Comparison of 4 Acute Pulmonary Embolism Mortality Risk Scores in Patients Evaluated by Pulmonary Embolism Response Teams

Right Ventricular-Pulmonary Arterial Uncoupling as a Predictor of Invasive Hemodynamics and Normotensive Shock in Acute Pulmonary Embolism

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.

Critical Care Management of Acute Pulmonary Embolism

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.

Optimal Cutoff Values and Utility of High-Sensitivity Troponin T and NT-proBNP for the Risk Stratification of Patients with Acute Pulmonary Embolism

BACKGROUND

Guidelines recommend using high-sensitivity troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) to risk stratify hemodynamically stable patients with acute pulmonary embolism (PE). However, there are no evidence-based cutoff values defined for this clinical application.

METHODS

We performed a single-center, retrospective cohort study of patients with imaging-confirmed PE and hsTnT and/or NT-proBNP (ElecsysTM, Roche) measured 12 h before or 24 h after PE Response Team (PERT) activation. We excluded hypotensive patients. Our primary outcome was a composite of adverse outcomes or critical interventions within 7 days. We calculated the area under the receiver operating curve (AUC, ROC) for hsTnT and NT-proBNP and determined the optimal cutoffs using the distance from (0,1). We performed a subgroup analysis on patients with PE and right ventricular dysfunction on imaging.

RESULTS

Two hundred thirty-four patients were included in the hsTnT analysis, and 727 in the NT-proBNP analysis. Mean age was 62 years (SD = 17) and 47% were female. The AUC for hsTnT was 0.64 (95% CI, 0.56-0.71) with an optimal cutoff of 46 ng/L, corresponding to a sensitivity of 59% (95% CI, 49-69) and a specificity of 61% (95% CI, 53-69). The AUC for NT-proBNP was 0.56 (95% CI, 0.51-0.61) with an optimal cutoff of 1092 pg/mL, corresponding to a sensitivity of 53% (95% CI, 45-61) and a specificity of 59% (95% CI, 55-63).

CONCLUSION

We identified an optimal cutoff of 46 ng/L for hsTnT and 1092 pg/mL for NT-proBNP, though the AUC for both markers suggests low to moderate performance for the risk stratification of initially hemodynamically stable PERT patients. Use of these biomarkers to risk stratify PE may require reconsideration.

Inferior vena cava contrast reflux grade is associated with a reduced cardiac index in acute pulmonary embolism

BACKGROUND AND AIMS

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

Substantial contrast reflux was present in 29 of 85 patients (34 %) and associated with a lower CI (1.8 ± 0.4 L/min/m2 v. 2.6 ± 1.0 L/min/m2, p < 0.001), higher pulmonary artery systolic pressure (53.2 ± 19.5 mmHg v. 44.0 ± 12.1 mmHg, p = 0.025), and worse right ventricular systolic function. An IVC contrast reflux grade > 3 was a significant predictor for a CI ≤2.2 L/min/m2 (OR: 22.5, 95 % CI: 4.8, 104.4, p < 0.001). Sensitivity, specificity, positive predictive value, and negative predictive value for substantial contrast reflux for a CI ≤2.2 L/min/m2 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.

Optimizing Use of High-Sensitivity Troponin for Risk-Stratification of Acute Pulmonary Embolism

BACKGROUND

 High-sensitivity troponin T (HS-TnT) may improve risk-stratification in hemodynamically stable acute pulmonary embolism (PE), but an optimal strategy for combining this biomarker with clinical risk-stratification tools has not been determined.

STUDY HYPOTHESIS

 We hypothesized that different HS-TnT cutoff values may be optimal for identifying (1) low-risk patients who may be eligible for outpatient management and (2) patients at increased risk of clinical deterioration who might benefit from advanced PE therapies.

METHODS

 Retrospective analysis of hemodynamically stable patients in the University of Michigan acute ED-PE registry with available HS-TnT values. Primary and secondary outcomes were 30-day mortality and need for intensive care unit-level care. Receiver operating characteristic curves were used to determine optimal HS-TnT cutoffs in the entire cohort, and for those at higher risk based on the simplified Pulmonary Embolism Severity Index (PESI) or imaging findings.

RESULTS

 The optimal HS-TnT cutoff in the full cohort, 12 pg/mL, was significantly associated with 30-day mortality (odds ratio [OR]: 3.94, 95% confidence interval [CI]: 1.48-10.50) and remained a significant predictor after adjusting for the simplified PESI (sPESI) score and serum creatinine (adjusted OR: 3.05, 95% CI: 1.11-8.38). A HS-TnT cutoff of 87 pg/mL was associated with 30-day mortality (OR: 5.01, 95% CI: 2.08-12.06) in patients with sPESI ≥1 or right ventricular dysfunction.

