State-of-art review: intravascular imaging in percutaneous coronary interventions

The history of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) reflects the relentless pursuit of innovation in interventional cardiology. These intravascular imaging technologies have played a pivotal role in our understanding of coronary atherosclerosis, vascular pathology, and the interaction of coronary stents with the vessel wall. Two decades of clinical investigations demonstrating the clinical efficacy and safety of intravascular imaging modalities have established these technologies as staples in the contemporary cardiac catheterization lab's toolbox and earning their place in revascularization clinical practice guidelines. In this comprehensive review, we will delve into the historical evolution, mechanisms, and technical aspects of IVUS and OCT. We will discuss the expanding evidence supporting their use in complex percutaneous coronary interventions, emphasizing their crucial roles in optimizing patient outcomes and ensuring procedural success. Furthermore, we will explore the substantial advances that have propelled these imaging modalities to the forefront of contemporary interventional cardiology. Finally, we will survey the latest developments in the field and explore the promising future directions that have the potential to further revolutionize coronary interventions.

Impact of malignancy on In-hospital mortality, stratified by the cause of admission: An analysis of 67 million patients from the National Inpatient Sample

OBJECTIVE

To describe the patient characteristics and the reason for admission of patients with malignancy by malignancy, and to study mortality rates for the different causes of admissions among the different types of cancer.

PATIENTS AND METHODS

Using the nationwide Inpatient Sampling (2015-2017) we examined the cause of admission and associated in-hospital mortality, stratified by presence and type of malignancy. Multivariable logistic regression models were used to examine the association between in-hospital mortality and malignancy sites for different primary admission causes.

RESULTS

Out of 67 819 693 inpatient admissions, 8.8% had malignancy. Amongst those with malignancy, haematological malignancy was the most common (20.2%). The most common cause of admission amongst all cancers were malignancy-related admissions, where up to 57% of all colorectal admissions were malignancy-related. The most common non-malignancy cause of admission was infectious causes, which were most frequent among patients with haematological malignancy (18.4%). Patients with malignancy had higher crude mortality rates (5.7% vs 1.9%). Mortality rates were highest among patients with lung cancer (8.7%). Among all admissions, the adjusted rates of mortality were higher for patients with lung (OR 3.65, 95% CI [3.59-3.71]), breast (OR 2.06, 95% CI [1.99-2.13]), haematological (OR 1.79, 95% CI [1.76-1.82]) and colorectal (OR 1.71, 95% CI [1.66-1.76]) malignancies compared with patients with no malignancy.

CONCLUSION

Our work highlights the need to consider the burden of cancer on our hospital services and consider how the prognostic impact of different types of admissions may relate to the type of cancer diagnosis and understand whether these differences relate to disparities in clinical care/treatments.

A virtual-hybrid approach to launching a cardio-oncology clinic during a pandemic

BACKGROUND

As cardiovascular disease is a leading cause of death in cancer survivors, the new subspecialty of Cardio-Oncology has emerged to address prevention, monitoring, and management of cardiovascular toxicities to cancer therapies. During the coronavirus disease of 2019 (COVID-19) pandemic, we developed a Virtual-Hybrid Approach to build a de novo Cardio-Oncology Clinic.

METHODS

We conceptualized a Virtual-Hybrid Approach including three arms: information seeking in locations with existing Cardio-Oncology clinics, information gathering at the location for a new clinic, and information sharing to report clinic-building outcomes. A retrospective review of outcomes included collection and synthesis of data from our first 3 months (at pandemic peak) on types of appointments, cancers, drugs, and cardiotoxicities. Data were presented using descriptive statistics.

RESULTS

A de-novo Cardio-Oncology clinic was developed structured from the ground up to integrate virtual and in-person care in a hybrid and innovative model, using the three arms of the Virtual-Hybrid Approach. First, we garnered in-person and virtual preparation through hands-on experiences, training, and discussions in existing Cardio-Oncology Clinics and conferences. Next, we gleaned information through virtual inquiry and niche-building. With partners throughout the institution, a virtual referral process was established for outpatient referrals and inpatient e-consult referrals to actualize a hybrid care spectrum for our patients administered by a multidisciplinary hybrid care team of clinicians, ancillary support staff, and clinical pharmacists. Among the multi-subspecialty clinic sessions, approximately 50% were in Cardio-Oncology, 20% in Preventive Cardiology, and 30% in General Cardiology. In the hybrid model, the Heart & Vascular Center had started to re-open, allowing for 65% of our visits to be in person. In additional analyses, the most frequent cardiovascular diagnosis was cardiomyopathy (34%), the most common cancer drug leading to referral was trastuzumab (29%), and the most prevalent cancer type was breast cancer (42%).

