Hestia criteria can safely select patients with pulmonary embolism for outpatient treatment irrespective of right ventricular function

Clinical Presentation and Risk Stratification of Pulmonary Embolism

Pulmonary embolism (PE) presents with a spectrum of symptoms, ranging from asymptomatic cases to life-threatening events. Common symptoms include sudden dyspnea, chest pain, limb swelling, syncope, and hemoptysis. Clinical presentation varies based on thrombus burden, demographics, and time to presentation. Diagnostic evaluation involves assessing symptoms, physical examination findings, and utilizing laboratory tests, including D-dimer. Risk stratification using tools like Wells score, Pulmonary Embolism Severity Index, and Hestia criteria aids in determining the severity of PE. PE is categorized based on hemodynamic status, temporal patterns, and anatomic locations of emboli to guide in making treatment decisions. Risk stratification plays a crucial role in directing management strategies, with elderly and comorbid individuals at higher risk. Early identification and appropriate risk stratification are essential for effective management of PE. As we delve into this review article, we aim to enhance the knowledge base surrounding PE, contributing to improved patient outcomes through informed decision-making in clinical practice.

Identification of Low-risk Patients With Acute Symptomatic Pulmonary Embolism

BACKGROUND

Identification of patients with acute symptomatic pulmonary embolism (PE) who are at low-risk for short-term complications to warrant outpatient care lacks clarity.

METHOD

In order to identify patients at low-risk for 30-day all-cause and PE-related mortality, we used a cohort of haemodynamically stable patients from the RIETE registry to compare the false-negative rate of four strategies: the simplified Pulmonary Embolism Severity Index (sPESI); a modified (i.e., heart rate cutoff of 100beats/min) sPESI; and a combination of the original and the modified sPESI with computed tomography (CT)-assessed right ventricle (RV)/left ventricle (LV) ratio.

RESULTS

Overall, 137 of 3117 patients with acute PE (4.4%) died during the first month. Of these, 41 (1.3%) died from PE, and 96 (3.1%) died from other causes. The proportion of patients categorized as having low-risk was highest with the sPESI and lowest with the combination of a modified sPESI and CT-assessed RV/LV ratio (32.5% versus 16.5%; P<0.001). However, among patients identified as low-risk, the 30-day mortality rate was lowest with the combination of a modified sPESI and CT-assessed RV/LV ratio and highest with the sPESI (0.4% versus 1.0%; P=0.03). The 30-day PE-related mortality rates for patients designated as low-risk by the sPESI, the modified sPESI, and the combination of the original and modified sPESI with CT-assessed RV/LV ratio were 0.7%, 0.4%, 0.7%, and 0.2%, respectively.

CONCLUSIONS

The combination of a negative modified sPESI with CT-assessed RV/LV ratio ≤1 identifies patients with acute PE who are at very low-risk for short-term mortality.

Validation of clinical-radiological scores for prognosis of mortality in acute pulmonary embolism

INTRODUCTION

Acute pulmonary embolism (APE) is a hazardous disorder with a high mortality. Combination of clinical, radiological, and serological parameters can improve risk stratification of APE. Most of the proposed combined scores were not validated in independent cohorts. Our aim was to validate the proposed clinical-radiological scores for prognosis of 7- and 30-day mortality in APE.

MATERIALS AND METHODS

Our sample comprised 531 patients with APE, mean age 64.8 ± 15.6 years, 221 (41.6%) females and 310 (58.4%) males. The following parameters were collected: Age and sex of the patients, mortality within the observation time of 30 days, simplified pulmonary embolism severity index (sPESI), pH troponin level (pg/ml), minimal systolic and diastolic blood pressures (mmHg), heart rate, O2 saturation, episodes of syncope, and need for vasopressors. On CT pulmonary angiography (CTPA), short axis ratio right ventricle/left ventricle (RV/LV), and reflux of contrast medium into the inferior vena cava were obtained. The following clinical-radiological scores were calculated: BOVA score, pulmonary embolism mortality score (PEMS), European Society of Cardiology (ESC) score, Kumamaru score, and Calgary acute pulmonary embolism (CAPE) score.

RESULTS

Overall, 31 patients (5.8%) died within seven and 64 patients (12%) within 30 days. All scores showed high negative prognostic values ranging from 89.0 to 99.0%. PEMS and CAPE score demonstrated the highest specificity for 7-day mortality (93.4% and 85.0%), PEMS and BOVA for 30-day mortality (94.2% and 90.4%). The highest sensitivity was observed for ESC 2019 (96.8% and 95.3%). Kumamaru and CAPE scores had low sensitivity. All scores had low positive and high negative predictive values.

CONCLUSION

For prognosis of 7- and 30-day mortality in APE, PEMS score has the highest specificity. ESC 2019 shows the highest sensitivity. All scores had low positive and high negative predictive values.

Usefulness of the National Early Warning Score for Risk Stratification of Stable Patients With Acute Symptomatic Pulmonary Embolism

OBJECTIVES

The aim of this study was to assess the performance of the National Early Warning Score 2 (NEWS2) in predicting a short-term complicated outcome in stable patients with acute symptomatic pulmonary embolism (PE). We also studied the ability of the NEWS2 score compared with the simplified Pulmonary Embolism Severity Index (sPESI) for identifying low-risk patients with acute PE.

METHODS

We performed a retrospective analysis of a prospective cohort composed of 848 patients with acute PE. The NEWS2 and the sPESI were calculated for each patient according to different clinical variables. We assessed the predictive accuracy of these scores for a 30-day complicated outcome using the C statistic, which was obtained by logistic regression models and ROC curves. We also assessed the test and performance characteristics of the low-risk versus high-risk categories of each prediction rule.

RESULTS

Overall, 63 out of 848 patients died (7.4%; 95% confidence interval, 5.7%-9.2%) during the first month of follow-up. Both scores showed a similarly poor predictive value for 30-day complicated outcome (C statistic, 0.68 and 0.62). The sPESI classified fewer patients as low-risk (36.9% versus 44.5%; P<0.01). Compared with the NEWS2 score, the sPESI showed significantly higher sensitivity (92.1% versus 66.7%) and a better negative predictive value (98.4% versus 94.4%).

CONCLUSION

Both scores provide similar information for stratifying the risk of a complicated outcome in stable patients with PE. The sPESI identified low-risk patients with PE better than the NEWS2 score.

[Home treatment of low-risk pulmonary embolism patients : Efficacy and safety of an outpatient program including the general practitioner]

AIM

Outpatient treatment (OT) of patients with low-risk pulmonary embolisms (PE) is recommended. A multidisciplinary OT program including the general practitioner (GP) has been implemented at Versailles hospital in 2019. The objectives of the study were to assess the feasibility, safety and acceptability of the program.

MATERIAL AND METHODS

The feasibility of, and the inclusion criteria for OT were defined from a retrospective cohort study of PE patients carried out in 2018. In the prospective study, consecutive patients consulting in the emergency department between 2019 and 2021 with confirmed PE were eligible for OT if they had sPESI and HESTIA scores equal to 0, normal troponin and NT-pro-BNP levels, and no right ventricular dilation on imaging. PEs associated with COVID were excluded. The OT program included 4 appointments within 3 months, including 2 with the GP. Events (death, recurrence of PE or venous thromboembolism, bleeding, rehospitalisation) were collected at 3-month follow-up.

