Thrombolysis Versus Anticoagulation for the Initial Treatment of Moderate Pulmonary Embolism: A Meta-Analysis of Randomized Controlled Trials

Assessment of lytic therapy effect in patients with intermediate-high risk pulmonary embolism for prevention of chronic thromboembolic pulmonary hypertension: A randomized, double-blind trial

Background and Aims

This study aims to compare the effectiveness of thrombolytic therapy and anticoagulation in preventing chronic thromboembolic pulmonary hypertension (CTEPH).

Method

A total of 60 patients with intermediate-high risk pulmonary embolism (PE) were randomly assigned to receive either thrombolytic therapy (n = 30) or anticoagulation (n = 30).

Results

Echocardiographic assessments demonstrated no significant differences between the two treatment approaches in terms of right ventricular size (RVS) (on discharge in thrombolytic group: 31.17 ± 3.43 vs. anticoagulant group: 32.73 ± 5.27, p = 0.912), tricuspid annular plane systolic excursion (TAPSE) (on discharge in thrombolytic group: 17.66 ± 2.39 vs. anticoagulant group: 16.73 ± 2.93, p = 0.290), and systolic pulmonary artery pressure (SPAP) (on discharge in thrombolytic group: 32.93 ± 9.73 vs. anticoagulant group: 34.46 ± 9.30, p = 0.840). However, significant changes were observed in all assessed parameters within each treatment group (p < 0.001). The 6-month follow-up showed no significant difference between the two groups in terms of CTEPH incidence (p = 0.781) or functional class of the patients (p = 0.135).

Conclusion

Based on the findings of this study, neither thrombolytic therapy nor anticoagulation demonstrated superiority over the other in reducing adverse outcomes associated with intermediate-high risk PE, including right ventricular size, SPAP, TAPSE, or CTEPH.

Safety and efficacy of clot-dissolving therapies for submassive pulmonary embolism: A network meta-analysis of randomized controlled trials

BACKGROUND

Acute pulmonary embolism (PE) is a serious condition that needs quick and effective treatment. Anticoagulation therapy is the usual care for most PE patients but may not work well for higher-risk ones. Thrombolysis breaks the clot and improves blood flow. It can be given systemically or locally. Ultrasound-assisted catheter-directed thrombolysis (USAT) is a new technique that boosts clot-busting drugs. This network meta-analysis compares death, bleeding, and benefits of four treatments in acute submassive PE.

METHODS

We comprehensively searched relevant databases up to July 2023 for RCTs. The outcomes encompassed all-cause mortality, major and minor bleeding, PE recurrence, and hospital stay duration. Bayesian network meta-analysis computed odds ratios (OR) and 95 % CI estimates.

RESULTS

In this network meta-analysis of 23 RCTs involving 2521 PE patients, we found that SCDT had the most favorable performance for mortality, as it had the lowest odds ratio (OR) among the four interventions (OR 5.41e-42; 95 % CI, 5.68e-97, 1.37e-07). USAT had the worst performance for major bleeding, as it had the highest OR among the four interventions (OR 4.73e+04; 95 % CI, 1.65, 9.16e+13). SCDT also had the best performance for minor bleeding, as it had the lowest OR among the four interventions (OR 5.68e-11; 95 % CI, 4.97e-25, 0.386).

CONCLUSION

Our meta-analysis suggests that SCDT is the most effective treatment intervention in improving the risks of All-cause mortality and bleeding. Thrombolytic therapy helps in improving endpoints including the risk of PE recurrence and the duration of hospital stay.

Reduced-Dose Thrombolysis in Acute Pulmonary Embolism A Systematic Review

Pulmonary embolism (PE) is the third-leading cause of cardiovascular mortality and the second-leading cause of death in cancer patients. The clinical efficacy of thrombolysis for acute PE has been proven, yet the therapeutic window seems narrow, and the optimal dosing for pharmaceutical reperfusion therapy has not been established. Higher doses of systemic thrombolysis inevitably associated with an incremental increase in major bleeding risk. To date, there is no high-quality evidence regarding dosing and infusion rates of thrombolytic agents to treat acute PE. Most clinical trials have focused on thrombolysis compared with anticoagulation alone, but dose-finding studies are lacking. Evidence is now emerging that lower-dose thrombolytic administered through a peripheral vein is efficacious in accelerating thrombolysis in the central pulmonary artery and preventing acute right heart failure, with reduced risk for major bleeding. The present review will systematically summarize the current evidence of low-dose thrombolysis in acute PE.

