Efficacy and safety of 2-hour urokinase regime in acute pulmonary embolism: a randomized controlled trial

Exogenous Urokinase Inhibits Proteasomal Degradation of Its Cognate Urokinase Plasminogen Activator Receptor

Acute pulmonary embolism (APE) is a debilitating condition with high incidence and mortality rates. APE is widely treated with the serine protease urokinase or urokinase-type plasminogen activator (uPA) that functions by resolving blood clots via catalyzing the conversion of plasminogen to plasmin. Treatment with recombinant uPA has been shown to increase endogenous expression of uPA and its cognate receptor, uPAR; however, the mechanisms for this induction are not known. Using an in vitro hypoxia/reoxygenation model in bronchial epithelial BEAS-2B cells, we show that induction of hypoxia/reoxygenation induces apoptosis and increases secretion of tumor necrosis factor–alpha, brain natriuretic peptide, and fractalkine, which are attenuated when treated with exogenous uPA. Induction of hypoxia/reoxygenation resulted in decreased expression of uPAR on cell surface without any significant changes in its messenger RNA expression, highlighting post-transcriptional regulatory mechanisms. Determination of uPAR protein half-life using cycloheximide showed treatment with uPA significantly increased its half-life (209.6 ± 0.2 min from 48.2 ± 2.3 min). Hypoxia/reoxygenation promoted the degradation of uPAR. Inhibition of proteasome-mediated degradation using MG-132 and lactacystin revealed that uPAR was actively degraded when hypoxia/reoxygenation was induced and that it was reversed when treated with exogenous uPA. Determination of the proteolytic activity of 20S proteasome showed a global increase in ubiquitin–proteasome activation without an increase in proteasome content in cells subjected to hypoxia/reoxygenation. Our results cumulatively reveal that uPAR is actively degraded following hypoxia/reoxygenation, and the degradation was significantly weakened by exogenous uPA treatment. Given the importance of the uPA/uPAR axis in a multitude of pathophysiological contexts, these findings provide important yet undefined mechanistic insights.

MicroRNA 449a can Attenuate Protective Effect of Urokinase Against Pulmonary Embolism

Acute pulmonary embolism (APE) is a disabling diseases with high incidence rate and mortality rate. Although with high specificity, D-Dimer lacks specificity to assess APE, hence additional diagnostic and prognostic biomarkers are necessary. APE is widely treated with serine protease urokinase or urokinase-type plasminogen activator (uPA), which act as a catalyst for conversion of plasminogen to plasmin to resolve blood clots. However, it is unknown the role of differential expression of microRNAs (miRNAs) in protective effect of uPA against APE. Hence, we performed miRNA profiling in a hypoxia/reoxygenation (H/R) model of bronchial epithelial BEAS-2B cells in vitro and a APE mice model in vivo. Our analysis revealed that miR-34a-5p, miR-324-5p, miR-331-3p are upregulated with H/R or APE induction, whereas miR-429, miR-491-5p, and miR-449a are downregulated. The differential expression of the miRNAs was attenuated to levels comparable to control by treatment with uPA both in vitro and in vivo. In situ target prediction and analysis of potential functions of the target genes showed that the enrichment of biological processes and pathways were related to cell growth, proliferation, and inflammation. Ectopic overexpression of miR-449a using a mimic completely attenuated the protective effect of uPA in the H/R model in vitro. These results provide a group of miRNAs that could be used as markers, and the modulation of these miRNAs might have potential therapeutic benefits in patients with APE, which need to be validated in additional studies in humans.

Thrombolytic therapy for pulmonary embolism

BACKGROUND

Thrombolytic therapy is usually reserved for people with clinically serious or massive pulmonary embolism (PE). Evidence suggests that thrombolytic agents may dissolve blood clots more rapidly than heparin and may reduce the death rate associated with PE. However, there are still concerns about the possible risk of adverse effects of thrombolytic therapy, such as major or minor haemorrhage. This is the fourth update of the Cochrane review first published in 2006.

OBJECTIVES

To assess the effects of thrombolytic therapy for acute pulmonary embolism.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 17 August 2020. We undertook reference checking to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared thrombolytic therapy followed by heparin versus heparin alone, heparin plus placebo, or surgical intervention for people with acute PE (massive/submassive). We did not include trials comparing two different thrombolytic agents or different doses of the same thrombolytic drug.