RESULTS

In the retrospective study, 19% of the 138 PE patients seen in the emergency department were eligible for OT. No complication occurred at Day 90. In the prospective study, 313 consecutive patients with confirmed PE in the emergency department were included, 66 (21%) were eligible for OT. Overall, 43 patients (14%) received OT (39 eligible) and 27 patients eligible for OT were hospitalised (92% because of pulmonary infarction). At 3-month follow-up, there were no death, no recurrence of thromboembolism, and one patient has been early hospitalised for COVID; 3 female patients treated with rivaroxaban had minor bleeding (heavy menstrual bleeding). The satisfaction rate of general practitioner was 95%.

CONCLUSIONS

This study confirms the feasibility and safety of our OT program for low-risk EP patients, centered on the general practitioner. It reduces the time spent in the emergency department, reduces hospitalisations and strengthens the city-hospital link for care.

Classification and Stratification of Pulmonary Embolisms

Pulmonary embolism remains a leading cause of cardiovascular mortality. Presentation and outcomes are variable among patients and require rapid risk stratification for assessment and prognosis, as well as selection of appropriate treatment. Over the past several decades, several different models and parameters have become available to assess risk and classify pulmonary embolism into different risk categories. Some patients may be candidates for early discharge or complete outpatient treatment, while some may require invasive diagnostics and intensive monitoring. In this review, we summarize contemporary guidelines and methods for classification and risk stratification in an effort to provide tools for physicians to use in their management of patients with acute pulmonary embolisms.

Pharmacoeconomic, Medication Access, and Patient-Satisfaction Analysis of a Pharmacist-Managed VTE Clinic Compared to Primary Care Physician Outpatient Therapy

Venous thromboembolism (VTE) is a common medical condition often treated with direct oral anticoagulants (DOACs). Current literature supports outpatient treatment of select, low-risk VTE patients by a pharmacist with DOACs; however, no studies exist to demonstrate if a pharmacist-managed VTE clinic provides financial benefit compared to physician-managed outpatient care. To compare the financial implications and patient satisfaction of pharmacist-managed VTE care versus outpatient VTE care by a primary care physician. A single-center retrospective chart review was conducted on all patients seen at a pharmacist-managed VTE clinic for safety and reimbursement outcomes between August 1, 2018 and July 31, 2019. These data points were used to assess the primary endpoint of net gain per patient visit and secondary outcomes, including patient satisfaction score. The primary outcome median (IQR) for net gain per visit was $16.57 (16.57, 16.57) for the pharmacist-managed group and $64.37 (47.04, 64.37) in the physician-managed group with a 95% CI of 39.13-47.80. The median cost to the organization per visit was $4.96 (4.96, 4.96) for the pharmacist-managed group and $39.41 (23.65, 39.41) for the physician managed group with a 95% CI of 26.57-34.45. Statistical difference was also found for a secondary outcome of percentage of days covered for the pharmacist-managed group compared to the physician managed group, median (IQR) 100% (76,100) vs 92.2% (67.2, 98.9) respectfully, with a p-value of 0.043. The pharmacist-managed VTE clinic, although financially sustainable, provides significantly less net revenue per patient than physician managed clinics, demonstrating the need for increased payer recognition for pharmacists.

Evaluating the Appropriateness of Pulmonary Embolism Admissions in a Community Hospital Emergency Department

Pulmonary embolism (PE) is a diagnosis on the broader spectrum of venous thromboembolic (VTE) disease. The diagnostic key for clinicians is detecting which patients have a "high risk" of complications or mortality and who are in the "low-risk" population. The Pulmonary Embolism Severity Index (PESI) and HESTIA scores are validated risk stratification tools to determine if patients diagnosed with PE can be successfully managed in the outpatient versus inpatient setting. We aimed to investigate the appropriateness of PE admissions to our institution based on the risk stratification recommendations from PESI and HESTIA scores. We retrospectively identified 175 patients admitted with a diagnosis of PE over one year at our hospital. Baseline demographics, length of admission, and admitting diagnoses were collected for all patients included in this study. PESI and HESTIA scores were then calculated for all included patients. The average PESI score was 91.65 (95% confidence interval: 86.33, 96.97). There were 87 patients (49.7%) that had a low or very low PESI score of fewer than 85 points. Fifty-seven patients (33.7%) presented with a HESTIA score of 0. The risk stratification score indicates these patients as low risk, and appropriate for outpatient management. However, they were instead admitted to the hospital which contributes to increased costs, risk of adverse events, etc. There were 0 mortalities reported for patients in the "low or very low risk" groups, with four reported mortalities in the "very high risk" groups.  In our cohort, 33.7%-49.7% of admissions for PE were risk-stratified as "low risk" and qualified for outpatient management based on HESTIA and PESI risk stratification scores, respectively. The underutilization of validated risk scores upon initial diagnosis of PE may lead to worse outcomes and increased healthcare expenditure.

A Comparison of GFR Calculated by Cockcroft-Gault vs. MDRD Formula in the Prognostic Assessment of Patients with Acute Pulmonary Embolism

Introduction

Risk stratification is mandatory for optimal management of patients with acute pulmonary embolism (APE). Previous studies indicated that renal dysfunction predicts outcome and can improve risk assessment in APE.

Aim

The aim of the study was a comparison of estimated glomerular filtration rate (eGFR) formulas, MDRD, and Cockcroft-Gault (CG), in the prognostic assessment of patients with APE.

Materials and Methods

Data from 2274 (1147 M/1127 F, median 71 years) hospitalised patients with APE prospectively included in a multicenter, observational, cohort study were analysed. A serum creatinine measurement as a routine laboratory parameter at the cooperating centers and eGFR calculation were performed on admission. Patients were followed for 180 days. The primary outcome was death from any cause within 30 days.

Results

The eGFR levels assessed by both, MDRD (eGFR_MDRD) and CG formula (eGFR_CG), were highest in patients with low-risk APE and lowest in high-risk APE. The eGFR (using both methods) was significantly lower in nonsurvivors compared to survivors. Using a threshold of <60 ml/min/1.73 m², eGFR_MDRD revealed the primary outcome with sensitivity 67%, specificity 52%, PPV 8%, and NPV 97%, while eGFR_CG had a sensitivity 62%, specificity 62%, PPV 8.6%, and NPV 96%. The area under the ROC curve for eGFR_CG tended to be higher than that for eGFR_MDRD: 0.658 (95% CI: 0.608-0.709) vs. 0.631 (95% CI: 0.578-0.683), p = 0.12. A subanalysis of ROC curves in a population above 65 yrs showed a higher AUC for eGFR_CG than based on MDRD. Kaplan-Meier analysis showed a worse long-term outcome in patients with impaired renal function.

Conclusion

eGFR_MDRD and eGFR_CG assessed on admission significant short- and long-term mortality predictors in patients with APE. The eGFR_CG seems to be a slightly better 30-day mortality predictor than eGFR_MDRD in the elderly.

