 8.8, 73.3 % male), MACE occurred in 25 (1.4 %) individuals, with pre-procedure clopidogrel use (adjusted hazard ratio [aHR] 7.73, 95 % CI 2.63-22.72, p < 0.001) and CHA2DS2-VASc score ≥ 5 (aHR 2.89, 95 % CI 1.26-6.63, p = 0.012) identified as risk factors. Symptomatic bleeding occurred in 57 (3.1 %) individuals, with bridge therapy (aHR 1.84, 95 % CI 1.07-3.19, p = 0.029), renal disease (aHR 2.50, 95 % CI 1.34-4.67, p = 0.004), post-procedure aspirin use (aHR 2.86, 95 % CI 1.66-4.91, p < 0.001), post-procedure nonsteroidal anti-inflammatory drug use excluding aspirin (aHR 3.40, 95 % CI 1.22-9.43, p = 0.019), and major surgery (aHR 3.94, 95 % CI 2.26-6.85, p < 0.001) identified as risk factors. The interactions between risk factors and bridging therapy on MACE and symptomatic bleeding outcomes were not significant (p > 0.05). ConclusionWe identified predictors for MACE and symptomatic bleeding in AF patients undergoing elective procedures. These insights may help guide perioperative decisions to reduce the risk of adverse outcomes.

Perioperative Management of Anticoagulation and Antithrombotic Therapy

The latest updates to the NCCN Guidelines for perioperative management of anticoagulation and antithrombotic therapies reflect significant changes in the use of bridging anticoagulation. For patients with low- to intermediate-risk atrial fibrillation, the standard of care has shifted toward reduced reliance on bridging anticoagulation. The rationale for this shift is based on the BRIDGE trial, which revealed a 3-fold greater risk of major bleeding without significant reduction in thrombotic outcomes in patients receiving bridging therapy. In patients with mechanical heart valves, findings from the PERIOP2 study led to similar conclusions. Both of these studies have contributed to a paradigm shift in perioperative anticoagulation management, pivoting toward personalized therapy based on patient-specific bleeding and thrombotic risks. For emergent or elective surgeries, the NCCN Guidelines provide a framework for more individualized decision-making, emphasizing the need for ongoing cooperation among physicians, surgeons, and patients.

Anticoagulation Bridging in Patients With Left Ventricular Assist Device: A Regional Analysis of HeartMate 3 Recipients.

Advances in left ventricular assist device technologies have led to an improvement in pump hemocompatibility and outcomes. Because of concerns of thromboembolic complications in prior generations of left ventricular assist devices, bridging with parenteral anticoagulants was routinely. Management strategies of subtherapeutic INRs and their effects on the current generation of devices deserve review. We performed analysis of the MOMENTUM 3 trial including 6 centers in the mid-America region. Patients with subtherapeutic INRs (INR < 2) occurring after the index admission underwent chart review to determine the management strategies taken by clinicians. Strategies were divided into two groups, bridging or nonbridging. Of the 225 patients included in the analysis, 130 (58%) patients had a total of 235 subtherapeutic international normalized ratio (INR) events. Most (n = 179, 76.2%) of these INRs were not bridged (n = 100 warfarin dose adjustment, n = 79 no change in warfarin dose). Among those INRs (n = 56, 23.8%) treated with bridging, approximately half (n = 30, 53.6%) were treated with subcutaneous agents and other half (n = 26, 46.4%) were treated with intravenous agents. There was no difference in individual outcomes or composite endpoints of death, rehospitalization, CVA, or bleeding events between the groups.

Anticoagulant Management of Mechanical Heart Valve Patients During Perioperative Surgery: A Case Report

