Treatment of submassive pulmonary embolism with tenecteplase or placebo: cardiopulmonary outcomes at 3 months: multicenter double-blind, placebo-controlled randomized trial

Aggressive Treatment of Intermediate-Risk Patients with Acute Symptomatic Pulmonary Embolism

Contemporary studies of acute pulmonary embolism (PE) have evaluated the role of thrombolytics in intermediate-risk PE. Significant findings are that thrombolytic therapy may prevent hemodynamic deterioration and all-cause mortality but increases major bleeding. Benefits and harms are finely balanced with no convincing net benefit from thrombolytic therapy among unselected patients. Among patients with intermediate risk PE, additional prognostic factors or subtle hemodynamic changes might alter the risk-benefit assessment in favor of thrombolytic therapy before obvious hemodynamic instability.

Comparison of acute and convalescent biomarkers of inflammation in patients with acute pulmonary embolism treated with systemic fibrinolysis vs. placebo

: Previous studies have associated biomarkers indicative of acute inflammation with pulmonary embolism, which may amplify coagulation, inhibit fibrinolysis and increase risk of venous thromboembolism (VTE) recurrence. The aim of this study was to measure inflammatory and hemostatic biomarkers in acute submassive pulmonary embolism at diagnosis and 3-month follow-up and to test the impact of treatment with fibrinolysis. Secondary analysis of a multicenter, double-blinded, randomized controlled trial including patients with submassive pulmonary embolism. Blood samples were obtained within 24 h of diagnosis and prior to bolus-dose tenecteplase (TNK) or placebo; all patients received standard anticoagulation and blood was redrawn 3 months later. Plasma concentrations of inflammatory [Interleukin 6 (IL-6), C-reactive protein (CRP), myeloperoxidase (MPO)] and hemostatic [plasminogen activator inhibitor-1 (PAI-1), fibrinogen, thrombin-activatable fibrinolysis inhibitor and D-dimer] biomarkers were quantified. The median values of the biomarkers of inflammation (IL-6, CRP, MPO) were all significantly decreased at 3-month follow-up, ranging from a 60 to 91% reduction over this time period. Concentrations of PAI-1 and fibrinogen did not change significantly. D-dimer concentration at 3-month follow-up was lower in patients treated with fibrinolysis vs. placebo and appeared to have a trend toward significance (placebo 310 vs. TNK 220 ng/ml, P = 0.051). Acute pulmonary embolism causes marked but transient inflammation, as demonstrated by the significant elevation in the inflammatory biomarkers at diagnosis, followed by their reduction in more than 80% of patients at 3-month follow-up.

Predictors of failure and complications of catheter-directed interventions for pulmonary embolism

OBJECTIVE

Catheter-directed interventions (CDIs) are increasingly performed for acute pulmonary embolism (PE) as they are presumed to provide similar therapeutic benefits to systemic thrombolysis while decreasing the dose of thrombolytic required and the associated risks. This study aimed to identify factors associated with CDI failure and to describe anticipated complications.

METHODS

Consecutive patients who underwent CDI for massive or submassive PE between 2009 and 2015 were identified; outcomes and complications were retrospectively collected. CDI clinical failure was defined as major bleeding, perioperative stroke or other major adverse procedure-related event, decompensation for submassive or persistent shock for massive PE, need for surgical thromboembolectomy, or in-hospital death. Univariate analysis was used to study the factors associated with CDI failure.

RESULTS

There were 102 patients who received a CDI during the study period (36 standard catheter thrombolysis, 60 ultrasound assisted, 6 other; age, 59.2 ± 15.9 years; male, 50 [49.0%]; massive PE, 14 [13.7%]). Five patients (4.9%) had a major contraindication and 15 patients (14.7%) had a minor contraindication to systemic thrombolysis. The mean alteplase dose was 28.2 ± 18.8 mg (range, 0-123 mg; three patients had already received systemic lysis). CDI failure occurred in 15 patients (14.7%; 7 in massive PE, 8 in submassive PE). Of these patients, seven had major bleeding events, whereas eight patients decompensated. Ten (9.8%) patients had minor bleeding events (four access related). Factors associated with CDI failure and major bleeding included massive PE, age ≥70 years, and major contraindication to thrombolytics. Both failures and bleeding events were independent of lysis dose and CDI technique.

CONCLUSIONS

CDIs for acute PE are not risk-free procedures, and their use should be individualized on the basis of a risk-benefit ratio. Particularly for patients with major contraindications to systemic thrombolytics, CDIs should be used selectively. Lytic dose, within the low-volume range administered in CDI, and type of CDI seem to have no impact on adverse events.

Determinants of in-hospital clinical outcome in patients with sub-massive pulmonary embolism

Introduction

There is limited data regarding in hospital determinants of clinical deterioration and outcome in sub massive pulmonary embolism (PE). We aimed to evaluate these determinants by comparing biomarkers, CT pulmonary angiogram echocardiography, electrocardiography variables.

Methods

57 patients of sub massive PE diagnosed on CT pulmonary angiogram were included. All patients received UFH on admission and were divided into two groups based on their clinical course. Group 1 comprised of patients who remained stable, group 2 of patients who showed signs of clinical deterioration.

Results

There were 34(59.6%) patients in group 1 and 23(40.4%) patients in group 2. No significant difference in age, gender, BMI. 59.37% had sub massive PE, 5.26% had mortality and 40.4% had clinical deterioration. Intravenous UFH infusion given to 59.6%, systemic thrombolysis 22.8%, catheter directed mechanical breakdown 14%, surgical embolectomy in 3.5% patients. S1Q3T3, new onset RBBB, T wave inversion > 1.63 mm, Basal RV size > 40 mm, RV: LV ratio > 1.2, Global RV longitudinal strain <−10.75% and RVSP > 39 mmHg profiled high risk group. Serum BNP and CT pulmonary angiogram derived scores didn’t differ significantly although CT findings helped to exclude low risk patients (specificity 88%, sensitivity 95%).

Conclusions

Physicians should be aware that patients who have ECG and Echocardiography changes suggestive of right ventricular strain and dysfunction above the cut off values and have documented thrombus in Proximal branches (RPA/LPA) or in distal portion of main pulmonary artery may require aggressive management with systemic/catheter based thrombolysis besides routine anticoagulation with heparin to prevent clinical deterioration.