DATA COLLECTION AND ANALYSIS

Two review authors (ZZ, QH) assessed the eligibility and risk of bias of trials and extracted data. We calculated effect estimates using the odds ratio (OR) with a 95% confidence interval (CI) or the mean difference (MD) with a 95% CI. The primary outcomes of interest were death, recurrence of PE and haemorrhagic events. We assessed the certainty of the evidence using GRADE criteria.

MAIN RESULTS

We identified three new studies for inclusion in this update. We included 21 trials in the review, with a total of 2401 participants. No studies compared thrombolytics versus surgical intervention. We were not able to include one study in the meta-analysis because it provided no extractable data. Most studies carried a high or unclear risk of bias related to randomisation and blinding. Meta-analysis showed that, compared to control (heparin alone or heparin plus placebo), thrombolytics plus heparin probably reduce both the odds of death (OR 0.58, 95% CI 0.38 to 0.88; 19 studies, 2319 participants; low-certainty evidence), and recurrence of PE (OR 0.54, 95% CI 0.32 to 0.91; 12 studies, 2050 participants; low-certainty evidence). Effects on mortality weakened when six studies at high risk of bias were excluded from analysis (OR 0.71, 95% CI 0.45 to 1.13; 13 studies, 2046 participants) and in the analysis of submassive PE participants (OR 0.61, 95% CI 0.37 to 1.02; 1993 participants). Effects on recurrence of PE also weakened after removing one study at high risk of bias for sensitivity analysis (OR 0.60, 95% CI 0.35 to 1.04; 11 studies, 1949 participants). We downgraded the certainty of evidence to low because of 'Risk of bias' concerns. Major haemorrhagic events were probably more common in the thrombolytics group than in the control group (OR 2.84, 95% CI 1.92 to 4.20; 15 studies, 2101 participants; moderate-certainty evidence), as were minor haemorrhagic events (OR 2.97, 95% CI 1.66 to 5.30; 13 studies,1757 participants; low-certainty evidence). We downgraded the certainty of the evidence to moderate or low because of 'Risk of bias' concerns and inconsistency. Haemorrhagic stroke may occur more often in the thrombolytics group than in the control group (OR 7.59, 95% CI 1.38 to 41.72; 2 studies, 1091 participants). Limited data indicated that thrombolytics may benefit haemodynamic outcomes, perfusion lung scanning, pulmonary angiogram assessment, echocardiograms, pulmonary hypertension, coagulation parameters, composite clinical outcomes, need for escalation and survival time to a greater extent than heparin alone. However, the heterogeneity of the studies and the small number of participants involved warrant caution when interpreting results. The length of hospital stay was shorter in the thrombolytics group than in the control group (mean difference (MD) -1.40 days, 95% CI -2.69 to -0.11; 5 studies, 368 participants). Haemodynamic decompensation may occur less in the thrombolytics group than in the control group (OR 0.36, 95% CI 0.20 to 0.66; 3 studies, 1157 participants). Quality of life was similar between the two treatment groups. None of the included studies provided data on post-thrombotic syndrome or on cost comparison.

AUTHORS' CONCLUSIONS

Low-certainty evidence suggests that thrombolytics may reduce death following acute pulmonary embolism compared with heparin (the effectiveness was mainly driven by one trial with massive PE). Thrombolytic therapy may be helpful in reducing the recurrence of pulmonary emboli but may cause more major and minor haemorrhagic events, including haemorrhagic stroke. More studies of high methodological quality are needed to assess safety and cost effectiveness of thrombolytic therapy for people with pulmonary embolism.

Thrombolytic therapy for pulmonary embolism

BACKGROUND

Thrombolytic therapy is usually reserved for patients with clinically serious or massive pulmonary embolism (PE). Evidence suggests that thrombolytic agents may dissolve blood clots more rapidly than heparin and may reduce the death rate associated with PE. However, there are still concerns about the possible risk of adverse effects of thrombolytic therapy, such as major or minor haemorrhage. This is the third update of the Cochrane review first published in 2006.

OBJECTIVES

To assess the effects of thrombolytic therapy for acute pulmonary embolism.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 16 April 2018. We undertook reference checking to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared thrombolytic therapy followed by heparin versus heparin alone, heparin plus placebo, or surgical intervention for patients with acute PE. We did not include trials comparing two different thrombolytic agents or different doses of the same thrombolytic drug.