Development and validation of a prognostic tool: Pulmonary embolism short-term clinical outcomes risk estimation (PE-SCORE)

OBJECTIVE

Develop and validate a prognostic model for clinical deterioration or death within days of pulmonary embolism (PE) diagnosis using point-of-care criteria.

METHODS

We used prospective registry data from six emergency departments. The primary composite outcome was death or deterioration (respiratory failure, cardiac arrest, new dysrhythmia, sustained hypotension, and rescue reperfusion intervention) within 5 days. Candidate predictors included laboratory and imaging right ventricle (RV) assessments. The prognostic model was developed from 935 PE patients. Univariable analysis of 138 candidate variables was followed by penalized and standard logistic regression on 26 retained variables, and then tested with a validation database (N = 801).

RESULTS

Logistic regression yielded a nine-variable model, then simplified to a nine-point tool (PE-SCORE): one point each for abnormal RV by echocardiography, abnormal RV by computed tomography, systolic blood pressure < 100 mmHg, dysrhythmia, suspected/confirmed systemic infection, syncope, medico-social admission reason, abnormal heart rate, and two points for creatinine greater than 2.0 mg/dL. In the development database, 22.4% had the primary outcome. Prognostic accuracy of logistic regression model versus PE-SCORE model: 0.83 (0.80, 0.86) vs. 0.78 (0.75, 0.82) using area under the curve (AUC) and 0.61 (0.57, 0.64) vs. 0.50 (0.39, 0.60) using precision-recall curve (AUCpr). In the validation database, 26.6% had the primary outcome. PE-SCORE had AUC 0.77 (0.73, 0.81) and AUCpr 0.63 (0.43, 0.81). As points increased, outcome proportions increased: a score of zero had 2% outcome, whereas scores of six and above had ≥ 69.6% outcomes. In the validation dataset, PE-SCORE zero had 8% outcome [no deaths], whereas all patients with PE-SCORE of six and above had the primary outcome.

CONCLUSIONS

PE-SCORE model identifies PE patients at low- and high-risk for deterioration and may help guide decisions about early outpatient management versus need for hospital-based monitoring.

Right ventricle assessment in patients with pulmonary embolism at low risk for death based on clinical models: an individual patient data meta-analysis

AIMS

Patients with acute pulmonary embolism (PE) at low risk for short-term death are candidates for home treatment or short-hospital stay. We aimed at determining whether the assessment of right ventricle dysfunction (RVD) or elevated troponin improves identification of low-risk patients over clinical models alone.

METHODS AND RESULTS

Individual patient data meta-analysis of studies assessing the relationship between RVD or elevated troponin and short-term mortality in patients with acute PE at low risk for death based on clinical models (Pulmonary Embolism Severity Index, simplified Pulmonary Embolism Severity Index or Hestia). The primary study outcome was short-term death defined as death occurring in hospital or within 30 days. Individual data of 5010 low-risk patients from 18 studies were pooled. Short-term mortality was 0.7% [95% confidence interval (CI) 0.4-1.3]. RVD at echocardiography, computed tomography or B-type natriuretic peptide (BNP)/N-terminal pro BNP (NT-proBNP) was associated with increased risk for short-term death (1.5 vs. 0.3%; OR 4.81, 95% CI 1.98-11.68), death within 3 months (1.6 vs. 0.4%; OR 4.03, 95% CI 2.01-8.08), and PE-related death (1.1 vs. 0.04%; OR 22.9, 95% CI 2.89-181). Elevated troponin was associated with short-term death (OR 2.78, 95% CI 1.06-7.26) and death within 3 months (OR 3.68, 95% CI 1.75-7.74).

CONCLUSION

RVD assessed by echocardiography, computed tomography, or elevated BNP/NT-proBNP levels and increased troponin are associated with short-term death in patients with acute PE at low risk based on clinical models. RVD assessment, mainly by BNP/NT-proBNP or echocardiography, should be considered to improve identification of low-risk patients that may be candidates for outpatient management or short hospital stay.

Risk Stratification in Acute Pulmonary Embolism: The Latest Algorithms

Pulmonary embolism (PE) is a common clinical entity, which most clinicians will encounter. Appropriate risk stratification of patients is key to identify those who may benefit from reperfusion therapy. The first step in risk assessment should be the identification of hemodynamic instability and, if present, urgent patient consideration for systemic thrombolytics. In the absence of shock, there is a plethora of imaging studies, biochemical markers, and clinical scores that can be used to further assess the patients' short-term mortality risk. Integrated prediction models incorporate more information toward an individualized and precise mortality prediction. Additionally, bleeding risk scores should be utilized prior to initiation of anticoagulation and/or reperfusion therapy administration. Here, we review the latest algorithms for a comprehensive risk stratification of the patient with acute PE.

Does kidney function matter in pulmonary thromboembolism management?

Cardiovascular circulation and kidney function are closely interrelated. The impairment of renal function is a well-known hazard of increased mortality and morbidity of patients with heart failure or coronary artery disease. Acute pulmonary embolism (APE) impacts pulmonary and systemic circulation, and can severely impair functions of other organs, including kidneys, as a result of hypoxemia and increased venous pressure. Previous studies indicate that renal dysfunction predicts short- and long-term outcomes and can improve the risk assessment in APE. However, renal function should also be cautiously considered during the diagnostic workup because the contrast-induced nephropathy after computed tomography pulmonary angiography is noticed more frequently in APE. Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare but imminent complication of APE. This condition promotes renal impairment by increasing venous pressure and decreasing glomerular filtration. The renal function improvement and serum creatinine concentration reduction were noted in CTEPH subgroup with glomerular filtration rate ≤ 60 mL/min/1.73 m2 after successful treatment. In this review, we present the essential research results on the kidney function in thromboembolism disease.

Implications of Abnormal Troponin Levels With Normal Right Ventricular Function in Normotensive Patients With Acute Pulmonary Embolism

Among patients with pulmonary embolism (PE), various permutations of normal or abnormal cardiac troponin results and normal or abnormal echocardiographic right ventricular function are encountered in clinical practice. We aimed to explore whether there is a true gradient of risk based on troponin and echocardiographic results. This study included normotensive patients with PE from the PROgnosTic valuE of CT scan in hemodynamically stable patients with acute symptomatic pulmonary embolism (PROTECT) study. Patients were categorized as having -Troponin/-Echo, -Troponin/+Echo, +Troponin/-Echo, and +Troponin/+Echo. The primary outcome was 30-day “complicated course,” including death from any cause, hemodynamic collapse, or recurrent PE. Secondary outcomes included individual adverse event rates. Of the 834 patients who had echocardiographic and troponin results, 569 patients (68%) had -Troponin/-Echo, 126 patients (15%) had -Troponin/+Echo, 74 patients (8.9%) had +Troponin/-Echo, and 65 patients (7.8%) had +Troponin/+Echo. The incidence of 30-day complicated course was 4.6% in patients with -Troponin/-Echo, 11.9% in patients with -Troponin/+Echo, 13.5% in patients with +Troponin/-Echo, and 16.9% in patients with +Troponin/+Echo (P for trend <0.001). In the subgroup of patients with a high-risk sPESI (i.e., intermediate-risk according to the ESC guidelines) (n = 527), the incidence of 30-day complicated course was 14.9% in patients with -Troponin/+Echo, 18.5% in patients with +Troponin/-Echo, and 17.5% in patients with +Troponin/+Echo (P for trend <0.01). In patiens with PE, there seems to be a risk gradient based on troponin and echocardiographic results. This study did not detect a significant risk difference in those with +Troponin/-Echo compared with -Troponin/+Echo.