Patient Assessment: Clinical Presentation, Imaging Diagnosis, Risk Stratification, and the Role of Pulmonary Embolism Response Team

Pulmonary embolism (PE) is currently the third leading cause of death and moreover is likely underdiagnosed. PE remains the most common preventable cause of hospital deaths in the United States, which may be attributable to its diagnostic challenges. Although difficult to diagnose, patient mortality rates are time-dependent, and thus, the suspicion and diagnosis of PE in a timely manner is imperative. Diagnosis based on several criteria which may dictate imaging workup as well as laboratory tests and clinical parameters are discussed. The evolution of treatment guidelines via various clinical trials and recommendations is outlined, setting the stage for the use of fibrinolytics, whether systemic or catheter directed. Treatment, including fibrinolytics, is predicated on patient triage into three large categories-massive, submassive, or low-risk PE. Additionally, a relatively new concept of a multidisciplinary team composed of several subspecialty experts known as the PE response team (PERT) is discussed. PERT's timely and unified recommendations have been shown to optimize care and decrease mortality while tailoring treatment to each individual afflicted by PE.

Intervention in Massive Pulmonary Embolus: Catheter Thrombectomy/Thromboaspiration versus Systemic Lysis versus Surgical Thrombectomy

Massive pulmonary embolus (PE), defined as hemodynamic shock from acute PE, is a life-threatening condition. Deaths from massive PE, especially when unsuspected, occur within minutes to hours of onset and as such prompt intervention can be lifesaving. Acute massive PE patients have traditionally been candidates for treatment with intravenous systemic thrombolysis to improve pulmonary artery pressure, arteriovenous oxygenation, and pulmonary perfusion in an effort to reduce mortality. However, patients with contraindications to systemic thrombolysis or those who have failed thrombolysis may benefit from other techniques including endovascular and surgical embolectomy. This article will review the current medical management as well as catheter-directed therapies and surgical embolectomy in the treatment of patients with massive PE.

Efficacy and safety outcomes of recanalisation procedures in patients with acute symptomatic pulmonary embolism: systematic review and network meta-analysis

BACKGROUND

We aimed to review the efficacy and safety of recanalisation procedures for the treatment of PE.

METHODS

We searched PubMed, the Cochrane Library, EMBASE, EBSCO, Web of Science and CINAHL databases from inception through 31 July 2015 and included randomised clinical trials that compared the effect of a recanalisation procedure versus each other or anticoagulant therapy in patients diagnosed with PE. We used network meta-analysis and multivariate random-effects meta-regression to estimate pooled differences between each intervention and meta-regression to assess the association between trial characteristics and the reported effects of recanalisation procedures versus anticoagulation.

RESULTS

For all-cause mortality, there were no significant differences in event rates between any of the recanalisation procedures and anticoagulant treatment (full-dose thrombolysis: OR 0.60; 95% CI0.36 to 1.01; low-dose thrombolysis: 0.47; 95% CI 0.14 to 1.59; and catheter-associated thrombolysis: 0.31; 95% CI 0.01 to 7.96). Full-dose thrombolysis increased the risk of major bleeding (2.00; 95% CI 1.06 to 3.78) compared with anticoagulation. Catheter-directed thrombolysis was associated with the lowest probability of dying (surface under the cumulative ranking curve (SUCRA), 0.67), followed by low-dose thrombolysis (SUCRA, 0.66) and full-dose thrombolysis (SUCRA, 0.55). Similarly, low-dose thrombolysis was associated with the lowest probability of major bleeding (SUCRA, 0.61), followed by catheter-directed thrombolysis (SUCRA, 0.54) and full-dose thrombolysis (SUCRA, 0.17). The results were similar in sensitivity analyses based on restricting only to studies in haemodynamically stable patients with PE.

CONCLUSIONS

In the treatment of PE, recanalisation procedures do not seem to offer a clear advantage compared with standard anticoagulation. Low-dose thrombolysis was associated with the lowest probability of dying and bleeding.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42015024670.

Systemic Thrombolytic Therapy for Massive and Submassive Pulmonary Embolism

OBJECTIVE

To critically evaluate the published literature assessing the safety and efficacy of thrombolytic therapy for massive and submassive pulmonary embolism (PE).

METHODS

A search of human trials in the English-language (September 2017) was conducted through the MEDLINE database using the following terms: PE, tissue plasminogen activator, tenecteplase, and alteplase. 67 unique articles were identified, of which 24 clinical trials discussing clinical outcomes related to administration of either intravenous tenecteplase or alteplase were included.

RESULTS

Thrombolytic therapy with anticoagulation significantly reduced mortality compared to anticoagulation alone in massive PE. In submassive PE, thrombolytics reduced the rate of right ventricular dysfunction and hemodynamic collapse; however, there is an increased risk of major and minor bleeding with no benefit on long-term functional outcomes.

CONCLUSIONS

Patients with massive PE should receive thrombolytics when no major contraindications to therapy exist. Patients with submassive PE at highest risk for progression to hemodynamic instability should receive anticoagulation and be monitored for clinical deterioration. If an imminent risk of hemodynamic instability or cardiac arrest occurs, thrombolytics should be administered if no contraindications exist. Net mortality benefit and risk of bleeding must be considered when deciding to administer thrombolytic therapy in massive or submassive PE.

Catheter-Directed Thrombolysis for Pulmonary Embolism: The State of Practice

Acute pulmonary embolism (PE) is a major public health problem. It is the third most common cause of death in hospitalized patients. In the United States, there are up to 600,000 cases diagnosed per year with 100,000-180,000 acute PE-related deaths. Common risk factors include underlying genetic conditions, acquired conditions, and acquired hypercoagulable states. Acute PE increases the pulmonary vascular resistance and the load on the right ventricle (RV). Increased RV loading causes compensatory RV dilation, impaired contractility, tachycardia, and sympathetic activation. RV dilation and increased intramural pressure decrease diastolic coronary blood flow, leading to RV ischemia and myocardial necrosis. Ultimately, insufficient cardiac output from the RV causes left ventricular under-filling which results in systemic hypotension and cardiovascular collapse. Current prognostic stratification strategy separates acute PE into massive, submassive, and low-risk by presence or absence of sustained hypotension, RV dysfunction, and myocardial necrosis. Massive, submassive, and low-risk acute PE have mortality rates of 25%-65%, 3%, and <1%, respectively. Current PE management includes the use of anticoagulation alone, systemic thrombolysis, catheter-directed thrombolysis, and surgical embolectomy. This article will describe the current state of practice for catheter-directed thrombolysis and its role in the management of acute PE.

Cardiopulmonary Exercise Testing in Patients Following Massive and Submassive Pulmonary Embolism

Background

Little data exist regarding the functional capacity of patients following acute pulmonary embolism. We sought to characterize the natural history of symptom burden, right ventricular (RV) structure and function, and exercise capacity among survivors of massive and submassive pulmonary embolism.

