Home treatment of patients with low-risk pulmonary embolism with the oral factor Xa inhibitor rivaroxaban. Rationale and design of the HoT-PE Trial

Clinical controversies in the management of acute pulmonary embolism: evaluation of four important but controversial aspects of acute pulmonary embolism management that are still subject of debate and research

INTRODUCTION

Acute pulmonary embolism (PE) is a disease with a broad spectrum of clinical presentations. While some patients can be treated at home or may even be left untreated, other patients require an aggressive approach with reperfusion treatment.

AREAS COVERED

(1) Advanced reperfusion treatment in hemodynamically stable acute PE patients considered to be at high risk of decompensation and death, (2) the treatment of subsegmental pulmonary embolism, (3) outpatient treatment for hemodynamically stable PE patients with signs of right ventricle (RV) dysfunction, and (4) the optimal approach to identify and treatpost-PE syndrome.

EXPERT OPINION

Outside clinical trials, hemodynamically stable acute PE patients should not be treated with primary reperfusion therapy. Thrombolysis and/or catheter-directed therapy are only to be considered as rescue treatment. Subsegmental PE can be left untreated in selected low-risk patients, after proximal deep vein thrombosis has been ruled out. Patients with an sPESI or Hestia score of 0 criteria can be treated at home, independent of the presence of RV overload. Finally, health-care providers should be aware of post-PE syndrome and diagnose chronic thromboembolic pulmonary disease (CTEPD) as early as possible. Persistently symptomatic patients without CTEPD benefit from exercise training and cardiopulmonary rehabilitation.

Venous thromboembolism: Recent advancement and future perspective

Clinicians have been more and more often encountering patients with venous thromboembolism (VTE), including pulmonary embolism and deep vein thrombosis, leading to the increased importance of VTE in daily clinical practice. VTE is becoming a common issue in Asian countries including Japan. The management strategies of VTE have changed dramatically in the past decade including the introduction of direct oral anticoagulants (DOACs). In addition, there have been several landmark clinical trials assessing acute treatment strategies including thrombolysis and inferior vena cava (IVC) filter. The current VTE guidelines do not recommend the routine use of thrombolysis or IVC filters based on recent evidence; Nevertheless, the prevalence of thrombolysis and IVC filter use in Japan was strikingly high. The novel profiles of DOACs with rapid onset of action and potential benefit of a lower risk for bleeding compared with vitamin K antagonist could make home treatment feasible and is safer even with extended anticoagulation therapy. One of the most clinically relevant issues for VTE treatment is optimal duration of anticoagulation for the secondary prevention of VTE. Considering recent evidence, optimal duration of anticoagulation should be determined based on the risk for recurrence as well as the risk for bleeding in an individual patient. Despite the recent advances for VTE management, there are still a number of uncertain issues that challenge clinicians in daily clinical practice, such as cancer-associated VTE and minor VTE including subsegmental pulmonary embolism and distal deep vein thrombosis, warranting future research. Several clinical trials are now ongoing for these issues, globally as well as in Japan. The current review is aimed to overview the recent advances in VTE management, describe the current status including some domestic issues in Japan, and discuss the future perspective of VTE.

Efficacy of rivaroxaban for the treatment of Chinese patients with acute pulmonary embolism: A retrospective study

Pulmonary embolism (PE) is a life-threatening disease, which accounts for the major type of venous thromboembolism. Currently, there is limited understanding and management for PE. Rivaroxaban is reported to treat patients with PE. However, there is still insufficient evidence on rivaroxaban for the treatment of Chinese patients with acute PE. Thus, this retrospective study investigated the benefits and safety of rivaroxaban for Chinese patients with acute PE.A total of 72 Chinese patient cases with acute PE were analyzed in this study. Of these, 36 cases who received rivaroxaban mono-therapy were assigned to the treatment group, while the remaining 36 cases who received standard therapy were assigned to the control group. The benefits were assessed by the duration of hospital stay, treatment satisfaction, and safety.After treatment, rivaroxaban mono-therapy showed better benefits in decreasing the duration of hospital stay (P < .01), increasing treatment satisfaction (P < .01), and reducing mild bleeding (P = .02) in Chinese patients with acute PE, than standard therapy.The results of this study indicated that rivaroxaban may provide more benefits than the standard therapy for Chinese patients with acute PE. Future studies are still needed to warrant the current results.

Early discharge and home treatment of patients with low-risk pulmonary embolism with the oral factor Xa inhibitor rivaroxaban: an international multicentre single-arm clinical trial

AIMS

To investigate the efficacy and safety of early transition from hospital to ambulatory treatment in low-risk acute PE, using the oral factor Xa inhibitor rivaroxaban.