CONCLUSION

This Virtual-Hybrid Approach and retrospective review provides guidance and information regarding initiating a brand-new Cardio-Oncology Clinic during the pandemic for cancer patients/survivors. This report also furnishes virtual resources for patients, virtual tools for oncologists, cardiologists, and administrators tasked with starting new clinics during the pandemic, and innovative future directions for this digital pandemic to post-pandemic era.

Relation of White Blood Cell Count to Bleeding and Ischemic Events in Patients With Acute Coronary Syndrome (from the ATLAS ACS 2-TIMI 51 Trial)

An elevated white blood cell (WBC) count is associated with an increased risk of ischemic events among acute coronary syndrome (ACS) patients, but the association between WBC count and bleeding in ACS patients is not well established. The aim of this analysis was to assess and compare the association between WBC count and the occurrence of short- and long-term bleeding and ischemic events. This was a post hoc analysis of the ATLAS ACS2-TIMI 51 trial. A subset of patients had a WBC count measurement at baseline (n = 14,231, 91.6%). Univariate and multivariable Cox proportional hazard models were constructed to determine if there is an association between WBC count at baseline and a composite outcome of Thrombolysis in Myocardial Infarction (TIMI) major and minor bleeds at 30 days and 1 year. Variables with a p <0.2 in the univariate analysis were included as potential parameters in the backward selection process A similar multivariable model was constructed to assess the association between WBC count and a composite ischemic endpoint of cardiovascular death, myocardial infarction and stroke. An increased risk of bleeding per a 1 × 10⁹/L increase in WBC at baseline was observed at 30 days (Adjusted hazard ratio [HR] 1.08 95% confidence interval [CI] 1.01 to 1.17, p = 0.019) but not at 1 year (Adjusted HR 1.02 95% CI 0.97 to 1.08, p = 0.409). Additionally, an increased risk of ischemia per a 1 × 10⁹/L increase in WBC at baseline was observed at 30 days (Adjusted HR 1.07, 95% CI: 1.03 to 1.12, p = 0.002) and at 1 year (Adjusted HR 1.05 95% CI 1.02 to 1.08, p = 0.001 at 1 year). In conclusion, a higher WBC count at baseline was associated with an increased risk of the composite bleeding endpoint by 30 days but not at 1 year. The association between WBC count and the risk of the composite ischemic endpoint was significant at 30 days and 1 year.

Machine learning to predict venous thrombosis in acutely ill medical patients

BACKGROUND

The identification of acutely ill patients at high risk for venous thromboembolism (VTE) may be determined clinically or by use of integer-based scoring systems. These scores demonstrated modest performance in external data sets.

OBJECTIVES

To evaluate the performance of machine learning models compared to the IMPROVE score.

METHODS

The APEX trial randomized 7513 acutely medically ill patients to extended duration betrixaban vs. enoxaparin. Including 68 variables, a super learner model (ML) was built to predict VTE by combining estimates from 5 families of candidate models. A "reduced" model (rML) was also developed using 16 variables that were thought, a priori, to be associated with VTE. The IMPROVE score was calculated for each patient. Model performance was assessed by discrimination and calibration to predict a composite VTE end point. The frequency of predicted risks of VTE were plotted and divided into tertiles. VTE risks were compared across tertiles.

RESULTS

The ML and rML algorithms outperformed the IMPROVE score in predicting VTE (c-statistic: 0.69, 0.68 and 0.59, respectively). The Hosmer-Lemeshow goodness-of-fit P-value was 0.06 for ML, 0.44 for rML, and <0.001 for the IMPROVE score. The observed event rate in the lowest tertile was 2.5%, 4.8% in tertile 2, and 11.4% in the highest tertile. Patients in the highest tertile of VTE risk had a 5-fold increase in odds of VTE compared to the lowest tertile.

