A meta-analysis of outcomes of catheter-directed thrombolysis for high- and intermediate-risk pulmonary embolism

Novel Challenges and Therapeutic Options for Pulmonary Embolism and Deep Vein Thrombosis

Acute pulmonary embolism (PE), often resulting from deep vein thrombosis (DVT), is the third most frequent cause of cardiovascular death and is associated with increasing incidence, causing considerable morbidity and mortality. This review aims to evaluate the efficacy, safety, and outcomes of treatment options in the management of acute PE and DVT, encompassing both established and emerging technologies, such as catheter-directed thrombolysis, aspiration thrombectomy, and other endovascular techniques. A comprehensive literature review was conducted, assessing clinical studies, trials, and case reports that detail the use of percutaneous interventions for PE and DVT and analyzing the advantages and disadvantages of each percutaneous system. Several percutaneous treatments have shown promising results, especially in cases where rapid thrombus resolution is critical, such as in high- and intermediate-high-risk patients. The incidence of major complications, such as bleeding, remains a consideration, though it is generally manageable with proper patient selection and technique. It is fundamentally important to tailor the specific treatment strategy to the clinical and anatomical characteristics of each patient. Percutaneous treatments for acute PE and DVT represent valuable options in the therapeutic arsenal, offering enhanced outcomes in appropriately selected patients. Ongoing advancements in technology and technique, along with comprehensive clinical trials, are essential to further define the role and optimize the use of these interventions.

Technical Aspects of Penumbra Indigo Lightning Flash System for Mechanical Thrombectomy of Pulmonary Embolism: A Comprehensive Review

PURPOSE

To demonstrate the technical aspects of the novel Penumbra Indigo Lightning Flash System (Penumbra, Inc.) for mechanical thrombectomy of pulmonary embolism (PE).

TECHNIQUE

The novel Penumbra Lightning Flash catheter is a 16 French (F) sheath-compatible device designed for advanced thrombectomy, especially in the pulmonary arteries. This device has large thrombus burden removal capacity; however, technical nuances are necessary to accomplish more with efficacy pulmonary embolism management. Access sites, pulmonary arteries catheterization technique, thrombectomy device navigation and mechanism of action are described thoroughly.

CONCLUSION

Penumbra Indigo Lightning Flash system for mechanical thrombectomy as other catheter-directed treatments (CDTs) represents a major advance in contemporary PE management. With favorable safety profile and efficacy, CDTs have become an integral component of the multidisciplinary approach to PE care.

CLINICAL IMPACT

The article highlights the Penumbra Indigo Lightning Flash System as a significant advancement in mechanical thrombectomy for pulmonary embolism (PE). By detailing technical aspects and procedural nuances, it supports clinicians for improvement in endovascular PE management. The system's integration into multidisciplinary care represents a major step forward, providing an effective alternative to traditional therapies, particularly for high-risk PE patients. This innovation promises to enhance patient outcomes in contemporary PE management.

The Current Evidence of Pulmonary Embolism Response Teams and Their Role in Future

Acute pulmonary embolism (PE) remains a critical medical condition requiring prompt and accurate management. The introduction and growing significance of pulmonary embolism response teams (PERT), also termed EXPERT-PE teams, signify a paradigm shift toward a collaborative, multidisciplinary approach in managing this complex entity. As the understanding of acute PE continues to evolve, PERTs stand as a linkage of optimized care, offering personalized and evidence-based management strategies for patients afflicted by this life-threatening condition. The evolving role of PERTs globally is evident in their increasing integration into the standard care pathways for acute PE. These teams have demonstrated benefits such as reducing time to diagnosis and treatment initiation, optimizing resource utilization, and improving patient outcomes.

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.

Percutaneous interventions for pulmonary embolism

Pulmonary embolism (PE) ranks as a leading cause of in-hospital mortality and the third most common cause of cardiovascular death. The spectrum of PE manifestations varies widely, making it difficult to determine the best treatment approach for specific patients. Conventional treatment options include anticoagulation, thrombolysis, or surgery, but emerging percutaneous interventional procedures are being investigated for their potential benefits in heterogeneous PE populations. These novel interventional techniques encompass catheter-directed thrombolysis, mechanical thrombectomy, and hybrid approaches combining different mechanisms. Furthermore, inferior vena cava filters are also available as an option for PE prevention. Such interventions may offer faster improvements in right ventricular function, as well as in pulmonary and systemic haemodynamics, in individual patients. Moreover, percutaneous treatment may be a valid alternative to traditional therapies in high bleeding risk patients and could potentially reduce the burden of mortality related to major bleeds, such as that of haemorrhagic strokes. Nevertheless, the safety and efficacy of these techniques compared to conservative therapies have not been conclusively established. This review offers a comprehensive evaluation of the current evidence for percutaneous interventions in PE and provides guidance for selecting appropriate patients and treatments. It serves as a valuable resource for future researchers and clinicians seeking to advance this field. Additionally, we explore future perspectives, proposing "percutaneous primary pulmonary intervention" as a potential paradigm shift in the field.