Outpatient treatment of pulmonary embolism

Over the past decade there has been an increasing trend to manage many conditions traditionally treated during a hospital admission as outpatients. Evidence is increasing to support this approach in patients with pulmonary embolism (PE). In this article, we review the current status of outpatient management of confirmed PE and present a pragmatic approach for clinical healthcare settings.

Outpatient management of pulmonary embolism should be considered in all eligible patients to prevent unnecessary hospital admissions and improve quality of carehttps://bit.ly/3mo5TX7

Prognostic significance of computed tomography-assessed right ventricular enlargement in low-risk patients with pulmonary embolism: Systematic review and meta-analysis

BACKGROUND

For patients with acute low-risk pulmonary embolism (PE), determined by a validated clinical prognostic score, the additive prognostic significance of computed tomography (CT)-assessed right ventricular (RV) enlargement is uncertain.

METHODS

We performed a systematic review and meta-analysis of studies that enrolled patients with acute low-risk PE to assess the prognostic value of concomitant CT-assessed RV enlargement for 30-day all-cause mortality and PE-related death. We conducted unrestricted searches of PubMed and Embase through December 2019. We used a random-effects model to pool study results; Begg rank correlation method to evaluate for publication bias; and I² testing to assess for heterogeneity.

RESULTS

Of the 7 cohorts with 2197 participants who had low-risk PE and provided results on the primary outcome, 743 (34%; 95% confidence interval [CI], 32-36%) patients had concomitant RV enlargement. Six of 743 (0.8%; 95% CI, 0.3-1.8%) patients with concomitant RV enlargement died 30-days after the diagnosis of PE compared with 3 of 1454 (0.2%, 95% CI, 0-0.6%) without RV enlargement. CT-assessed RV enlargement did not have a significant association with 30-day all-cause mortality (odds ratio [OR], 2.6; 95% CI, 0.7-9.4; I² = 0%; P = 0.15) or PE-related mortality (OR, 2.8; 95% CI, 0.7-12.1; I² = 0%; P = 0.16).

CONCLUSIONS

CT-assessed RV enlargement occurs in a third of PE patients identified as low-risk by clinical scores. Mortality rate in these patients is low, and CT-assessed RV enlargement was not associated with a significantly increased risk of death within 30 days of PE diagnosis.

Opinion and practice survey about the use of prognostic models in acute pulmonary embolism

INTRODUCTION

Methods for prognosis assessment and patient management in acute pulmonary embolism (PE) are much debated among physicians. We conducted an online survey to determine physician's attitudes and barriers towards the use of prognostic models when treating patients with acute PE.

METHOD

Physicians members of the French and the European scientific societies for emergency medicine or of a French thrombosis research network were reached by their respective scientific societies and invited to participate via email. The questionnaire was a mixture of close-ended with yes-no or multiple-choice options and a small number of open-ended questions.

RESULTS

The survey included 461 respondents. The most commonly used prognostic tools were clinical judgment (36%) and prognostic models (29.5%). Prognostic models were used by 57% of respondents in more than half of all cases and prognostic indicators by 62% in addition to prognostic models. Affiliation group and type of hospital emerged as independent predictors for choosing prognostic models. Many (52%) reported lack of familiarity with the models and reported clinical judgment (60%) or hospital checklists (73%) as being as good as or better than prognostic models. The highest acceptable 30-day mortality rate limit for early discharge or outpatient management was deemed to be 1%, but few patients are discharged early or completely managed on an outpatient basis.

CONCLUSIONS

This survey provides new information for implementing knowledge translation strategies to improve prognostic risk assessment for acute PE patients, and highlights the need for considering the use of clinical judgment and hospital checklists in future clinical research.

Reasons for Hospitalization of Patients with Acute Pulmonary Embolism Based on the Hestia Decision Rule

Background The Hestia criteria can be used to select pulmonary embolism (PE) patients for outpatient treatment. The subjective Hestia criterion “medical/social reason for admission” allows the treating physician to consider any patient-specific circumstances in the final management decision. It is unknown how often and why this criterion is scored.

Methods This is a patient-level post hoc analysis of the combined Hestia and Vesta studies. The main outcomes were the frequency of all scored Hestia items in hospitalized patients and the explicit reason for scoring the subjective criterion. Hemodynamic parameters and computed tomography-assessed right ventricular (RV)/left ventricular (LV) ratio of those only awarded with the subjective criterion were compared with patients treated at home.

Results From the 1,166 patients screened, data were available for all 600 who were hospitalized. Most were hospitalized to receive oxygen therapy (45%); 227 (38%) were only awarded with the subjective criterion, of whom 51 because of “intermediate to intermediate-high risk PE.” Compared with patients with intermediate risk PE (RV/LV ratio > 1.0) treated at home (179/566, 32%), hospitalized patients with only the subjective criterion had a higher mean RV/LV ratio (mean difference +0.30, 95% confidence interval [CI] 0.19–0.41) and a higher heart rate (+18/min, 95% CI 10–25). No relevant differences were observed for other hemodynamic parameters.

Conclusion The most frequent reason for hospital admission was oxygen therapy. In the decision to award the subjective criterion as sole argument for admission, the severity of the RV overload and resulting hemodynamic response of the patient was taken into account rather than just abnormal RV/LV ratio.

Home treatment of venous thromboembolism disease

Despite the potential benefits of outpatient care, most patients with pulmonary embolisms are treated in hospitals for fear of possible adverse events. However, there is a wealth of scientific evidence from studies covering more than 4000 outpatients, which has led the current clinical practice guidelines to recommend early discharge or outpatient treatment when a low risk of death or complications has been confirmed, when there are no comorbidities or aggravating processes present to warrant hospitalisation and when appropriate monitoring and treatment are observed. This approach minimises the complications that can arise in hospitals and represents considerable cost savings. When selecting these patients, the use of prognostic tools such as the Pulmonary Embolism Severity Index (PESI), its simplified version (sPESI) and the Hestia Criteria are of paramount importance. Using these tools, the short-term outcomes (30-90days) show low mortality (in general <3%) and a low incidence of other complications (rate of recurrence and major bleeding <2%). Based on the available evidence, outpatient treatment can be considered the most appropriate strategy at this time for most hemodynamically stable patients with pulmonary embolisms.

Assessment of the Bova score for risk stratification of acute normotensive pulmonary embolism: A systematic review and meta-analysis

BACKGROUND

Identification of normotensive pulmonary embolism (PE) at high risk of early adverse outcome is crucial for guiding treatment. Studies showed the Bova score had promising performance in stratifying normotensive PE.