Comparison of Efficacy and Safety between Thrombolysis Plus Anticoagulation vs. Anticoagulation Alone for the Treatment of Acute Submassive Pulmonary Embolism: A Systematic Review and Meta-analysis

OBJECTIVE

The objective of this study is to compare the efficacy and safety of thrombolysis plus anticoagulant therapy vs. anticoagulant therapy alone in acute submassive pulmonary embolism (PE).

MATERIALS AND METHODS

The PubMed, Embase, and Cochrane Library databases were searched for randomized clinical trials comparing thrombolytic therapy and anticoagulation vs. anticoagulation alone in acute submassive PE patients from 1 Jan 1980 to 20 Jan 2021, with no drug or dose restrictions. Data on upgraded treatment of clinical deterioration, all-cause mortality, PE recurrence and bleeding events were extracted and analyzed using Revman 5.3 software.

RESULTS

A total of 10 randomized controlled trials involving 1871 patients were included in the study after screening. In terms of efficacy, thrombolysis combined with anticoagulant therapy reduced the need for upgrading treatment (3.6 vs. 10.9%, risk ratio (RR) 0.36, 95% confidence interval (CI) 0.24- 0.54, p<0.00001) and PE recurrence (0.8 vs. 2.9%, RR 0.33, 95% CI 0.16-0.69, p=0.003) in patients with acute submassive PE. Compared with anticoagulant therapy alone, the concomitant use of thrombolysis was associated with lower all-cause mortality (1.3 vs. 3.0%, RR 0.47, 95% CI 0.26-0.87, p=0.02), but it increased minor bleeding rate (31.4 vs. 8.4%, RR 3.71, 95% CI 2.82-4.88, p<0.0001) and major bleeding rate (8.8 vs. 2.6%, RR 3.35, 95%CI 2.03-5.54, p<0.0001).

CONCLUSION

The use of thrombolysis plus anticoagulant therapy in acute submassive PE was negatively associated with patients requiring escalation of treatment, PE recurrence, and all-cause mortality, but it was positively associated with bleeding.

Mitigating Disputes Originated by Multiple Discordant Systematic Reviews and Meta-Analyses: A Survey of Methodologists and Clinicians

Background

Overlapping systematic reviews (SRs) are increasingly frequent in the medical literature. They can easily generate discordant evidence, as estimates of effect sizes and their interpretation might differ from one source to another.

Objective

To analyze how methodologists and clinicians make a decision when faced with discordant evidence formalized in structured tables.

Methods

We conducted a 16-item survey exploring how methodologists and clinicians would react when presented with multiple Summary of Findings (SoF) tables (generated using the GRADE tool) derived from 4 overlapping and discordant SRs and meta-analyses on thrombolytic therapy for intermediate-risk pulmonary embolism. SoF tables reported 4 different magnitudes of effects and overall certainty. Participants were asked to provide their recommendations regarding the intervention and the reasons behind their conclusion.

Results

Of the 80 invitees, 41 (51%) participated. The majority described themselves as "somewhat familiar" or experts with SoF tables. The majority recommended the therapy (pharmacological systemic thrombolysis), grading the recommendation as weak positive. Certainty of evidence and benefit-risk balance were the two criteria that prevailed in generating the recommendation. When faced with overlapping meta-analyses, the preferred approach was to use only high-quality SRs and exclude redundant SRs. Several participants suggested integrating the SoF tables with additional information, such as a more comprehensive evaluation of the risk of bias of systematic reviews (71%), heterogeneity/inconsistency (68%) and studies included within each SR (62%).

Conclusion

When faced with multiple controversial SR results, the type and completeness of reported information in SoF tables affect experts' ability to make recommendations. Developers of the SoF table should consider collating key information from overlapping and potentially discordant reviews.