DATA COLLECTION AND ANALYSIS

Two review authors (JY, QH) assessed the eligibility and quality of trials and extracted data. We calculated effect estimates using the odds ratio (OR) with 95% confidence interval (CI) or the mean difference (MD) with 95% CI. We assessed the quality of the evidence using GRADE criteria.

MAIN RESULTS

We identified no new studies for inclusion in this 2018 update. We included in the review 18 trials with a total of 2197 participants. We were not able to include one study in the meta-analysis because it provided no data that we could extract. Most of the studies carried a high risk of bias because of high or unclear risk related to randomisation and blinding. Meta-analysis showed that, compared with heparin alone, or heparin plus placebo, thrombolytics plus heparin can reduce the odds of death (OR 0.57, 95% CI 0.37 to 0.87, 2167 participants, P = 0.01, low-quality evidence) and recurrence of PE (OR 0.51, 95% CI 0.29 to 0.89, 1898 participants, P = 0.02, low-quality evidence). Effects on mortality weakened when we excluded from analysis four studies at high risk of bias (OR 0.66, 95% CI 0.42 to 1.06, 2054 participants, P = 0.08). The incidence of major and minor haemorrhagic events was higher in the thrombolytics group than in the control group (OR 2.90, 95% CI 1.95 to 4.31, 1897 participants, P < 0.001, low-quality evidence; OR 3.09, 95% CI 1.58 to 6.06, 1553 participants, P = 0.001, very low-quality evidence, respectively). We downgraded the quality of the evidence to low or very low because of design limitations, potential influence of pharmaceutical companies, and small sample sizes. Length of hospital stay (mean difference (MD) -0.89, 95% CI -3.13 to 1.34) and quality of life were similar between the two treatment groups. Limited information from a small number of trials indicated that thrombolytics may improve haemodynamic outcomes, perfusion lung scanning, pulmonary angiogram assessment, echocardiograms, pulmonary hypertension, coagulation parameters, clinical outcomes, and survival time to a greater extent than heparin alone. However, the heterogeneity of the studies and the small number of participants involved warrant caution when results are interpreted. Similarily, fewer participants from the thrombolytics group required escalation of treatment. None of the included studies reported on post-thrombotic syndrome or compared the costs of different treatments.

AUTHORS' CONCLUSIONS

Low-quality evidence suggests that thrombolytics reduce death following acute pulmonary embolism compared with heparin. The included studies used a variety of thrombolytic drugs. Thrombolytic therapy may be helpful in reducing the recurrence of pulmonary emboli but may cause major and minor haemorrhagic events and stroke. More high-quality, blinded randomised controlled trials assessing safety and cost-effectiveness of therapies for pulmonary embolism are required.

Efficacy and safety of low-dose urokinase for the treatment of hemodynamically stable AECOPD patients with acute pulmonary thromboembolism

PURPOSE

The aim of this study was to assess the incidence of pulmonary thromboembolism (PTE) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD),and to evaluate the efficacy and safety of low-dose urokinase (UK) thrombolysis therapy when treating hemodynamically stable AECOPD patients with acute PTE (AECOPD-PTE).

METHODS

A total of 419 AECOPD patients, including 96 AECOPD-PTE, were enrolled. A total of 30 AECOPD-PTE patients were collected retrospectively, and 66 AECOPD-PTE patients were prospectively divided into anticoagulation-only, low-dose UK and standard-dose UK groups. Follow-up 1 year, we evaluated the efficacy and safety of low-dose UK therapy for hemodynamically stable AECOPD-PTE patients.

RESULTS

The incidence of PTE in AECOPD patients was 22.9% (96/419), which increased with COPD severity degree ranging from 3.5% (2/57) in mild, 13.6% (19/140) in moderate and 33.8% (75/222) in severe subgroups (P < .05). In the prospective study, the total effective rate of low-dose UK group 97.2% (35/36) was higher than that in anticoagulation 75.0% (12/16) and standard-dose UK group 78.6% (11/14) respectively (P < .05). In the follow-up, the adverse events rate in low-dose UK group 8.3% (3/36) was significantly lower than that in anticoagulation group 25.0% (4/16) and standard-dose UK group 71.4% (10/14) respectively (P < .05). In addition, the mean PTE recurrence time of low-dose UK group (9.0 ± 0) months was longer than anticoagulation group (2.0 ± 1.41) months (P < .05). AECOPD relapse time in anticoagulation, low-dose UK and standard-dose UK groups corresponding to (8.5 ± 2.12), (9.0 ± 0) and (8.8 ± 3.40) months were compared with no significant difference (P > .05).