CONCLUSION

 In this retrospective, single-center study of acute PE patients, we identified distinct optimal HS-TnT values for different clinical uses-a lower cutoff, which identified low-risk patients even in the absence of other risk-stratification methods, and a higher cutoff, which was strongly associated with adverse outcomes in patients at increased risk.

Acute Pulmonary Embolism: Evidence, Innovation, and Horizons

PURPOSE OF REVIEW

Pulmonary embolism (PE) is the third most common cause of cardiovascular morbidity and mortality. The goal of this review is to discuss the most up-to-date literature on epidemiology, diagnosis, risk stratification, and management of acute PE.

RECENT FINDINGS

Despite an increase in annual incidence rate of PE in the United States and development of multiple advanced therapies for treatment of acute PE, PE-related mortality is not consistently decreasing across populations. Although multiple risk stratification schemes have been developed, it is still unclear which advanced therapy should be used for the individual patient and optimal timing. Fortunately, multiple randomized clinical trials are underway to answer these questions. Nevertheless, up to 50% of patients have persistent reduced quality of life 6 months after acute PE, termed post-PE syndrome. Despite advances in therapeutic options for management of acute PE, many questions remain unanswered, including optimal risk stratification and management of acute PE.

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.

Predicting Hospital Survival in Patients Admitted to ICU with Pulmonary Embolism

OBJECTIVE

The Pulmonary Embolism Severity Index (PESI) and simplified PESI (sPESI) predict mortality for patients with PE. We compared PESI/sPESI to the Acute Physiology and Chronic Health Evaluation IV (APACHE-IV) in predicting mortality in patients with PE admitted to the intensive care unit (ICU). Additionally, we assessed the performance of a novel ICU-sPESI score created by adding three clinical variables associated with acuity of PE presentation (intubation, confusion [altered mental status], use of vasoactive infusions) to sPESI.

MATERIALS AND METHODS

Using the eICU Collaborative Research Database from 2014 to 2015, we conducted a large retrospective cohort study of adult patients admitted to the ICU with a primary diagnosis of PE. We calculated APACHE-IV, PESI, sPESI, and ICU-sPESI scores and compared their performance for predicting in-hospital mortality using area under the receiver operating characteristic (AUROC) curve. Score thresholds for >99% negative predictive values (NPV) were calculated for each score. Survival was estimated using the Kaplan-Meier method.

RESULTS

We included 1424 PE cases. In-hospital mortality was 6.3% [95% CI: 5.1%-7.6%]. AUROC for APACHE-IV, PESI, and sPESI were 0.870, 0.848, and 0.777, respectively. APACHE-IV and PESI outperformed sPESI (P < 0.01 for both comparisons), while APACHE-IV and PESI demonstrated similar performance (P = 0.322). The ICU-sPESI performance was similar to APACHE-IV and PESI (AUROC = 0.847; AUROC comparison: APACHE-IV vs ICU-sPESI: P = 0.396; PESI vs ICU-sPESI: P = 0.945). Hospital mortality for ICU-sPESI scores 0-2 was 1.1%, and for scores 3, 4, 5, 6, and ≥7 was 8.6%, 11.7%, 29.2%, 37.5%, and 76.9%, respectively. Score thresholds for >99% NPV were ≤48 for APACHE-IV, ≤115 for PESI, and 0 points for sPESI and ICU-sPESI.

CONCLUSIONS

By accounting for severity of PE presentation, our newly proposed ICU-sPESI score provided improved PE mortality prediction compared to the original sPESI score and offered excellent discrimination of mortality risk.

Intermediate-Risk and High-Risk Pulmonary Embolism: Recognition and Management: Cardiology Clinics: Cardiac Emergencies

Pulmonary embolism (PE) is the third most common cause of cardiovascular death. Every specialty of medical practitioner will encounter PE in their patients, and should be prepared to employ contemporary strategies for diagnosis and initial risk-stratification. Treatment of PE is based on risk-stratification, with anticoagulation for all patients, and advanced modalities including systemic thrombolysis, catheter-directed therapies, and mechanical circulatory supports utilized in a manner paralleling PE severity and clinical context.

Ultrasound-Facilitated, Catheter-Directed Thrombolysis for Acute Pulmonary Embolism

BACKGROUND

Acute pulmonary embolism (APE) poses a significant risk to patient health, with treatment options varying in efficacy and safety. Ultrasound-facilitated catheter-directed thrombolysis (USCDT) has emerged as a potential alternative to conventional catheter-directed thrombolysis (CDT) for patients with intermediate to high-risk APE. This study aimed to compare the efficacy and safety of USCDT versus conventional CDT in patients with intermediate to high-risk APE.