METHODS AND RESULTS

We conducted a prospective multicentre single-arm investigator initiated and academically sponsored management trial in patients with acute low-risk PE (EudraCT Identifier 2013-001657-28). Eligibility criteria included absence of (i) haemodynamic instability, (ii) right ventricular dysfunction or intracardiac thrombi, and (iii) serious comorbidities. Up to two nights of hospital stay were permitted. Rivaroxaban was given at the approved dose for PE for ≥3 months. The primary outcome was symptomatic recurrent venous thromboembolism (VTE) or PE-related death within 3 months of enrolment. An interim analysis was planned after the first 525 patients, with prespecified early termination of the study if the null hypothesis could be rejected at the level of α = 0.004 (<6 primary outcome events). From May 2014 through June 2018, consecutive patients were enrolled in seven countries. Of the 525 patients included in the interim analysis, three (0.6%; one-sided upper 99.6% confidence interval 2.1%) suffered symptomatic non-fatal VTE recurrence, a number sufficiently low to fulfil the condition for early termination of the trial. Major bleeding occurred in 6 (1.2%) of the 519 patients comprising the safety population. There were two cancer-related deaths (0.4%).

CONCLUSION

Early discharge and home treatment with rivaroxaban is effective and safe in carefully selected patients with acute low-risk PE. The results of the present trial support the selection of appropriate patients for ambulatory treatment of PE.

Survival and quality of life after early discharge in low-risk pulmonary embolism

Introduction

Early discharge of patients with acute low-risk pulmonary embolism requires validation by prospective trials with clinical and quality-of-life outcomes.

Methods

The multinational Home Treatment of Patients with Low-Risk Pulmonary Embolism with the Oral Factor Xa Inhibitor Rivaroxaban (HoT-PE) single-arm management trial investigated early discharge followed by ambulatory treatment with rivaroxaban. The study was stopped for efficacy after the positive results of the predefined interim analysis at 50% of the planned population. The present analysis includes the entire trial population (576 patients). In addition to 3-month recurrence (primary outcome) and 1-year overall mortality, we analysed self-reported disease-specific (Pulmonary Embolism Quality of Life (PEmb-QoL) questionnaire) and generic (five-level five-dimension EuroQoL (EQ-5D-5L) scale) quality of life as well as treatment satisfaction (Anti-Clot Treatment Scale (ACTS)) after pulmonary embolism.

Results

The primary efficacy outcome occurred in three (0.5%, one-sided upper 95% CI 1.3%) patients. The 1-year mortality was 2.4%. The mean±sd PEmb-QoL decreased from 28.9±20.6% at 3 weeks to 19.9±15.4% at 3 months, a mean change (improvement) of −9.1% (p<0.0001). Improvement was consistent across all PEmb-QoL dimensions. The EQ-5D-5L was 0.89±0.12 at 3 weeks after enrolment and improved to 0.91±0.12 at 3 months (p<0.0001). Female sex and cardiopulmonary disease were associated with poorer disease-specific and generic quality of life; older age was associated with faster worsening of generic quality of life. The ACTS burden score improved from 40.5±6.6 points at 3 weeks to 42.5±5.9 points at 3 months (p<0.0001).

Conclusions

Our results further support early discharge and ambulatory oral anticoagulation for selected patients with low-risk pulmonary embolism. Targeted strategies may be necessary to further improve quality of life in specific patient subgroups.

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.

Clinical and Economic Outcomes in Low-risk Pulmonary Embolism Patients Treated with Rivaroxaban versus Standard of Care

BACKGROUND

Rivaroxaban, a fixed-dose oral direct factor Xa inhibitor, does not require continuous monitoring and thus reduces the hospital stay and economic burden in low-risk pulmonary embolism (LRPE) patients. Study Question: What is the effectiveness of rivaroxaban versus the standard of care (SOC; low-molecular-weight heparin, unfractionated heparin, warfarin) among LRPE patients in the Veterans Health Administration?

STUDY DESIGN

Adult patients with continuous health plan enrollment for ≥12 months pre- and 3 months post-inpatient PE diagnosis (index date=discharge date) between October 1, 2011-June 30, 2015 and an anticoagulant claim during the index hospitalization were included.

MEASURES AND OUTCOMES

Patients scoring 0 points on the simplified Pulmonary Embolism Stratification Index were considered low-risk and were stratified into SOC and rivaroxaban cohorts. Propensity score matching (PSM) was used to compare hospital-acquired complications (HACs), PE-related outcomes (recurrent venous thromboembolism, major bleeding, and death), and healthcare utilization and costs between the rivaroxaban and SOC cohorts.