Methods and Results

Survivors of submassive or massive pulmonary embolism (n=20, age 57±13.3 years, 8/20 female) underwent clinical evaluation, transthoracic echocardiography, and cardiopulmonary exercise testing at 1 and 6 months following hospital discharge. At 1 month, 9/20 (45%) patients had New York Heart Association II or greater symptoms, 13/20 (65%) demonstrated either persistent RV dilation or systolic dysfunction, and 14/20 (70%) had objective exercise impairment as defined by a peak oxygen consumption (V˙O₂) of <80% of age‐sex predicted maximal values (16.25 [13.4–20.98] mL/kg per minute). At 6 months, no appreciable improvements in symptom severity, RV structure or function, and peak V˙O₂ (17.45 [14.08–22.48] mL/kg per minute, P=NS) were observed. No patients demonstrated an exercise limitation attributable to either RV/pulmonary vascular coupling, as defined by a VE/VCO₂ slope >33, or a pulmonary mechanical limit to exercise at either time point. Similarly, persistent RV dilation or dysfunction was not significantly related to symptom burden or peak V˙O₂ at either time point.

Conclusions

Persistent symptoms, abnormalities of RV structure and function, and objective exercise limitation are common among survivors of massive and submassive pulmonary embolism. Functional impairment appears to be attributable to general deconditioning rather than intrinsic cardiopulmonary limitation, suggesting an important role for prescribed exercise rehabilitation as a means toward improved patient outcomes and quality of life.

Understanding haemorrhagic risk following thrombolytic therapy in patients with intermediate-risk and high-risk pulmonary embolism: a hypothesis paper

While systemic intravenous thrombolysis decreases mortality in patients with high-risk pulmonary embolism (PE), it clearly increases haemorrhagic risk. There are many contraindications to thrombolysis, and efforts should aim at selecting those patients who will benefit most, without suffering complications. The current review summarises the evidence for the use of thrombolytic therapy in PE. It clarifies the pathophysiological mechanisms in PE and acute cor pulmonale that increase the risk of bleeding following thrombolysis. It discusses future management challenges, namely tailored drug administration, new treatment monitoring techniques and catheter-directed thrombolysis.

How Fragile Are Clinical Trial Outcomes That Support the CHEST Clinical Practice Guidelines for VTE?

BACKGROUND

VTE remains a health concern for global populations. Clinical practice guidelines are necessary to guide physicians in the prophylaxis and treatment of VTE.

METHODS

Our investigation assessed the robustness of the underlying evidence in 21 randomized controlled trials (RCTs) used to support treatment recommendations in the 2016 update of the CHEST Guideline and Expert Panel Report on Antithrombotic Therapy for VTE Disease. We calculated the fragility index and fragility quotient for qualifying outcomes within RCTs.

RESULTS

The median fragility index for all studies was 5 (interquartile range, 1-9), with a median fragility quotient of 0.012 (interquartile range, 0.002-0.032).

CONCLUSIONS

Our conclusions parallel those of previous investigations of the fragility of RCT outcomes; we found that some outcomes used to support recommendations in AT10 are fragile. We recommend that the fragility index and fragility quotient be adopted as measures of robustness of clinical trial outcomes.

Design and rationale of a randomized trial comparing standard versus ultrasound-assisted thrombolysis for submassive pulmonary embolism

BACKGROUND

Catheter-directed interventions for the treatment of patients with submassive pulmonary embolism (sPE) have shown promise in rapidly improving right-sided heart strain and preventing decompensation to massive pulmonary embolism. Among various catheter interventions, ultrasound-assisted thrombolysis (USAT) has attracted interest as potentially having more efficient lytic effect that could achieve thrombolysis faster and with a reduced lytic dose. However, based on clinical evidence, it is unclear whether USAT is superior to standard catheter-directed thrombolysis (SCDT). We herein describe the study design of the Standard vs UltrasouNd-assiSted CathEter Thrombolysis for Submassive Pulmonary Embolism (SUNSET sPE) trial, an ongoing randomized clinical trial designed to address this question.

METHODS

Adults with sPE presenting or referred to our institution are considered for enrollment in the trial. At the discretion of the treatment team, all patients undergo a catheter-directed intervention plus concomitant therapeutic anticoagulation. Participants are randomized 1:1 to a USAT catheter or an SCDT catheter. Study assessors are blinded to treatment group. The primary outcome is clearance of pulmonary thrombus burden, assessed by postprocedure computed tomography angiography. Secondary outcomes include resolution of right ventricular strain by echocardiography; improvement in pulmonary artery pressures; and 3- and 12-month improvement in echocardiographic, functional capacity, and quality of life measures. The study is powered to detect a 50% improvement in pulmonary artery thrombus clearance. Our enrollment target is 40 patients per treatment arm.

CONCLUSIONS

SUNSET sPE is an ongoing randomized, head-to-head, single-blinded clinical trial with the goal of assessing whether USAT results in superior thrombus clearance compared with SCDT in patients with sPE. We expect the results of our study to inform future guidelines on choice of thrombolysis modality in this population of challenging patients.

From Acute to Chronic Thromboembolic Disease

After achievement of adequate anticoagulation, the natural history of acute pulmonary emboli ranges from near total resolution of vascular perfusion to long-term persistence of hemodynamically consequential residual perfusion defects. The persistence of perfusion defects is necessary, but not sufficient, for the development of chronic thromboembolic pulmonary hypertension (CTEPH). Approximately 30% of patients have persistent defects after 6 months of anticoagulation, but only 10% of those with persistent defects subsequently develop CTEPH. A number of clinical risk factors including increasing age, delay in anticoagulation from symptom onset, and the size of the initial thrombus have been associated with the persistence of perfusion defects. Likewise, a number of cellular and molecular pathways have been implicated in the failure of thrombus resolution, including impaired fibrinolysis, altered fibrinogen structure and function, increased local or systemic inflammation, and remodeling of the embolic material by neovascularization. Treatment with fibrinolytic agents at the time of initial presentation has not clearly improved the frequency or degree of recovery of pulmonary vascular perfusion. A better understanding of the interplay between clinical risk factors and pathogenic mechanisms may enhance the ability to prevent and treat CTEPH in the future.

Perioperative pulmonary thromboembolism: current concepts and treatment options

PURPOSE OF REVIEW

Anesthesiologists are familiar with pulmonary emboli prophylaxis paradigms and many have witnessed acute intraoperative embolization. Clinicians must balance conservative anticoagulation and aggressive intervention in perioperative submassive pulmonary emboli, yet the bulk of the literature excludes surgery as a relative contraindication. This review will summarize the current treatment options for acute pulmonary emboli, drawing attention to special considerations in perioperative submassive pulmonary emboli, and discuss right ventricular monitoring to improve assessment of intervention efficacy.

RECENT FINDINGS

Recent reviews have identified the elevated risk and inadequacy of treatment of pulmonary embolism in intra and postoperative patients, in part because of the risks of systemic anticoagulation. Early studies of catheter-directed therapies have shown promising efficacy with a reduction in bleeding risk, which is especially important for perioperative patients. Success relies on defining endpoints, yet the practice of measuring mean pulmonary artery pressure alone to assess intervention efficacy is flawed.

