Standardized Data Elements for Patients With Acute Pulmonary Embolism: A Consensus Report from the Pulmonary Embolism Research Collaborative.

Recent advances in therapy and the promulgation of multidisciplinary pulmonary embolism teams show great promise to improve management and outcomes of acute pulmonary embolism (PE). However, the absence of randomized evidence and lack of consensus leads to tremendous variations in treatment and compromises the wide implementation of new innovations. Moreover, the changing landscape of health care, where quality, cost, and accountability are increasingly relevant, dictates that a broad spectrum of outcomes of care must be routinely monitored to fully capture the impact of modern PE treatment. We set out to standardize data collection in patients with PE undergoing evaluation and treatment, and thus establish the foundation for an expanding evidence base that will address gaps in evidence and inform future care for acute PE. To do so, >100 international PE thought leaders convened in Washington, DC, in April 2022 to form the Pulmonary Embolism Research Collaborative. Participants included physician experts, key members of the US Food and Drug Administration, patient representatives, and industry leaders. Recognizing the multidisciplinary nature of PE care, the Pulmonary Embolism Research Collaborative was created with representative experts from stakeholder medical subspecialties, including cardiology, pulmonology, vascular medicine, critical care, hematology, cardiac surgery, emergency medicine, hospital medicine, and pharmacology. A list of critical evidence gaps was composed with a matching comprehensive set of standardized data elements; these data points will provide a foundation for productive research, knowledge enhancement, and advancement of clinical care within the field of acute PE, and contribute to answering urgent unmet needs in PE management. Evidence produced through the Pulmonary Embolism Research Collaborative, as it is applied to data collection, promises to provide crucial knowledge that will ultimately produce a robust evidence base that will lead to standardization and harmonization of PE management and improved outcomes.

Mechanical Thrombectomy for High-Risk Pulmonary Embolism: Insights From the US Cohort of the FLASH Registry.

Background: Acute mortality for high-risk, or massive, pulmonary embolism (PE) is almost 30% even when treated using advanced therapies. This analysis assessed the safety and effectiveness of mechanical thrombectomy (MT) for high-risk PE. Methods: The prospective, multicenter FlowTriever All-comer Registry for Patient Safety and Hemodynamics (FLASH) study is designed to evaluate real-world PE patient outcomes after MT with the FlowTriever System (Inari Medical). In this study, acute outcomes through 30 days were evaluated for the subset of patients with high-risk PE as determined by the sites and following European Society of Cardiology guidelines. An independent medical monitor adjudicated adverse events (AEs), including major AEs: device-related mortality, major bleeding, or intraprocedural device-related or procedure-related AEs. Results: Of the 799 patients in the US cohort, 63 (7.9%) were diagnosed with high-risk PE; 30 (47.6%) patients showed a systolic blood pressure <90 mm Hg, 29 (46.0%) required vasopressors, and 4 (6.3%) experienced cardiac arrest. The mean age of patients with high-risk PE was 59.4 ± 15.6 years, and 34 (54.0%) were women. At baseline, 45 (72.6%) patients were tachycardic, 18 (54.5%) showed elevated lactate levels of ≥2.5 mM, and 21 (42.9%) demonstrated depressed cardiac index of <2 L/min/m2. Immediately after MT, heart rate improved to 93.5 ± 17.9 bpm. Twenty-five (42.4%) patients did not require an overnight stay in the intensive care unit, and no mortalities or major AEs occurred through 48 hours. Moreover, no mortalities occurred in 61 (96.8%) patients followed up through the 30-day visit. Conclusions: In this cohort of 63 patients with high-risk PE, MT was safe and effective, with no acute mortalities reported. Further prospective data are needed in this population.

Venoarterial extracorporeal membrane oxygenation in high-risk pulmonary embolism: A narrative review.