Background: Patients with mechanical heart valves require lifelong oral anticoagulation. It will be a dilemma if a patient with a mechanical heart valve has surgery. This case report aims to discuss how to interrupt oral anticoagulants and bridging therapy in patients with mechanical heart valves who will be undergoing non-cardiac surgery. Case Report: A 26-year-old pregnant woman, G1P0A0, aterm with a mechanical mitral valve, will have elective Sectio Caesarian Transperitonealis (SCTP) surgery and Intra Uterine Device (IUD) insertion. The patient had a history of mitral valve replacement surgery (MVR) in 2014 and was routinely treated with 4 mg of warfarin at night. From the examination, blood pressure was 120/80 mmHg, heart rate was 90 beats per minute, and pulse rate was 90 beats per minute. The ECG examination found sinus rhythm with 1st-degree atrioventricular block, right axis deviation, 90 beats per minute, and left atrial enlargement. We decided to have oral anticoagulant interruption and bridging therapy by stopping warfarin three days before surgery. When the international normalized ratio (INR) falls &lt;2, patients are given heparin injections (UFH) with an APTT target of 1.5-2.0 times from basic APTT. When the patient was about to be operated on, UFH was stopped 6 hours before surgery and resumed 12 hours after surgery. Warfarin was given one day postoperatively. Patients were adjusted to the dose of UFH according to the target. This patient had no thromboembolic events or bleeding before, during, or after surgery. The patient was allowed to be an outpatient and was given home therapy with Warfarin 5 mg at night. Results: We report a case of a 26-year-old female patient with a mechanical mitral valve who was going to undergo elective SCTP surgery and an IUD insertion. Patients at high risk of thrombo¬embolism due to surgery with a high risk of bleeding. Bridging therapy was performed using UFH. In the perioperative period, the patient did not experience thromboembolic events, and bleeding before, during, and after surgery could be well controlled. Conclusion: Perioperative management of patients with mechanical heart valves must be done carefully. Interruption of oral anticoagulants should be carefully considered considering the risk of thromboembolism and bleeding during the perioperative period. Guidelines recommend that in patients with mechanical heart valves, anticoagulation interruption for minor surgeries is avoided. Whereas in patients with major surgery, it is necessary to do bridging therapy with fast-acting anticoagulants such as UFH or LMWH. Keywords: mechanical heart valve, anticoagulant interruption, perioperative, bridging therapy Correspondence: Trisulo Wasyanto. Department of Cardiology and Vascular Medicine, Faculty of Medicine, Sebelas Maret University / Dr. Moewardi Hospital. Jl. Kol. Sutarto 132, Surakarta 57126, Central Java, Indonesia. Email: trisulo.wasyanto@staff.uns.ac.id. ORCID ID: 0000-0001-9900-0497. Mobile: +62811294225.

Perioperative bridging anticoagulation in patients receiving oral anticoagulants (OACs) undergoing elective surgery/procedures at King Chulalongkorn Memorial Hospital (KCMH), Thailand

Perioperative bridging anticoagulation in patients receiving oral anticoagulants (OACs) undergoing elective surgery/procedures at King Chulalongkorn Memorial Hospital (KCMH), Thailand

Annals for Hospitalists - April 2023

Annals for Hospitalists - April 2023

Risk-adjusted perioperative bridging anticoagulation reduces bleeding complications without increasing thromboembolic events in general and visceral surgery

BackgroundPerioperative bridging of oral anticoagulation increases the risk of bleeding complications after elective general and visceral surgery. The aim of this study was to explore, whether an individual risk-adjusted bridging regimen can reduce bleeding events, while still protecting against thromboembolic events.MethodsWe performed a quality improvement study comparing bridging parameters and postoperative outcomes before (period 1) and after implementation (period 2) of a new risk-adjusted bridging regimen. The primary endpoint of the study was overall incidence of postoperative bleeding complications during 30 days postoperatively. Secondary endpoints were major postoperative bleeding, minor bleeding, thromboembolic events, postoperative red blood cell transfusion, perioperative length-of-stay (LOS) and in-hospital mortality.ResultsA total of 263 patients during period 1 and 271 patients during period 2 were compared. The included elective operations covered the entire field of general and visceral surgery. The overall incidence of bleeding complications declined from 22.1% during period 1 to 10.3% in period 2 (p < 0.001). This reduction affected both major as well as minor bleeding events (8.4% vs. 4.1%; p = 0.039; 13.7% vs. 6.3%; p = 0.004). The incidence of thromboembolic events remained low (0.8% vs. 1.1%). No changes in mortality or length-of-stay were observed.ConclusionIt is important to balance the individual thromboembolic and bleeding risks in perioperative bridging management. The risk adjusted bridging regimen reduces bleeding events in general and visceral surgery while the risk of thromboembolism remains comparably low.

The bridging conundrum: perioperative management of direct oral anticoagulants for venous thromboembolism

Most patients diagnosed with venous thromboembolism (VTE) are currently treated with direct oral anticoagulants (DOACs). Before an invasive procedure or surgery, clinicians face the challenging decision of how to best manage DOACs. Should the DOAC be held, for how long, and are there instances where bridging with other anticoagulants should be considered? Although clinical trials indicate that most patients taking DOACs for atrial fibrillation do not require bridging anticoagulation, the optimal strategy for patients with a history of VTE is undefined. In this review, we present a case-based discussion for DOAC interruption perioperatively in patients receiving anticoagulation for management of VTE.