SUMMARY

Identifying submassive pulmonary emboli that requires treatment and optimizing therapy remains difficult. Researchers must consider avoiding systemic anticoagulation and focus on designing trials that evaluate intervention efficacy in surgical patients. The success of catheter-directed therapy in early trials warrants further investigation into using these therapies in the treatment of perioperative submassive pulmonary emboli.

Rationale for catheter directed therapy in pulmonary embolism

Pulmonary embolism (PE) is a widespread health concern associated with major morbidity and mortality. Catheter directed therapy (CDT) has emerged as a treatment option for acute PE adding to the current potential options of systemic thrombolysis or anticoagulation. The purpose of this review is to understand the rationale and indications for CDT in patients with PE. While numerous studies have shown the benefits of systemic thrombolysis compared to standard anticoagulation, these are balanced by the increased risk of major bleeding. With this in mind, CDT has the potential to offer the benefits of systemic thrombolysis and in theory, a reduced risk of bleeding. This article will review current treatment guidelines in both massive and submassive PE evaluating both short and long term benefits. The role of CDT will be highlighted, with an emphasis on efficacy and safety.

Systemic Thrombolysis, Catheter-Directed Thrombolysis, and Anticoagulation for Intermediate-risk Pulmonary Embolism: A Simulation Modeling Analysis

OBJECTIVES

Decision making around the use of thrombolysis for patients with intermediate-risk (submassive) pulmonary embolism (PE) remains challenging. Studies indicate favorable clinical outcomes with systemic thrombolytics (intravenous tissue plasminogen activator [IV tPA]), but the risk of major bleeding and hemorrhagic stroke is a deterrent. Catheter-directed thrombolysis (CDT) may be a preferable strategy, as it has been shown to have a lower risk of bleeding than systemic thrombolysis. However, a three-arm randomized control study comparing IV tPA, CDT, and anticoagulation alone, with long-term follow up, would be costly and is unlikely to be performed. The aim of this study was to use decision modeling to quantitatively estimate the differences between the three strategies.

METHODS

We created an individual-level state-transition model to simulate long-term outcomes of a hypothetical patient cohort treated with IV tPA, CDT, or anticoagulation alone. Our model incorporated clinical randomized controlled trial and longitudinal study data to inform patient characteristics and outcomes specific to each study arm. The base case was a 65-year-old patient. Additionally, we utilized preliminary data published by the Pulmonary Embolism Response Team at the Massachusetts General Hospital. Variance in model inputs was addressed with deterministic and probabilistic sensitivity analyses. Our primary endpoint was quality-adjusted life-years (QALYs). Secondary endpoints included total cost and incremental cost-effectiveness ratios (ICERs).

RESULTS

Catheter-directed thrombolysis (mean, 95% confidence interval [CI] = 7.388 [7.381-7.396] QALYs) resulted in the most long-term utility for eligible patients compared to anticoagulation alone (7.352 [7.345-7.360] QALYs) or IV tPA (7.343 [7.336-7.351] QALYs). Patients receiving CDT had an elevated risk of hemorrhagic stroke in comparison to anticoagulation alone; however, patients treated with anticoagulation alone were more likely to experience recurrent PE associated adverse outcomes. Results were stable with sensitivity analyses varying age and sex. Our probabilistic sensitivity analysis assessing joint variance predicts CDT to be the most effective strategy, when measured by mean QALYs, in 98.4% of runs, while systemic thrombolysis was favored over anticoagulation alone 34.4% of the time. The ICER of CDT compared to anticoagulation was $317,042 per QALY gained.

CONCLUSION

In our model, for those eligible, CDT results in the largest number of QALYs for patients with intermediate-risk PE, although it is relatively expensive and the absolute difference in QALYs between anticoagulation alone and CDT is small. Future studies that provide data on longitudinal quality-of-life outcomes of patients treated for PE and characteristics of CDT would be beneficial to augment model inputs, inform assumptions, and validate results.

Physician failure to stratify patients hospitalized with acute pulmonary embolism

OBJECTIVES

In 2011, the AHA recommended risk stratification of patients with acute pulmonary embolism (PE). Failure to risk stratify may cause under recognition of intermediate-risk PE and its attendant short- and long-term consequences. We sought to determine if patients hospitalized with acute PE were appropriately risk stratified according to the 2011 AHA Scientific Statement within our hospital system and whether differences exist in adherence to risk stratification by hospital or treating hospital service. We also wished to know the frequency of in-hospital consultations for acute PE which might assist in the risk stratification process.

METHODS

This is a retrospective chart audit of all patients hospitalized with a diagnosis of acute PE between January 2011 and December 2013 at our 937-bed metropolitan, three hospital system comprised of academic University, neuroscience Specialty, and teaching Community hospitals. We evaluated the presence of imaging, laboratory tests, and specialty consultation within 72 h of PE diagnosis by hospital.

RESULTS

701 patients with acute PE were admitted to our hospital system during the study period. 308 patients (43.9%) met criteria for intermediate-risk PE. 347 patients (49.5%) were considered 'Low-Risk - At Risk', patients defined in a low-risk category not having undergone all recommended risk stratification testing and so truly may have been in a higher risk category. No specialty consultations were utilized for 265 patients (37.8%).

CONCLUSIONS

Our large metropolitan hospital system inadequately risk stratifies hospitalized patients with acute PE. Because nearly one-half of patients with acute PE did not have all recommended testing, clinicians may be under recognizing patients with intermediate-risk PE and their risk for long-term morbidity. Specialty consultations were underutilized and may help guide medical decision-making.

Late consequences of venous thromboembolism: Measuring quality of life after deep vein thrombosis and pulmonary embolism

The identification of specific post-thrombotic complications as well as an increased appreciation of the importance of patient-reported outcome measures have triggered an interest in studying health-related quality of life (HRQoL) in patients with a history of venous thromboembolism (VTE). In order to enable a comprehensive assessment of HRQoL in clinical trials it is recommended that both generic and disease-specific questionnaires be used. SF-36 and EQ-5D are the most widely used generic questionnaires in VTE studies, whereas several disease-specific questionnaires have been developed to evaluate HRQoL following deep vein thrombosis (DVT) and in chronic venous disease (CVD). The most widely used of these is the VEINES-QOL/Sym, which was developed for CVD. VT-QOL and DVTQOL are both questionnaires developed to evaluate HRQoL after DVT, while PEmb-QoL is currently the only available disease-specific questionnaire developed specifically for pulmonary embolism (PE). Although studies show inconsistent results, patients who sustain DVT seem in general to report similar HRQoL compared to the general population. However, patients who develop PTS after DVT report poorer HRQoL using both generic and disease-specific questionnaires. HRQoL appears to be impaired in patients who sustain PE compared to the general population. In these patients, persistent dyspnea after PE has been shown to be a predictor of reduced HRQoL. Further work is needed to develop practical, patient-derived, valid, reliable and responsive disease-specific HRQoL instruments covering the specific aspects of these diseases.