Emergent reperfusion, most commonly with the administration of thrombolytic agents, is the recommended management approach for patients presenting with high-risk, or hemodynamically unstable pulmonary embolism. However, a subset of patients with a more catastrophic presentation, including refractory shock and impending or active cardiopulmonary arrest, may require immediate circulatory support. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) can be deployed rapidly by the well-trained team and provide systemic perfusion allowing for hemodynamic stabilization. Subsequent embolectomy or a standalone strategy allowing for thrombus autolysis may be followed with decannulation after several days. Retrospective studies and registry data suggest favorable clinical outcomes with the use of VA-ECMO as an upfront stabilization strategy even among patients presenting with cardiopulmonary arrest. In this review, we discuss the physiologic rationale, evidence base, and an approach to ECMO deployment and subsequent management strategies among select patients with high-risk pulmonary embolism.

Composite Pulmonary Embolism Shock Score and Risk of Adverse Outcomes in Patients With Pulmonary Embolism.

BACKGROUND: In hemodynamically stable patients with acute pulmonary embolism (PE), the Composite Pulmonary Embolism Shock (CPES) score predicts normotensive shock. However, it is unknown if CPES predicts adverse clinical outcomes. The objective of this study was to determine whether the CPES score predicts in-hospital mortality, resuscitated cardiac arrest, or hemodynamic deterioration. METHODS: Patients with acute intermediate-risk PE admitted from October 2016 to July 2019 were included. CPES was calculated for each patient. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation. Secondary outcomes included individual components of the primary outcome. The association of CPES with primary and secondary outcomes was evaluated. RESULTS: Among the 207 patients with intermediate-risk PE (64.7% with intermediate-high risk PE), 29 (14%) patients had a primary outcome event. In a multivariable model, a higher CPES score was associated with a worse primary composite outcome (adjusted hazard ratio [aHR], 1.81 [95% CI, 1.29-2.54]; P=0.001). Moreover, a higher CPES score predicted death (aHR, 1.76 [95% CI, 1.04-2.96]; P=0.033), resuscitated cardiac arrest (aHR, 1.99 [95% CI, 1.17-3.38]; P=0.011), and hemodynamic decompensation (aHR, 1.96 [95% CI, 1.34-2.89]; P=0.001). A high CPES score (≥3) was associated with the worse primary outcome when compared with patients with a low CPES score (22% versus 2.4%; P=0.003; aHR, 6.48 [95% CI, 1.49-28.04]; P=0.012). CPES score provided incremental prognostic value for the prediction of primary outcome over baseline demographics and European Society of Cardiology intermediate-risk subcategories (global Χ2 value increased from 0.63 to 1.39 to 13.69; P=0.005). CONCLUSIONS: In patients with acute intermediate-risk PE, the CPES score effectively risk stratifies and prognosticates patients for the prediction of clinical events and provides incremental value over baseline demographics and European Society of Cardiology intermediate-risk subcategories.

McConnell's sign predicts normotensive shock in patients with acute pulmonary embolism.

BACKGROUND: Patients with intermediate-risk pulmonary embolism (PE) and normotensive shock may have worse outcomes. However, diagnosis of normotensive shock requires invasive hemodynamics. Our objective was to assess the predictive value of McConnell's sign in identifying normotensive shock in patients with intermediate-risk PE. METHODS: Patients with intermediate-risk PE who underwent percutaneous mechanical thrombectomy between August 2020 and April 2023 at a large academic public hospital were included in the study. Normotensive shock was defined as systolic blood pressure ≥ 90 mmHg without vasopressor support with pre-procedural invasive measures of cardiac index ≤2.2 L/min/m2 and clinical evidence of hypoperfusion (i.e. elevated lactate, oliguria). The primary outcome was the association between McConnell's sign and normotensive shock. RESULTS: Those with McConnell's sign (29/40, 72.5 %) had higher heart rate (114 vs 99 beats/min, p = 0.008), higher rates of elevated lactate (86 % vs 55 %, p = 0.038), lower cardiac index (1.9 vs 3.1 L/min/m2, p = 0.003), and higher rates of normotensive shock (76 % vs 27 %, p = 0.005). McConnell's sign had a sensitivity of 88 % and specificity of 53 % for identifying intermediate-risk PE patients with normotensive shock. Patients with McConnell's sign had an increased odds (odds ratio 8.38, confidence interval: 1.73-40.53, p = 0.008; area under the curve 0.70, 95 % confidence interval: 0.56-0.85) of normotensive shock. CONCLUSION: This is the first study to suggest that McConnell's sign may identify those in the intermediate-risk group who are at risk for normotensive shock. Larger cohorts are needed to validate our findings.