CONCLUSION

The super learner algorithms improved discrimination and calibration compared to the IMPROVE score for predicting VTE in acute medically ill patients.

The AngelMed Guardian® System in the Detection of Coronary Artery Occlusion: Current Perspectives

Total ischemic time, which specifies the time from the onset of chest pain to initiation of reperfusion during percutaneous coronary intervention, consists of two intervals: symptom to door time and door to balloon time. A door to balloon time of 90 mins or less has become a quality-of-care metric in the management of ST elevation myocardial infarction (STEMI). While national efforts made by the American College of Cardiology (ACC) and American Heart Association (AHA) have curtailed in-hospital door to balloon time over the years, a reduction in pre-hospital symptoms to door time presents a challenge in modern interventional Cardiology. Early and complete revascularization has been associated with improved clinical outcomes in MI and strategies that may help reduce symptom to door time, and thus the total ischemic time, are crucial. Rapidly evolving ST-segment changes commonly develop prior to ischemia-related symptom onset, and are detectable even in patients with clinically unrecognized silent MIs. Therefore, a highly intelligent ischemia detection system that alerts patients of ST segment deviation may allow for rapid identification of acute coronary occlusion. The AngelMed Guardian^® System is a cardiac activity monitoring and alerting system designed for rapid identification of intracardiac ST-segment changes among patients at a high risk for recurrent ACS events. This article reviews the clinical studies evaluating the design, safety and efficacy of the AngelMed Guardian System and discusses the clinical implications of the device.

Novel Oral Anticoagulant Based Versus Vitamin K Antagonist Based Double Therapy Among Stented Patients With Atrial Fibrillation: Insights From the PIONEER AF-PCI Trial

BACKGROUND

Among stented patients with atrial fibrillation, double therapy with a novel oral anticoagulant plus single antiplatelet therapy (SAPT) reduces bleeding or cardiovascular rehospitalizations compared with a vitamin K antagonist (VKA) based triple therapy regimen. A recent study demonstrated that apixaban based double therapy reduced bleeding compared with VKA based double therapy. However, it remains unknown whether rivaroxaban based double therapy is superior to a VKA based double therapy.

METHODS

Patient with stented atrial fibrillation (n=2124) were randomized to 3 groups: rivaroxaban 15 mg od plus a P2Y₁₂ inhibitor (Group 1, n=709); rivaroxaban 2.5 mg bid plus dual antiplatelet therapy (DAPT; Group 2, n=709); and warfarin plus DAPT (Group 3, n=706). Before randomization, subjects were stratified according to a prespecified duration of DAPT (1, 6, or 12 months). After the prespecified DAPT duration, subjects in Group 2 were switched to rivaroxaban 15 mg plus low dose aspirin, and those in Group 3 were switched to VKA plus low dose aspirin. The Wei, Lin, and Weissfeld time to multiple events method was used to compare the occurrence of all bleeding and cardiovascular rehospitalizations among subjects on a novel oral anticoagulant versus VKA based double therapy.

RESULTS

A total of 906 subjects were prespecified to a 1 or 6 months DAPT duration and received at least one dose of study drug. Twenty subjects (3.3%) assigned to novel oral anticoagulant+SAPT, and 15 (5.1%) subjects assigned to VKA+SAPT experienced multiple rehospitalizations. In total, 124 (20.3%) events occurred among subjects on novel oral anticoagulant+SAPT compared with 87 (29.6%) among subjects on VKA+SAPT (hazard ratio=0.65 [95% CI, 0.45-0.93], P=0.008).

CONCLUSIONS

Among stented patients with atrial fibrillation, rivaroxaban plus SAPT was superior to warfarin plus SAPT in lowering total bleeding and cardiovascular rehospitalization.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01830543.

Characterization of Major and Clinically Relevant Non-Major Bleeds in the APEX Trial

Background  Among medically ill patients treated with thromboprophylaxis, betrixaban was not associated with an increase in major bleeding compared with enoxaparin, but an increase in clinically relevant non-major (CRNM) bleeding was observed. The aim of this analysis is to describe the severity and clinical consequences of major and CRNM bleeding in the APEX trial.