Impact of Thrombolytic Therapy on the Long-Term Outcome of Intermediate-Risk Pulmonary Embolism

BACKGROUND

The long-term effect of thrombolytic treatment of pulmonary embolism (PE) is unknown.

OBJECTIVES

This study investigated the long-term prognosis of patients with intermediate-risk PE and the effect of thrombolytic treatment on the persistence of symptoms or the development of late complications.

METHODS

The PEITHO (Pulmonary Embolism Thrombolysis) trial was a randomized (1:1) comparison of thrombolysis with tenecteplase versus placebo in normotensive patients with acute PE, right ventricular (RV) dysfunction on imaging, and a positive cardiac troponin test result. Both treatment arms received standard anticoagulation. Long-term follow-up was included in the third protocol amendment; 28 sites randomizing 709 of the 1,006 patients participated.

RESULTS

Long-term (median 37.8 months) survival was assessed in 353 of 359 (98.3%) patients in the thrombolysis arm and in 343 of 350 (98.0%) in the placebo arm. Overall mortality rates were 20.3% and 18.0%, respectively (p = 0.43). Between day 30 and long-term follow-up, 65 deaths occurred in the thrombolysis arm and 53 occurred in the placebo arm. At follow-up examination of survivors, persistent dyspnea (mostly mild) or functional limitation was reported by 36.0% versus 30.1% of the patients (p = 0.23). Echocardiography (performed in 144 and 146 patients randomized to thrombolysis and placebo, respectively) did not reveal significant differences in residual pulmonary hypertension or RV dysfunction. Chronic thromboembolic pulmonary hypertension (CTEPH) was confirmed in 4 (2.1%) versus 6 (3.2%) cases (p = 0.79).

CONCLUSIONS

Approximately 33% of patients report some degree of persistent functional limitation after intermediate-risk PE, but CTEPH is infrequent. Thrombolytic treatment did not affect long-term mortality rates, and it did not appear to reduce residual dyspnea or RV dysfunction in these patients. (Pulmonary Embolism Thrombolysis study [PEITHO]; NCT00639743).

Systemic Thrombolysis for Pulmonary Embolism: Who and How

Anticoagulation has been shown to improve mortality in acute pulmonary embolism (PE). Initiation of anticoagulation should be considered when PE is strongly suspected and the bleeding risk is perceived to be low, even if acute PE has not yet been proven. Low-risk patients with acute PE are simply continued on anticoagulation. Severely ill patients with high-risk (massive) PE require aggressive therapy, and if the bleeding risk is acceptable, systemic thrombolysis should be considered. However, despite clear evidence that parenteral thrombolytic therapy leads to more rapid clot resolution than anticoagulation alone, the risk of major bleeding including intracranial bleeding is significantly higher when systemic thrombolytic therapy is administered. It has been demonstrated that right ventricular dysfunction, as well as abnormal biomarkers (troponin and brain natriuretic peptide) are associated with increased mortality in acute PE. In spite of this, intermediate-risk (submassive) PE comprises a fairly broad clinical spectrum. For several decades, clinicians and clinical trialists have worked toward a more aggressive, yet safe solution for patients with intermediate-risk PE. Standard-dose thrombolysis, low-dose systemic thrombolysis, and catheter-based therapy which includes a number of devices and techniques, with or without low-dose thrombolytic therapy, have offered potential solutions and this area has continued to evolve. On the basis of heterogeneity within the category of intermediate-risk as well as within the high-risk group of patients, we will focus on the use of systemic thrombolysis in carefully selected high- and intermediate-risk patients. In certain circumstances when the need for aggressive therapy is urgent and the bleeding risk is acceptable, this is an appropriate approach, and often the best one.

Pulmonary Embolism in 2017: How We Got Here and Where Are We Going?

In the 1970s, both the Urokinase Pulmonary Embolism and Urokinase-Streptokinase Pulmonary Embolism trials began the quest to develop thrombolytic therapy for the treatment of acute massive and submassive pulmonary embolism (PE). The goals of these studies were the immediate reduction in clot burden, restoration of hemodynamic stability, and improved survival. Major bleeding became the major barrier for clinicians to employ these therapies. From 1980s to the present time, a number of studies using recombinant tissue-type plasminogen activator for achieving these same above outcomes were completed but major bleeding continued to remain an adoption barrier. Finally, the concept of bringing the thrombolytic agent into the clot has entered the quest for the Holy Grail in the treatment of PE. This article will review all the major trials using peripheral thrombolysis and provide insight into the need for a team approach to pulmonary care (Pulmonary Embolism Response Team), standardization of pulmonary classification, and the need for trials designed for both short- and long-term outcomes using thrombolysis for selected PE populations.

A Pulmonary Embolism Response Team: initial experiences and future directions

INTRODUCTION

Acute pulmonary embolism (PE) is a common cardiovascular condition resulting in significant morbidity and mortality. Consensus recommendations suggest risk stratification of patients into three main categories: high-risk or 'massive' PE, intermediate-risk or 'submassive' PE, and low-risk PE. Given the relative dearth of prospective, randomized clinical trials delineating optimal selection of the diverse medical, interventional, and surgical treatment approaches, clinical care requires a multidisciplinary expert approach to patients with PE. Areas covered: The Massachusetts General Hospital (MGH) Pulmonary Embolism Response Team (PERT) was the first of its kind to create a multidisciplinary, rapid response team for acute PE, integrated within a research and educational framework. The MGH PERT has treated more than 700 patients with PE, the majority of which are in the 'massive' or 'submassive' categories. The PERT Consortium™ was founded in 2015 as a collaborative network between the growing number of PERT programs internationally, with greater than 80 institutions participating within one year of establishment. Expert commentary: Since its advent, the PERT model has expanded throughout the United States and internationally through a collaborative institutional and research network. PERT may represent a new standard for the care of patients with acute PE.

Pulmonary Embolism: The Astute Interventional Radiology Clinician

There has been a resurgence of interest in defining the optimal treatment for severe pulmonary embolism (PE), fueled by pivotal and provocative trials, new catheter-based medical devices, and growing evidence of deleterious short- and long-term outcomes. In this environment, and especially given the multidisciplinary nature of PE care, the interventional radiologist (IR) needs to become an astute, disease-specific expert. This review article describes the following "steps" an IR can take to reach this level: (1) understand PE stratification and epidemiology; (2) recognize the treatment goals for massive PE; (3) recognize the wide range of attitudes toward therapeutic escalation for submassive PE; (4) recognize what we do not know about the treatment of submassive PE and the limitations of current studies; (5) know the literature surrounding inferior vena cava filter insertion for severe PE; (6) integrate into the longitudinal care of the patient; and (7) be at the leading edge of new trials and technologies.