Case Report: Thrombus aspiration and in situ thrombolysis via a Guidezilla guide extension catheter in a patient with high-risk pulmonary embolism

Standard catheter-directed thrombolysis (CDT) and thrombus aspiration are considered potentially promising approaches for reopening the embolism-related pulmonary artery in patients with pulmonary embolism (PE) with high thrombotic burden and deteriorating hemodynamics, especially in those for whom systemic thrombolysis is contraindicated or has failed. However, the constrained accessibility of dedicated catheters has impeded the potential benefits of standard CDT in developing countries. The Guidezilla guide extension catheter (GEC) with a larger diameter and extended length is widely used in challenging coronary anatomy. Nevertheless, there have been few reports on the application of the Guidezilla GEC as a novel option for patients with massive PE when dedicated catheters and surgical thrombectomy are not available. In this case report, we demonstrated that thrombus aspiration and in situ thrombolysis through the Guidezilla GEC are applicable to patients with PE in whom systemic thrombolysis is contraindicated, resulting in successful reperfusion and positive clinical outcomes.

Pulmonary embolism and hemorrhage after displacement of angiographic catheter tip to pulmonary artery: A case report and literature review

Pulmonary embolism and massive hemoptysis caused by intravascular foreign bodies have rarely been reported. We report a case of an end-stage renal disease patient in which the tip of the angiographic catheter fell off into the pulmonary artery during endovascular interventional opening when the patient underwent vascular access occlusion for dialysis. During the operation, the foreign body was displaced repeatedly and finally anchored to the posterior basal segment branch of the right lower pulmonary artery. A pulmonary embolism occurred during the operation, and massive hemoptysis and hemorrhagic shock occurred after anticoagulation and thrombolytic therapy. After receiving anti-shock and symptomatic treatment, the patient gradually recovered. After six months of follow-up, no pulmonary embolism or pulmonary infarction occurred. Our case report presents an alternative approach to extracting a foreign object from the pulmonary artery by locating the foreign object within the vascular terminations, without resorting to forceful removal. This method mitigates the potential risks of pulmonary embolism and bleeding associated with forceful extraction.

Underuse of reperfusion therapy with systemic thrombolysis in high-risk acute pulmonary embolism in a Portuguese center

INTRODUCTION

Reperfusion therapy is generally recommended in acute high-risk pulmonary embolism (HR-PE), but several population-based studies report that it is underused. Data on epidemiology, management and outcomes of HR-PE in Portugal are scarce.

OBJECTIVE

To determine the reperfusion rate in HR-PE patients, the reasons for non-reperfusion, and how it influences outcomes.

METHODS

In this retrospective cohort study of consecutive HR-PE patients admitted to a thromboembolic disease referral center between 2008 and 2018, independent predictors for non-reperfusion were assessed by multivariate logistic regression. PE-related mortality and long-term MACE (cardiovascular mortality, PE recurrence and chronic thromboembolic disease) were calculated according to the Kaplan-Meier method. Differences stratified by reperfusion were assessed using the log-rank test.

RESULTS

Of 1955 acute PE patients, 3.8% presented with hemodynamic instability. The overall reperfusion rate was 50%: 35 patients underwent systemic thrombolysis, one received first-line percutaneous embolectomy and one rescue endovascular treatment. Independent predictors of non-reperfusion were: age, with >75 years representing 12 times the risk of non-treatment (OR 11.9, 95% CI 2.7-52.3, p=0.001); absolute contraindication for thrombolysis (31.1%), with recent major surgery and central nervous system disease as the most common reasons (OR 16.7, 95% CI 3.2-87.0, p<0.001); and being hospitalized (OR 7.7, 95% CI 1.4-42.9, p=0.020). At a mean follow-up of 2.5±3.3 years, the survival rate was 33.8%. Although not reaching statistical significance for hospital mortality, mortality in the reperfusion group was significantly lower at 30 days, 12 months and during follow-up (relative risk reduction of death of 64% at 12 months, p=0.013). Similar results were found for MACE.

CONCLUSIONS

In this population, the recommended reperfusion therapy was performed in only 50% of patients, with advanced age and absolute contraindications to fibrinolysis being the main predictors of non-reperfusion. In this study, thrombolysis underuse was associated with a significant increase in short- and long-term mortality and events.

Sonothrombolysis: State-of-the-Art and Potential Applications in Children

In recent years, advances in ultrasound therapeutics have been implemented into treatment algorithms for the adult population; however, the use of therapeutic ultrasound in the pediatric population still needs to be further elucidated. In order to better characterize the utilization and practicality of sonothrombolysis in the juvenile population, the authors conducted a literature review of current pediatric research in therapeutic ultrasound. The PubMed database was used to search for all clinical and preclinical studies detailing the use and applications of sonothrombolysis, with a focus on the pediatric population. As illustrated by various review articles, case studies, and original research, sonothrombolysis demonstrates efficacy and safety in clot dissolution in vitro and in animal studies, particularly when combined with microbubbles, with potential applications in conditions such as deep venous thrombosis, peripheral vascular disease, ischemic stroke, myocardial infarction, and pulmonary embolism. Although there is limited literature on the use of therapeutic ultrasound in children, mainly due to the lower prevalence of thrombotic events, sonothrombolysis shows potential as a noninvasive thrombolytic treatment. However, more pediatric sonothrombolysis research needs to be conducted to quantify the safety and ethical considerations specific to this vulnerable population.

