Faculty Bibliography

BACKGROUND AND AIMS/OBJECTIVE:Patients with intermediate-risk pulmonary embolism (PE) commonly present with a significantly reduced cardiac index (CI). However, the identification of this more severe profile requires invasive hemodynamic monitoring. Whether inferior vena cava (IVC) contrast reflux, as a marker of worse right ventricular function, can predict invasive hemodynamics has not been explored. METHODS:This was a single-center retrospective study over a 3-year period of consecutive patients with PE undergoing mechanical thrombectomy and simultaneous pulmonary artery catheterization. CT pulmonary angiograms were reviewed, and contrast reflux was graded as no/minimal reflux (limited to the IVC) or substantial (opacification including hepatic veins) based on an established scale. RESULTS:were 62.6 %, 93.1 %, 94.6 %, and 56.2 %, respectively. These findings remained significant in a multivariable model and were similar when isolating for intermediate-risk patients (n = 72, 85 %). CONCLUSIONS:The degree of contrast reflux is highly specific for a reduced cardiac index in PE even when isolating for intermediate-risk patients. Real-time prediction of a hemodynamic profile may have added value in the risk-stratification of PE.

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.

BACKGROUND/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED:=0.005). CONCLUSIONS/UNASSIGNED: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.

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/OBJECTIVE: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.

BACKGROUND:Myocardial infarction and heart failure are major cardiovascular diseases that affect millions of people in the US with the 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 cardiac intensive care unit (ICU). METHODS: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 onset of cardiogenic shock. We prepared a cardiac ICU dataset using MIMIC-III database by annotating with physician adjudicated outcomes. This dataset that 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 that was also annotated with physician adjudicated outcomes. The external validation cohort consisted of 131 patients with 25 patients experiencing cardiogenic/mixed shock. RESULTS: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 ten 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. CONCLUSIONS:The novel CShock score has the potential to provide automated detection and early warning for cardiogenic shock and improve the outcomes for the millions of patients who suffer from myocardial infarction and heart failure.

AIMS/OBJECTIVE: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/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/CONCLUSIONS: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.

BACKGROUND AND AIMS/OBJECTIVE: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.

BACKGROUND/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED:=0.067). CONCLUSIONS/UNASSIGNED: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.

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.