Outpatient versus inpatient treatment for acute pulmonary embolism

Pulmonary embolism in United States emergency departments, 2010-2018

Little is known about pulmonary embolism (PE) in the United States emergency department (ED). This study aimed to describe the disease burden (visit rate and hospitalization) of PE in the ED and to investigate factors associated with its burden. Data were obtained from the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 2010 to 2018. Adult ED visits with PE were identified using the International Classification of Diseases codes. Analyses used descriptive statistics and multivariable logistic regression accounting for the NHAMCS's complex survey design. Over the 9-year study period, there were an estimated 1,500,000 ED visits for PE, and the proportion of PE visits in the entire ED population increased from 0.1% in 2010-2012 to 0.2% in 2017-2018 (P for trend = 0.002). The mean age was 57 years, and 40% were men. Older age, obesity, history of cancer, and history of venous thromboembolism were independently associated with a higher proportion of PE, whereas the Midwest region was associated with a lower proportion of PE. The utilization of chest computed tomography (CT) scan appeared stable, which was performed in approximately 43% of the visits. About 66% of PE visits were hospitalized, and the trend remained stable. Male sex, arrival during the morning shift, and higher triage levels were independently associated with a higher hospitalization rate, whereas the fall and winter months were independently associated with a lower hospitalization rate. Approximately 8.8% of PE patients were discharged with direct-acting oral anticoagulants. The ED visits for PE continued to increase despite the stable trend in CT use, suggesting a combination of prevalent and incident PE cases in the ED. Hospitalization for PE remains common practice. Some patients are disproportionately affected by PE, and certain patient and hospital factors are associated with hospitalization decisions.

Monotherapy Anticoagulation to Expedite Home Treatment of Patients Diagnosed With Venous Thromboembolism in the Emergency Department: A Pragmatic Effectiveness Trial

BACKGROUND

The objective was to test if low-risk emergency department patients with vitamin K antagonist (venous thromboembolism [VTE]; including venous thrombosis and pulmonary embolism [PE]) can be safely and effectively treated at home with direct acting oral (monotherapy) anticoagulation in a large-scale, real-world pragmatic effectiveness trial.

METHODS

This was a single-arm trial, conducted from 2016 to 2019 in accordance with the Standards for Reporting Implementation Studies guideline in 33 emergency departments in the United States. Participants had newly diagnosed VTE with low risk of death based upon either the modified Hestia criteria, or physician judgment plus the simplified PE severity index score of zero, together with nonhigh bleeding risk were eligible. Patients had to be discharged within 24 hours of triage and treated with either apixaban or rivaroxaban. Effectiveness was defined by the primary efficacy and safety outcomes, image-proven recurrent VTE and bleeding requiring hospitalization >24 hours, respectively, with an upper limit of the 95% CI for the 30-day frequency of VTE recurrence below 2.0% for both outcomes.

RESULTS

We enrolled 1421 patients with complete outcomes data, including 903 with venous thrombosis and 518 with PE. The recurrent VTE requiring hospitalization occurred in 14/1421 (1.0% [95% CI, 0.5%-1.7%]), and bleeding requiring hospitalization occurred in 12/1421 (0.8% [0.4%-1.5%). The rate of severe bleeding using International Society for Thrombosis and Haemostasis criteria was 2/1421 (0.1% [0%-0.5%]). No patient died, and serious adverse events occurred in 2.5% of venous thrombosis patients and 2.3% of patients with PE. Medication nonadherence was reported by patients in 8.0% (6.6%-9.5%) and was associated with a risk ratio of 6.0 (2.3-15.2) for VTE recurrence. Among all patients diagnosed with VTE in the emergency department during the period of study, 18% of venous thrombosis patients and 10% of patients with PE were enrolled.

CONCLUSIONS

Monotherapy treatment of low-risk patients with venous thrombosis or PE in the emergency department setting produced a low rate of bleeding and VTE recurrence, but may be underused. Patients with venous thrombosis and PE should undergo risk-stratification before home treatment. Improved patient adherence may reduce rate of recurrent VTE. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03404635.

Healthcare and Economic Impact of Lung Perfusion Scintigraphy in Patients Affected by Acute Pulmonary Embolism

Acute pulmonary embolism (APE) is a cardiovascular emergency, representing the main cause of mortality, morbidity, and hospitalisation in Europe. We aim to evaluate the economic and healthcare impact of lung perfusion scintigraphy (LPS) used in patients with suspected APE, in the event of non-conclusive or contraindicated computed tomography pulmonary angiography (CTPA). We considered two alternative healthcare processes for APE diagnosis, with and without LPS. We performed a cost analysis with the aim of evaluating the average direct healthcare costs for diagnosis, risk assessment, and treatment of APE. We used data from a monocentric trial. Our economic model showed that the strategy with LPS was preferable in terms of costs. The average per-patient costs for the diagnosis and treatment of the acute phase of PE in low-risk patients with a non-conclusive or not-executable CTPA, with and without LPS, are EUR 2145.25 and EUR 4912.45, respectively. LPS is a simple, quick, and economic examination, useful in this setting of patients not only for an early diagnosis but also to exclude APE, demonstrating an advantage in terms of healthcare resources. To the best of our knowledge, this study is the first to analyse the economic and healthcare impact of the use of LPS in the diagnostic pathway of suspected APE.