CONCLUSIONS

The incidence of PTE in AECOPD patients was 22.9%, especially with higher occurrence rate in severe COPD. Compared with anticoagulation-only therapy, low-dose UK treatment (500 000 IU/day for 5-7 days) could obtain a better efficacy and safety in hemodynamically stable AECOPD patients with acute PTE, corresponding with a higher effective rate (97.2%) and lower adverse events rate (8.3%) respectively.

Thrombolytic therapy for pulmonary embolism

BACKGROUND

Thrombolytic therapy (powerful anticoagulation drugs) is usually reserved for patients with clinically serious or massive pulmonary embolism (PE). Evidence suggests that thrombolytic agents may dissolve blood clots more rapidly than heparin and reduce the death rate associated with PE. However, there are still concerns about the possible risk of adverse effects of thrombolytic therapy, such as major or minor haemorrhages. This is the second update of the Cochrane review first published in 2006.

OBJECTIVES

To assess the effects of thrombolytic therapy in patients with acute pulmonary embolism.

SEARCH METHODS

For this update the Cochrane Vascular Group searched their Specialised Register (last searched September 2014) and the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (last searched Issue 8, 2014). We also searched individual trial collections and private databases, along with bibliographies of relevant articles. We handsearched relevant medical journals.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared thrombolytic therapy followed by heparin versus heparin alone, heparin plus placebo or surgical intervention in patients with acute PE. We did not include trials comparing two different thrombolytic agents or different doses of the same thrombolytic drug.

DATA COLLECTION AND ANALYSIS

Two authors (BD and QH) assessed the eligibility and quality of trials and extracted data.

MAIN RESULTS

We identified 18 trials with a total of 2197 participants for inclusion in the review. We were not able to include one study in the meta-analysis because it had no data to extract. Most of the studies carried a high risk of bias because of high or unclear risk relating to randomisation and blinding. Meta-analysis showed that, compared with heparin alone, or heparin plus placebo, thrombolytics plus heparin can reduce the odds of death (odds ratio (OR) 0.57, 95% confidence interval (CI) 0.37 to 0.87, P = 0.02, low quality evidence) and recurrence of PE (OR 0.51; 95% CI 0.29 to 0.89, P = 0.02, low quality evidence). The effects of death weakened when we excluded four studies at high risk of bias from analysis: OR 0.66, 95% CI 0.42 to 1.06, P = 0.08. The incidence of major and minor haemorrhagic events was higher in the thrombolytics group than in the control group, and this difference was statistically significant (OR 2.90, 95% CI 1.95 to 4.31, P < 0.001, low quality evidence; OR 3.09, 95% CI 1.58 to 6.06, P = 0.001, very low quality evidence, respectively). Length of hospital stay (mean difference (MD) -1.35, 95% CI -4.27 to 1.58) and quality of life were similar between the two treatment groups. Stroke was reported in one study and occurred more often in the thrombolytics group than in the control group, although the confidence interval was wide (OR 12.10, 95% CI 1.57 to 93.39). Limited information from a small number of trials indicated that thrombolytics may improve haemodynamic outcomes, perfusion lung scanning, pulmonary angiogram assessment, echocardiograms, pulmonary hypertension, coagulation parameters, clinical outcomes and survival time to a greater extent than heparin alone. However, the heterogeneity of the studies and small number of participants involved warrant caution when interpreting results. Similarily, fewer patients from the thrombolytics group required escalation of treatment. None of the included studies reported on post-thrombotic syndrome or compared the cost of the different treatments.

AUTHORS' CONCLUSIONS

There is low quality evidence that thrombolytics reduce death following acute pulmonary embolism compared with heparin. Furthermore, thrombolytic therapies included in the review were heterogeneous. Thrombolytic therapy may be helpful in reducing the recurrence of pulmonary emboli but may cause more major and minor haemorrhagic events and stroke. More high quality double blind RCTs assessing safety and cost-effectiveness are required.

Inverse relationship of bleeding risk with clot burden during pulmonary embolism treatment with LMW heparin

INTRODUCTION

Clinically relevant bleeding occurs three times as frequently as recurrent venous thromboembolism in the modern early treatment of pulmonary embolism (PE) with fixed-dose, unmonitored anticoagulants. Unfractionated heparin (UFH) is monitored and adjusted to assure efficacy and minimize bleeding risk, but low molecular weight heparin (LMWH) is not. PE requires more anticoagulant than isolated deep venous thrombosis. Speculating that PE with low clot burden could lead to excess bleeding with unadjusted LMWH treatment but not with UFH, we compared PE patients receiving either UFH or LMWH with high and low clot burden for clinically significant bleeding in an observational study.

