Faculty Bibliography

BACKGROUND:Patients with intermediate-risk pulmonary embolism (PE) have outcomes worse than uncomplicated ST elevation myocardial infarction. Yet, no large-scale study has compared the outcomes of large-bore mechanical thrombectomy (LBMT) with anticoagulation alone (AC). The aim of this study was to compare the clinical outcomes among patients receiving LBMT vs AC alone. METHODS:This was a two-center retrospective study that included patients with intermediate-risk PE from October 2016 - October 2023 from the institution's Pulmonary Embolism Response Team (PERT) database. The primary outcome was a composite of 30-day mortality, resuscitated cardiac arrest or hemodynamic decompensation. Inverse probability of treatment weighting (IPTW) was used to balance covariates; Kaplan Meir curves and IPTW multivariable Cox regression were used to assess the relationship between treatment groups and outcomes. RESULTS:Of the 273 patients included in the analysis, 192 (70 %) patients received AC alone and 81 (30 %) patients received LBMT and AC. A total of 30 (10.9 %) patients experienced the primary composite outcome over a median follow-up of 30 days. The primary composite outcome was significantly lower in the group that received LBMT compared to those on AC alone (1.2 % vs 15.1 %, log-rank p < 0.001; adjusted HR: 0.02; 95 % CI: 0.002-0.17, p < 0.001) driven by a lower rate of 30-day all-cause mortality (0 % vs 7.3 %, log-rank p = 0.01), resuscitated cardiac arrest (0 % vs 6.8 %, log-rank p = 0.016) and new or worsening hemodynamic instability (4 % vs 11.1 %, log-rank p = 0.007). CONCLUSION/CONCLUSIONS:In this largest cohort to date comparing LBMT versus AC alone in acute intermediate-risk PE, LBMT had a significantly lower rate of the primary composite outcome including a lower rate of all-cause mortality when compared to AC alone. Ongoing randomized trials will test these associations.

Intravenous (IV) digoxin loading dose recommendations for rate control of atrial arrhythmias in critically ill patients are not well studied. When using digoxin in the setting of atrial fibrillation/atrial flutter (AF/AFL), a loading dose (LD) in either a fixed-dose regimen, weight-based dose, or pharmacokinetic-based calculation to target a serum digoxin concentration (SDC) of 0.8-1.5 ng/mL is recommended. The objective of this study was to assess the safety and effectiveness of digoxin LD used in critically ill patients for rate control of AF/AFL and to assess the SDC achieved. This single center retrospective cohort study included patients who received IV digoxin and had a SDC drawn. The primary endpoint was the median SDC achieved after a digoxin LD. Secondary outcomes included the frequency of SDCs ≥1.5 ng/mL and heart rate (HR) control. A total of 92 patients were included. The median total LD of digoxin for the entire cohort was 11mcg/kg (750 mcg). For 61% of the cohort, the LD was distributed over six-hour intervals. The median SDC after completion of the IV digoxin LD was 1.3 ng/mL (0.9, 1.7). The incidence of supratherapeutic SDC was 36% for the total cohort. A target HR < 110 beats per minute within 24 hours from digoxin LD was achieved in 60% of the cohort. In conclusion, a median total digoxin LD of 750 mcg in critically ill patients with AF/AFL, targeting a SDC < 1.5ng/mL may be considered for acute rate control, taking into account drug-drug interactions in the cardiac intensive care unit. Future studies are necessary to confirm our findings.

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.

The unprimed right ventricle is exquisitely sensitive to acute elevations in afterload. High pulmonary vascular tone incurred with acute pulmonary embolism has the potential to induce obstructive shock and circulatory collapse. While emergent pulmonary reperfusion is essential in severe circumstances, an important subset of pulmonary embolism patients may exhibit a less extreme presentation posing a management dilemma. As intensive care therapies have the potential to both salvage and harm the failing right ventricle, a keen understanding of the pathophysiology is requisite in the care of the contemporary patient with hemodynamically significant pulmonary embolism. Here, we review right ventricular pathophysiology, an approach to risk stratification, and offer guidance on the medical and mechanical supportive and therapeutic strategies for the critically ill patient with acute pulmonary embolism.

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.

The provision of positive pressure ventilation has the potential to provoke hemodynamic deterioration. The subject of heart-lung interactions is both complex and critical yet often obscure and fraught with misconception among trainees and seasoned clinicians alike. In this article, we focus on the impact of positive pressure ventilation on the right heart, providing a teaching approach composed of didactic sessions and simulated cases. We split our didactics and cases into two 30-minute sessions: "How the right heart fills" and "How the right heart empties." Within each session, our framework highlights key concepts with respect to circulatory physiology, respiratory system mechanics, and an amalgam of the two subjects as it pertains to managing clinical scenarios encountered during a trainee's intensive care unit rotation.

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:and clinical evidence of hypoperfusion (i.e. elevated lactate, oliguria). The primary outcome was the association between McConnell's sign and normotensive shock. RESULTS:, 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/CONCLUSIONS: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.