RESULTS

Among 6746 PE patients, 1918 were low-risk; of these, 73 were prescribed rivaroxaban, 1546 were prescribed SOC, and 299 were prescribed other anticoagulants during the index hospitalization. After 1:3 PSM, 64 rivaroxaban and 192 SOC patients were included. During the index hospitalization, rivaroxaban users (versus SOC) had similar inpatient length of stay (LOS; 7.0 vs 6.7 days, standardized difference [STD]=1.8) but fewer HACs (4.7% vs 10.4%; STD: 21.7). In the 90-day post-discharge period, PE-related outcome rates were similar between the cohorts (all p>0.05). However, rivaroxaban users had fewer outpatient (15.9 vs 20.4; p=0.0002) visits per patient as well as lower inpatient ($765 vs $2,655; p<0.0001), pharmacy ($711 vs $1,086; p=0.0033), and total costs ($6,270 vs $9,671; p=0.0027).

CONCLUSIONS

LRPE patients prescribed rivaroxaban had similar index LOS and PE-related outcomes, but fewer HACs, and lower total costs than those prescribed SOC.

Pulmonary Embolism: Contemporary Medical Management and Future Perspectives

Pulmonary embolism (PE) contributes substantially to the global disease burden. A key determinant of early adverse outcomes is the presence (and severity) of right ventricular dysfunction. Consequently, risk-adapted management strategies continue to evolve, tailoring acute treatment to the patients' clinical presentation, hemodynamic status, imaging and biochemical markers, and comorbidity. For subjects with hemodynamic instability or 'high-risk' PE, immediate systemic reperfusion treatment with intravenous thrombolysis is indicated; emerging approaches such as catheter-directed pharmacomechanical reperfusion might help to minimize the bleeding risk. Currently, direct, non-vitamin K-dependent oral anticoagulants are the mainstay of treatment for acute PE. They have been shown to simplify initial and extended anticoagulation regimens while reducing the bleeding risk compared to vitamin K antagonists. (This is a review article based on the invited lecture of the 37th Annual Meeting of Japanese Society of Phlebology.).

[Acute pulmonary embolism in the emergency department: What do the guidelines say?]

The therapeutic strategy of acute pulmonary embolism (PE) is based on risk stratification of early mortality in the emergency department. Anticoagulant therapy should be given to all PE patients as early as possible, and direct oral anticoagulants are expected to replace vitamin K antagonists in the majority of cases. The use of a reperfusion strategy should always be considered in patients with high-risk PE defined as PE with clinical hemodynamic instability. Surgical or percutaneous embolectomy is an alternative in case of contraindication to thrombolytic therapy in these patients. Intermediate-risk PEs defined by a sPESI score of≥1 warrant hospitalization, and continuous care monitoring for patients presenting with elevated biomarkers and right ventricular dysfunction. Low risk PEs (sPESI=0) could be managed on an outpatient basis, provided that a care pathway had been defined beforehand.

Early decision-making in acute pulmonary embolism: a retrospective clinical audit

BACKGROUND

There is increasing evidence supporting early discharge of patients with acute pulmonary embolism (aPE) deemed 'low prognostic risk' as a safe and viable alternative to admission if identified correctly by guideline algorithms.

AIM

To determine if risk stratification guidelines were followed accurately in an Australian tertiary hospital.

METHODS

Patients admitted to the emergency department with a diagnosis of PE were included from December 2012 to December 2017. The 272 patients were retrospectively assessed for prognostic risk prior to and after release of the 2014 European Society of Cardiology (ESC) guidelines. This included the simplified Pulmonary Embolism Severity Index (sPESI), and evidence of right heart dysfunction. Thereafter, patients were dichotomised into low (i.e. sPESI = 0) and non-low (i.e. sPESI ≥1 with or without the evidence of right heart dysfunction) prognostic risk groups.

RESULTS

Prior to ESC guideline release, 52 (65%) of the 80 patients diagnosed with PE were non-low risk and 12 (23%) of these were discharged home; 11 (91.7%) of the 12 discharges had unrecognised sPESI medical history components. After ESC guideline release, 122 (63.5%) of the 192 patients were non-low risk and 20 (16.4%) of these were discharged home; 18 (90%) of the 20 discharges had unrecognised sPESI medical history components.

CONCLUSION

We found that the sPESI score is not adequately applied in determining prognostic risk for acute PE. In cases of non-low-risk discharge, both prior to and after ESC guideline release, the medical history components of the sPESI score are under-recognised as a marker of increased prognostic risk.