Effect of a pulmonary embolism response team on the management and outcomes of patients with acute pulmonary embolism

OBJECTIVE

We aimed to evaluate the effects of a multidisciplinary pulmonary embolism (PE) response team (PERT) on the management and outcomes of patients with acute PE.

METHODS

We retrospectively reviewed all patients presenting to our institution with a diagnosis of PE from July 2020 to April 2022. The primary outcome measures were in-hospital mortality, major bleeding events defined by the International Society on Thrombosis and Haemostasis, and use of catheter-directed interventions (CDIs). The secondary outcome measures included 30-day and 12-month mortality, hospital and intensive care unit (ICU) lengths of stay, vasopressor requirement, and cardiac arrest. Continuous variables were assessed using the Mann-Whitney U test and categorical variables using the χ2 or Fisher exact test, as appropriate.

RESULTS

A total of 279 patients with acute PE were identified, of whom 79 (28%), 173 (62%), and 27 (10%) were considered to have low risk, intermediate risk, and high risk, respectively. The PERT was activated for 133 patients (47.7%). Saddle and main pulmonary artery embolisms (P < .001), right ventricular strain (P= .001), right ventricular dysfunction (P < .001), coexisting deep vein thrombosis (P < .001), and dyspnea as a presenting symptom (P = .008) were significantly associated with PERT activation. Patients evaluated by the PERT were more likely to undergo CDI (49% vs 27%; P < .001) across all risk groups and less likely to have an inferior vena cava filter placed (1% vs 5%; P = .04). PERT consultation showed numerical, but nonstatistically significant, trends toward reduced in-hospital (2% vs 5%; P = .2) and 30-day (2% vs 8%; P = .06) mortality but similar rates of 12-month mortality (7% vs 8%; P = .7). PERT activation was also associated with a trend toward reduced rates of major bleeding (2% vs 7%), cardiac arrest (2% vs 7%), and vasopressor requirement (9% vs 18%). PERT consultations decreased the median number of ICU days by one half; however, we did not observe any differences in the total hospital length of stay between the groups.

CONCLUSIONS

At our institution, PERT consultations were associated with significantly higher usage of CDIs and improved clinical outcomes, including reduced mortality and a lower rate of major bleeding events. PERT consultations were also associated with fewer ICU days, suggesting a possible economic benefit for implementing PERTs, although further research is needed to confirm that conclusion.

A comparison of the efficacy and safety between anticoagulation alone and combined with catheter-directed thrombolysis for treatment of pulmonary embolism on outcome: A systematic review and meta-analysis

BACKGROUND

Catheter-directed thrombolysis (CDT) is one of the newest treatment options for submassive pulmonary embolism (sPE). This study will compare the efficacy and safety of catheter-directed thrombolysis (CDT) combine with anticoagulation versus anticoagulation alone (AC) in patients with PE.

METHODS

A database search was conducted using PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov for trials that compared CDT with AC in patients with pulmonary embolism. The primary outcomes was1-year mortality. The secondary outcomes were in-hospital, 30 days, 90 days mortality, in-hospital major and minor bleeding (Thrombolysis in Myocardial Infarction (TIMI) classification), length of hospital stay (LOS), reduction of pulmonary arterial systolic pressure (PASP) and RV/LV diameter ratio.

RESULTS

A total of 16 articles (3 RCTs and 13 non-RCTs) and 10595 patients were included in this study. 2237 patients were in the CDT group and 8358 patients were in the AC group. CDT group was associated with significantly lower in-hospital mortality (2.1% vs 6.2%,OR:0.36, 95%CI:0.26-0.51, p < .00001,I2 = 0%), 30 days mortality (3.1% vs 8.6%,OR:0.39,95%CI:0.23-0.66, p = .0005, I2 = 0%), 90 days mortality (3.8% vs 7.7%,OR:0.49,95%CI:0.29-0.80,p = .005,I2 = 7%), 1-year mortality (6.1% vs 11%, OR:0.51, 95%CI:0.35-0.76, p = .0008,I2 = 36%) compared to AC group, especially in ultrasound-assisted thrombolysis (USAT) subgroup. There were no differences on major bleeding between two groups (1.8% vs 2.2%, OR:1.10, 95%CI:0.61-1.98, p = .75, I2 = 0%). Minor bleeding was significantly higher in CDT group than AC group (6.2% vs 3.8%, OR:1.93,95%CI:1.27-2.94.66, p = .002, I2 = 1%). CDT group significantly reduced PASP (WMD:11.90,95%CI:6.45-17.35, p < .0001, I2 = 72%) and RV/LV (WMD:0.17,95%CI:0.04-0.30, p = .009, I2 = 69%) rapidly than AC group after treatment. LOS was similar between two groups (WMD:0.02,95%CI: -0.68-0.73, p = .95, I2 = 51%).