Comparing Management Strategies in Patients With Clot-in-Transit.

BACKGROUND: Clot-in-transit is associated with high mortality, but optimal management strategies remain uncertain. The aim of this study was to compare the outcomes of different treatment strategies in patients with clot-in-transit. METHODS: This is a retrospective study of patients with documented clot-in-transit in the right heart on echocardiography across 2 institutions between January 2020 and October 2023. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation. RESULTS: Among 35 patients included in the study, 10 patients (28.6%) received anticoagulation alone and 2 patients (5.7%) received systemic thrombolysis, while 23 patients (65.7%) underwent catheter-based therapy (CBT; 22 mechanical thrombectomy and 1 catheter-directed thrombolysis). Over a median follow-up of 30 days, 9 patients (25.7%) experienced the primary composite outcome. Compared with anticoagulation alone, patients who received CBT or systemic thrombolysis had significantly lower rates of the primary composite outcome (12% versus 60%; log-rank P<0.001; hazard ratio, 0.13 [95% CI, 0.03-0.54]; P=0.005) including a lower rate of death (8% versus 50%; hazard ratio, 0.10 [95% CI, 0.02-0.55]; P=0.008), resuscitated cardiac arrest (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P=0.067), or hemodynamic deterioration (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P=0.067). CONCLUSIONS: In this study of CBT in patients with clot-in-transit, CBT or systemic thrombolysis was associated with a significantly lower rate of adverse clinical outcomes, including a lower rate of death compared with anticoagulation alone driven by the CBT group. CBT has the potential to improve outcomes. Further large-scale studies are needed to test these associations.

Evaluating the hemodynamic impact of saddle versus non-saddle pulmonary embolism: insights from a thrombectomy cohort.

Objectives: The aim of this study was to compare the hemodynamic impact and clinical outcomes of saddle vs non-saddle pulmonary embolism (PE). Methods: This was a retrospective analysis of clinical characteristics and outcomes among patients with saddle and non-saddle PE within a cohort referred for catheter-based thrombectomy (CBT) with invasive hemodynamic assessments. Patients who underwent CBT between August 2020 and January 2024 were included. The primary outcome was the proportion of patients with a low cardiac index (CI < 2.2 L/min/m²). Secondary outcomes included 30-day mortality, intensive care unit (ICU) length of stay (LOS), and hospital LOS. Results: A total of 107 patients (84 intermediate risk, 23 high-risk; mean age 58 years, 47.6% female) were included in the study, with 44 patients having saddle PE and 63 having non-saddle PE. There were no significant differences in baseline demographics and clinical characteristics between saddle and non-saddle PE, including rates of high-risk PE (25% vs 16%, P = .24), rates of RV dysfunction, pulmonary artery systolic pressure (55 vs 53 mm Hg, P = .74), mean pulmonary artery pressure (34 mm Hg vs 33 mm Hg), low cardiac index (56% vs 51%, P = .64), rates of normotensive shock (27% vs 20%, P = .44), or Composite Pulmonary Embolism Shock scores (4.5 vs 4.7, P = .25). Additionally, 30-day mortality (6% vs 5%, P = .69), ICU LOS, and hospital LOS were similar between the groups. Conclusions: Among patients undergoing CBT, there were no significant differences in invasive hemodynamic parameters or clinical outcomes between those with saddle and non-saddle PE.

Low left ventricular outflow tract velocity time integral predicts normotensive shock in patients with acute pulmonary embolism.

In this study, we found that a low LVOT VTI (<15 cm), a simple bedside point-of-care measurement, predicts normotensive shock in patients with acute intermediate-risk PE.

Catheter-based therapy for high-risk or intermediate-risk pulmonary embolism: death and re-hospitalization.