MATERIALS AND METHODS

Patients with acute PE at multiple Chinese teaching hospitals had been randomized to UFH or LMWH for initial treatment. These treatment cohorts had baseline measurement of pulmonary artery obstruction (PAO) score, which was prospectively separated into quartiles, lowest to highest PAO. All patients were followed for bleeding episodes, which were subsequently analyzed by quartile of PAO.

RESULTS

Two hundred seventy-four patients divided between the two groups had similar efficacy and safety outcomes (12 clinically significant bleeds in the UFH group vs 15 in the LMWH group). LMWH recipients with the smallest clot burdens (lowest PAO quartiles) had highest bleeding rates (Cochran-Armitage trend test, P trend = 0.048), but there was no such trend for UFH recipients.

CONCLUSIONS

For UFH, excess anticoagulant pro-hemorrhagic potential is down-adjusted via activated partial thromboplastin time monitoring, but for LMWH it is not. For PE patients at high bleeding risk, UFH may be safer if the clot burden is small.

Extensive heterogeneity of human urokinase, as detected by two-dimensional mapping

Urokinase (uPA, urinary plasminogen activator) is a serine protease belonging to the peptidase S1 family. Specifically, uPA cleaves the zymogen plasminogen into the active form (plasmin), which then degrades the fibrin clots. It is widely used as a fibrinolytic agent in thrombolytic therapy and it is also used clinically as a thrombolytic agent. It can be administered to improve the drainage of complicated pleural effusions and empyemas and it is the most effective drug in myocardial infarction. The enzyme was originally identified in human urine for its ability to catalyze the transformation of plasminogen into its active form (plasmin), which degrades fibrin and extracellular matrix components. The present report deals with the analysis and characterization of this preparation.

Aspect of thrombolytic therapy: a review

Thrombolytic therapy, also known as clot busting drug, is a breakthrough treatment which has saved untold lives. It has been used in the clinical area to treat venous and arterial thromboembolic complaints which are a foremost cause of death. In 1761, Morgagni lead the way of thrombolytic therapy. Now day's different types of thrombolytic drugs are currently available in market: alteplase, anistreplase, urokinase, streptokinase, tenecteplase, and so forth. Thrombolytic therapy should be given with maintaining proper care in order to minimize the risk of clinically important bleeding as well as enhance the chances of successfully thrombolysis of clot. These cares include preinfusion care, during the infusion care, and postinfusion care. Besides proper knowledge of contraindication, evolutionary factor, and combination of drug is essential for successful thrombolytic therapy. In these review we discussed about these aspect of thrombolytic therapy.

Recombinant tissue plasminogen activator plus heparin compared with heparin alone for patients with acute submassive pulmonary embolism: one-year outcome

Objective

To evaluate the long-term effects of thrombolysis on patients with submassive pulmonary embolism (PE).

Methods

Data of 136 patients with acute submassive PE and low risk of bleeding were prospectively collected from January 2005 to October 2011 in a single medical center. Patients received recombinant tissue plasminogen activator (r-tPA) plus low molecular weight heparin (LMWH, TT group, n = 79) or LMWH alone (AT group, n = 57), depending on treating physician's recommendation and patient's preference. Echocardiography was performed at admission, 24 h, 6 and 12 months to evaluate right ventricular function. Computed tomography pulmonary angiography (CTPA) and lung perfusion scan were performed on admission, at 7 days, 6 and 12 months to evaluate clot burden.

Results

Seventy-nine patients received r-tPA plus LMWH (TT group) while 57 received LMWH alone (AT group). The baseline characteristics and risk factors did not differ between the two groups. Respiratory rate, heart rate, and systolic blood pressure improved within two hours in both groups. Systolic pulmonary arterial pressure and tricuspid regurgitation improved to a greater extent in the TT group at 24 h, and at 12 months (P < 0.001), as compared to those in the AT group. At one week, and 12 months, clot burden decreased more in AT group, as compared to that in AT group (P < 0.001). There was no death due to bleeding in both groups. Recurrent PE were similar in both groups (2.5% in TT vs. 1.8% in AT). The rates of minor hemorrhages were 6.3% in TT group and 1.8% in AT group (P < 0.05).