Methods  The APEX trial randomized 7,513 hospitalized acutely ill medical patients to receive either enoxaparin for 6 to 14 days or betrixaban for 35 to 42 days. Subjects receiving a concomitant strong p-glycoprotein inhibitor or with creatinine clearance <30 mL/min were administered a reduced dose of study drug.

Results  A total of 25 (0.7%) and 21 (0.6%) major bleeds occurred in the betrixaban and enoxaparin arms, respectively ( p  = NS) and a total of 91 (2.5%) and 38 (1.0%) CRNM bleeds occurred in the betrixaban and enoxaparin arm ( p  < 0.001), respectively. Most major bleeds were considered moderate or severe and most CRNM bleeds were considered mild and moderate ( p  = NS). One fatal major bleed occurred in each treatment arm. Rates of major or CRNM bleeds resulting in new or prolonged hospitalization (major: 44.0 vs. 28.6%; CRNM: 12.1 vs. 21.1%) or study treatment interruption or cessation (major: 72.0 vs. 71.4%; CRNM: 71.3 vs. 68.4%) were similar between treatment arms ( p  = NS).

Conclusions  In the APEX trial, CRNM bleeds were mild or moderate in nature and had less of a clinical impact than major bleeds. The severity and clinical sequela of bleeds in the betrixaban arm were comparable to those in the enoxaparin arm.

Clinical Trial Registration  URL: http://www.clinicaltrials.gov .; Unique identifier: NCT01583218.

Asymptomatic Deep Vein Thrombosis is Associated with an Increased Risk of Death: Insights from the APEX Trial

AIM

 Asymptomatic deep vein thrombosis (DVT) diagnosed with compression ultrasound (CUS) is a common endpoint in trials assessing the efficacy of anticoagulants to prevent venous thromboembolism (VTE), but the relationship of asymptomatic thrombus to mortality remains uncertain.

METHODS

 In the APEX trial (ClinicalTrials.gov: NCT01583218), 7,513 acutely ill hospitalized medical patients were randomly assigned to extended-duration betrixaban (35-42 days) or enoxaparin (10 ± 4 days). Asymptomatic DVT was assessed once with CUS between day 32 and 47, and mortality was assessed through 77 days.

RESULTS

 A total of 309 asymptomatic DVTs were detected through CUS. Of these, 133 (4.27%) subjects were in the betrixaban group, and 176 (5.55%) subjects were in the enoxaparin group (relative risk = 0.77, 95% confidence interval [CI] = 0.62-0.97, p = 0.025, number needed to treat = 79). With respect to all-cause mortality due to cardiovascular diseases, non-cardiovascular diseases and unknown causes, the number of the deaths was 5 (1.67%), 4 (1.34%) and 1 (0.33%) in the asymptomatic DVT group and 25 (0.42%), 33 (0.56%) and 11 (0.19%) in the no DVT group, respectively. Subjects with an asymptomatic DVT had an almost threefold increase in the risk of all-cause mortality compared with subjects without DVT (hazard ratio = 2.87, 95% CI = 1.48-5.57, p = 0.001). A positive linear trend was observed between greater thrombus burden and mortality during the follow-up (p = 0.019).

CONCLUSION

 Asymptomatic DVT was associated with approximately threefold increased risk of short-term all-cause mortality in patients hospitalized with an acute medical illness within the prior 77 days. A positive linear trend was observed between greater thrombus burden and mortality during the follow-up.

D-Dimer Levels and Effect of Rivaroxaban on Those Levels and Outcomes in Patients With Acute Coronary Syndrome (An ATLAS ACS-TIMI 46 Trial Substudy)