BACKGROUND AND AIMS: Catheter-based therapies (CBTs) have been developed as a treatment option in patients with pulmonary embolism (PE). There remains a paucity of data to inform decision-making in patients with intermediate-risk or high-risk PE. The aim of this study was to characterize in-hospital and readmission outcomes in patients with intermediate-risk or high-risk PE treated with vs. without CBT in a large retrospective registry. METHODS: Patients hospitalized with intermediate-risk or high-risk PE were identified using the 2017-20 National Readmission Database. In-hospital outcomes included death and bleeding and 30- and 90-day readmission outcomes including all-cause, venous thromboembolism (VTE)-related and bleeding-related readmissions. Inverse probability of treatment weighting (IPTW) was utilized to compare outcomes between CBT and no CBT. RESULTS: A total of 14 903 [2076 (13.9%) with CBT] and 42 829 [8824 (20.6%) with CBT] patients with high-risk and intermediate-risk PE were included, respectively. Prior to IPTW, patients with CBT were younger and less likely to have cancer and cardiac arrest, receive systemic thrombolysis, or be on mechanical ventilation. In the IPTW logistic regression model, CBT was associated with lower odds of in-hospital death in high-risk [odds ratio (OR) 0.83, 95% confidence interval (CI) 0.80-0.87] and intermediate-risk PE (OR 0.76, 95% CI 0.70-0.83). Patients with high-risk PE treated with CBT were associated with lower risk of 90-day all-cause [hazard ratio (HR) 0.77, 95% CI 0.71-0.83] and VTE (HR 0.46, 95% CI 0.34-0.63) readmission. Patients with intermediate-risk PE treated with CBT were associated with lower risk of 90-day all-cause (HR 0.75, 95% CI 0.72-0.79) and VTE (HR 0.66, 95% CI 0.57-0.76) readmission. CONCLUSIONS: Among patients with high-risk or intermediate-risk PE, CBT was associated with lower in-hospital death and 90-day readmission. Prospective, randomized trials are needed to confirm these findings.

Evaluating the Use of Unfractionated Heparin with Intra-Aortic Balloon Counterpulsation.

BACKGROUND: Evidence supporting anticoagulation with unfractionated heparin (UFH) in patients with an intra-aortic balloon pump (IABP) to prevent limb ischaemia remains limited, while bleeding risks remain high. Monitoring heparin in this setting with anti-factor Xa (anti-Xa) is not previously described. OBJECTIVES: The study objective is to describe the incidence of thromboembolic and bleeding events with the use of UFH in patients with an IABP utilising monitoring with both anti-Xa and activated partial thromboplastin time (aPTT). METHODS: This is a retrospective study of adults who received an IABP and UFH for ≥24 hours. Electronic medical records were reviewed for pertinent data. The primary outcome was the incidence of limb ischaemia during IABP. Secondary outcomes included myocardial infarction, thrombus on IABP, or stroke. Exploratory outcomes included any venous thromboembolism and bleeding events. RESULTS: Of 159 patients, 88% received an IABP for cardiogenic shock and median duration of IABP support was 118 hours (interquartile range, 67-196). Limb ischaemia occurred in four of 159 patients (2.5%). Strokes occurred in 3.8% of the cohort, and bleeding events occurred in 33%. Despite anticoagulation use in all patients, 11% experienced a venous thromboembolism, with most identified upon asymptomatic screening with concern for heparin-induced thrombocytopenia. We found no differences in outcomes that occurred with a hybrid anti-Xa and aPTT versus aPTT monitoring alone. CONCLUSIONS: We observed a high rate of thrombotic and bleeding complications with the use of UFH in patients with an IABP. Use of anti-Xa versus aPTT for monitoring was not associated with complications. These data suggest safer anticoagulation strategies are needed in this setting.

Percutaneous mechanical thrombectomy in acute pulmonary embolism: Outcomes from a safety-net hospital.