Safety of catheter-directed thrombolysis for massive and submassive pulmonary embolism: Results of a multicenter registry and meta-analysis

OBJECTIVES

To evaluate the safety and efficacy of catheter-directed thrombolysis (CDT) in the treatment of acute pulmonary embolism (PE).

BACKGROUND

The use of CDT for the treatment of acute submassive and massive PE is increasing in frequency. However, its safety and efficacy have not been well elucidated.

METHODS

This study is made of two parts: one is a two-center registry of acute PE patients treated with CDT. The safety outcome evaluated was any major complication including fatal, intracranial (ICH), intraocular, or retroperitoneal hemorrhage or any overt bleeding requiring transfusion or surgical repair. The efficacy outcome was acute change in invasive pulmonary artery systolic pressure (PASP). The second part is a meta-analysis of all contemporary studies that used CDT for PE. Reported outcomes are the same as in the registry, with the addition of right ventricular to left ventricular (RV/LV) ratio change.

RESULTS

In the registry, 137 patients were included (age 59 ± 15, 50% male, 88% submassive PE). ICH occurred in two patients and major complications in 13 (9.4%). PASP decreased post procedure by 19 ± 15 mm Hg (95% CI 16-23). In the meta-analysis, 16 studies were included with 860 patients. Rate of ICH was 0.35% and the major complication rate was 4.65%, most requiring transfusion only. In-hospital mortality was 12.9% in the massive and 0.74% in the submassive group. All studies showed improvement in PASP and/or RV/LV ratio post CDT.

CONCLUSIONS

CDT is associated with a low major complication rate. Randomized studies are needed to evaluate its efficacy relative to anticoagulation alone. © 2017 Wiley Periodicals, Inc.

Echocardiography in the Evaluation of Pulmonary Embolism

Pulmonary embolism is a major cause of mortality. Acute pulmonary embolism also encompasses a wide clinical spectrum of severity, ranging from asymptomatic silent disease to hemodynamic instability and shock. Echocardiography is a useful modality to improve treatment strategies for pulmonary embolus. Echocardiography plays a role in risk stratification at the time of diagnosis. The evaluation of the right ventricle (RV) has evolved over time. RV variables evaluated by echocardiography include RV size, RV/left ventricular ratio, RV fractional area of change, tricuspid annular plane systolic excursion, RV systolic pressure, and RV Tei index. It has also been used in determining treatment strategies and following the success of treatment. Multiple echocardiographic criteria have been studied to improve risk stratification and outcomes from pulmonary embolism. Further studies are needed to assess the appropriate quantitative echocardiographic parameters.

The 2016 American College of Chest Physicians treatment guidelines for venous thromboembolism: a review and critical appraisal

The American College of Chest Physicians recently updated their practice guidelines for the treatment of patients with venous thromboembolism, comprising deep vein thrombosis and pulmonary embolism. The 2016 guidelines represent the tenth iteration of these guidelines, which are widely used, and are considered as the reference standard for practice guidelines related to venous thromboembolism. The objectives of this review are to highlight the key recommendations that are new in these guidelines, to address recommendations that may be considered controversial, and to touch on areas of ongoing research that may better inform some of these recommendations.

The Use of Thrombolysis for Acute Pulmonary Embolism in the United States: National Trends and Patient Characteristics from 2006 to 2011

BACKGROUND

Thrombolysis for the treatment of pulmonary embolism (PE) has received significant attention in the literature over the past 10 years.

OBJECTIVE

Our primary objective was to examine the trend in thrombolysis use in the United States from 2006 to 2011. Secondary objectives include examining patient and hospital characteristics associated with receiving thrombolysis and rates of complications associated with thrombolysis.

METHODS

In this retrospective cohort study, we used the Nationwide Inpatient Sample from 2006 to 2011 to identify patients with a diagnosis of PE who received or did not receive thrombolytic agents.

RESULTS

Examining the records of 47,911,414 hospital discharges identified a cohort of 1,317,329 patients with PE; of these patients, 10,617 received thrombolysis. During the study period, there was a 30% relative increase in the use of thrombolysis, from 0.68% (95% confidence interval [CI] 0.64-0.73%) to 0.89% (95% CI 0.83-0.95%; p < 0.01). After controlling for all factors in the model, factors associated with decreased access to thrombolysis were increasing age (odds ratio [OR] 0.981 [95% CI 0.980-0.982]; p < 0.01), female sex (OR 0.78 [95% CI 0.75-0.81]; p < 0.01), Black race (OR 0.86 [95% CI 0.81-0.91]; p < 0.01), Hispanic race (OR 0.78 [95% CI 0.71-0.86]; p < 0.01), other race (OR 0.72 [95% CI 0.59-0.88]; p = 0.02), and rural hospital location (OR 0.48 [95% CI 0.43-0.52]; p < 0.01).

CONCLUSIONS

The use of thrombolysis increased between 2006 and 2011 in the United States. Patients who receive thrombolysis tend to be white men, live in higher-income ZIP codes, and receive the therapy at large academic teaching hospitals.

Persistent right ventricular dysfunction, functional capacity limitation, exercise intolerance, and quality of life impairment following pulmonary embolism: Systematic review with meta-analysis

Long-term right ventricular (RV) function, functional capacity, exercise capacity, and quality of life following pulmonary embolism (PE), and the impact of thrombolysis, are unclear. A systematic review of studies that evaluated these outcomes with ⩾ 3-month mean follow-up after PE diagnosis was performed. For each outcome, random effects meta-analyses were performed. Twenty-six studies (3671 patients) with 18-month median follow-up were included. The pooled prevalence of RV dysfunction was 18.1%. Patients treated with thrombolysis had a lower, but not statistically significant, risk of RV dysfunction versus those treated with anticoagulation (odds ratio: 0.51, 95% CI: 0.24 to 1.13, p=0.10). Pooled prevalence of at least mild functional impairment (NYHA II–IV) was 33.2%, and at least moderate functional impairment (NYHA III–IV) was 11.3%. Patients treated with thrombolysis had a lower, but not statistically significant, risk of at least moderate functional impairment versus those treated with anticoagulation (odds ratio: 0.48, 95% CI: 0.15 to 1.49, p=0.20). Pooled 6-minute walk distance was 415 m (95% CI: 372 to 458 m), SF-36 Physical Component Score was 44.8 (95% CI: 43 to 46), and Pulmonary Embolism Quality of Life (QoL) Questionnaire total score was 9.1. Main limitations included heterogeneity among studies for many outcomes, variation in the completeness of data reported, and inclusion of data from non-randomized, non-controlled, and retrospective studies. Persistent RV dysfunction, impaired functional status, diminished exercise capacity, and reduced QoL are common in PE survivors. The effect of thrombolysis on RV function and functional status remains unclear.