D-dimer has been used as both a diagnostic and prognostic biomarker in the assessment of patients with venous thromboembolism, but its prognostic value in the setting of arterial acute coronary syndromes (ACS) and the ability of pharmacotherapy to reduce D-dimer in ACS is less well characterized. It was hypothesized that elevated baseline D-dimer would be associated with poor clinical outcomes in ACS, and that Factor Xa inhibition with Rivaroxaban would reduce D-dimer acutely and chronically. The ATLAS ACS TIMI-46 trial assessed the safety and efficacy of rivaroxaban compared with placebo in ACS patients. A subset of subjects had a D-dimer measured at baseline (n = 1,834, 52.5%). A univariate and multivariable logistic regression assessed the relation between baseline D-dimer and a composite end point of cardiovascular death, myocardial infarction, or stroke through 6 months. The Wilcoxon rank sum test was used to compare change in D-dimer level between the treatment groups from baseline. Baseline D-dimer was associated with the composite efficacy outcome in a univariate logistic regression (odds ratio 1.15, 95% confidence interval 1.03 to 1.29, p = 0.015) and a multivariable logistic regression (odds ratio 1.13, 95% confidence interval 1.00 to 1.28, p = 0.048). Rivaroxaban administration lowered D-dimer levels compared wth placebo after administration of the first dose of study drug (p = 0.026), at day 30 (p < 0.001) and day 180 (p < 0.001). In conclusion, elevated baseline D-dimer was associated with an increased risk of the composite outcome within 6 months of the ACS event and administration of the Factor Xa inhibitor rivaroxaban was associated with lower D-dimer levels compared with placebo after the first dose, at day 30 and day 180.

Betrixaban for first-line venous thromboembolism prevention in acute medically ill patients with risk factors for venous thromboembolism

INTRODUCTION

Compared to other direct oral anticoagulants, betrixaban has a longer half-life, smaller peak-trough variance, minimal renal clearance, and minimal hepatic Cytochrome P (CYP) metabolism. The Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial evaluated the efficacy and safety of extended duration betrixaban compared to standard duration enoxaparin in acutely ill hospitalized patients. Areas covered: This article describes the role of betrixaban in the prevention of venous thromboembolism (VTE) in acutely ill medical patients. This article provides a consolidated summary of the primary APEX study findings as well as prespecified and exploratory substudies. This article also provides a review of the results of studies in which other direct factor Xa inhibitors have been evaluated in an extended duration regimen in this patient population. Expert commentary: While previous agents have demonstrated that extended duration VTE prophylaxis can be efficacious, betrixaban is the first agent to demonstrate efficacy without an increase in major bleeding. The totality of the data from the APEX trial supports extended duration betrixaban for VTE prophylaxis in the acute medically ill patient population. As such, betrixaban has been approved in the USA for extended VTE prophylaxis in at-risk acute medically ill patients.

Increased benefit of betrixaban among patients with a history of venous thromboembolism: a post-hoc analysis of the APEX trial

Hospitalized acute medically ill patients with a history of venous thromboembolism (VTE) are at increased risk for recurrent VTE. We characterized the efficacy and safety of betrixaban for prevention of recurrent VTE in these high risk patients. The APEX trial randomized 7513 acutely ill hospitalized medical patients at risk for developing VTE to receive either betrixaban for 35-42 days or enoxaparin for 10 ± 4 days to prevent VTE. This exploratory post-hoc analysis assessed the efficacy and safety of betrixaban versus enoxaparin among subjects with and without prior VTE. Time-to-multiple symptomatic VTE events was also calculated. Approximately 8% of subjects in both arms had prior VTE, which was associated with a fourfold increase in adjusted risk of VTE [MV OR 4.03, 95% CI 3.06-5.30, p < 0.001]. Betrixaban reduced VTE compared with enoxaparin among subjects with prior VTE [32 (10.4%) vs. 55 (18.9%), RR 0.57, 95% CI 0.38-0.86, p = 0.006, ARR 8.5%, NNT 12] and without prior VTE [133 (3.9%) vs. 168 (4.9%), RR 0.79, 95% CI 0.64-0.99, p = 0.042, ARR 1.0%, NNT 100] (interaction p > 0.05). Additionally, four subjects in the enoxaparin arm and one subject in the betrixaban arm experienced a recurrent VTE. Compared with enoxaparin, betrixaban use was associated with reduction of recurrent VTE events through the active treatment period [36 vs. 57, HR 0.63, 95% CI 0.41-0.97, p = 0.045] and through the end of study [38 vs. 71, HR 0.54, 95% CI 0.36-0.81, p = 0.004]. Prior VTE is associated with a fourfold increase in the risk of VTE among hospitalized medically ill patients. Only 12 such patients would need to be treated with betrixaban versus enoxaparin to prevent an additional VTE endpoint. Betrixaban reduced not only the first but also all recurrent VTE events in a time-to-any-event analysis.