METHODS

We conducted a systematic review and meta-analysis to evaluate the prognostic performance of the Bova score for normotensive PE.

RESULTS

Nine studies involving 8342 acute normotensive PE patients were enrolled. Overall, 71.4%, 20.2% and 8.4% patients were stratified as risk class I, II and III. Pooled incidence of short-term PE related composite adverse outcome of each group were 3.8%, 10.8% and 19.9%, respectively, exhibiting a significant rising trend. Increasing trends of 30-day and in-hospital composite adverse outcome rates, as well as PE related mortality, were also observed with upper risk classes. Compared with risk class I and II, high risk group (class III) was significantly associated with short-term PE related composite adverse outcome (OR: 5.45, 95% CI, 3.70-8.02) and PE related death (OR: 5.09, 95% CI, 3.54-7.30). Pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of the score for predicting short-term composite adverse outcome were 0.25 (95% CI, 0.22-0.29), 0.93 (95% CI, 0.92-0.93), 4.05 (95% CI, 2.90-5.67) and 0.81 (95% CI, 0.74-0.88), respectively. The weighted area under the summarized receiver characteristics operation curve for predicting composite adverse outcome was 0.73 ± 0.09.

CONCLUSION

The Bova score could effectively discriminate normotensive PE with different short-term prognosis and has good performance in identifying patients at higher risk of short-term adverse events.

Development and Evaluation of a Pharmacist-Driven Screening Tool to Identify Patients Presenting to the Emergency Department Who Are Eligible for Outpatient Treatment of Deep Vein Thrombosis

BACKGROUND

Deep vein thrombosis (DVT) is a critical and costly health issue. Treatment in the outpatient setting is preferred compared to the inpatient setting. However, there is a lack of evidence regarding how best to identify patients who are ideal for outpatient DVT treatment.

OBJECTIVE

To design and evaluate a pharmacist-driven screening tool for the identification of patients presenting to the emergency department (ED) at a community hospital with DVT who are appropriate for outpatient treatment.

METHODS

This study was conducted in sequential phases: compilation and vetting of screening criteria, descriptive evaluation of criteria through retrospective chart review, and quantification of potential cost savings by avoiding admissions. Criteria were collected via literature search and assembled into a screening tool, which was applied retroactively to a cohort of ED patients admitted with DVT diagnosis.

RESULTS

A screening tool was developed with multidisciplinary input and consisted of 5 categories with individual patient and disease state criteria. The majority (91%) of patients reviewed would not have qualified for outpatient DVT treatment based on the retrospective application of the screening tool. The most common disqualification criteria category was high risk of bleeding/clotting (n = 81), and the most frequently represented parameter within that category was antithrombotic therapy prior to admission (n = 53).

CONCLUSION

A screening tool may not be the most efficient method for health-care practitioners such as pharmacists to identify ED patients appropriate for outpatient management of DVT. Other avenues should be explored for improving the cost-effective management of these patients.

Pearls and Myths in the Evaluation of Patients with Suspected Acute Pulmonary Embolism

Significant improvement has been achieved in diagnostic accuracy, validation of probability scores, and standardized treatment algorithms for patients with suspected acute pulmonary embolism. These developments have provided the tools for a safe and cost-effective management for most of these patients. In our experience, however, the presence of medical myths and ongoing controversies seem to hinder the implementation of these tools in everyday clinical practice. This review provides a selection of such dilemmas and controversies and discusses the published evidence beyond them. By doing so, we try to overcome these dilemmas and suggest pragmatic approaches guided by the available evidence and current guidelines.

Management of Low-Risk Pulmonary Embolism

Pulmonary embolism remains a leading cause of morbidity and mortality in the United States. However, with improved recognition and diagnosis, the risk of death diminishes. The diagnosis depends on the clinician's suspicion. Pulmonary emboli are categorized into low, intermediate, or high risk based on the scoring scales and patients' hemodynamic stability versus instability. Imaging plus biomarkers help stratify patients according to risk. With the advent of the computed tomography multidetector scanners, the improved imaging has increased the detection of subsegmental and incidental pulmonary emboli. Treatment of low-risk as well as subsegmental and incidental pulmonary embolism is evolving.

Acute pulmonary embolism

Pulmonary embolism, despite being common, often remains elusive as a diagnosis, and clinical suspicion needs to remain high when seeing a patient with cardiopulmonary symptoms. Once suspected, diagnosis is usually straightforward; however, optimal treatment can be difficult. Risk stratification with clinical scores, biomarkers and imaging helps to refine the best treatment strategy, but the position of thrombolysis in intermediate risk (submassive) pulmonary embolism remains a grey area. Pulmonary embolism response teams are on the increase to provide advice in such cases. Direct oral anticoagulants have been a major advance in treatment this decade, but are not appropriate for all patients. Follow-up of patients with pulmonary embolism should be mandatory to determine duration of anticoagulation and to assess for serious long-term complications.

Reducing the hospital burden associated with the treatment of pulmonary embolism

Pulmonary embolism (PE) is the most feared clinical presentation of venous thromboembolism (VTE). Patients with PE have traditionally been treated in hospital; however, many are at low risk of adverse outcomes and current guidelines suggest outpatient treatment as an option. Outpatient treatment of PE offers several advantages, including reduced risk of hospital-acquired conditions and potential cost savings. Despite this, patients with low-risk PE are still frequently hospitalized for treatment. This narrative review summarizes current guideline recommendations for the identification of patients with low-risk PE who are potentially suitable for outpatient treatment, using prognostic assessment tools (e.g. the Pulmonary Embolism Severity Index [PESI] and simplified PESI) and clinical exclusion criteria (e.g. Hestia criteria) alone or in combination with additional cardiac assessments. Treatment options are discussed along with recommendations for the follow-up of patients managed in the non-hospital environment. The available data on outpatient treatment of PE are summarized, including details on patient selection, anticoagulant choice, and short-term outcomes in each study. Accumulating evidence suggests that outcomes in patients with low-risk PE treated as outpatients are at least as good as, if not better than, those of patients treated in the hospital. With mounting pressures on health care systems worldwide, increasing the proportion of patients with PE treated as outpatients has the potential to reduce health care burdens associated with VTE.

Prognostic value of right ventricular dysfunction or elevated cardiac biomarkers in patients with low-risk pulmonary embolism: a systematic review and meta-analysis

AIMS

Patients with acute pulmonary embolism (PE) classified as low risk by the Pulmonary Embolism Severity Index (PESI), its simplified version (sPESI), or the Hestia criteria may be considered for early discharge. We investigated whether the presence of right ventricular (RV) dysfunction may aggravate the early prognosis of these patients.