BACKGROUND: Our study aims to present clinical outcomes of mechanical thrombectomy (MT) in a safety-net hospital. METHODS: This is a retrospective study of intermediate or high-risk pulmonary embolism (PE) patients who underwent MT between October 2020 and May 2023. The primary outcome was 30-day mortality. RESULTS: Among 61 patients (mean age 57.6 years, 47% women, 57% Black) analyzed, 12 (19.7%) were classified as high-risk PE, and 49 (80.3%) were intermediate-risk PE. Of these patients, 62.3% had Medicaid or were uninsured, 50.8% lived in a high poverty zip code. The prevalence of normotensive shock in intermediate-risk PE patients was 62%. Immediate hemodynamic improvements included 7.4 mmHg mean drop in mean pulmonary artery pressure (-21.7%, p < 0.001) and 93% had normalization of their cardiac index postprocedure. Thirty-day mortality for the entire cohort was 5% (3 patients) and 0% when restricted to the intermediate-risk group. All 3 patients who died at 30 days presented with cardiac arrest. There were no differences in short-term mortality based on race, insurance type, citizenship status, or socioeconomic status. All-cause mortality at most recent follow up was 13.1% (mean follow up time of 13.4 ± 8.5 months). CONCLUSION: We extend the findings from prior studies that MT demonstrates a favorable safety profile with immediate improvement in hemodynamics and a low 30-day mortality in patients with acute PE, holding true even with relatively higher risk and more vulnerable population within a safety-net hospital.

Development and external validation of a dynamic risk score for early prediction of cardiogenic shock in cardiac intensive care units using machine learning.

AIMS: Myocardial infarction and heart failure are major cardiovascular diseases that affect millions of people in the USA with morbidity and mortality being highest among patients who develop cardiogenic shock. Early recognition of cardiogenic shock allows prompt implementation of treatment measures. Our objective is to develop a new dynamic risk score, called CShock, to improve early detection of cardiogenic shock in the cardiac intensive care unit (ICU). METHODS AND RESULTS: We developed and externally validated a deep learning-based risk stratification tool, called CShock, for patients admitted into the cardiac ICU with acute decompensated heart failure and/or myocardial infarction to predict the onset of cardiogenic shock. We prepared a cardiac ICU dataset using the Medical Information Mart for Intensive Care-III database by annotating with physician-adjudicated outcomes. This dataset which consisted of 1500 patients with 204 having cardiogenic/mixed shock was then used to train CShock. The features used to train the model for CShock included patient demographics, cardiac ICU admission diagnoses, routinely measured laboratory values and vital signs, and relevant features manually extracted from echocardiogram and left heart catheterization reports. We externally validated the risk model on the New York University (NYU) Langone Health cardiac ICU database which was also annotated with physician-adjudicated outcomes. The external validation cohort consisted of 131 patients with 25 patients experiencing cardiogenic/mixed shock. CShock achieved an area under the receiver operator characteristic curve (AUROC) of 0.821 (95% CI 0.792-0.850). CShock was externally validated in the more contemporary NYU cohort and achieved an AUROC of 0.800 (95% CI 0.717-0.884), demonstrating its generalizability in other cardiac ICUs. Having an elevated heart rate is most predictive of cardiogenic shock development based on Shapley values. The other top 10 predictors are having an admission diagnosis of myocardial infarction with ST-segment elevation, having an admission diagnosis of acute decompensated heart failure, Braden Scale, Glasgow Coma Scale, blood urea nitrogen, systolic blood pressure, serum chloride, serum sodium, and arterial blood pH. CONCLUSION: The novel CShock score has the potential to provide automated detection and early warning for cardiogenic shock and improve the outcomes for millions of patients who suffer from myocardial infarction and heart failure.

Relationship between the mixed venous-to-arterial carbon dioxide gradient and the cardiac index in acute pulmonary embolism.

AIMS: Among patients with acute pulmonary embolism (PE) undergoing mechanical thrombectomy, the cardiac index (CI) is frequently reduced even among those without a clinically apparent shock. The purpose of this study is to describe the mixed venous-to-arterial carbon dioxide gradient (CO2 gap), a surrogate of perfusion adequacy, among patients with acute PE undergoing mechanical thrombectomy. METHODS AND RESULTS: This was a single-centre retrospective study of consecutive patients with PE undergoing mechanical thrombectomy and simultaneous pulmonary artery catheterization over a 3-year period. Of 107 patients, 97 had simultaneous mixed venous and arterial blood gas measurements available. The CO2 gap was elevated (>6 mmHg) in 51% of the cohort and in 49% of patients with intermediate-risk PE. A reduced CI (≤2.2 L/min/m2) was associated with an increased odds [odds ratio = 7.9; 95% confidence interval (CI) 3.49-18.1, P < 0.001] for an elevated CO2 gap. There was an inverse relationship between the CI and the CO2 gap. For every 1 L/min/m2 decrease in the CI, the CO2 gap increased by 1.3 mmHg (P = 0.001). Among patients with an elevated baseline CO2 gap >6 mmHg, thrombectomy improved the CO2 gap, CI, and mixed venous oxygen saturation. When the CO2 gap was dichotomized above and below 6, there was no difference in the in-hospital mortality rate (9 vs. 0%; P = 0.10; hazard ratio: 1.24; 95% CI 0.97-1.60; P = 0.085). CONCLUSION: Among patients with acute PE undergoing mechanical thrombectomy, the CO2 gap is abnormal in nearly 50% of patients and inversely related to the CI. Further studies should examine the relationship between markers of perfusion and outcomes in this population to refine risk stratification.