Conclusion

In submassive PE patient who has low risk of bleeding, thrombolysis plus anticoagulation can lead to greater improvement of right ventricular dysfunction and clot burden reduction as compared to anticoagulation therapy alone.

Systematic review and meta-analysis for thrombolysis treatment in patients with acute submassive pulmonary embolism

PURPOSE

The aim of this systematic review was to evaluate the efficacy and safety of thrombolytic treatment in patients with submassive pulmonary embolism (PE).

METHODS

An electronic search was carried out based on the databases from MEDLINE, Embase, Science Citation Index (SCI), and the Cochrane Library. We included prospective, randomized, and clinical trials in thrombolysis with heparin alone in adults who had evidence of right ventricular dysfunction and normotension. The main endpoints consist of mortality, recurrent PE, and bleeding risk. The relative risk (RR) and the relevant 95% confidence intervals were determined by the dichotomous variable.

RESULTS

Only seven studies involving 594 patients met the inclusion criteria for further review. The cumulative effect of thrombolysis, compared with intravenous heparin, demonstrated no statistically significant difference in mortality (2.7% versus 4.3%; RR=0.64 [0.29-1.40]; P=0.27) or recurrent PE (2% versus 5%; RR=0.44 [0.19-1.05]; P=0.06). Thrombolytic therapy did not increase major hemorrhage compared with intravenous heparin (4.5% versus 3.3%; RR=1.16 [0.51-2.60]; P=0.73), but it was associated with an increased minor hemorrhage (41% versus 9%; RR=3.91 [1.46-10.48]; P=0.007).

CONCLUSION

Compared with heparin alone, neither mortality nor recurrent PE is reduced by thrombolysis in patients with submassive PE, and it does not reveal an increasing risk of major bleeding. In addition, thrombolysis also produces the increased risk of minor bleeding; however, no sufficient evidence verifies the thrombolytic benefit in this review, because the number of patients enrolled in the trials is limited. Therefore, a large, double-blind clinical trial is required to prove the outcomes of this meta-analysis.

The specialty of pulmonary vascular medicine in China: historical development and future directions

Over the past 40 years, Chinese experts have made great progress on research, diagnosis, and therapy of pulmonary vascular disease, including pulmonary embolism and pulmonary hypertension. These theoretical and clinical advances have increased public awareness about this group of conditions, which are associated with significant morbidity and mortality in China and worldwide. With its theoretical basis combining knowledge from cardiovascular and pulmonary medicine, pulmonary vascular disease has developed into a separate, unique specialty in hospitals across China and worldwide. This article will provide a short historical perspective but also an outlook into the future of this exciting novel discipline. We provide a Chinese perspective, based on our research and clinic experience over the past decades.

Rationale and methodology for a multicentre randomised trial of fibrinolysis for pulmonary embolism that includes quality of life outcomes

BACKGROUND

Submassive pulmonary embolism (PE) has a low mortality rate but can degrade functional capacity.

OBJECTIVE

The present study aims to provide rationale, methodology, and initial findings of a multicentre, randomised trial of fibrinolysis for PE that used a composite end-point, including quality of life measures.

METHODS

This investigator-initiated study was funded by a contract between a corporate partner and the investigator's hospital (the prime site). The investigator was the Food and Drug Administration (FDA) sponsor. The prime site subcontracted, indemnified, and trained consortia members. Consenting, normotensive patients with PE and right ventricular strain (by echocardiography or biomarkers) received low-molecular-weight heparin and random assignment to a single bolus of tenecteplase or placebo in double-blinded fashion. The outcomes were: (i) in-hospital rate of intubation, vasopressor support, and major haemorrhage, or (ii) at 90 days, death, recurrent PE, or composite that defined poor quality of life (echocardiography, 6 min walk test and surveys). The planned sample size was n = 200.

RESULTS

Eight sites enrolled 87 patients over 5 years. The ratio of patients screened for each enrolled was 7.4 to 1, equating to 11 h screening time per patient enrolled. Primary barrier to enrolment was the cost of screening. Two patients died (2.5%, 95%CI [0-8%]), one developed shock, but 18 (22%, 95%CI: [13-30%]) had a poor quality of life.

CONCLUSIONS

An investigator-initiated, FDA-regulated, multicentre trial of fibrinolysis for submassive PE was conducted, but was limited by screening costs and a low mortality rate. Quality of life measurements might represent a more important patient-centred end-point.

