Faculty Bibliography

Acute respiratory distress syndrome (ARDS) is a heterogeneous group of disease entities that are associated with acute hypoxic respiratory failure and significant morbidity and mortality. With a better understanding and phenotyping of lung injury, novel pathophysiologic mechanisms demonstrate the impact of a patient's excessive spontaneous breathing effort on perpetuating lung injury. Patient self-inflicted lung injury (P-SILI) is a recently identified phenomenon that delves into the impact of spontaneous breathing on respiratory mechanics in patients with lung injury. While the studies are hypothesis-generating and have been demonstrated in animal and human studies, further clinical trials are needed to identify its impact on ARDS management. The purpose of this review article is to highlight the physiologic mechanisms of P-SILI, novel tools and methods to detect P-SILI, and to review the current literature on non-invasive and invasive respiratory management in patients with ARDS.

BACKGROUND:The relationship between syncope and invasive hemodynamics in patients with pulmonary embolism (PE) remains unknown. The objective of this study was to assess the ability of syncope, as a single clinical variable, to predict a low cardiac index in patients with acute PE. METHODS:) in patients with acute intermediate- high risk PE. Secondary outcomes included 30-day mortality, hemodynamic instability, 90-day readmission rates, other invasive hemodynamic parameters, intensive care unit (ICU) length of stay (LOS), and hospital LOS. Regression analyses were used to evaluate the association between cardiac index and syncope. RESULTS:A total of 132 patients (86% intermediate- and 14% high-risk) were included in the study, with 27 (20%) presenting with syncope. Among the 114 intermediate-risk patients, 24 (21%) presented with syncope. In all-comers, there was no significant difference between groups at baseline. Within the intermediate-only subgroup, there were no significant differences between groups at baseline, except that the syncope group was older (62.6 ± 14.9 vs. 56.1 ± 13.9, p=0.048, Table 2) and had significantly higher troponin elevation at presentation (684.3 ± 1361.8ng/L vs. 195.6 ± 278.1ng/L, p=0.003, Table 2). In all-comers, there was no difference in rates of low cardiac index (63% vs. 59%, p=0.71) or mPAP (33.9 ± 8.6 vs. 32.7 ± 9.6 mm Hg, p=0.57) between patients who presented with and without syncope. Similarly, among intermediate-risk patients, there was also no difference in the rates of low cardiac index (67% vs. 57%, p=0.38) or mPAP (34.0 ± 9.2 vs. 33.1 ± 9.8 mmHg, p=0.69) between patients with and without syncope. There was no difference in clinical outcomes between those who presented with and without syncope. CONCLUSION/CONCLUSIONS:In conclusion, in patients with acute PE, syncope was not associated with a low cardiac index or higher mPAP.

BACKGROUND/UNASSIGNED:The aim of this study was to examine the impact of early versus delayed catheter-based therapies (CBTs) on clinical outcomes in patients with acute intermediate-risk pulmonary embolism (PE). METHODS/UNASSIGNED:This retrospective cohort study analyzed data from 2 academic centers involving patients with intermediate-risk PE from January 2020 to January 2024. Patients were divided into early (<12 hours) and delayed CBT (≥12 hours) groups. The primary outcome was a composite of 30-day mortality, resuscitated cardiac arrest, hemodynamic instability, and 90-day readmission. Secondary outcomes included a composite of 30-day mortality, resuscitated cardiac arrest, and hemodynamic instability. Inverse probability of treatment weighting was used to balance covariates. RESULTS/UNASSIGNED:=0.046). When patients were stratified by timing of CBT (early/late) and the composite PE shock score (high ≥3; low <3), all 16 patients who experienced the primary composite outcome had a high composite PE shock score, with 14/16 (87.5%) having a high composite PE shock score and delayed intervention. CONCLUSIONS/UNASSIGNED:Early CBT was associated with improved clinical outcomes in patients with acute intermediate-risk PE. The composite PE shock score may help identify patients who will benefit from early CBT. Further prospective studies are needed to validate these findings.