METHODS

This observational retrospective study was conducted at the Armed Forces Hospital, Al-Hada, Taif, the Kingdom of Saudi Arabia (KSA), on 135 patients diagnosed with APE and treated with either USCDT or CDT (58 underwent CDT, while 77 underwent USCDT). The primary efficacy outcome was the change in the right ventricle to the left ventricle (RV/LV) diameter ratio. Secondary outcomes included changes in pulmonary artery systolic pressure and the Miller angiographic obstruction index score. Safety outcomes focused on major bleeding events.

RESULTS

Both USCDT and CDT significantly reduced RV/LV diameter ratio (from 1.35 ± 0.14 to 1.05 ± 0.17, P < 0.001) and systolic pulmonary artery pressure (SPAP) (from 55 ± 7 mmHg to 38 ± 7 mmHg, P < 0.001) at 48- and 12-hours post-procedure, respectively, with no significant differences between treatments. However, USCDT was associated with a significantly lower rate of major bleeding events compared to CDT (0% vs. 3.4%, P = 0.008). Multivariate logistic regression analysis revealed that USCDT was associated with a 71.9% risk reduction of bleeding (OR = 0.281, 95% CI = 0.126 - 0.627, P = 0.002).

CONCLUSIONS

USCDT is a safe and effective alternative to CDT for the treatment of intermediate to high-risk APE, as it significantly reduces the risk of major bleeding.

Shock score for prediction of clinical outcomes among stable patients with acute symptomatic pulmonary embolism

BACKGROUND

The Composite Pulmonary Embolism Shock (CPES) score has been developed to identify normotensive patients with acute pulmonary embolism (PE) and a low cardiac index (referred to as normotensive shock). We aimed to externally assess the validity of this model for predicting a complicated course among hemodynamically stable patients with acute PE.

METHODS

Using prospectively collected data from the PROgnosTic valuE of Computed Tomography scan (PROTECT) study, we calculated the CPES score for each patient and the proportion of patients with a score > 3. We calculated the test performance characteristics to predict a complicated course (i.e., death from any cause, hemodynamic collapse, or recurrent PE) and the discriminatory power using the area under the receiver operating characteristic curve.

RESULTS

Sixty-three of the 848 (7.4 %) patients had a complicated course during the 30-day follow-up period. Of the 848 enrolled patients, the CPES score was positive (i.e., score > 3) in 78 (9.2 %). The specificity was 92.1 % (723/785), the positive predictive value was 20.5 % (16/78), and the positive likelihood ratio was 3.22 for a complicated course. The areas under the receiver operating characteristic curve for a complicated course were 0.71 (95 % confidence interval [CI], 0.65-0.78). With the higher score risk classification threshold (cutoff score > 4), the proportion of patients designated as positive was 2.1 %, and the specificity was 98.1 %. When echocardiographic right ventricle (RV) dysfunction was replaced by computed tomographic RV enlargement, the specificity was 85.4 %, the positive predictive value was 14.2 %, and the positive likelihood ratio was 2.06 for a complicated course. When analyses were restricted to the subgroup of patients with intermediate-risk PE, the specificity and the positive predictive value for a complicated course were identical to the overall cohort.

CONCLUSIONS

The CPES score has acceptable C-statistic, excellent specificity, and low positive predictive value for identification of hemodynamic deterioration in normotensive patients with PE.

CLINICALTRIALS

gov number: NCT02238639.

Utilization of a Novel Scoring System in Predicting 30-day Mortality in Acute Pulmonary Embolism, the CLOT-5 Pilot Study

OBJECTIVES

To construct a new scoring system utilizing biomarkers, vitals, and imaging data to predict 30-day mortality in acute pulmonary embolism (PE).

BACKGROUND

Acute PE, a well-known manifestation of venous thromboembolic disease, is responsible for over 100,000 deaths worldwide yearly. Contemporary management algorithms rely on a multidisciplinary approach to care via PE response teams (PERT) in the identification of low, intermediate, and high-risk patients. The PESI and sPESI scores have been used as cornerstones of the triage process in assigning risk of 30-day mortality for patients presenting with acute PE; however, the specificity of these scoring systems has often come into question.

METHODS

This study retrospectively analyzed 488 patients with acute PE who were managed at a tertiary care institution with either conservative therapy consisting of low molecular weight or unfractionated heparin, advanced therapies consisting of catheter directed therapies, aspiration thrombectomy, or a combination of these therapies, or surgical embolectomy. The CLOT-5 score was designed to include vital signs, biomarkers, and imaging data to predict 30-day mortality in patients presenting with acute PE.