Aggressive Therapy for Acute Pulmonary Embolism: Systemic Thrombolysis and Catheter-Directed Approaches

Venous thromboembolism (VTE) is the third most common cause of cardiovascular disease after myocardial infarction and stroke. Population-based studies estimate that up to 94,000 new cases of pulmonary embolism (PE) occur in the United States annually with an increasing incidence with age. Mortality from PE is the greatest in the first 24 hours, with a decreased survival extending out 3 months. Thus, acute PE is a potentially fatal illness if not recognized and treated in a timely manner. Contemporary management includes systemic anticoagulation, thrombolysis, catheter-based procedures, and surgical embolectomy. This article reviews current clinical evidence and societal guidelines for the use of systemic and catheter-directed thrombolysis for treatment of acute PE.

Fibrinolytics for the treatment of pulmonary embolism

The use of fibrinolytic agents in acute pulmonary embolism (PE), first described over 50 years ago, hastens the resolution of RV stain, leading to earlier hemodynamic improvement. However, this benefit comes at the increased risk of bleeding. The strongest indication for fibrinolysis is in high-risk PE, or that characterized by sustained hypotension, while its use in patients with intermediate-risk PE remains controversial. Fibrinolysis is generally not recommended for routine use in intermediate-risk PE, although most guidelines advise that it may be considered in patients with signs of acute decompensation and an overall low bleeding risk. The efficacy of fibrinolysis often varies significantly between patients, which may be at least partially explained by several factors found to promote resistance to fibrinolysis. Ultimately, treatment decisions should carefully weigh the risks and benefits of the individual clinical scenario at hand, including the overall severity, the patient's bleeding risk, and the presence of factors known to promote resistance to fibrinolysis. This review aims to further explore the use of fibrinolytic agents in the treatment of PE including specific indications, outcomes, and special considerations.

American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism

BACKGROUND

Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), occurs in ∼1 to 2 individuals per 1000 each year, corresponding to ∼300 000 to 600 000 events in the United States annually.

OBJECTIVE

These evidence-based guidelines from the American Society of Hematology (ASH) intend to support patients, clinicians, and others in decisions about treatment of VTE.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and adult patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 28 recommendations for the initial management of VTE, primary treatment, secondary prevention, and treatment of recurrent VTE events.

CONCLUSIONS

Strong recommendations include the use of thrombolytic therapy for patients with PE and hemodynamic compromise, use of an international normalized ratio (INR) range of 2.0 to 3.0 over a lower INR range for patients with VTE who use a vitamin K antagonist (VKA) for secondary prevention, and use of indefinite anticoagulation for patients with recurrent unprovoked VTE. Conditional recommendations include the preference for home treatment over hospital-based treatment for uncomplicated DVT and PE at low risk for complications and a preference for direct oral anticoagulants over VKA for primary treatment of VTE.

Clinical efficacy of low dose recombinant tissue-type plasminogen activator for the treatment of acute intermediate-risk pulmonary embolism

OBJECTIVES

To investigate the efficacy and safety of initial thrombolysis by recombinant tissue-type plasminogen activator (rt-PA) in compared with anticoagulant therapy in patients with acute intermediate-risk pulmonary embolism (PE).  Methods: Sixty-six patients with acute intermediate-risk PE were randomly assigned to receive rt-PA or LMWH between June 2014 and June 2017 in our department. We obtained information regarding the difference in the right ventricle/left ventricle (RV/LV) ratio, pulmonary artery systolic pressure (PASP), clinical symptoms improvement, PE-related mortality, hemodynamic decompensation, recurrent PE, and major and minor bleeding.  Results: In the rt-PA group, the mean PASP was reduced from 52.0±12.2 at baseline to 34.8±9.4 (p less than 0.001) and the mean RV/LV ratio was reduced from 1.26±0.22 at baseline to 0.96±0.18 (p less than 0.001) at 24 hours. In the LMWH group, the mean PASP was 53.4±12.8 at baseline and 48.5±11.9 at 24 hours (p=0.11), and the mean RV/LV ratio was 1.22±0.19 at baseline and 1.17±0.21 at 24 hours (p=0.31). In comparison with the LMWH group, there was a significant reduction in PASP and an improvement in the symptom severity in the rt-PA group. At 90 days, there was no difference in mortality, recurrent venous thromboembolism and major bleeding as a safety outcome, but increased minor bleeding and decreased hemodynamic decompensation occurred in the rt-PA group. Conclusions: In patients with acute intermediate-risk PE, low dose thrombolytic therapy is considered safe and effective, it can be recommended as an alternative option in clinical treatment.