CONCLUSION

Results thus confirmed that CDT reduced in-hospital, 30 days, 90 days and 1-year all-cause mortality in patients with sPE compared to AC, particularly in USAT subgroup. Nonetheless, CDT group was associated with a higher risk of minor bleeding.

Comparison of therapeutic effect of catheter direct thrombolysis and peripheral venous thrombolysis on acute pulmonary embolism

We compared the therapeutic effect of catheter direct thrombolysis (CDT) and peripheral venous thrombolysis (PVT) for patients with acute pulmonary embolism (APE). Totally, 74 patients with APE were enrolled, including 37 in the CDT group and 37 in the PVT group. The changes in clinical indicators pre and posttreatment were observed. Clinical efficacy was evaluated. Kaplan-Meier method was used to analyze the survival of patients during follow-up. In both the PVT group and CDT group, partial pressure of oxygen after treatment increased significantly than that before treatment (P < .05). However, in both groups, the levels of partial pressure of carbon dioxide, D-dimer, B-type brain natriuretic peptide, pulmonary arterial pressure, and thrombus volume after treatment were significantly decreased than those before treatment (P < .05). After treatment, patients from the CDT group had significantly lower D-dimers, partial pressure of carbon dioxide, brain natriuretic peptide, and pulmonary arterial pressure, and significantly higher partial pressure of oxygen compared to patients from the PVT group (P < .05). The total effective rate was 97.2% in the CDT group and 81.0% in the PVT group. The bleeding incidence in the CDT group was significantly lower than that in the PVT group (P < .05). The median survival time in the CDT group was significantly longer than that in the PVT group (P < .05). CDT can more effectively improve symptoms, cardiac function, and survival rate of APE patients while reducing bleeding incidence than PVT, and thus is safe and effective in treating APE.

Factors associated with bleeding after ultrasound-assisted catheter-directed thrombolysis for the treatment of pulmonary embolism

Ultrasound-assisted catheter directed thrombolysis (US-CDT) is frequently used for the treatment of pulmonary embolism. Due to the variety of thrombolytic and anticoagulant dosing utilized in practice, patients with pulmonary embolism who undergo US-CDT may be at an increased risk of bleeding. The primary objective of this study was to determine factors associated with major bleeding occurring with US-CDT. Secondary outcomes included in-hospital mortality and ventilator-free days. This multicentre retrospective cohort study evaluated inpatients diagnosed with pulmonary embolism and treated with US-CDT and systemic anticoagulation. A total of 173 patients were included. Most patients receiving US-CDT had a submassive pulmonary embolism with a median Pulmonary Embolism Severity Index (PESI) score of 85. Major bleeding events occurred in 37 of the 173 patients (21%). In-hospital mortality occurred in four (11%) of the patients who experienced major bleeding and three (2%) patients who did not experience major bleeding (P = 0.04). Factors associated with a higher risk of major bleeding included female sex and anticoagulation strategy. The odds of major bleeding were 3.3 times higher for women than for men (odds ratio = 3.32, 95% confidence interval 1.29-8.54). In addition, for each second increase in goal aPTT the odds of major bleeding increased by 5% (odds ratio = 1.05, 95% confidence interval 1.02-1.09). In patients with pulmonary embolism treated with US-CDT, major bleeding may be underestimated. In this analysis, major bleeding was associated with female sex and higher goal aPTT levels. In addition, bleeding with US-CDT was associated with a higher risk of in-hospital mortality.

Mechanical thrombectomy versus catheter directed thrombolysis in patients with pulmonary embolism: A multicenter experience

OBJECTIVES

Compare in-hospital outcomes of patients treated with either mechanical thrombectomy (MT) or catheter directed lysis (CDL) in treatment of acute pulmonary embolism (PE).

METHODS

This is a multicenter, retrospective cohort study of patients undergoing MT or CDL for acute PE between 2014 and 2021. The primary outcome was the composite of in-hospital death, significant bleed, vascular complication, or need for mechanical support post-procedure. Secondary outcomes included the individual components of the composite outcome in addition to blood transfusions, invasive hemodynamics, echocardiographic data, and intensive care unit (ICU) utilization.

RESULTS

458 patients were treated for PE with 266 patients in the CDL arm and 192 patients in the MT arm. The primary composite endpoint was not significantly different between the two groups with CDL 12% versus MT 11% (p = 0.5). There was a significant difference in total length of ICU time required with more in the CDL group versus MT (3.8 ± 2.0 vs. 2.8 ± 3.0 days, p = 0.009). All other secondary end points showed no significant difference between the groups.