RESULTS

The CLOT-5 score had an area under the curve (AUC) of 0.901 with a standard error of 0.29, while the PESI and sPESI scores had an AUC and standard errors of 0.793 ±- 0.43 and 0.728 ± 0.55, respectively.

CONCLUSIONS

When incorporated into the management algorithms of national PERT programs, the CLOT-5 score may allow for rapid and comprehensive assessment of patients with acute PE at high risk for clinical decompensation, leading to early escalation of care where appropriate.

Risk stratification of acute pulmonary embolism

Approximately 5% of pulmonary embolism (PE) cases present with persistent hypotension, obstructive shock, or cardiac arrest. Given the high short-term mortality, management of high-risk PE cases focuses on immediate reperfusion therapies. Risk stratification of normotensive PE is important to identify patients with an elevated risk of hemodynamic collapse or an elevated risk of major bleeding. Risk stratification for short-term hemodynamic collapse includes assessment of physiological parameters, right heart dysfunction, and identification of comorbidities. Validated tools such as European Society of Cardiology guidelines and Bova score can identify normotensive patients with PE and an elevated risk of subsequent hemodynamic collapse. At present, we lack high-quality evidence to recommend one treatment over another (systemic thrombolysis, catheter-directed therapy, or anticoagulation with close monitoring) for patients at elevated risk of hemodynamic collapse. Newer, less well-validated scores such as BACS and PE-CH may help identify patients at a high risk of major bleeding following systemic thrombolysis. The PE-SARD score may identify those at risk of major anticoagulant-associated bleeding. Patients at low risk of short-term adverse outcomes can be considered for outpatient management. The simplified Pulmonary Embolism Severity Index score or Hestia criteria are safe decision aids when combined with physician global assessment of the need for hospitalization following the diagnosis of PE.

Unprovoked Venous Thromboembolism: The Search for the Cause

Venous thromboembolism (VTE) is a common vascular disorder encompassing deep vein thrombosis (DVT) and pulmonary embolism (PE). There is no data on global estimates of VTE prevalence and incidence. Most patients with unprovoked VTE require secondary thromboprophylaxis upon the completion of the primary treatment phase if they have no high bleeding risk. Risk prediction models can help identify patients at low VTE recurrence risk who may discontinue anticoagulation upon the completion of the primary treatment phase.

Prediction of in-hospital deterioration in normotensive pulmonary embolism remains elusive: external validation of the calgary acute pulmonary embolism score

Acute pulmonary embolism (PE) is a frequently diagnosed condition. Prediction of in-hospital deterioration is challenging with current risk models. The Calgary Acute Pulmonary Embolism (CAPE) score was recently derived to predict in-hospital adverse PE outcomes but has not yet been externally validated. Retrospective cohort study of normotensive acute pulmonary embolism cases diagnosed in our emergency department between 2017 and 2019. An external validation of the CAPE score was performed in this population for prediction of in-hospital adverse outcomes and a secondary outcome of 30-day all-cause mortality. Performance of the simplified Pulmonary Embolism Severity Index (sPESI) and Bova score was also evaluated. 712 patients met inclusion and exclusion criteria, with 536 patients having a sPESI score of 1 or more. Among this population, the CAPE score had a weak discriminative power to predict in-hospital adverse outcomes, with a calculated c-statistic of 0.57. In this study population, an external validation study found weak discriminative power of the CAPE score to predict in-hospital adverse outcomes among normotensive PE patients. Further efforts are needed to define risk assessment models that can identify normotensive PE patients at risk for in hospital deterioration. Identification of such patients will better guide intensive care utilization and invasive procedural management of PE.

Developing Validated Tools to Identify Pulmonary Embolism in Electronic Databases: Rationale and Design of the PE-EHR+ Study

BACKGROUND

 Contemporary pulmonary embolism (PE) research, in many cases, relies on data from electronic health records (EHRs) and administrative databases that use International Classification of Diseases (ICD) codes. Natural language processing (NLP) tools can be used for automated chart review and patient identification. However, there remains uncertainty with the validity of ICD-10 codes or NLP algorithms for patient identification.

METHODS

 The PE-EHR+ study has been designed to validate ICD-10 codes as Principal Discharge Diagnosis, or Secondary Discharge Diagnoses, as well as NLP tools set out in prior studies to identify patients with PE within EHRs. Manual chart review by two independent abstractors by predefined criteria will be the reference standard. Sensitivity, specificity, and positive and negative predictive values will be determined. We will assess the discriminatory function of code subgroups for intermediate- and high-risk PE. In addition, accuracy of NLP algorithms to identify PE from radiology reports will be assessed.