Outpatient management of patients presenting with venous thromboembolism: Retrospective cohort study at 11 community hospitals

A gap exists between clinical practice guidelines and real-world practice. We aim to investigate hospital admissions among patients presenting to emergency departments of 11 hospitals with venous thromboembolism (VTE). Eligible patients’ first emergency department VTE visit were retrospectively collected between 2013 and 2018 from electronic medical records (EMR). Patients were categorized at low risk of VTE complications if they were diagnosed with deep vein thrombosis (DVT) of the leg or if they were diagnosed with pulmonary embolism (PE) and had a PE score index < 85. Multivariable logistic regression models were constructed to measure the adjusted odds ratios (OR) and 95% confidence intervals (CI) of hospital admissions before and after clinical practice guidelines were updated to recommend outpatient management of DVT and PE with low risk of complications. A total of 13,677 patients were included in the analysis, of which 55% were diagnosed with DVT. Mean age was 65  ±  17 years, 54% were females, and 62% were Caucasian. Overall, 9281 patients were categorized at low risk VTE complications, of whom 77% were admitted for in-hospital management. The rate of in-hospital management declined from 81% in 2013 to 73% in 2018. Patients visiting emergency departments between 2016 and 2018 (post-guidelines) were equally likely to be admitted compared to patients visiting the emergency departments between 2013 and 2015 (pre-guidelines; OR = 0.99; 95% CI: 0.88, 1.11). Results from this real-world study indicate that most low-risk VTE patients are admitted for in-hospital management, despite recommendations in clinical practice guidelines.

Study protocol for a multicentre implementation trial of monotherapy anticoagulation to expedite home treatment of patients diagnosed with venous thromboembolism in the emergency department

INTRODUCTION

In the USA, many emergency departments (EDs) have established protocols to treat patients with newly diagnosed deep vein thrombosis (DVT) as outpatients. Similar treatment of patients with pulmonary embolism (PE) has been proposed, but no large-scale study has been published to evaluate a comprehensive, integrated protocol that employs monotherapy anticoagulation to treat patients diagnosed with DVT and PE in the ED.

METHODS AND ANALYSIS

This protocol describes the implementation of the Monotherapy Anticoagulation To expedite Home treatment of Venous ThromboEmbolism (MATH-VTE) study at 33 hospitals in the USA. The study was designed and executed to meet the requirements for the Standards for Reporting Implementation Studies guideline. The study was funded by investigator-initiated awards from industry, with Indiana University as the sponsor. The study principal investigator and study associates travelled to each site to provide on-site training. The protocol identically screens patients with both DVT or PE to determine low risk of death using either the modified Hestia criteria or physician judgement plus a negative result from the simplified PE severity index. Patients must be discharged from the ED within 24 hours of triage and treated with either apixaban or rivaroxaban. Overall effectiveness is based upon the primary efficacy and safety outcomes of recurrent VTE and bleeding requiring hospitalisation respectively. Target enrolment of 1300 patients was estimated with efficacy success defined as the upper limit of the 95% CI for the 30-day frequency of VTE recurrence below 2.0%. Thirty-three hospitals in 17 states were initiated in 2016-2017.

ETHICS AND DISSEMINATION

All sites had Institutional Review Board approval. We anticipate completion of enrolment in June 2020; study data will be available after peer-reviewed publication. MATH-VTE will provide information from a large multicentre sample of US patients about the efficacy and safety of home treatment of VTE with monotherapy anticoagulation.

Home vs hospital treatment of low-risk venous thromboembolism: a systematic review and meta-analysis

Increasing evidence supports the safety and effectiveness of managing low-risk deep vein thrombosis (DVT) or pulmonary embolism (PE) in outpatient settings. We performed a systematic review to assess safety and effectiveness of managing patients with DVT or PE at home compared with the hospital. Medline, Embase, and Cochrane databases were searched up to July 2019 for relevant randomized clinical trials (RCTs), and prospective cohort studies. Two investigators independently screened titles and abstracts of identified citations and extracted data from relevant full-text papers. Risk ratios (RRs) were calculated, and certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE). Seven RCTs (1922 patients) were included in meta-analyses on managing patients with DVT. Pooled estimates indicated decreased risk of PE (RR = 0.64; 95% confidence interval [CI], 0.44-0.93) and recurrent DVT (RR = 0.61; 95% CI, 0.42-0.90) for home management, both with moderate certainty of the evidence. Reductions in mortality and major bleeding were not significant, both with low certainty of the evidence. Two RCTs (445 patients) were included in meta-analyses on home management of low-risk patients with PE. Pooled estimates indicated no significant difference in all-cause mortality, recurrent PE, and major bleeding, all with low certainty of the evidence. Results of pooled estimates from 3 prospective cohort studies (234 patients) on home management of PE showed similar results. Our findings indicate that low-risk DVT patients had similar or lower risk of patient-important outcomes with home treatment compared with hospital treatment. In patients with low-risk PE, there was important uncertainty about a difference between home and hospital treatment.