METHODS AND RESULTS

We did a systematic review and meta-analysis of studies including low-risk patients with acute PE to investigate the prognostic value of RV dysfunction. Diagnosis of RV dysfunction was based on echocardiography or computed tomography pulmonary angiography. In addition, we investigated the prognostic value of elevated troponin or natriuretic peptide levels. The primary outcome was all-cause mortality at 30 days or during hospitalization. We included 22 studies (N = 3295 low-risk patients) in the systematic review: 21 were selected for quantitative analysis. Early all-cause mortality rates in patients with vs. without RV dysfunction on imaging were 1.8% [95% confidence interval (CI) 0.9-3.5%] vs. 0.2% (95% CI 0.03-1.7%), respectively, [odds ratio (OR) 4.19, 95% CI 1.39-12.58]. For troponins, rates were 3.8% (95% CI 2.1-6.8%) vs. 0.5% (95% CI 0.2-1.3%), (OR 6.25, 95% CI 1.95-20.05). For natriuretic peptides, only data on early PE-related mortality were available: rates were 1.7% (95% CI 0.4-6.9%) vs. 0.4% (95% CI 0.1-1.1%), (OR 3.71, 95% CI 0.81-17.02).

CONCLUSIONS

In low-risk patients with acute PE, the presence of RV dysfunction on admission was associated with early mortality. Our results may have implications for the management of patients who appear at low risk based on clinical criteria alone, but present with RV dysfunction as indicated by imaging findings or laboratory markers.

Emergency Department Discharge of Pulmonary Embolus Patients

Background

Hospitalization for low‐risk pulmonary embolism (PE) is common, expensive, and of questionable benefit.

Objective

The objective was to determine if low‐risk PE patients discharged from the emergency department (ED) on rivaroxaban require fewer hospital days compared to standard of care (SOC).

Methods

Multicenter, open‐label randomized trial in low‐risk PE defined by Hestia criteria. Adult subjects were randomized to early ED discharge on rivaroxaban or SOC. Primary outcome was total number of initial hospital hours, plus hours of hospitalization for bleeding or venous thromboembolism (VTE), 30 days after randomization. A 90‐day composite safety endpoint was defined as major bleeding, clinically relevant nonmajor bleeding, and mortality.

Results

Of 114 randomized subjects, 51 were early discharge and 63 were SOC. Of 112 (98.2%) receiving at least one dose of study drug, 99 (86.8%) completed the study. Initial hospital LOS was 4.8 hours versus 33.6 hours, with a mean difference of –28.8 hours (95% confidence interval [CI] = –42.55 to –15.12 hours) for early discharge versus SOC, respectively. At 90 days, mean total hospital days (for any reason) were less for early discharge than SOC, 19.2 hours versus 43.2 hours, with a mean difference of 26.4 hours (95% CI = –46.97 to –3.34 hours). At 90 days, there were no bleeding events, recurrent VTE, or deaths. The composite safety endpoint was similar in both groups, with a difference in proportions of 0.005 (95% CI = –0.18 to 0.19). Total costs were $1,496 for early discharge and $4,234 for SOC, with a median difference of $2,496 (95% CI = –$2,999 to –$2,151).

Conclusions

Low‐risk ED PE patients receiving early discharge on rivaroxaban have similar outcomes to SOC, but fewer total hospital days and lower costs over 30 days.

Implementation and Preliminary Clinical Outcomes of a Pharmacist-managed Venous Thromboembolism Clinic for Patients Treated With Rivaroxaban Post Emergency Department Discharge

OBJECTIVE

The objective was to describe the implementation, work flow, and differences in outcomes between a pharmacist-managed clinic for the outpatient treatment of venous thromboembolism (VTE) using a non-vitamin K oral anticoagulant versus care by a primary care provider (PCP).

METHODS

Patients in the studied health system that are diagnosed with low-risk VTE in the emergency department are often discharged without hospital admission. These patients are treated with a non-vitamin K oral anticoagulant and follow-up either in a pharmacist-managed VTE clinic or with their PCP. Pharmacists in the VTE clinic work independently under a collaborative practice agreement (CPA). An evaluation of 34 patients, 17 in each treatment arm, was conducted to compare the differences in treatment-related outcomes of rivaroxaban when managed by a pharmacist versus a PCP.

RESULTS

The primary endpoint was a 6-month composite of anticoagulation treatment-related complications that included a diagnosis of major bleeding, recurrent thromboembolism, or fatality due to either major bleeding or recurrent thromboembolism. Secondary endpoints included number of hospitalizations, adverse events, and medication adherence. There was no difference in the primary endpoint between groups with one occurrence of the composite endpoint in each treatment arm (p = 1.000), both of which were recurrent thromboembolic events. Medication adherence assessment was formally performed in eight patients in the pharmacist group versus no patients in the control group. No differences were seen among other secondary endpoints.

CONCLUSIONS

The pharmacist-managed clinic is a novel expansion of clinical pharmacy services that treats patients with low-risk VTEs with rivaroxaban in the outpatient setting. The evaluation of outcomes provides support that pharmacist-managed care utilizing standardized protocols under a CPA may be as safe as care by a PCP.

The diagnosis and treatment of venous thromboembolism in asian patients

Although the incidence of venous thromboembolism (VTE) in Asian populations is lower than in Western countries, the overall burden of VTE in Asia has been considerably underestimated. Factors that may explain the lower prevalence of VTE in Asian populations relative to Western populations include the limited availability of epidemiological data in Asia, ethnic differences in the genetic predisposition to VTE, underdiagnoses, low awareness toward thrombotic disease, and possibly less symptomatic VTE in Asian patients. The clinical assessment, diagnostic testing, and therapeutic considerations for VTE are, in general, the same in Asian populations as they are in Western populations. The management of VTE is based upon balancing the treatment benefits against the risk of bleeding. This is an especially important consideration for Asian populations because of increased risk of intracranial hemorrhage with vitamin K antagonists. Non-vitamin K antagonist oral anticoagulants have shown advantages over current treatment modalities with respect to bleeding outcomes in major phase 3 clinical trials, including in Asian populations. Although anticoagulant therapy has been shown to reduce the risk of postoperative VTE in Western populations, VTE prophylaxis is not administered routinely in Asian countries. Despite advances in the management of VTE, data in Asian populations on the incidence, prevalence, recurrence, risk factors, and management of bleeding complications are limited and there is need for increased awareness. To that end, this review summarizes the available data on the epidemiology, risk stratification, diagnosis, and treatment considerations in the management of VTE in Asia.

Direct oral anticoagulants in the treatment of pulmonary embolism

OBJECTIVE

The objective of this review is to examine the management strategies for pulmonary embolism (PE) with an emphasis of the role of direct oral anticoagulants (DOACs).

METHODS

PubMed was searched to identify relevant journal articles published through April 2017. Additional references were obtained from articles discovered during the database search.

RESULTS

Initial heparinization followed by long-term anticoagulation with vitamin K antagonists has been considered the mainstay for the treatment of PE. However, DOACs now offer comparably effective and potentially safer alternatives for both acute and long-term treatment of PE using a monotherapy approach without the need for initial heparinization for rivaroxaban or apixaban. Advantages to using DOACs include oral availability, rapid onset of action, minimal drug and food interactions, predictable pharmacokinetics, and lack of need for routine monitoring. Limitations of using these agents include a limited availability of assays to quickly and efficiently measure their anticoagulant effects and the lack of widely available reversal agents for the direct oral factor Xa inhibitors; although idarucizumab has recently been approved for the reversal of dabigatran's anticoagulant effects.