Novel Anticoagulant Treatment for Pulmonary Embolism with Direct Oral Anticoagulants Phase 3 Trials and Clinical Practice

Anticoagulant therapy is the cornerstone of therapeutic management in acute venous thromboembolism (VTE), consisting of pulmonary embolism and deep vein thrombosis. Direct oral anticoagulants (DOACs) have become the standard of care because of their good safety profile and ease of use in clinical practice. Indeed, phase 3 randomized trials (AMPLIFY, EINSTEIN, RECOVER, and HOKUSAI studies) showed that DOACs provided a similar efficacy and a better safety than conventional treatment with parenteral heparin with overlapping loading dose of vitamin K antagonists in acute VTE therapeutic management. The results of published data from real-world registries confirm the safety and efficacy of DOACs demonstrated in the phase 3 trials.

Non-vitamin K antagonist oral anticoagulants for pulmonary embolism: who, where and for how long?

INTRODUCTION

Acute pulmonary embolism (PE) is a relatively common cardiopulmonary emergency that is a major cause of hospitalization and morbidity and is the primary cause of mortality associated with venous thromboembolism (VTE). During the last decade, one of the biggest changes in the management of PE has been the approval of four non-vitamin K antagonist oral anticoagulants (NOACs; apixaban, dabigatran, edoxaban and rivaroxaban) for the treatment of PE and deep vein thrombosis and secondary prevention of VTE. Areas covered: This article reviews the evolving management of PE in the NOAC era and addresses three fundamental questions: who should receive NOACs over conventional heparin/vitamin K antagonist regimens for the treatment of acute PE; should patients be treated as inpatients or outpatients; and how long should patients be treated to reduce the risk of recurrence? Expert commentary: The management of PE is changing. NOACs provide new anticoagulant treatment options for patients with PE, based on Phase III clinical study results. The consistent efficacy and safety profile of NOACs across many PE patient subgroups, including the elderly, fragile patients, those with active cancer and high-risk (right ventricular dysfunction) patients, suggests NOAC use will increase among these patients.

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.

Pathways for outpatient management of venous thromboembolism in a UK centre

It has become widely recognised that outpatient treatment may be suitable for many patients with venous thromboembolism. In addition, non-vitamin K antagonist oral anticoagulants that have been approved over the last few years have the potential to be an integral component of the outpatient care pathway, owing to their oral route of administration, lack of requirement for routine anticoagulation monitoring and simple dosing regimens.

A robust pathway for outpatient care is also vital; one such pathway has been developed at Sheffield Teaching Hospitals in the UK. This paper describes the pathway and the arguments in its favour as an example of best practice and value offered to patients with venous thromboembolism.

The pathway has two branches (one for deep vein thrombosis and one for pulmonary embolism), each with the same five-step process for outpatient treatment. Both begin from the point that the patient presents (in the Emergency Department, Thrombosis Clinic or general practitioner’s office), followed by diagnosis, risk stratification, treatment choice and, finally, follow-up.

The advantages of these pathways are that they offer clear, evidence-based guidance for the identification, diagnosis and treatment of patients who can safely be treated in the outpatient setting, and provide a detailed, stepwise process that can be easily adapted to suit the needs of other institutions. The approach is likely to result in both healthcare and economic benefits, including increased patient satisfaction and shorter hospital stays.

Characteristics and clinical value of 3D MR imaging in the diagnosis of pulmonary embolism

The aim of the present study was to investigate the characteristics and value of 3D dynamic contrast-enhanced magnetic resonance pulmonary angiography (3D-DCE-MRPA) for the diagnosis of pulmonary embolism (PE). Among patients suspected with PE, 30 cases were scheduled for 3D-DCE-MRPA [magnetic resonance imaging (MRI) group], and 30 cases were examined using multislice computed tomographic pulmonary angiography (msCTPA) [computed tomography (CT) group]. Direct signs including location, number, morphology of emboli, and indirect signs such as pulmonary infarction, pneumonia and pleural effusion, were analyzed. Pulmonary artery enhancement was observed. Image quality was contrasted, branches of the pulmonary artery revealed, and differences in sensitivity, specificity and signal-to-noise ratio (SNR) were compared. The number and morphology of emboli in the two groups were compared, and there were no significant differences (P>0.05). In the MRI group, significantly more emboli were located in segmental and subsegmental bronchi (P<0.05). The indirect signs in the two groups were compared and the differences were not statistically significant (P>0.05). The difference in image quality between the two groups was not statistically significant (P>0.05). Levels 5 and 6 of the pulmonary artery branch were more evident in the MRI group compared to the CT group. The SNR and carrier-to-noise ratio in the MRI group were significantly higher than those in the CT group (P<0.05). Twenty-six cases of PE were diagnosed in the CT group, with a sensitivity of 90.5% and specificity of 86.7%. Twenty-five cases were diagnosed in the MRI group, with a sensitivity of 92.3% and specificity of 84.2%. In conclusion, 3D-DCE-MRPA surpassed msCTPA in revealing segmental and subsegmental pulmonary artery PE.