CONCLUSIONS

In patients undergoing catheter directed treatment of PE, there was no difference between MT and CDL in terms of in-hospital mortality, bleeds, catheter-related complications, and hemodynamics.

Systemic thrombolytic and ultrasound-assisted catheter-directed thrombolysis for treatment of acute pulmonary embolism: a 7-year, multicenter experience

Treatment of acute pulmonary embolism (PE) varies based upon risk stratification and ranges from outpatient oral anticoagulation to emergency surgical embolectomy. Patients with high-risk PE can be considered for systemic thrombolytic (ST) based upon guideline recommendations, but intermediate-risk PE does not currently have strong evidence to guide primary reperfusion strategies via thrombolytic administration. Ultrasound-assisted catheter-directed thrombolysis (USAT) is an alternative reperfusion option to ST but is not currently recommended as first line in any key guidelines due to limited available evidence. This retrospective, multicenter, observational study compares 210 patients treated with USAT (n = 105) or ST (n = 105) for acute high- or intermediate-risk PE in three hospitals. Baseline characteristics were significant in that severity of illness was higher in those that received ST, which limited comparisons of outcomes. The primary outcome of major bleeding in patients receiving USAT was 15.2% and 22.9% in those that received ST. Efficacy of reperfusion strategy was observed to be 86.7% of patients in USAT group and 65.7% in ST group. Reperfusion strategies had no difference in in-hospital death, intensive care length of stay, or hospital length of stay. Predefined subgroup analysis found that high-risk PE had higher mortality (14.7%) than intermediate-risk PE (0%) regardless of reperfusion strategy. Upon multivariate analysis, high-risk PE was the only independent risk factor for major bleeding while USAT therapy and intermediate-risk PE were independent predictors of efficacy. Due to the difference in baseline severity of illness, direct comparisons in primary outcomes to each group was not performed. We have described real world usage of both USAT and ST and which patients were likely to receive each therapy at these institutions.

Percutaneous treatment options for acute pulmonary embolism: a clinical consensus statement by the ESC Working Group on Pulmonary Circulation and Right Ventricular Function and the European Association of Percutaneous Cardiovascular Interventions

There is a growing clinical and scientific interest in catheter-directed therapy (CDT) of acute pulmonary embolism (PE). Currently, CDT should be considered for patients with high-risk PE, in whom thrombolysis is contraindicated or has failed. Also, CDT is a treatment option for initially stable patients in whom anticoagulant treatment fails, i.e., those who experience haemodynamic deterioration despite adequately dosed anticoagulation. However, the definition of treatment failure (primary reperfusion therapy or anticoagulation alone) remains an important area of uncertainty. Moreover, several techniques for CDT are available without evidence supporting one over the other, and variation in practice with regard to periprocedural anticoagulation is considerable. The aim of this position paper is to describe the currently available CDT approaches in PE patients and to standardise patient selection, the timing and technique of the procedure itself as well as anticoagulation regimens during CDT. We discuss several clinical scenarios of the clinical evaluation of the "efficacy" of thrombolysis and anticoagulation, including treatment failure with haemodynamic deterioration and treatment failure based on a lack of improvement. This clinical consensus statement serves as a practical guide for CDT, complementary to the formal guidelines.

Clinical efficacy and safety of ultrasound-assisted thrombolysis vs. standard catheter-directed thrombolysis in patients with acute pulmonary embolism: A study level meta-analysis of clinical trials

Aim

To compare the clinical efficacy of ultrasound-assisted thrombolysis (USAT) vs. standard catheter-directed thrombolysis (SCDT) in patients with acute pulmonary embolism (aPE).

Methods

This study analyzed the clinical outcomes of patients with non-low-risk aPE who received USAT or SCDT. The primary outcomes were all-cause death, total bleeding, and major bleeding. Secondary outcomes included pulmonary thrombotic load score (Miller), improvement in right ventricular-to-left ventricular ratio (RV/LV), dose and duration of the thrombolytic drug tissue plasminogen activator (tPA), length of stay (LOS) in the ICU, and total LOS in the hospital.

Results

A total of seven articles and 451 patients were included in this study. 241 patients were in the USAT group and 210 patients were in the SCDT group. There were no significant differences in all-cause mortality, total bleeding, and major bleeding between the two groups. Miller scores for pulmonary thrombus also showed no difference between the two groups, but pulmonary artery systolic pressure (PASP) was lower in the SCDT group after-treatment. The reduction of RV/LV from baseline was more pronounced in the SCDT group than in the USAT group (OR: -0.14, 95%CI: -0.20 to 0.07, P < 0.0001, I ² = 0%). Total dose of tPA and duration of infusion in the USAT group were lower than those in the SCDT group, but there was no significant statistical difference. LOS in the ICU was similar between the two groups, while LOS in the hospital was lower in the SCDT group.

Conclusion

This study did not detect any differences in all-cause mortality, total bleeding, and major bleeding between non-low-risk aPE patients treated with USAT or SCDT. Improvement in right ventricular function was better in the SCDT group, and hospital LOS was lower in the SCDT group.