TRIAL REGISTRATION

http://www.clinicaltrials.gov , Unique identifier: NCT01583218.

Association of Anemia with Venous Thromboembolism in Acutely Ill Hospitalized Patients: An APEX Trial Substudy

BACKGROUND

Anemia is a common finding and independent predictor for adverse outcomes in hospitalized patients with medical illness. It remains unclear whether anemia is a risk factor for venous thromboembolism and whether the presence of anemia can refine risk assessment for prediction of venous thromboembolism, thereby adding incremental utility to a validated model.

METHODS

In the Acute Medically Ill Venous Thromboembolism Prevention with Extended Duration Betrixaban trial (APEX), 7513 hospitalized medical patients were randomized to receive either betrixaban or standard-of-care enoxaparin for thromboprophylaxis. Baseline hemoglobin concentrations were obtained in 6861 patients, with a follow-up of 77 days. Symptomatic venous thromboembolism events, including symptomatic deep vein thrombosis, pulmonary embolism, and venous thromboembolism-related mortality, were compared between low-hemoglobin and normal-hemoglobin groups (normal range: 12.5-17.0 g/dL for males and 11.0-15.5 g/dL for females). The relationship between anemia and venous thromboembolism events was assessed by fitting a univariable and multivariable logistic regression model composed of thromboprophylaxis and risk factors. Venous thromboembolism risk refinement by hemoglobin measurement was evaluated in the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) risk assessment model.

RESULTS

Low hemoglobin at baseline was associated with a greater risk of symptomatic venous thromboembolism (relative risk [RR] 1.94 [95% confidence interval, 1.27-2.98]; P = .002), symptomatic deep vein thrombosis (RR 2.29 [1.12-4.68]; P = .019), and nonfatal pulmonary embolism (RR 2.63 [1.22-5.65]; P = .010) but not venous thromboembolism-related mortality (RR 1.47 [0.71-3.04]; P = .30). After adjusting for thromboprophylaxis, history of previous venous thromboembolism, intensive or coronary unit admission, and D-dimer, low hemoglobin (as a categorical or continuous variable) remained associated with an increased likelihood of venous thromboembolism (adjusted odds ratio 1.71 [95% confidence interval, 1.09-2.69]; P = .020). Low hemoglobin also improved risk discrimination and reclassification after inclusion in the IMPROVE model.

CONCLUSIONS

Anemia was independently associated with a greater risk of symptomatic venous thromboembolism among acutely ill medical patients despite the provision of thromboprophylaxis. Hemoglobin measurement also improved risk stratification by the IMPROVE venous thromboembolism risk score.

Symptomatic event reduction with extended-duration betrixaban in acute medically ill hospitalized patients

BACKGROUND

Approximately 15%-30% of patients in trials of medical thromboprophylaxis will have missing compression ultrasound (CUS) data. The goal of the present analysis was to perform analyses to minimize missing data.

METHODS

The APEX trial randomized 7,513 acutely medically ill hospitalized patients to thromboprophylaxis with either betrixaban for 35-42 days or enoxaparin for 6-14 days. A modified intent-to-treat (mITT) analysis was performed and included all subjects administered study drug, irrespective of CUS performance, and an analysis of symptomatic events which do not require performance of a CUS (symptomatic deep vein thrombosis, nonfatal pulmonary embolism, and venous thromboembolism (VTE)-related mortality).

RESULTS

In the mITT population, betrixaban significantly reduced the primary end point (which included both symptomatic and CUS events) (165 [4.4%] vs 223 [6.0%]; relative risk = 0.75; 95% CI 0.61-0.91; P = .003; absolute risk reduction [ARR] = 1.6%; number needed to treat [NNT] = 63). Betrixaban also reduced symptomatic VTE through day 42 (35 [1.28%] vs 54 [1.88%], hazard ratio [HR] = 0.65; 95% CI 0.42-0.99; P = .044; ARR = 0.6%; NNT=167) as well as through day 77 (37 [1.02%] vs 67 [1.89%]; HR= 0.55; 95% CI 0.37-0.83; P = .003; ARR = 0.87%; NNT=115) as well as the individual end point of nonfatal pulmonary embolism (9 [0.25%] vs 20 [0.55%]; HR= 0.45; 95% CI 0.21-0.99; P = .041; ARR = 0.30%; NNT=334). On an "as-treated" basis, 80 mg of betrixaban reduced VTE-related mortality through day 77 (10 [0.34%] vs. 22 [0.79%]; HR=0.46; 95% CI 0.22-0.96; P = .035; ARR = 0.45%; NNT=223).