Perioperative management in chronically anticoagulated children undergoing tonsillectomy.

Tonsillectomy is a common procedure in children. Patients at high risk for thrombosis who require chronic anticoagulation therapy pose a special challenge when undergoing tonsillectomy, as bleeding may occur up to two weeks after surgery. Due to a lack of evidence-based data, there is no consensus on the best management for such patients. The objective of our manuscript is to review perioperative anticoagulation bridging strategies in children undergoing tonsillectomy. Retrospective case series of chronically anticoagulated patients at high risk for a thromboembolic event, who underwent tonsillectomy from 2010 to 2021. Patients whose anticoagulation treatment was discontinued due to a low risk of thromboembolic events were excluded. Four patients met inclusion criteria (age range 1.5-16.1 years). All patients were admitted prior to surgery for bridging therapy with intravenous unfractionated heparin (UFH) drip titrated to a therapeutic dose until 4-6 hours prior to surgery. The estimated blood loss during surgery was minimal in all surgeries. UFH was readministered per hospital protocol on the night of surgery and titrated to a therapeutic dose. Postoperative warfarin was restarted within 2 days for all patients. High-risk patients were kept in the hospital until postoperative day 6-8 due to concern for delayed bleeding. One patient was noticed to have blood-tinged sputum requiring no intervention, and none of the patients developed early or delayed hematemesis. Our data show that bridging therapy with UFH has been successful. Chronically anticoagulated patients undergoing tonsillectomy require multidisciplinary care for the management of their pre- and postoperative course.

Direct autotransfusion in the management of acute pericardial tamponade during catheter ablation for atrial fibrillation: An imperfect but practical method.

BackgroundAcute pericardial tamponade (APT) is one of the most serious complications of catheter ablation for atrial fibrillation (AF-CA). Direct autotransfusion (DAT) is a method of reinjecting pericardial blood directly into patients through vein access without a cell-salvage system. Data regarding DAT for APT are rare and provide limited information. Our present study aims to further investigate the safety and feasibility of DAT in the management of APT during the AF-CA procedure.Methods and resultsWe retrospectively reviewed 73 cases of APT in the perioperative period of AF-CA from January 2014 to October 2021 at our institution, among whom 46 were treated with DAT. All included patients successfully received emergency pericardiocentesis through subxiphoid access guided by X-ray. Larger volumes of aspirated pericardial blood (658.4 ± 545.2 vs. 521.2 ± 464.9 ml), higher rates of bridging anticoagulation (67.4 vs. 37.0%), and surgical repair (6 vs. 0) were observed in patients with DAT than without. Moreover, patients with DAT were less likely to complete AF-CA procedures (32/46 vs. 25/27) and had a lower incidence of APT first presented in the ward (delayed presentation) (8/46 vs. 9/27). There was no difference in major adverse events (death/disseminated intravascular coagulation/multiple organ dysfunction syndrome and clinical thrombosis) (0/0/1/0 vs. 1/0/0/0), other potential DAT-related complications (fever/infection and deep venous thrombosis) (8/5/2 vs. 5/3/1), and length of hospital stay (11.4 ± 11.6 vs. 8.3 ± 4.7 d) between two groups.ConclusionDAT could be a feasible and safe method to deal with APT during AF-CA procedure.

Perioperative bridging anticoagulation in patients with oral cancer surgery: a multicenter retrospective study

The number of patients administered oral antithrombotic drugs who require elective surgery has increased. Perioperative heparin bridging needs to be considered for patients at a high risk of thromboembolism. The present study investigated the effects of perioperative heparin bridging therapy on perioperative complications (postoperative bleeding and thrombotic events) in oral cancer surgery. The medical records of 98 patients who underwent oral cancer surgery with perioperative bridging therapy were retrospectively analyzed. Postoperative hemorrhage occurred in 16 patients (16.3%) and thrombotic events (deep venous thrombosis) in 5 (5.1%), which were higher than in other surgeries. A multivariate analysis identified the administration of prostaglandins as the only significant independent risk factor for postoperative hemorrhage, and a longer duration of postoperative heparin bridging therapy was associated with the incidence of deep venous thrombosis. The present results suggest a higher incidence of thrombotic and bleeding events in patients who underwent oral cancer surgery with heparin bridging, and the nature of surgery (such as revascularization and prolonged bed rest) may be a contributing factor. Future studies are needed to establish whether heparin bridging is effective in oral cancer surgery.