Need for a Cardiogenic Shock Team Collaborative-Promoting a Team-Based Model of Care to Improve Outcomes and Identify Best Practices.

Cardiogenic shock continues to carry a high mortality rate despite contemporary care, with no breakthrough therapies shown to improve survival over the past few decades. It is a time-sensitive condition that commonly results in cardiovascular complications and multisystem organ failure, necessitating multidisciplinary expertise. Managing patients with cardiogenic shock remains challenging even in well-resourced settings, and an important subgroup of patients may require cardiac replacement therapy. As a result, the idea of leveraging the collective cognitive and procedural proficiencies of multiple providers in a collaborative, team-based approach to care (the "shock team") has been advocated by professional societies and implemented at select high-volume clinical centers. A slowly maturing evidence base has suggested that cardiogenic shock teams may improve patient outcomes. Although several registries exist that are beginning to inform care, particularly around therapeutic strategies of pharmacologic and mechanical circulatory support, none of these are currently focused on the shock team approach, multispecialty partnership, education, or process improvement. We propose the creation of a Cardiogenic Shock Team Collaborative-akin to the successful Pulmonary Embolism Response Team Consortium-with a goal to promote sharing of care protocols, education of stakeholders, and discovery of how process and performance may influence patient outcomes, quality, resource consumption, and costs of care.

Prognostic performance of the IABP-SHOCK II Risk Score among cardiogenic shock subtypes in the critical care cardiology trials network registry.

BACKGROUND: Risk stratification has potential to guide triage and decision-making in cardiogenic shock (CS). We assessed the prognostic performance of the IABP-SHOCK II score, derived in Europe for acute myocardial infarct-related CS (AMI-CS), in a contemporary North American cohort, including different CS phenotypes. METHODS: The critical care cardiology trials network (CCCTN) coordinated by the TIMI study group is a multicenter network of cardiac intensive care units (CICU). Participating centers annually contribute ≥2 months of consecutive medical CICU admissions. The IABP-SHOCK II risk score includes age > 73 years, prior stroke, admission glucose > 191 mg/dl, creatinine > 1.5 mg/dl, lactate > 5 mmol/l, and post-PCI TIMI flow grade < 3. We assessed the risk score across various CS etiologies. RESULTS: Of 17,852 medical CICU admissions 5,340 patients across 35 sites were admitted with CS. In patients with AMI-CS (n = 912), the IABP-SHOCK II score predicted a >3-fold gradient in in-hospital mortality (low risk = 26.5%, intermediate risk = 52.2%, high risk = 77.5%, P < .0001; c-statistic = 0.67; Hosmer-Lemeshow P = .79). The score showed a similar gradient of in-hospital mortality in patients with non-AMI-related CS (n = 2,517, P < .0001) and mixed shock (n = 923, P < .001), as well as in left ventricular (<0.0001), right ventricular (P = .0163) or biventricular (<0.0001) CS. The correlation between the IABP-SHOCK II score and SOFA was moderate (r2 = 0.17) and the IABP-SHOCK II score revealed a significant risk gradient within each SCAI stage. CONCLUSIONS: In an unselected international multicenter registry of patients admitted with CS, the IABP- SHOCK II score only moderately predicted in-hospital mortality in a broad population of CS regardless of etiology or irrespective of right, left, or bi-ventricular involvement.

Catheter-based therapy for intermediate or high-risk pulmonary embolism is associated with lower in-hospital mortality in patients with cancer: Insights from the National Inpatient Sample.