High dose urokinase against massive pulmonary embolism in nephrotic syndrome

Patients with nephrotic syndrome carry a high risk of pulmonary embolism due to the abnormalities in coagulation and fibrinolysis. Thrombolytic therapy for critical pulmonary embolism in nephrotic syndrome patients was rarely reported and remains controversial in the regimen selection so far. We reported a case of fatal pulmonary embolism, complicating in hepatitis B virus-associated nephrotic syndrome. The patient presented with chest pain, hemoptysis and shortness of breath on admission and his initial vital signs showed a high risk of developing hypotension. Urgent radiological examinations confirmed massive embolisms in bilateral pulmonary arteries. Prompt thrombolytic therapy was performed right after the diagnosis of pulmonary embolism with an intravenous infusion of urokinase (20 000 U/kg) in 2 h. Complete resolution of pulmonary embolism was achieved after urokinase administration and the patient was discharged in good conditions. This report highlighted the efficacy and safety of prompt thrombolytic therapy with urokinase for nephrotic syndrome patients presented with massive pulmonary embolism. In this study, we also briefly discuss the recent findings on the current state of urokinase in the clinical practice of thrombolysis.

Respiratory medicine in China: progress, challenges, and opportunities

The past century witnessed a rapid development of respiratory medicine in China. The major burden of respiratory disease has shifted from infectious diseases to chronic noninfectious diseases. Great achievements have been made in improving the national standard of clinical management of various respiratory diseases and in smoking control. The specialty of respiratory medicine is expanding into pulmonary and critical care medicine. Nevertheless, respiratory diseases remain a major public health problem, with new challenges such as air pollution and nosocomial infections. This review describes the history, accomplishments, new challenges, and opportunities in respiratory medicine in China.

Antithrombotic therapy for VTE disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

This article addresses the treatment of VTE disease.

METHODS

We generated strong (Grade 1) and weak (Grade 2) recommendations based on high-quality (Grade A), moderate-quality (Grade B), and low-quality (Grade C) evidence.

RESULTS

For acute DVT or pulmonary embolism (PE), we recommend initial parenteral anticoagulant therapy (Grade 1B) or anticoagulation with rivaroxaban. We suggest low-molecular-weight heparin (LMWH) or fondaparinux over IV unfractionated heparin (Grade 2C) or subcutaneous unfractionated heparin (Grade 2B). We suggest thrombolytic therapy for PE with hypotension (Grade 2C). For proximal DVT or PE, we recommend treatment of 3 months over shorter periods (Grade 1B). For a first proximal DVT or PE that is provoked by surgery or by a nonsurgical transient risk factor, we recommend 3 months of therapy (Grade 1B; Grade 2B if provoked by a nonsurgical risk factor and low or moderate bleeding risk); that is unprovoked, we suggest extended therapy if bleeding risk is low or moderate (Grade 2B) and recommend 3 months of therapy if bleeding risk is high (Grade 1B); and that is associated with active cancer, we recommend extended therapy (Grade 1B; Grade 2B if high bleeding risk) and suggest LMWH over vitamin K antagonists (Grade 2B). We suggest vitamin K antagonists or LMWH over dabigatran or rivaroxaban (Grade 2B). We suggest compression stockings to prevent the postthrombotic syndrome (Grade 2B). For extensive superficial vein thrombosis, we suggest prophylactic-dose fondaparinux or LMWH over no anticoagulation (Grade 2B), and suggest fondaparinux over LMWH (Grade 2C).

CONCLUSION

Strong recommendations apply to most patients, whereas weak recommendations are sensitive to differences among patients, including their preferences.

[Pulmonary thromboembolism]

Pulmonary thromboembolism is a frequent disease in emergency departments and often poses a diagnostic challenge that requires appropriate strategies. Clinical information, laboratory tests such as a D-dimer and imaging techniques such as computed tomography (CT) angiography, ventilation-perfusion scintigraphy or echocardiography help to establish clinical probability and the severity of the disease. With all this information, risk scores can be constructed, such as the Pulmonary Embolism Severity Index (PESI) score, which has high sensitivity in predicting mortality. Treatment should be started immediately with heparin, usually low molecular weight heparin. If the patient is at high risk, thrombolytic therapy is indicated, although possible contraindications should be thoroughly assessed. Supportive treatment may be considered in a few patients.