Management of venous thromboembolism: an update

Venous thromboembolism (VTE), which constitutes pulmonary embolism and deep vein thrombosis, is a common disorder associated with significant morbidity and mortality. Landmark trials have shown that direct oral anticoagulants (DOACs) are as effective as conventional anticoagulation with vitamin K antagonists (VKA) in prevention of VTE recurrence and associated with less bleeding. This has paved the way for the recently published guidelines to change their recommendations in favor of DOACs in acute and long-term treatment of VTE in patients without cancer. The recommended treatment of VTE in cancer patients remains low-molecular-weight heparin. The initial management of pulmonary embolism (PE) should be directed based on established risk stratification scores. Thrombolysis is an available option for patients with hemodynamically significant PE. Recent data suggests that low-risk patients with acute PE can safely be treated as outpatients if home circumstances are adequate. There is lack of support for use of inferior vena cava filters in patients on anticoagulation. This review describes the acute, long-term, and extended treatment of VTE and recent evidence on the management of sub-segmental PE.

Pulmonary embolism: the diagnosis, risk-stratification, treatment and disposition of emergency department patients

The diagnosis or exclusion of pulmonary embolism (PE) remains challenging for emergency physicians. Symptoms can be vague or non-existent, and the clinical presentation shares features with many other common diagnoses. Diagnostic testing is complicated, as biomarkers, like the D-dimer, are frequently false positive, and imaging, like computed tomography pulmonary angiography, carries risks of radiation and contrast dye exposure. It is therefore incumbent on emergency physicians to be both vigilant and thoughtful about this diagnosis. In recent years, several advances in treatment have also emerged. Novel, direct-acting oral anticoagulants make the outpatient treatment of low risk PE easier than before. However, the spectrum of PE severity varies widely, so emergency physicians must be able to risk-stratify patients to ensure the appropriate disposition. Finally, PE response teams have been developed to facilitate rapid access to advanced therapies (e.g., catheter directed thrombolysis) for patients with high-risk PE. This review will discuss the clinical challenges of PE diagnosis, risk stratification and treatment that emergency physicians face every day.

Major publications in the critical care pharmacotherapy literature: January-December 2014

PURPOSE

Nine recently published articles and one guideline with important implications for critical care pharmacy practice are summarized.

SUMMARY

The Critical Care Pharmacotherapy Literature Update (CCPLU) group includes more than 40 experienced critical care pharmacists across the United States. Group members monitor 29 peer-reviewed journals on an ongoing basis to identify literature relevant to pharmacy practice in the critical care setting. After evaluation by CCPLU group members, selected articles are chosen for summarization and distribution to group members nationwide based on applicability to practice, relevance, and study design and strength. Hundreds of relevant articles were evaluated by the group in 2014, of which 114 were summarized and disseminated to CCPLU group members. From among those 114 publications, 10 deemed to be of particularly high utility to the critical care practitioner were selected for inclusion in this review for their potential to change practice or reinforce current evidence-based practice. One of the selected articles presents updated recommendations on the management of patients with atrial fibrillation (AF); the other 9 address topics such as albumin replacement in patients with severe sepsis, use of enteral statins for acute respiratory distress syndrome, fibrinolysis for patients with intermediate-risk pulmonary embolism, the use of unfractionated heparin versus bivalirudin for primary percutaneous coronary intervention, and early protocol-based care for septic shock.

CONCLUSION

There were many important additions to the critical care pharmacotherapy literature in 2014, including a joint guideline for the management of AF and reports of clinical trials.

Improved early right ventricular function recovery but increased complications with catheter-directed interventions compared with anticoagulation alone for submassive pulmonary embolism

OBJECTIVE

The purpose of this study was to determine the short-term and midterm outcomes of catheter-directed intervention (CDI) compared with anticoagulation (AC) alone in patients with submassive pulmonary embolism (sPE).

METHODS

This was a retrospective review of all patients treated for sPE between January 2009 and October 2014. Two groups were identified on the basis of the therapy: AC and CDI. End points included complications, mortality, and change in echocardiographic parameters. Standard statistical techniques were used.

RESULTS

There were 64 patients who received AC and 64 patients who received CDI (five were initially treated with AC but did not improve or worsened; six received ≤8 mg of tissue plasminogen activator). Most baseline characteristics, including the Pulmonary Embolism Severity Index, were similar among the AC and CDI groups. There was no difference in PE-related death (one in each group) or major bleeding events (three in the AC group, four in the CDI group), but CDIs had two additional procedural complications that required open heart surgery. CDIs showed significantly more minor bleeding events (6 vs 0; P = .028) and significantly shorter intensive care unit stay (2.7 ± 2.1 vs 5.6 ± 7.5 days; P = .04). The mean difference in right ventricular/left ventricular ratio from baseline to the first subsequent echocardiogram (within 30 days) showed a trend for higher reduction in favor of CDI (AC, 0.17 ± 0.12; CDI, 0.27 ± 0.15; P = .076). Between 3 and 8 months, significant improvement was evident within groups in all assessed right-sided heart echocardiographic parameters, but there was no difference between groups. Pulmonary hypertension (pulmonary artery pressure >40 mm Hg) was present in 7 of 15 of the AC group vs 6 of 19 of the CDI group (P = .484). During the follow-up, dyspnea or oxygen dependence, not existing before the index PE event, was recorded in 5 of 49 (10.2%) of the AC patients and 8 of 52 (15.4%) of the CDI patients (P = .556).

CONCLUSIONS

CDI for sPE can result in faster restoration of right ventricular function and shorter intensive care unit stay, but at the cost of a higher complication rate, with similar midterm outcomes compared with AC alone. A potential effect of CDI on mortality and pulmonary hypertension needs further investigation through larger studies.

What is the effect of venous thromboembolism and related complications on patient reported health-related quality of life? A meta-analysis

We conducted a meta-analysis of the literature to 1) assess the health-related quality of life for patients with a minimum follow-up of one year after an episode of pulmonary embolism (PE) or deep-vein thrombosis (DVT), and 2) to assess the HRQOL for patients who develop chronic thromboembolic pulmonary hypertension (CTEPH) and post thrombotic syndrome (PTS). PubMed, EMBASE, and the Cochrane Library were searched from inception to March 30, 2016. Data were pooled using random-effects meta-analysis, and heterogeneity was assessed with I² and Tau² tests. SF-12, SF-36, and VEINES-QOL were evaluated with pooled standardised mean difference (SMD) and 95 % confidence intervals (CI). Fourteen studies were included for meta-analysis. In patients who sustain a PE, physical health becomes impaired (p<0.001, 2 studies) but mental health appears to remain similar to population norms (p=0.069, 2 studies) after at least one year. Patients who develop CTEPH report worse physical (p<0.001, 1 study) and mental health (p=0.009, 1 study). In patients who suffer from a DVT, physical health (p=0.19, 9 studies), mental health (p=0.67, 9 studies), and disease specific quality of life (p=0.61, 8 studies) remain similar to population norms after at least one year. Patients who develop PTS, however, report worse physical health (p<0.001, 7 studies), mental health (p<0.001, 7 studies), and disease specific quality of life (p<0.001, 10 studies). These data can be used to educate patients during the shared decision making process that increasingly governs medical care today.