Treatment With EkoSonic™ Endovascular System (EKOS®) of Massive Pulmonary Thrombosis Following Recovery From COVID-19 Infection

COVID-19 infection caused by the new coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an infection with symptoms and results ranging from mild flu-like symptoms to severe respiratory failure leading to death. The risk of thrombosis increases due to hypercoagulation in COVID-19 infection. All causes (endothelial injury, stasis, and hypercoagulopathy) known as Virchow's triad contribute to thrombosis in COVID-19 infection. However, the pathogenesis of hypercoagulability in COVID-19 is still unknown. In this article, we discuss the unique multiple thrombosis events following recovery from COVID-19 infection and our treatment strategy for pulmonary thrombosis. The patient had symptoms of dry cough, fever, and myalgia two months ago. His polymerase chain reaction (PCR) test for COVID-19 was positive, but there was no need for hospitalization. His symptoms resolved within seven days. But, thrombosis of the superior mesenteric artery (SMA) occurred one month after the COVID-19 infection, and bowel resection was performed. He was admitted to our hospital with dyspnea, chest pain, palpitations, and hoarseness. Further evaluation showed tachycardia, hypotension, tachypnea, and anxiety. Peripheral oxygen saturation (SpO₂) was 86% at room air. He had hemodynamic instability, right ventricular (RV) dysfunction, and D-Dimer elevation. Pulmonary Embolism Severity Index (PESI) was calculated as 149. The patient was in the high-risk group. Our Pulmonary Embolism Response Team (PERT) decided to apply catheter-directed thrombolysis (CDT) for the treatment of pulmonary thrombosis. The EkoSonic™ Endovascular System (EKOS) (Boston Scientific Corporation, Marlborough, USA) was used for the treatment.

Advances in Percutaneous Management of Pulmonary Embolism

Acute pulmonary embolism (PE) is a leading cause of morbidity and mortality worldwide. Systemic anticoagulation remains the recommended treatment for low-risk PE. Systemic thrombolysis is the recommended treatment for PE with hemodynamic compromise (massive/high-risk PE). A significant number of patients are not candidates for systemic thrombolysis due to the bleeding risk associated with thrombolytics. Historically, surgical pulmonary embolectomy (SPE) was recommended for massive PE with hemodynamic compromise for these patients. In the last decade, catheter-directed thrombolysis (CDT) has largely replaced SPE in the patient population with intermediate risk PE (submassive), defined as right heart strain (as evidenced by right ventricle enlargement on echocardiogram and/or computed tomography, usually along with elevation of troponin or B-type natriuretic peptide). Use of CDT increased in the last few years due to high incidence of PE in hospitalized patients with coronavirus disease 2019 pneumonia, and the use of mechanical thrombectomy (initially reserved for those with contraindications to thrombolysis) has also grown. In this article, we discuss the value of the PE response team, our approach to management of submassive (intermediate risk) and massive (high risk) PE with systemic thrombolytics, CDT, mechanical thrombectomy, and surgical embolectomy.

Massive Embolism: Knife versus PCI

Pulmonary embolism is the third most common cardiovascular syndrome with an estimated up to 25% of patients presenting with sudden death. For those who survive, a mainstay of management for patients with hemodynamic stability is anticoagulation; however, recommendations and options are rapidly changing for patients with submassive or massive pulmonary embolism with hemodynamic instability. Catheter-based and surgical approaches offer efficacious management options for unstable patients or patients with contraindications to anticoagulation; however, both approaches have inherent benefits and risk. This article seeks to offer a brief review on the recommendations and options for management of pulmonary embolism from both surgical and catheter-based perspectives.

Catheter-Based Therapies Decrease Mortality in Patients With Intermediate and High-Risk Pulmonary Embolism: Evidence From Meta-Analysis of 65,589 Patients

Background

Catheter-directed therapies (CDT) are an alternative to systemic thrombolysis (ST) in pulmonary embolism (PE) patients, but the mortality benefit of CDT is unclear.

Objective

We conducted a systematic review with meta-analysis to compare the efficacy and safety of CDT and ST in intermediate-high and high-risk PE.

Methods

We included (P) participants, adult PE patients; (I) intervention, CDT; (C) comparison, ST; (O) outcomes, mortality, complications, in-hospital treatment, and length of hospital stay; (S) study design, randomized controlled trials (RCTs), or cohort comparing CDT and ST. The primary endpoint was 30-day mortality. Secondary outcomes included treatment-related complications including bleeding, the use of hospital resources, and length of hospital stay.

Results

Eleven studies including 65,589 patients met the inclusion criteria. Thirty-day mortality was lower in the CDT group, compared to ST group [7.3 vs. 13.6%; odds ratio (OR) = 0.51, 95% confidence interval (CI) 0.38–0.69, p < 0.001]. The rates of myocardial injury, cardiac arrest, and stroke were lower in CDT group, compared to ST group (p < 0.001 for all). The rates of any major bleeding, intracranial hemorrhage, hemoptysis, and red blood cell transfusion were lower in patients treated with CDT, compared to ST (p ≤ 0.01 for all). Extracorporeal life support was used more often in patients treated with CDT, compared to ST (0.5 vs. 0.2%, OR = 2.52, 95% CI 1.88–3.39, p < 0.001). The use of hospital resources and length of hospital stay were comparable in both groups.