RESULTS

 A total of 1,734 patients from the Mass General Brigham health system have been identified. These include 578 with ICD-10 Principal Discharge Diagnosis codes for PE, 578 with codes in the secondary position, and 578 without PE codes during the index hospitalization. Patients within each group were selected randomly from the entire pool of patients at the Mass General Brigham health system. A smaller subset of patients will also be identified from the Yale-New Haven Health System. Data validation and analyses will be forthcoming.

CONCLUSIONS

 The PE-EHR+ study will help validate efficient tools for identification of patients with PE in EHRs, improving the reliability of efficient observational studies or randomized trials of patients with PE using electronic databases.

Fibrinolytic Status and Risk of Death After Acute Pulmonary Embolism

BACKGROUND

Acute pulmonary embolism (PE) is a heterogeneous disease process with variable presentation and outcomes. The endogenous fibrinolytic system is a complex framework of regulatory pathways that maintains homeostasis by dissolving overabundant thrombi. We sought to investigate phenotypic profiles of the endogenous fibrinolytic system among patients presenting with acute PE and their impact on mortality.

METHODS

We enrolled all consecutive patients with acute PE in our institutional Pulmonary Embolism Response Team registry. We collected blood samples at the time of PE diagnosis and analyzed concentrations of plasminogen activator inhibitor 1 (PAI-1), thrombin-activatable fibrinolysis inhibitor (TAFI), and alpha-2-antiplasmin (A2A). We assessed the association of concentration of fibrinolytic inhibitors and 1-year all-cause mortality and various echocardiographic markers of right ventricular (RV) dysfunction.

RESULTS

There is significant variability of PAI-1, A2A, and TAFI concentrations across the spectrum of PE risk profiles with high PAI-1, low TAFI, and low A2A (herein referred to as a high-risk biomarker profile) correlating with worse PE severity. High-risk biomarker profile correlated with high-risk echocardiographic features of RV dysfunction, including increased RV/left ventricular (LV) ratio, low tricuspid annular plane systolic excursion, and low right ventricular outflow tract velocity time integral. Higher-risk biomarker profile was able to discriminate and independently identify patients at high risk of all-cause mortality (Group 2 HR 6 95% CI 1.3-27.8, Group 3 HR 12, 95% CI 1.7-86).

CONCLUSIONS

Further studies are needed to assess the exact pathophysiological link between fibrinolytic status and poor outcome after acute PE and to ascertain the impact of anti-inhibitors of the fibrinolytic system on response to therapy and outcomes after acute PE.

Catheter-directed therapies for the treatment of high risk (massive) and intermediate risk (submassive) acute pulmonary embolism

BACKGROUND

Acute pulmonary embolism (APE) is a major cause of acute morbidity and mortality. APE results in long-term morbidity in up to 50% of survivors, known as post-pulmonary embolism (post-PE) syndrome.  APE can be classified according to the short-term (30-day) risk of mortality, based on a variety of clinical, imaging and laboratory findings. Most mortality and morbidity is concentrated in high-risk (massive) and intermediate-risk (submassive) APE. The first-line treatment for APE is systemic anticoagulation.  High-risk (massive) APE accounts for less than 10% of APE cases and is a life-threatening medical emergency, requiring immediate reperfusion treatment to prevent death. Systemic thrombolysis is the recommended treatment for high-risk (massive) APE. However, only a minority of the people affected receive systemic thrombolysis, due to comorbidities or the 10% risk of major haemorrhagic side effects. Of those who do receive systemic thrombolysis, 8% do not respond in a timely manner. Surgical pulmonary embolectomy is an alternative reperfusion treatment, but is not widely available.  Intermediate-risk (submassive) APE represents 45% to 65% of APE cases, with a short-term mortality rate of around 3%. Systemic thrombolysis is not recommended for this group, as major haemorrhagic complications outweigh the benefit. However, the people at higher risk within this group have a short-term mortality of around 12%, suggesting that anticoagulation alone is not an adequate treatment. Identification and more aggressive treatment of people at intermediate to high risk, who have a more favourable risk profile for reperfusion treatments, could reduce short-term mortality and potentially reduce post-PE syndrome. Catheter-directed treatments (catheter-directed thrombolysis and catheter embolectomy) are minimally invasive reperfusion treatments for high- and intermediate-risk APE. Catheter-directed treatments can be used either as the primary treatment or as salvage treatment after failure of systemic thrombolysis. Catheter-directed thrombolysis administers 10% to 20% of the systemic thrombolysis dose directly into the thrombus in the lungs, potentially reducing the risks of haemorrhagic side effects. Catheter embolectomy mechanically removes the thrombus without the need for thrombolysis, and may be useful for people with contraindications for thrombolysis.  Currently, the benefits of catheter-based APE treatments compared with existing medical and surgical treatment are unclear despite increasing adoption of catheter treatments by PE response teams. This review examines the evidence for the use of catheter-directed treatments in high- and intermediate-risk APE. This evidence could help guide the optimal treatment strategy for people affected by this common and life-threatening condition.