CONCLUSIONS

Advantages to using DOACs render them an attractive alternative to conventional therapy in PE treatment that may simplify acute and long-term treatment paradigms, improve patient outcomes, and increase patient compliance. However, questions remain pertaining to the use of DOACs in PE patients with high-risk features and in cancer patients and fragile populations. Clinical studies are under way to address many of these issues.

Prognostic value of right ventricular dilatation in patients with low-risk pulmonary embolism

The prognosis of multidetector computed tomography (MDCT) assessed right ventricular dilatation (RVD) is unclear in patients with pulmonary embolism (PE) and a simplified Pulmonary Embolism Severity Index (sPESI) of 0. We investigated in these patients whether MDCT-assessed RVD, defined by a right to left ventricular ratio (RV/LV) ≥0.9 or ≥1.0, is associated with worse outcomes.

We combined data from three prospective cohorts of patients with PE. The main study outcome was the composite of 30-day all-cause mortality, haemodynamic collapse or recurrent PE in patients with sPESI of 0.

Among 779 patients with a sPESI 0, 420 (54%) and 299 (38%) had a RV/LV ≥0.9 and ≥1.0 respectively. No difference in primary outcome was observed, 0.95% (95% CI 0.31–2.59) versus 0.56% (95% CI 0.10–2.22; p=0.692) and 1.34% (95% CI 0.43–3.62) versus 0.42% (95% CI 0.07–1.67; p=0.211) with RV/LV ≥0.9 and ≥1.0 respectively. Increasing the RV/LV threshold to ≥1.1, the outcome occurred more often in patients with RVD (2.12%, 95% CI 0.68–5.68 versus 0.34%, 95% CI 0.06–1.36; p=0.033).

MDCT RV/LV ratio of ≥0.9 and ≥1.0 in sPESI 0 patients is frequent but not associated with a worse prognosis but higher cut-off values might be associated with worse outcome in these patients.

Outpatient Management in Patients with Venous Thromboembolism with Edoxaban: A Post Hoc Analysis of the Hokusai-VTE Study

Direct oral anticoagulants (DOACs) facilitate the outpatient treatment of venous thromboembolism (VTE). However, the pivotal trials of DOACs have not reported outcomes separately for patients managed either as outpatients or in the hospital. We performed a subgroup analysis of the Hokusai-VTE study comparing efficacy and safety of edoxaban with warfarin in 8,292 patients with acute VTE. Patients received initial therapy with open-label enoxaparin or unfractionated heparin for ≥5 days in the hospital or as an outpatient at the discretion of the treating physician. Edoxaban or warfarin was then given for 3 to 12 months. The primary efficacy outcome was the cumulative incidence of symptomatic recurrent VTE at 12 months. The principal safety outcome was the incidence of clinically relevant bleeding (composite of major or clinically relevant non-major bleeding). Of the 5,223 consecutively enrolled patients with recorded hospital status and length of stay, 1,414 patients (27.1%) were managed as outpatients and 3,809 were managed in hospital. Among the outpatients, initial presentation was symptomatic deep-vein thrombosis (DVT) in 1,183 patients (83.7%) and pulmonary embolism (PE) in 231 patients (16.3%). Among the outpatients with DVT, recurrent VTE occurred in 18 (3.0%) given edoxaban and in 21 (3.6%) given warfarin (risk difference: −0.61, 95% confidence interval [CI]: −2.6 to 1.4). The principal safety outcome in outpatients occurred in 46 edoxaban patients (7.7%) and in 48 warfarin patients (8.3%; risk difference: −0.59, 95% CI: −3.7 to 2.5). Most outpatients had symptomatic DVT at presentation. In these patients, initial heparin followed by edoxaban had similar efficacy and safety to standard therapy with heparin and warfarin.

Update on the risk stratification of acute symptomatic pulmonary thromboembolism

Early mortality in patients with pulmonary thromboembolism (PTE) varies from 2% in normotensive patients to 30% in patients with cardiogenic shock. The current risk stratification for symptomatic PTE includes 4 patient groups, and the recommended therapeutic strategies are based on this stratification. Patients who have haemodynamic instability are considered at high risk. Fibrinolytic treatment is recommended for these patients. In normotensive patients, risk stratification helps differentiate between those of low risk, intermediate-low risk and intermediate-high risk. There is currently insufficient evidence on the benefit of intensive monitoring and fibrinolytic treatment in patients with intermediate-high risk. For low-risk patients, standard anticoagulation is indicated. Early discharge with outpatient management may be considered, although its benefit has still not been firmly established.

Is oxygen saturation variable of simplified pulmonary embolism severity index reliable for identification of patients, suitable for outpatient treatment

INTRODUCTION

The pulmonary embolism severity index (PESI) or simplified version (sPESI) are widely validated risk scores for the identification of eligible patients for outpatient treatment. Saturation is one of these criteria. For this metric, saturation of 90% or greater is assigned zero points. However, 90% saturation does not always exclude hypoxemic respiratory failure.

OBJECTIVE

The aims of this study were first was to define corresponding partial arterial oxygen pressure (PaO₂ ) values according to saturation in pulmonary embolism (PE) patients, and the second was to define a target saturation that can exclude hypoxemic respiratory failure and enable secure discharge of PE patients from emergency departments.

METHODS

This is a retrospective study. To determine the optimal saturation value by which to detect hypoxemic respiratory failure, we generated receiver operating characteristic (ROC) curves and calculated the negative predictive value.

RESULTS

Total of 65 patients were included in this study. Mean PaO₂ levels from SaO₂ 89% to SaO₂ 93% were 52.8, 57.1, 57.3, 61, and 63.8 mmHg, respectively. ROC curve analysis revealed SaO₂ level of 91.5% to be optimal target saturation for excluding respiratory failure with 84.6% specificity and 89.7% sensitivity; area under the curve was 0.885 (95% CI 0.796-0.975). The negative predictive value was 80% for SaO₂ level of 92%.

CONCLUSION

Patients with PE may be in respiratory failure despite an oxyhemoglobin saturation of ≥90%. Although saturation is likely more important than precise PaO₂ in tissue oxygenation, clinicians should be aware of the physiological effects of hypoxemia and take this into account before making outpatient treatment decisions.

Best Clinical Practice: Controversies in Outpatient Management of Acute Pulmonary Embolism

BACKGROUND

Pulmonary embolism (PE) is a common condition managed in the emergency department (ED), with a wide range of morbidity and mortality. Patients are classically admitted for treatment and monitoring of anticoagulation.

OBJECTIVE

We sought to evaluate the controversy concerning outpatient therapy for patients with acute PE and investigate the feasibility, safety, and efficacy of outpatient management.