Computed tomography-guided microwave ablation for non-small cell lung cancer patients on antithrombotic therapy: a retrospective cohort study.

For non-small cell lung cancer (NSCLC) patients on antithrombotic therapy who are treated with microwave ablation (MWA), the transient interruption of antithrombotic agents may increase the risk of thromboembolism, and continuation of antithrombotic agents may increase the risk of intraprocedural hemorrhage. This retrospective cohort study aimed to explore the safety of MWA in patients with NSCLC on antithrombotic therapy. A total of 572 patients with NSCLC (antithrombotic therapy group: n=84, Group A; control group: n=488, Group B) who received MWA were included. Antithrombotic agent use was suspended before MWA and resumed as soon as possible after MWA. Hemorrhagic (hemothorax and hemoptysis) and thromboembolic complications (pulmonary embolism, cerebral infarction, and angina) were compared. Logistic regression analyses were used to investigate the predictors of hemorrhagic complications after MWA. Hemorrhagic complications occurred in 8 participants (9.5%) from Group A and 33 participants (6.8%) from Group B, and no statistically significant difference was found (P=0.365). There were 3 participants (0.5%) who developed thromboembolic complications, including 1 case (1.2%, 1/84) of pulmonary embolism in Group A, and 2 cases (0.4%, 2/488) of cerebral infarction or angina in Group B; no significant difference was found (P=0.923). In the subgroup analyses of Group A, no statistically significant difference of hemorrhagic (P>0.999) or thromboembolic complications (P>0.999) was found between patients who received and did not receive bridging anticoagulation with heparin. Logistic regression analyses revealed that direct contact of a tumor with vessels ≥2 mm was a predictor of hemorrhagic complications [hazard ratio (HR) =2.318; 95% confidence interval (CI): 1.215-4.420; P=0.011], while antithrombotic therapy was irrelevant. With the appropriate cessation and resumption of antithrombotic agents, patients with NSCLC on antithrombotic therapy have comparable incidence rates of hemorrhagic and thromboembolic complications after MWA to those of patients who are not on antithrombotic therapy. Therefore, with appropriate cessation, MWA appears to generally be safe for NSCLC patients on antithrombotic therapy.

Effectiveness of prophylactic clipping in preventing postpolypectomy bleeding in oral anticoagulant users: a propensity-score analysis

Evidence of prophylactic clipping is inconsistent except for proximal and large colonic lesions in the general population. Although warfarin and direct oral anticoagulants (DOACs) are significant risk factors of postpolypectomy bleeding (PPB), dedicated studies to examine the benefit of prophylactic clipping in these high-risk patients remain limited. We performed a propensity score-weighted retrospective cohort study from 2012 to 2020. Patients who received an oral anticoagulant and underwent colonoscopic polypectomy were included. Data were collected on baseline demographics, medications (anticoagulant, antiplatelet, and heparin bridging), and endoscopies (polyp number, location, size, morphology, histopathology, resection method and prophylactic clipping). Propensity-score models with inverse probability of treatment weighting were developed between prophylactic clipping and no clipping groups. Unbalanced variables were included in a doubly robust model with multivariate analysis. The primary outcome was clinically significant delayed PPB, defined as a composite endpoint of hemoglobin drop≥2 g/dL, blood transfusion, or repeat colonoscopy for hemostasis within 30 days. Five hundred forty-seven patients with 1485 polyps were included. Prophylactic clipping was not associated with a reduced risk of PPB (odds ratio [OR], 1.19; 95% confidence interval [CI], .73-1.95; P= .497). The hot resection method was associated with a significantly higher risk of PPB (OR, 9.76; 95% CI, 3.94-32.60; P< .001) compared with cold biopsy or snare polypectomy. In a subgroup analysis, prophylactic clipping was associated with a lower PPB risk in patients on DOACs (OR, .36; 95% CI, .16-.82; P= .015). Prophylactic clipping was not associated with an overall reduced risk of PPB in patients on oral anticoagulants. The use of cold snare polypectomy should be maximized in anticoagulated patients.