Conclusion

CDT might decrease mortality in patients with intermediate-high and high-risk PE and were associated with fewer complications, including major bleeding.

Acute Management of High-Risk and Intermediate-Risk Pulmonary Embolism in Children: A Review

Severe forms of pulmonary embolism (PE) in children, althought rare, cause significant morbidity and mortality. We review the pathophysiologic features of severe (high-risk and intermediate-risk) PE and suggest novel pediatric-specific risk stratifications and an acute treatment algorithm to expedite emergent decision-making. We defined pediatric high-risk PE as causing cardiopulmonary arrest, sustained hypotension, or normotension with signs or symptoms of shock. Rapid primary reperfusion should be pursued with either surgical embolectomy or systemic thrombolysis in conjunction with a heparin infusion and supportive care as appropriate. We defined pediatric intermediate-risk PE as a lack of systemic hypotension or compensated shock, but with evidence of right ventricular strain by imaging, myocardial necrosis by elevated cardiac troponin levels, or both. The decision to pursue primary reperfusion in this group is complex and should be reserved for patients with more severe disease; anticoagulation alone also may be appropriate in these patients. If primary reperfusion is pursued, catheter-based therapies may be beneficial. Acute management of severe PE in children may include systemic thrombolysis, surgical embolectomy, catheter-based therapies, or anticoagulation alone and may depend on patient and institutional factors. Pediatric emergency and intensive care physicians should be familiar with the risks and benefits of each therapy to expedite care. PE response teams also may have added benefit in streamlining care during these critical events.

Management of Submassive Bilateral Pulmonary Embolism in an Adolescent Female

Pulmonary embolism (PE) is a rare presentation in the pediatric population. We report a case of submassive PE in an adolescent female following commencement of a combined oral contraceptive pill (COCP). In the setting of cardiac dysfunction, she received systemic thrombolysis with significant reduction of clot burden and clinical improvement objectively demonstrated shortly thereafter. This case highlights challenges in clinical decision-making regarding surgical or catheter-based interventions versus medical management approaches when addressing life-threatening PE in children. Our case demonstrates that submassive PE in pediatrics can be managed successfully with systemic thrombolysis and therapeutic anticoagulation.

Nineteen-Year Trends in Mortality of Patients Hospitalized in the United States with High-Risk Pulmonary Embolism

BACKGROUND

Several advanced treatments of high-risk patients with pulmonary embolism have been used in recent decades. We assessed the 19-year national trend in mortality of high-risk patients with pulmonary embolism to determine what impact, if any, advanced therapy might have had on mortality.

METHODS

Mortality (case fatality rate) was assessed in patients with a primary (first-listed) diagnosis of high-risk pulmonary embolism who were hospitalized during the period from 1999 to 2014 and in 2016 and 2017. High-risk was defined as patients with pulmonary embolism who were in shock or suffered cardiac arrest. International Classification of Diseases, 9th revision, Clinical Modification codes were used for data on the period from 1999 to 2014, and version 10 codes were used for data on the years 2016 and 2017. Trends in mortality were assessed according to treatment.

RESULTS

From 1999 to 2017 (excluding 2015), 58,784 patients were hospitalized in United States with a primary diagnosis of pulmonary embolism that was high risk. Mortality in all high-risk patients decreased from 72.7% in 1999 to 49.8% in 2017 (P < .0001). Most high-risk patients (60.3%) were treated with anticoagulants alone and did not receive an inferior vena cava filter. Mortality in these patients decreased from 79.0% in 1999 to 55.7% in 2017 (P < .0001). Thrombolytic therapy was administered to 16.1% of high-risk patients, open pulmonary embolectomy alone was used in 4.3%, and extracorporeal membrane oxygenation was used in 0.4%.

CONCLUSIONS

Mortality of high-risk patients with pulmonary embolism has decreased. This decrease can be attributed to improved treatment of patients with shock and with cardiac arrest, and does not reflect advances in therapy for pulmonary embolism.