DISCUSSION

Patients with venous thromboembolism have historically been admitted for treatment and monitoring for concern of worsening disease or side effects of anticoagulation (bleeding). More than 90% of EDs admit patients with PE in the United States. However, close to 50% of patients may be appropriate for discharge and outpatient therapy. The published literature suggests that outpatient treatment is safe, feasible, and efficacious, with similar rates of recurrent venous thromboembolism and all-cause mortality, especially with novel oral anticoagulants. Multiple scoring criteria can be used, including the Pulmonary Embolism Severity Index (PESI), simplified PESI, Hestia criteria, Geneva Prognostic Score, European Society of Cardiology guidelines, Global Registry of Acute Coronary Events, and Aujesky score. Simplified PESI and the European Society of Cardiology guidelines have high-quality evidence, sufficient sensitivity, and ease of use for the ED. Patients considered for outpatient therapy should possess low hemorrhage risk, adequate social situation, negative biomarkers, ability to comply, and no alternate need for admission.

CONCLUSIONS

Patients with acute PE are often admitted in the United States, but a significant proportion may be appropriate for discharge. Patients with low risk for adverse events according to clinical scoring criteria, adequate follow-up, ability to comply, and no other need for admission can be discharged with novel oral anticoagulant therapy.

The role of computed tomography in the diagnosis of acute and chronic pulmonary embolism

Pulmonary embolism (PE) is a potentially life threatening condition requiring adequate diagnosis and treatment. Computed tomography pulmonary angiography (CTPA) is excellent for including and excluding PE, therefore CT is the first-choice diagnostic imaging technique in patients suspected of having acute PE. Due to its wide availability and low invasiveness, CTPA tends to be overused. Correct implementation of clinical decision rules in diagnostic workup for PE improves adequate use of CT. Also, CT adds prognostic value by evaluating right ventricular (RV) function. CT-assessed RV dysfunction and to lesser extent central emboli location predicts PE-related mortality in normotensive and hypotensive patients, while PE embolic obstruction index has limited prognostic value. Simple RV/left ventricular (LV) diameter ratio measures >1.0 already predict risk for adverse outcome, whereas ratios <1.0 can safely exclude adverse outcome. Consequently, assessing the RV/LV diameter ratio may help identify patients who are potential candidates for treatment at home instead of treatment in the hospital. A minority of patients develop chronic thromboembolic pulmonary hypertension (CTEPH) following acute PE, which is a life-threatening condition that can be diagnosed by CT. In proximal CTEPH, involving the more central pulmonary arteries, thrombectomy usually results in good outcome in terms of both functional status and long-term survival rate. CT is becoming the imaging method of choice for diagnosing CTEPH as it can identify patients who may benefit from thrombectomy. New CT developments such as distensibility measurements and dual-energy or subtraction techniques may further refine diagnosis and prognosis for improved patient care.

Multicenter Trial of Rivaroxaban for Early Discharge of Pulmonary Embolism From the Emergency Department (MERCURY PE): Rationale and Design

OBJECTIVES

Traditionally, patients with pulmonary embolism (PE) are admitted from the emergency department and treated with low-molecular-weight heparin followed by warfarin. Several studies now demonstrate that it is possible to identify low-risk PE patients that can safely be treated as outpatients. The advent of the direct-acting oral anticoagulants such as rivaroxaban has made it easier than ever to manage patients outside of the hospital. This article describes the design of a randomized controlled trial aimed at testing the hypothesis that low-risk PE patients can be safely and effectively managed at home using rivaroxaban, resulting in fewer days of hospitalization than standard-of-care treatment.

METHODS

We have initiated a multicenter, open-label, randomized clinical trial in which low-risk adult PE patients (identified by the Hestia criteria) are randomized to outpatient management with oral rivaroxaban 15 mg twice daily for 21 days followed by 20 mg once daily for 90 days versus standard care, determined by the treating physician and based on local practices. The primary clinical endpoint will be the total number of inpatient hospital days (including the index admission) for venous thromboembolic or bleeding-related events during the first 30 days after randomization. A total of 150 subjects per group will provide 82% power to detect a difference of 1 day or greater in the primary outcome.

RESULTS

Patient enrollment is ongoing at present in 45 of 60 planned sites. No interim analysis is planned and the study is being monitored by a data safety management board.

CONCLUSIONS

The MERCURY PE study is designed to test the hypothesis that outpatient management of low-risk PE patients with rivaroxaban reduces the number of hospitalization days from venous thromboembolism and bleeding compared with standard care. This article describes the rationale and methodology for this study.

Prognostic Value of Right Ventricular Dysfunction Markers for Serious Adverse Events in Acute Normotensive Pulmonary Embolism

BACKGROUND

Right ventricular dysfunction (RVD) in pulmonary embolism (PE) has been associated with increased morbidity. Tools for RVD identification are not well defined. The prognostic value of RVD markers to predict serious adverse events (SAE) during hospitalization is unclear.

OBJECTIVE

Prospectively compare the incidence of SAE in normotensive emergency department patients with PE based upon RVD by goal-directed echocardiography (GDE), cardiac biomarkers, and right-to-left ventricle ratio by computed tomography (CT). Simplified Pulmonary Embolism Severity Index (sPESI) was calculated. Deaths and readmissions within 30 days were recorded.

METHODS

Consecutive normotensive PE patients underwent GDE focused on RVD (RV enlargement, hypokinesis, or septal bowing), serum troponin, and brain natriuretic peptide (BNP), and evaluation of the CT ventricle ratio. In-hospital SAE and complications within 30 days were recorded.

RESULTS

We enrolled 123 normotensive PE patients (median age 59 years, 49% female). Twenty-six of 123 (26%) patients had one or more SAE. RVD was detected in 26% by GDE, in 39% by biomarkers, and in 38% with CT. In-hospital SAE included one death, six respiratory interventions, six dysrhythmias, three major bleeding episodes, and 21 hypotension episodes. Forty-one percent of patients RVD positive by GDE had SAE, compared to the 18% RVD negative by GDE. Odds ratios for GDE, CT, BNP, troponin, and sPESI for SAE were 3.2 (95% confidence interval [CI] 1.2-8.5), 2.0 (95% CI 0.8-5.1), 3.3 (95% CI 1.3-8.6), 4.2 (95% CI 1.4-13.5), and 2.9 (95% CI 1.1-8.3), respectively. Five patients had non-PE-related deaths within 30 days.

CONCLUSION

The incidence of SAE within days of PE was significant in our cohort. Those with RVD had an increased risk of nonmortality SAE.

Prognostic value of computed tomography in acute pulmonary thromboembolism

In addition to being the standard reference for the diagnosis of acute pulmonary thromboembolism, CT angiography of the pulmonary arteries can also provide valuable information about the patient's prognosis. Although which imaging findings are useful for prognosis remains controversial, signs of right ventricular dysfunction on CT are now included in clinical algorithms for the management of pulmonary thromboembolism. However, the optimal method for obtaining these measurements while maintaining a balance between the ease of use necessary to include their evaluation in our daily activity and the loss of precision in its predictive capacity remains to be determined. Moreover, other variables associated with pulmonary thromboembolism that often go unobserved can complement the prognostic information we can offer to clinicians. This review aims to clarify some of the more controversial aspects related to the prognostic value of CT in patients with pulmonary embolisms according to the available evidence. Knowing which variables are becoming more important in the prognosis, how to detect them, and why it is important to include them in our reports will help improve the management of patients with pulmonary embolism.