CONCLUSION

In an mITT analysis of all patients administered study drug, extended-duration betrixaban reduced the primary end point as well as symptomatic events. In an as-treated analysis, 80 mg of betrixaban reduced VTE-related death.

Beyond Stroke Prevention in Atrial Fibrillation: Exploring Further Unmet Needs with Rivaroxaban

With improved life expectancy and the aging population, the global burden of atrial fibrillation (AF) continues to increase, and with AF comes an estimated fivefold increased risk of ischaemic stroke. Prophylactic anticoagulant therapy is more effective in reducing the risk of ischaemic stroke in AF patients than acetylsalicylic acid or dual-antiplatelet therapy combining ASA with clopidogrel. Non-vitamin K antagonist oral anticoagulants are the standard of care for stroke prevention in patients with non-valvular AF. The optimal anticoagulant strategy to prevent thromboembolism in AF patients who are undergoing percutaneous coronary intervention and stenting, those who have undergone successful transcatheter aortic valve replacement and those with embolic stroke of undetermined source are areas of ongoing research. This article provides an update on three randomized controlled trials of rivaroxaban, a direct, oral factor Xa inhibitor, that are complete or are ongoing, in these unmet areas of stroke prevention: oPen-label, randomized, controlled, multicentre study explorIng twO treatmeNt stratEgiEs of Rivaroxaban and a dose-adjusted oral vitamin K antagonist treatment strategy in patients with Atrial Fibrillation who undergo Percutaneous Coronary Intervention (PIONEER AF-PCI) trial; the New Approach riVaroxaban Inhibition of factor Xa in a Global trial vs Aspirin to prevenT Embolism in Embolic Stroke of Undetermined Source (NAVIGATE ESUS) trial and the Global study comparing a rivAroxaban-based antithrombotic strategy to an antipLatelet-based strategy after transcatheter aortIc vaLve rEplacement to Optimize clinical outcomes (GALILEO) trial. The data from these studies are anticipated to help address continuing challenges for a range of patients at risk of stroke.

Association of D-dimer Levels with Clinical Event Rates and the Efficacy of Betrixaban versus Enoxaparin in the APEX Trial

Background  Elevated D-dimer concentrations are associated with an increased risk of venous thromboembolism (VTE). However, they may also provide prognostic value. The present analysis sought to study the association of D-dimer levels with VTE event rates and the efficacy of betrixaban versus enoxaparin in the APEX trial. Methods  Hospitalized acutely medically ill subjects ( n  = 7,513) were randomized in a double-dummy double-blind fashion to either extended-duration oral betrixaban (80 mg once daily for 35-42 days) or standard dose subcutaneous enoxaparin (40 mg once daily for 10 ± 4 days) for venous thromboprophylaxis. D-dimer was assessed using a central core laboratory measurement. Results  For every 0.25 µg/mL increase in D-dimer concentration, there was a 2% increase in the relative risk of experiencing the primary efficacy endpoint (asymptomatic deep vein thrombosis [DVT], symptomatic DVT, nonfatal pulmonary embolism, or VTE-related death) in both the betrixaban ( p  < 0.001) and enoxaparin ( p  < 0.001) treatment arms. Among D-dimer-positive (≥ 2 × upper limit of normal; corresponding to ≥ 1.00 µg/mL) subjects, extended-duration betrixaban reduced the risk of experiencing the primary efficacy outcome (5.4% [ n  = 124] vs. 7.6% [ n  = 170]; odds ratio = 0.69; 95% confidence interval: 0.55-0.88; absolute risk reduction = 2.2%, number needed to treat = 46, p  = 0.003). There was no interaction between D-dimer and the treatment effect ( p int  = 0.53). Conclusion  Extended-duration betrixaban was superior to standard-duration enoxaparin, irrespective of D-dimer level at baseline. To prevent one VTE event, 46 D-dimer-positive patients would need to be treated with betrixaban.