OBJECTIVES

To assess the effects of catheter-directed therapies versus alternative treatments for high-risk (massive) and intermediate-risk (submassive) APE.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search was 15 March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of catheter-directed therapies for the treatment of high-risk (massive) and intermediate-risk (submassive) APE. We excluded catheter-directed treatments for non-PE. We applied no restrictions on participant age or on the date, language or publication status of RCTs.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. The main outcomes were all-cause mortality, treatment-associated major and minor haemorrhage rates based on two established clinical definitions, recurrent APE requiring retreatment or change to a different APE treatment, length of hospital stay, and quality of life. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We identified one RCT (59 participants) of (ultrasound-augmented) catheter-directed thrombolysis for intermediate-risk (submassive) APE. We found no trials of any catheter-directed treatments (thrombectomy or thrombolysis) in people with high-risk (massive) APE or of catheter-based embolectomy in people with intermediate-risk (submassive) APE. The included trial compared ultrasound-augmented catheter-directed thrombolysis with alteplase and systemic heparinisation versus systemic heparinisation alone. In the treatment group, each participant received an infusion of alteplase 10 mg or 20 mg over 15 hours. We identified a high risk of selection and performance bias, low risk of detection and reporting bias, and unclear risk of attrition and other bias. Certainty of evidence was very low because of risk of bias and imprecision.  By 90 days, there was no clear difference in all-cause mortality between the treatment group and control group. A single death occurred in the control group at 20 days after randomisation, but it was unrelated to the treatment or to APE (odds ratio (OR) 0.31, 95% confidence interval (CI) 0.01 to 7.96; 59 participants). By 90 days, there were no episodes of treatment-associated major haemorrhage in either the treatment or control group. There was no clear difference in treatment-associated minor haemorrhage between the treatment and control group by 90 days (OR 3.11, 95% CI 0.30 to 31.79; 59 participants). By 90 days, there were no episodes of recurrent APE requiring retreatment or change to a different APE treatment in the treatment or control group. There was no clear difference in the length of mean total hospital stay between the treatment and control groups. Mean stay was 8.9 (standard deviation (SD) 3.4) days in the treatment group versus 8.6 (SD 3.9) days in the control group (mean difference 0.30, 95% CI -1.57 to 2.17; 59 participants). The included trial did not investigate quality of life measures.  AUTHORS' CONCLUSIONS: There is a lack of evidence to support widespread adoption of catheter-based interventional therapies for APE. We identified one small trial showing no clear differences between ultrasound-augmented catheter-directed thrombolysis with alteplase plus systemic heparinisation versus systemic heparinisation alone in all-cause mortality, major and minor haemorrhage rates, recurrent APE and length of hospital stay. Quality of life was not assessed.  Multiple small retrospective case series, prospective patient registries and single-arm studies suggest potential benefits of catheter-based treatments, but they provide insufficient evidence to recommend this approach over other evidence-based treatments. Researchers should consider clinically relevant primary outcomes (e.g. mortality and exercise tolerance), rather than surrogate markers (e.g. right ventricular to left ventricular (RV:LV) ratio or thrombus burden), which have limited clinical utility. Trials must include a control group to determine if the effects are specific to the treatment.

Intermediate-risk pulmonary embolism: echocardiography predictors of clinical deterioration

Background

We determine the predictive value of transthoracic echocardiographic (TTE) metrics for clinical deterioration within 5 days in adults with intermediate-risk pulmonary embolism (PE).

Methods

This was a prospective observational study of intermediate-risk PE patients. To determine associations of TTE and clinical predictors with clinical deterioration, we used univariable analysis, Youden’s index for optimal thresholds, and multivariable analyses to report odds ratios (ORs) or area under the curve (AUC).