BACKGROUND: Pulmonary embolism (PE) is a common complication among patients with cancer and is a significant contributor to morbidity and mortality. Catheter-based therapies (CBT), including catheter-directed thrombolysis (CDT) and mechanical thrombectomy, have been developed and are used in patients with intermediate or high-risk PE. However, there is a paucity of data on outcomes in patients with cancer as most clinical studies exclude this group of patients. AIMS: To characterize outcomes of patients with cancer admitted with intermediate or high-risk PE treated with CBT compared with no CBT. METHODS: Patients with an admission diagnosis of intermediate or high-risk PE and a history of cancer from October 2015 to December 2018 were identified using the National Inpatient Sample. Outcomes of interest were in-hospital death or cardiac arrest (CA) and major bleeding. Inverse probability treatment weighting (IPTW) was utilized to compare outcomes between patients treated with and without CBT. Variables that remained unbalanced after IPTW were adjusted using multivariable logistic regression. RESULTS: A total of 2084 unweighted admissions (10,420 weighted) for intermediate or high-risk PE and cancer were included, of which 136 (6.5%) were treated with CBT. After IPTW, CBT was associated with lower death or CA (aOR 0.54, 95% CI 0.46-0.64) but higher major bleeding (aOR 1.41, 95% CI 1.21-1.65). After stratifying by PE risk type, patients treated with CBT had lower risk of death or CA in both intermediate (aOR 0.52, 95% CI 0.36-0.75) and high-risk PE (aOR 0.48, 95% CI 0.33-0.53). However, patients with CBT were associated with increased risk of major bleeding in intermediate-risk PE (aOR 2.12, 95% CI 1.67-2.69) but not in those with high-risk PE (aOR 0.84, 95% CI 0.66-1.07). CONCLUSIONS: Among patients with cancer hospitalized with intermediate or high-risk PE, treatment with CBT was associated with lower risk of in-hospital death or CA but higher risk of bleeding. Prospective studies and inclusion of patients with cancer in randomized trials are warranted to confirm our findings.

Anti-factor Xa as the preferred assay to monitor heparin for the treatment of pulmonary embolism.

INTRODUCTION: The mainstay of acute pulmonary embolism (PE) treatment is anticoagulation. Timely anticoagulation correlates with decreased PE-associated mortality, but the ability to achieve a therapeutic activated partial thromboplastin time (aPTT) with unfractionated heparin (UFH) remains limited. Although some institutions have switched to a more accurate and reproducible test to assess for heparin's effectiveness, the anti-factor Xa (antiXa) assay, data correlating a timely therapeutic antiXa to PE-associated clinical outcomes remains scarce. We evaluated time to a therapeutic antiXa using intravenous heparin after PE response team (PERT) activation and assessed clinical outcomes including bleeding and recurrent thromboembolic events. METHODS: This was a retrospective cohort study at NYU Langone Health. All adult patients ≥18 years with a confirmed PE started on IV UFH with >2 antiXa levels were included. Patients were excluded if they received thrombolysis or alternative anticoagulation. The primary endpoint was the time to a therapeutic antiXa level of 0.3-0.7 units/mL. Secondary outcomes included recurrent thromboembolism, bleeding and PE-associated mortality within 3 months. RESULTS: A total of 330 patients with a PERT consult were identified with 192 patients included. The majority of PEs were classified as sub massive (64.6%) with 87% of patients receiving a bolus of 80 units/kg of UFH prior to starting an infusion at 18 units/kg/hour. The median time to the first therapeutic antiXa was 9.13 hours with 93% of the cohort sustaining therapeutic anticoagulation at 48 hours. Recurrent thromboembolism, bleeding and mortality occurred in 1%, 5% and 6.2%, respectively. Upon univariate analysis, a first antiXa <0.3 units/ml was associated with an increased risk of mortality [27.78% (5/18) vs 8.05% (14/174), p = 0.021]. CONCLUSION: We observed a low incidence of recurrent thromboembolism or PE-associated mortality utilizing an antiXa titrated UFH protocol. The use of an antiXa based heparin assay to guide heparin dosing and monitoring allows for timely and sustained therapeutic anticoagulation for treatment of PE.