Abstract 521: A Pilot Study Comparing Anti-Inflammatory Effects of Tranexamic Acid and Epsilon Aminocaproic Acid in Pediatric Congenital Heart Surgery

Background: Antifibrinolytic agents are frequently used during pediatric heart surgery with cardiopulmonary bypass (CPB) to reduce transfusions. There are no studies comparing anti-inflammatory effects of antifibrinolytic agents, tranexamic acid (TXA) and Epsilon Aminocaproic acid (EACA). We compared the two agents in pediatric patients undergoing redo sternotomy with CPB.

Aim: To compare anti-inflammatory effects of tranexamic acid versus aminocaproic acid in pediatric patients undergoing redo sternotomy and cardiopulmonary bypass.

Methods: We conducted a randomized, double blind pilot study, comparing 10 subjects in each group receiving EACA and TXA. A cytokine panel was used to measure 13 inflammatory markers in pre, immediate post and 24 hours post-CPB period. Between group comparisons were tested with Mann-Whitney U tests and within group comparisons with Friedman tests.

Results: Sample characteristics were comparable in both groups. Post CPB, plasma levels of 7 markers increased significantly (p<0.05) in both groups, including MCP-1; 3 increased significantly (p<0.03) in the EACA group alone, including GM-CSF; and 3 did not change over time (Table 1). No difference was found between groups for markers except for IL-10, which was significantly higher in EACA group post CPB. While absolute values of markers, chest tube output and volume of blood product needs were lower in TXA group, the differences were not statistically significant.

Conclusion: There was no significant difference in anti-inflammatory profiles between EACA and TXA in this pilot study. GM-CSF and MCP-1 were increased in our study post CBP which has not been described in previous studies.

Andexanet alfa for the reversal of anticoagulant activity in patients treated with direct and indirect factor Xa inhibitors

INTRODUCTION

Andexanet alfa is a recombinant factor Xa decoy molecule that inhibits direct and indirect factor Xa inhibitors to allow the normal coagulation process to resume. Its development arises in a space where novel oral anticoagulants are receiving expanded indications yet their use is limited by the lack of an effective reversal agent. Areas covered: This article reviews the biochemical properties, mechanism of action and the preclinical and clinical trials on andexanet alfa. It additionally aims to provide expert commentary and future perspectives on the efficacy, safety and challenges facing andexanet alfa as a universal antidote for direct and indirect factor Xa inhibitors. Expert commentary: Andexanet alfa shows promise to become a highly effective, novel antidote for factor Xa anticoagulation. Its biochemical profile and mechanism of action are immediately more attractive than other drugs on the market and under development due to its inert nature within the normal coagulation cascade, with minimal intrinsic procoagulant or anticoagulant properties. The anticoagulant antidote space will continue to develop as more specific and universal options become available for reversal of the effect of DOACs. Preliminary results of a pivotal phase 3b/4 trial demonstrate a favorable efficacy and safety profile in patients with acute hemorrhage.

ASSERT trial - How to assess the safety and efficacy of a high frequency rTMS in postpartum depression ? A multicenter, double blinded, randomized, placebo-controlled clinical trial

Background

Postpartum Depression affects a considerable number of women worldwide. This condition inflicts severe consequences to mother and child health. Thus far, available treatments have low response and high relapse rates. We designed this trial to evaluate a safe and more efficacious innovative therapy.

Aims

To report a feasible and ethical study design to assess the safety and efficacy of a high frequency repetitive Transcranial Magnetic Stimulation 10 Hz (rTMS) compared to sham rTMS in women with moderate to severe Post-Partum Depression using standard treatment (sertraline).

To conduct an ancillary, exploratory, randomized, active controlled, double blind study with a hypothesis to assess the safety and efficacy of 10 Hz rTMS compared to sertraline.

Methods

A multicenter, parallel arm, randomized, placebo-controlled, double-blind design to assess safety and efficacy of 10 Hz rTMS compared to sham.

An ancillary study will be conducted with parallel arm, randomized, active controlled and double dummy design to assess safety and efficacy of 10 Hz rTMS compared to sertraline.