Safety of Once Daily Enoxaparin for Anticoagulation Bridging in Patients with HeartMate III Left Ventricular Assisted Device

<h3>Purpose</h3> Most centers bridge patients with Left Ventricular Assist Device (LVAD) patients with heparin drip to avoid thromboembolic complications based on data from HeartMate II. Because of improved hemocompatibility of third generation HeartMate III (HM3), Low molecule weight heparin like enoxaparin has been used to bridge to warfarin when the INR (International Normalized Ratio) is subtherapeutic. Once daily dosing has been used in select patients with higher bleeding risk. However, data supporting this approach is limited. We investigate the safety of using once daily Enoxaparin dosing to bridge subtherapeutic warfarin in patients on HMIII LVAD. <h3>Methods</h3> We conducted a retrospective review of patients who underwent HMIII LVAD implantation from 2018 to 2020. We identified 22 patients who received enoxaparin daily bridging after LVAD implantation. We investigated complications related to enoxaparin use and the necessary data parameters to determine the safety profile of once daily enoxaparin use. The primary outcome was in-pump thrombosis. Secondary outcomes included ischemic stroke, embolic phenomenon, acute kidney injury and bleeding events. <h3>Results</h3> 52 patients were screened, 22 patients of which bridged at least once with enoxaparin. 10 patients received multiple rounds of enoxaparin bridging over their course of follow up. The average enoxaparin course was 3-7 days and extended only if INR remains below 1.6. Enoxaparin was held once the INR reaches 1.8. There were no incidence of pump thrombosis, ischemic stroke or embolic phenomenon related to enoxaparin bridging. No significant events were noted in terms of worsening thrombocytopenia, anemia, renal function, bleeding events, or rates of infection. <h3>Conclusion</h3> Once daily enoxaparin dosing as a bridge to subtherapeutic anticoagulation with warfarin for HM III patients is a safe and effective method for preventing pump thrombosis while significantly reducing the need for hospital admissions for heparin bridging.

Adverse Events in HVAD vs. HM3 Patients under Outpatient Bridging with Low-Molecular Weight Heparin for Subtherapeutic Anticoagulation

<h3>Purpose</h3> The standard of care in patients with durable left-ventricular assist devices combines antiplatelet with anticoagulation therapy. Current guidelines recommend use of intravenous (IV) unfractionated heparin as bridge to therapeutic INR-values in the postoperative period. However, management of subtherapeutic INR in the ambulatory setting is not yet clearly defined by guidelines. The protocol at our center proposes the use of unfractionated heparin perioperatively and low-molecular weight heparin in outpatients. Therefore, we aimed to analyse outcomes in patients with continuous-flow LVAD (CF-LVAD). <h3>Methods</h3> In this single-center retrospective trial all patients after CF-LVAD implantation at our center were included between 1/2015 and 12/2020 (n=110 patients; HVAD n=80, HM3 n=30). Patients were followed up from initial discharge after LVAD implantation until death, heart transplantation or end of the observation period (9/2021). Bridging for subtherapeutic INR (≤ 0.4 below target INR) were provided with enoxaparin in a therapeutic dose adapted to weight and renal function. Only patients with an INR > 0.4 below target INR were admitted to hospital for bridging with IV unfractionated heparin. Bleeding events leading to hospital admission, cerebrovascular events and pump thromboses were evaluated and provided in percent of study population and/or events per patient year (eppy). <h3>Results</h3> Follow-up covers a total of 214.2 patient years. Overall mortality was 18.2 %. Bleeding events occurred in 42.7 %, of which GI bleeding constituted the largest group with 21.8 % (HVAD: 0.25 eppy; HM3: 0.05 eppy). Stroke/TIA/PRIND occurred in 5.5 % of the patients (HVAD: 0.07 eppy; HM3: 0.01 eppy; in total: 0.03 eppy). Intracerebral hemorrhage (overall 0.04 eppy) occurred 6.3 times more often in HVAD patients. Pump thrombosis occurred in 8.2 % of all CF-LVAD patients and was limited to HVAD (0.13 eppy). <h3>Conclusion</h3> Current studies tend to promote the use of low molecular weight heparins, especially enoxaparin for outpatient anticoagulation bridging in case of subtherapeutic INRs. However, in most cases old generation CF-LVADs were studied. Our study includes a relevant number of HM3 devices. Overall, the adverse event rates presented herein suggest feasibility of low-molecular weight heparin bridging in patients with HM3 devices.