Results

Of 306 intermediate-risk PE patients, 115 (37.6%) experienced clinical deterioration. PE patients who had clinical deterioration within 5 days had greater baseline right ventricle (RV) dilatation and worse systolic function than the group without clinical deterioration as indicated by the following: RV basal diameter 4.46 ± 0.77 versus 4.20 ± 0.77 cm; RV/LV basal width ratio 1.14 ± 0.29 versus 1.02 ± 0.24; tricuspid annular plane systolic excursion (TAPSE) 1.56 ± 0.55 versus 1.80 ± 0.52 cm; and RV systolic excursion velocity 10.40 ± 3.58 versus 12.1 ± 12.5 cm/s, respectively. Optimal thresholds for predicting clinical deterioration were: RV basal width 3.9 cm (OR 2.85 [1.64, 4.97]), RV-to-left ventricle (RV/LV) ratio 1.08 (OR 3.32 [2.07, 5.33]), TAPSE 1.98 cm (OR 3.3 [2.06, 5.3]), systolic excursion velocity 10.10 cm/s (OR 2.85 [1.75, 4.63]), and natriuretic peptide 190 pg/mL (OR 2.89 [1.81, 4.62]). Significant independent predictors were: transient hypotension 6.1 (2.2, 18.9), highest heart rate 1.02 (1.00, 1.03), highest respiratory rate 1.02 (1.00, 1.04), and RV/LV ratio 1.29 (1.14, 1.47). By logistic regression and random forest analyses, AUCs were 0.80 (0.73, 0.87) and 0.78 (0.70, 0.85), respectively.

Conclusions

Basal RV, RV/LV ratio, and RV systolic function measurements were significantly different between intermediate-risk PE patients grouped by subsequent clinical deterioration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04030-z.

Comparison of 5 acute pulmonary embolism mortality risk scores in patients with COVID-19

Objective

Methods

Results

Conclusion

Current interventional therapies in acute pulmonary embolism

Pulmonary embolism (PE) is the third leading cause of cardiovascular mortality. The management of PE is currently evolving given the development of new technologies and team-based approaches. This document will focus on risk stratification of PEs, review of the current interventional therapies, the role of clinical endpoints to assess the effectiveness of different interventional therapies, and the role for mechanical circulatory support in the complex management of this disease.

Mortality in Pulmonary Embolism According to Risk Category at Presentation in Emergency Department: Impact of Cardiac Arrest

In this investigation we explore whether assessment of the risk of mortality can be refined by stratifying high-risk patients with pulmonary embolism (PE) according to whether they had cardiac arrest. We stratified high-risk patients according to whether they had shock but no cardiac arrest, or cardiac arrest diagnosed in the emergency department (ED). This was a retrospective cohort study based on administrative data from the Nationwide Emergency Department Sample (NEDS), 2016. Included patients were 274,227 who were admitted to the same hospital as the ED or died in the ED. This was 77% of 354,616 patients with pulmonary embolism seen in the ED in 2016. Patients were identified based on International Classification of Diseases, 10th Edition, Clinical Modification (ICD-10-CM) Codes. High-risk with no cardiac arrest were 4,317 of 274,227 (1.6%) and high-risk with cardiac arrest were 1,027 of 274,227 (0.4%). Mortality of high-risk patients who did not have cardiac arrest was 1,753 of 4,317 (41%). Mortality of high-risk patients who had cardiac arrest was 754 of 1027 (74%). Mortality increased with age in high-risk patients who did not have cardiac arrest, but mortality was not age-related in high-risk patients with cardiac arrest. In conclusion, high-risk patients with PE are a heterogeneous group and stratification according to whether they had cardiac arrest refines risk assessment.

The safety and efficacy of systemic versus catheter-based therapies: application of a prognostic model by a pulmonary embolism response team

The decision by pulmonary embolism response teams (PERTs) to utilize anticoagulation (AC) with or without systemic thrombolysis (ST) or catheter-directed therapies (CDT) for pulmonary embolism (PE) is a balance between the desire for a positive outcome and safety. Our primary aim was to develop a predictive model of in-hospital mortality for patients with high- or intermediate-risk PE managed by PERT while externally validating this model. Our secondary aim was to compare the relative safety and efficacy of ST and CDT in this cohort. Consecutive patients hospitalized between June 2014 and January 2020 at the Cleveland Clinic Foundation and The University of Rochester with acute high- or intermediate-risk PE managed by PERT were retrospectively evaluated. Groups were stratified by treatment strategy. The primary outcome was in-hospital mortality, and secondary outcome was major bleeding. A logistic regression model to predict the primary outcome was built using the derivation cohort, with 100-fold bootstrapping for internal validation. External validation was performed and the area under the receiver operating curve (AUC) was calculated. Of 549 included patients, 421 received AC alone, 71 received ST, and 64 received CDT. Predictors of major bleeding include ESC risk category, PESI score, hypoxia, hemodynamic instability, and serum lactate. CDT trended towards lower mortality but with an increased risk of bleeding relative to ST (OR = 0.42; 95% CI [0.15, 1.17] and OR = 2.14; 95% CI [0.9, 5.06] respectively). In the multivariable logistic regression model in the derivation institution cohort, predictors of in-hospital mortality were age, cancer, hemodynamic instability requiring vasopressors, and elevated NT-proBNP (AUC = 0.86). This model was validated using the validation institution cohort (AUC = 0.88). We report an externally-validated model for predicting in-hospital mortality in patients with PE managed by PERT. The decision by PERT to initiate CDT or ST for these patients had no impact on mortality or major bleeding, yet the long-term efficacy of these interventions needs to be elucidated.

