Faculty Bibliography

BACKGROUND:Heart failure-related cardiogenic shock (HF-CS) accounts for a growing proportion of cardiogenic shock (CS) related admissions to contemporary cardiac intensive care units. Limited data exists comparing non-ischemic (NICM) and ischemic cardiomyopathies (ICM) in this setting. METHODS AND RESULTS/RESULTS:We sought to examine the differences in patient characteristics, in-hospital treatments, and outcomes among individuals admitted with ICM and NICM HF-CS. The study population included CS admissions within the Critical Care Cardiology Trials Network registry from 2017 to 2022. CS due to acute myocardial infarction or secondary causes was excluded. Admission characteristics, in-hospital treatments, and outcomes were captured. The primary outcome of all-cause in-hospital mortality for ICM versus NICM was compared using multivariable logistic regression. 2,463 hospital admissions for HF-CS including 902 (36.6%) admissions with ICM and 1561 (63.4%) admissions with NICM were included. Patients with ICM more frequently had pre-existing comorbidities, pre-admission cardiac arrest, and higher Sequential Organ Failure Assessment scores. Use of inotropes and temporary mechanical circulatory support were similar; however, the rates of mechanical ventilation and renal replacement therapies were higher for ICM. Patients with ICM were less likely to undergo cardiac transplantation, but had similar rates of durable left ventricular assist device implantation. After multivariable adjustment, patients with ICM were significantly more likely to die during the index hospitalization (OR 1.56, 95% CI 1.26-1.93; p <0.001). CONCLUSIONS:Among patients admitted to CICUs with HF-CS, patients with ICM were sicker, less likely to undergo cardiac transplantation, and more likely to die when compared with patients with NICM.

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.

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/UNASSIGNED:With an increasing demand for critical care expertise and limitations in intensivist availability, innovative staffing models, such as the utilization of advanced practice providers (APPs), have emerged. OBJECTIVES/UNASSIGNED:The purpose of the study was to compare patient outcomes between APP and housestaff teams in the cardiac intensive care unit (CICU). METHODS/UNASSIGNED:This retrospective study, spanning March 2022 to July 2023, compares patient characteristics and outcomes between two CICU teams embedded in the same CICU at a large urban academic hospital: one staffed by housestaff and the other by APPs (80% physician assistants, 20% nurse practitioners) who each had approximately 1 to 2 years of experience in the CICU. The primary outcome was CICU mortality. Multivariable Cox regression analyses and Kaplan-Meier curves were used to assess the primary outcome. RESULTS/UNASSIGNED: < 0.0001). CONCLUSIONS/UNASSIGNED:Our moderately sized study demonstrated no difference in CICU or in-hospital mortality between patients managed by a housestaff team versus those managed by an APP team.

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.

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.

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.

BACKGROUND/UNASSIGNED:Sodium azide exposures are rare but can be lethal as the substance inhibits complex IV in the electron transport chain, blocking adenosine-triphosphate (ATP) synthesis. Sodium azide is mostly used as a propellant in vehicular airbags but is also used in laboratory, pharmacy, and industrial settings. No known antidote exists and its cardiotoxic effects are poorly described in the literature. CASE SUMMARY/UNASSIGNED:We describe the case of a 31-year-old patient with major depressive disorder presenting with altered mental status after ingestion of an unknown amount of sodium azide. Although initially chest pain free, she developed pleuritic chest pain 48 h after ingestion. This was accompanied by new diffuse ST elevations on the electrocardiogram and serum troponin elevations concerning for myopericarditis. Treatment was pursued with a 14-day course of colchicine resulting in complete symptom resolution within 4 days of treatment initiation. The patient's transthoracic echocardiogram was only notable for a preserved left ventricular ejection fraction (LVEF). DISCUSSION/UNASSIGNED:Cardiac toxicity after sodium azide ingestion usually occurs days after ingestion and has been previously described in the forms of heart failure with reduced ejection fraction complicated by cardiogenic shock. We describe the first case of sodium azide-induced myopericarditis with a preserved LVEF treated with colchicine. Colchicine is an established treatment for pericarditis, but its inhibition of endocytosis, an ATP-dependent cellular function, could be mechanistically relevant to this case.