BACKGROUND:The recently published PEERLESS trial compared catheter-directed thrombolysis (CDT) and catheter-based thrombectomy (CBT) in acute pulmonary embolism (PE). However, it included a low proportion of patients with contraindications to thrombolytic therapy (4.4%), leaving uncertainty about how CDT would perform relative to CBT in a real-world cohort with higher bleeding risk. AIMS/OBJECTIVE:This study aims to address this gap by comparing real-world outcomes of CDT and CBT in patients with acute PE. METHODS:This retrospective analysis included patients who underwent CDT and CBT at two tertiary care centers from January 2020 to January 2024. The primary outcome was a composite of 30-day mortality, resuscitated cardiac arrest, or hemodynamic decompensation. Secondary outcomes included major bleeding and intracranial hemorrhage (ICH). Inverse probability treatment weighting (IPTW) was used to adjust for baseline variables. RESULTS:A total of 162 (mean age 58 years, 45.7% women, 17.3% high-risk, 28% contraindication to lytics, 28% CDT, 72% CBT) patients were included, with 12.4% patients experiencing the primary outcome. There was no difference in the rates of the primary outcome between CBT versus CDT (11.2% vs. 15.2%, IPTW HR: 0.80; 95% CI: 0.27-2.38, p = 0.69). CBT was associated with a lower risk of hemodynamic decompensation (5% vs. 21.7%, p = 0.036), major bleeding (7.8% vs. 17.4%, IPTW HR 0.26; 95% CI: 0.07-0.95, p = 0.042) and ICH (0 vs. 4.3%, p = 0.024) compared to CDT. CONCLUSION/CONCLUSIONS:Among a real-world cohort of patients with acute PE with higher bleeding risk than PEERLESS undergoing catheter-based therapies, CBT was associated with a lower rate of hemodynamic deterioration, major bleeding, and ICH with similar rate of primary composite outcome when compared with CDT. Additional randomized controlled trials are needed to validate these findings.

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.

Right ventricular-pulmonary arterial coupling describes the relation between right ventricular contractility and its afterload and is estimated as the ratio of the tricuspid annular plane systolic excursion (TAPSE) to pulmonary arterial systolic pressure (PASP) by way of echocardiography. Whether TAPSE/PASP is reflective of invasive hemodynamics or occult shock in acute pulmonary embolism (PE) is unknown. This was a single-center retrospective study over a 3-year period of consecutive patients with PE who underwent mechanical thrombectomy and simultaneous pulmonary artery catheterization with echocardiograms performed within 24 hours before the procedure. A total of 70 patients (81% intermediate risk) had complete invasive hemodynamic profiles and echocardiograms, with TAPSE/PASP calculated. The optimal cutoff for TAPSE/PASP as a predictor of a reduced cardiac index (CI) (CI ≤2.2 L/min/m²) was 0.34 mm/mm Hg, with an area under the curve of 0.97 and sensitivity, specificity, positive predictive value, and negative predictive value of 97.3%, 90.9%, 92.3%, and 96.8%, respectively. Every 0.1 mm/mm Hg decrease in TAPSE/PASP was associated with a 0.24-L/min/m² decrease in the CI. This relation was similar when restricted to intermediate-risk PE. The TAPSE/PASP ratio was predictive of normotensive shock with an odds ratio of 2.63 (95% confidence interval 1.42 to 4.76, p = 0.002) per unit decrease in the ratio. In conclusion, in patients with acute PE who underwent mechanical thrombectomy, TAPSE/PASP was a strong predictor of a reduced CI and normotensive shock. This means that noninvasive point-of-care assessment of hemodynamics may have added value in PE risk stratification.

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.

INTRODUCTION/BACKGROUND:This study explores the implementation and outcomes of catheter-based thrombectomy (CBT) for acute pulmonary embolism (PE) within a safety-net hospital (SNH), addressing a critical gap in the literature concerning CBT in underserved and vulnerable populations. METHODS:This is a retrospective study of patients undergoing CBT between October 2020 and January 2024 at a SNH. The primary outcome was 30-day all-cause mortality. RESULTS:A total of 107 patients (47.6 % female, mean age 58.4 years) underwent CBT for acute PE, with 23 (21.5 %) high-risk and 84 (78.5 %) intermediate-risk PE. Demographically, 64 % identified as Black, 10 % White, 19 % Hispanic or Latino, and 5 % Asian. In terms of insurance coverage, 50 % had private insurance or Medicare, 36 % had Medicaid, and 14 % were uninsured. Notably, 67 % of the patients resided in high poverty rate zip codes and 11 % were non-citizen non-residents. Over a median follow up period of 30 days, 6 (5.6 %) patients expired (all high-risk PE), 3 of whom presented with cardiac arrest. No patients who presented with intermediate-risk PE died at 30 days. There was no difference in 30-day mortality based on race, insurance type, poverty level or citizenship status. CONCLUSION/CONCLUSIONS:Our study findings reveal no disparities in access or outcomes to CBT at our SNH, emphasizing the feasibility and success of implementing PERT and CBT at a SNH, offering a potential model to address healthcare disparities in acute PE on a broader scale.