Resting heart rate as a surrogate for improvement in intermediate risk pulmonary embolus patients?

BACKGROUND

Pulmonary embolism (PE) response teams (PERT) have been developed to improve in-hospital mortality. Identifying intermediate risk PE patients that will progress despite anticoagulation is difficult, especially because outcomes with modern anticoagulation are quite good.

OBJECTIVE

The primary aim of this study was to evaluate the rate of anticoagulation failure (new deep vein thrombosis or PE, right ventricular failure resulting in shock, cardiac arrest, or PE-attributable death) in intermediate risk PE patients managed by PERT. The secondary objective was to determine whether there was a significant decrease in heart rate 24 h after initiation of anticoagulation in intermediate risk PE.

METHODS

This was a retrospective observational study of patients treated for acute intermediate risk PE at the University of Rochester Medical Center who also had outpatient followup between November 2016-June 2019.

RESULTS

Ninety-two patients presented as intermediate-risk PE and had outpatient followup. Seventy-four patients were initially treated with anticoagulation. None of these patients failed anticoagulation. Of the eighteen intermediate risk patients that underwent advanced intervention, none failed anticoagulation first. There was significant decrease in resting heart rate 24 h after starting therapeutic anticoagulation, 107 beats/min vs 89 beats/min, p = 0.0001.

CONCLUSION

We did not observe anticoagulation failure in the management of acute, intermediate risk PE. Reductions in heart rate may reflect improvements in right ventricular function; we hypothesize that those whose heart rate does not fall may be optimal candidates for advanced intervention.

Rapid prediction of deterioration risk among non-high-risk patients with acute pulmonary embolism at admission: An imaging tool

BACKGROUND

Computed tomography (CT) pulmonary angiography as the first-line diagnosis tool of acute pulmonary embolism (PE), might improve this discriminatory power. We aimed to developed a simply tool combining multi-CT parameters to complete individualized risk assessment of deterioration in non-high-risk patients with acute PE at admission.

METHOD

Consecutive non-high-risk patients with acute PE who were treated in a Chinese center during 2010-2021, were collected.Prognosis-related CT parameters were reviewed. Deterioration was defined as any adverse event within 30 day after admission. Eligible patients were randomized into derivation and validation cohorts. In the derivation cohort, CT parameters were screened for importance using classification tree methodology and enrolled variables was partitioned via curve-fitting and dose-response analysis. A nomogram was developed and the predictive power in both cohorts was evaluated based on the area under the receiver operating characteristic curve (AUROC) and the corresponding 95% confidence interval (CI).

RESULT

A total of 1001 patients were included. The preliminary analyses revealed that deterioration risk was related to the right-to-left ventricular diameter ratio at 4-chamber view, pulmonary vein filling abnormality. After a curve-fitting to deterioration risk, these parameters were partitioned and used to develop a nomogram, which had AUROC values of 0.91 (95% CI: 0.87-0.96) in the derivation cohort and 0.89 (95% CI: 0.81-0.97) in the validation cohort. A web-based version of the radiomics scoring tool was published online for use in clinical practice (https://acutepeprediction.shinyapps.io/Radiomics_Predictive_Tool/).

CONCLUSION

This simply tool can complete rapid estimation of deterioration risk among non-high-risk acute PE patients at admission.

Angiopoietin-2 correlates with pulmonary embolism severity, right ventricular dysfunction, and intensive care unit admission

Risk stratification of acute pulmonary embolism (PE) is important to identify patients at risk for hemodynamic collapse who would benefit from more aggressive therapies. Angiopoietin-2 (Ang-2) is a signaling molecule involved in angiogenesis and is upregulated in response to tissue hypoxia. We aimed to assess the association of Ang-2 with (1) PE severity, (2) echocardiographic and invasive hemodynamic markers of right ventricular (RV) dysfunction, and (3) need for intensive treatment. Patients presenting to our institution with acute PE were included in a prospective database and blood samples were collected and stored for later analysis. A total of 65 patients were included in the study. Ang-2 correlated with PE risk stratification and echocardiographic and invasive hemodynamic markers of RV dysfunction and pulmonary hypertension. An Ang-2 level of > 4101 pg/mL had an odds ratio of 7.4 (95% CI: 1.53-12.5, p < 0.01) for intensive care unit (ICU) admission. In conclusion, Ang-2 correlates with PE severity, RV dysfunction, and need for ICU admission. Ang-2 holds promise as a novel marker that can aid in risk stratification for this patient population.