LEVEL OF EVIDENCE

II.

A Prospective, Single-Arm, Multicenter Trial of Ultrasound-Facilitated, Catheter-Directed, Low-Dose Fibrinolysis for Acute Massive and Submassive Pulmonary Embolism: The SEATTLE II Study

OBJECTIVES

This study conducted a prospective, single-arm, multicenter trial to evaluate the safety and efficacy of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis, using the EkoSonic Endovascular System (EKOS, Bothell, Washington).

BACKGROUND

Systemic fibrinolysis for acute pulmonary embolism (PE) reduces cardiovascular collapse but causes hemorrhagic stroke at a rate exceeding 2%.

METHODS

Eligible patients had a proximal PE and a right ventricular (RV)-to-left ventricular (LV) diameter ratio ≥0.9 on chest computed tomography (CT). We included 150 patients with acute massive (n = 31) or submassive (n = 119) PE. We used 24 mg of tissue-plasminogen activator (t-PA) administered either as 1 mg/h for 24 h with a unilateral catheter or 1 mg/h/catheter for 12 h with bilateral catheters. The primary safety outcome was major bleeding within 72 h of procedure initiation. The primary efficacy outcome was the change in the chest CT-measured RV/LV diameter ratio within 48 h of procedure initiation.

RESULTS

Mean RV/LV diameter ratio decreased from baseline to 48 h post-procedure (1.55 vs. 1.13; mean difference, -0.42; p < 0.0001). Mean pulmonary artery systolic pressure (51.4 mm Hg vs. 36.9 mm Hg; p < 0.0001) and modified Miller Index score (22.5 vs. 15.8; p < 0.0001) also decreased post-procedure. One GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries)-defined severe bleed (groin hematoma with transient hypotension) and 16 GUSTO-defined moderate bleeding events occurred in 15 patients (10%). No patient experienced intracranial hemorrhage.

CONCLUSIONS

Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis decreased RV dilation, reduced pulmonary hypertension, decreased anatomic thrombus burden, and minimized intracranial hemorrhage in patients with acute massive and submassive PE. (A Prospective, Single-arm, Multi-center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE) [SEATTLE II]; NCT01513759).

Fibrinolysis for Acute Care of Pulmonary Embolism in the Intermediate Risk Patient

Controversy over the role of fibrinolysis in patients with intermediate-risk pulmonary embolism (PE) has persisted because of the lack of adequately sized trials. The PEITHO study now allows a more precise estimate of the risk to benefit ratio of fibrinolysis in these patients. This trial enrolled patients with intermediate-risk PE who were randomized to receive heparin with either tenecteplase or placebo. Fibrinolysis was associated with a significant reduction in the combined end-point of death or hemodynamic decompensation, but also with a significant increase in the risk of major bleeding. The primary efficacy end-point occurred in 2.6 % of the patients in the tenecteplase group and in 5.6 % of the patients in the placebo group (OR, 0.44; 95 % CI, 0.23 to 0.87), conversely, major extracranial bleeding occurred in 6.3 % and 1.2 % in the tenecteplase and placebo groups, respectively (OR, 5.55; 95 % CI, 2.3 to 13.39) and stroke occurred in 2.4 % and in 0.2 % of the patients in the tenecteplase group and in the placebo group, respectively (OR, 12.10; 95 % CI, 1.57 to 93.39). No difference was observed for the risk of death alone and the risk of full-dose thrombolytic therapy outweighs its benefit in patients with intermediate-risk PE. Recent meta-analyses suggest that fibrinolysis may be associated with a slight reduction in overall mortality offset by an increase in major bleeding. Two pilot studies suggest that a reduced dose of fibrinolysis may produce significant hemodynamic improvement with a low risk of major bleeding. These options need to be evaluated in larger studies including patients with a higher risk of adverse outcome than those included in the PEITHO study.

Acute Pulmonary Embolism Network and Multidisciplinary Response Team Approach to Treatment

BACKGROUND

The ideal treatment strategy for acute pulmonary embolism (PE) remains a subject of debate. Treatment strategies vary based on numerous factors including the clinical scenario, hemodynamic variables, PE location, and personnel who are trained in advanced PE management therapies.

METHODS

Similar to an acute myocardial infarction network, we created a regional referral system called the Acute PE Network to facilitate the transport of patients with PE from referring facilities and improve access to advanced therapies. Simultaneously, we created a multidisciplinary PE response team (PERT), developed diagnostic protocols, and created a therapeutic pathway that includes the use of ultrasound-assisted catheter-directed thrombolysis (USAT) for submassive PE. Data were collected on patient characteristics, echocardiographic findings, and clinical outcomes for patients treated with USAT utilizing this pathway.

RESULTS

From January 2012 to May 2014, 31 patients who were treated with USAT for acute PE were identified. Fourteen of these patients were transferred through our Acute PE Network, whereas 17 patients presented directly to the emergency department. All patients were consulted upon by our PERT. Among those patients who had both pre-USAT and post-USAT echocardiograms performed for comparison (n = 19), right ventricular function improved or was preserved in 94% of patients, and right ventricular size improved or was preserved in 88% of patients.

CONCLUSIONS

Through the development of an Acute PE Network, with incorporation of a PERT and implementation of a critical care pathway, we report an innovative treatment approach to acute PE that includes utilization of USAT for submassive PE.

Contribution of fibrinolysis to the physical component summary of the SF-36 after acute submassive pulmonary embolism

Acute pulmonary embolism (PE) can diminish patient quality of life (QoL). The objective was to test whether treatment with tenecteplase has an independent effect on a measurement that reflects QoL in patients with submassive PE. This was a secondary analysis of an 8-center, prospective randomized controlled trial, utilizing multivariate regression to control for predefined predictors of worsened QoL including: age, active malignancy, history of PE or deep venous thrombosis (DVT), recurrent PE or DVT, chronic obstructive pulmonary disease and heart failure. QoL was measured with the physical component summary (PCS) of the SF-36. Analysis included 76 patients (37 randomized to tenecteplase, 39 to placebo). Multivariate regression yielded an equation f(8, 67), P < 0.001, with R(2) = 0.303. Obesity had the largest effect on PCS (β = -8.6, P < 0.001), with tenecteplase second (β = 4.73, P = 0.056). After controlling for all interactions, tenecteplase increased the PCS by +5.37 points (P = 0.027). In patients without any of the defined comorbidities, the coefficient on the tenecteplase variable was not significant (-0.835, P = 0.777). In patients with submassive PE, obesity had the greatest influence on QoL, followed by use of fibrinolysis. Fibrinolysis had a marginal independent effect on patient QoL after controlling for comorbidities, but was not significant in patients without comorbid conditions.