The safety and efficacy of systemic versus catheter-based therapies: application of a prognostic model by a pulmonary embolism response team

The decision by pulmonary embolism response teams (PERTs) to utilize anticoagulation (AC) with or without systemic thrombolysis (ST) or catheter-directed therapies (CDT) for pulmonary embolism (PE) is a balance between the desire for a positive outcome and safety. Our primary aim was to develop a predictive model of in-hospital mortality for patients with high- or intermediate-risk PE managed by PERT while externally validating this model. Our secondary aim was to compare the relative safety and efficacy of ST and CDT in this cohort. Consecutive patients hospitalized between June 2014 and January 2020 at the Cleveland Clinic Foundation and The University of Rochester with acute high- or intermediate-risk PE managed by PERT were retrospectively evaluated. Groups were stratified by treatment strategy. The primary outcome was in-hospital mortality, and secondary outcome was major bleeding. A logistic regression model to predict the primary outcome was built using the derivation cohort, with 100-fold bootstrapping for internal validation. External validation was performed and the area under the receiver operating curve (AUC) was calculated. Of 549 included patients, 421 received AC alone, 71 received ST, and 64 received CDT. Predictors of major bleeding include ESC risk category, PESI score, hypoxia, hemodynamic instability, and serum lactate. CDT trended towards lower mortality but with an increased risk of bleeding relative to ST (OR = 0.42; 95% CI [0.15, 1.17] and OR = 2.14; 95% CI [0.9, 5.06] respectively). In the multivariable logistic regression model in the derivation institution cohort, predictors of in-hospital mortality were age, cancer, hemodynamic instability requiring vasopressors, and elevated NT-proBNP (AUC = 0.86). This model was validated using the validation institution cohort (AUC = 0.88). We report an externally-validated model for predicting in-hospital mortality in patients with PE managed by PERT. The decision by PERT to initiate CDT or ST for these patients had no impact on mortality or major bleeding, yet the long-term efficacy of these interventions needs to be elucidated.

Catheter-directed therapy in pulmonary embolism

Acute pulmonary embolism (PE) is a life-threatening condition with high mortality rates and potential long-term sequelae. Systemic thrombolysis has been virtually the only therapeutic option available for patients with hemodynamic instability over decades. Recently, interventional therapy of PE has gained increasing interest. Multiple devices were developed; these include devices for local thrombolysis, thrombus fragmentation, thrombus aspiration, and combined approaches. However, the available evidence is limited to mostly small, nonrandomized studies. In these studies, safety and efficacy data from patients with intermediate or high-risk PE are promising. However, due to the lack of adequately powered randomized trials, interventional treatment of intermediate or high-risk PE cannot be recommended as standard-of-care. The decision on whether and how to perform a catheter-based intervention should therefore be left to the discretion of the local team, depending on the patients' clinical status, bleeding risk, local expertise, and available devices. The implementation of local multidisciplinary PE response teams is recommended by international guidelines to provide the best possible treatment.

Interventional Reperfusion Strategies for Acute Pulmonary Embolism

Acute pulmonary embolism (APE) is a common, potentially life-threatening cardiovascular emergency, and represents the third leading cause of cardiovascular mortality after myocardial infarction and stroke. Risk stratification is important to guide the management of APE, as an early reperfusion strategy is associated with improved clinical outcomes in specific high-risk conditions. Pulmonary artery reperfusion is commonly achieved by systemic intravenous administration of thrombolytic drugs, but catheter-directed thrombolysis (CDThr) and interventional techniques of catheter-based embolectomy provide novel therapeutic approaches with an improved risk-benefit ratio. Future trials will help to determine when to use these different devices in massive or sub-massive APE, and which patient population is likely to benefit from interventional treatment.

Predictors of residual pulmonary vascular obstruction after anticoagulation monotherapy in patients with intermediate-risk pulmonary embolism

Background

Patients with intermediate-risk pulmonary embolism (PE) can be treated with anticoagulation monotherapy. However, clinicians are concerned as to whether anticoagulation monotherapy is sufficient to reduce mortality in patients with a large embolic burden, and to resolve vascular obstruction. We investigated whether anticoagulation monotherapy was appropriate in patients with intermediate risk PE in terms of the occurrence of residual pulmonary vascular obstruction (RPVO), and the factors that independently predict the occurrence of RPVO.

Methods

This was a multicenter retrospective observational study of patients at intermediate risk of PE who were admitted to three hospitals between January 2012 and December 2017.

Results

Of total 91 patients, the median age was 72 years and 37 (40.7%) were male. Twenty-five patients (27.5%) were diagnosed with RPVO during follow-up. Multivariate logistic regression revealed chronic lung disease [odds ratio (OR), 4.14; 95% confidence interval (CI), 1.243–13.797; P=0.021] and the ratio of the diameters of the main pulmonary artery and ascending aorta ratio (P/A ratio) >1.0 documented on a chest computed tomography (CT) at presentation (OR, 3.46; 95% CI, 1.113–10.770; P=0.032) were significant independent predictors of RPVO occurrence. The incidence of RPVO in patients without these two factors was only 9.7%, but in those with the two factors it was 60% (P=0.004).

Conclusions

Anticoagulation monotherapy did not seem to be a sufficient treatment to reduce RPVO, but the outcome was similar to that of patients treated with other therapies. Therefore, considering the risk-benefit ratio, we do not need to change the initial treatment as systemic thrombolytic therapy or catheter-based therapy in patient with intermediate risk PE. Underlying chronic lung disease and a P/A ratio >1 on the initial chest CT predicted the occurrence of RPVO. Therefore, we should carefully assess persistent of dyspnea and exercise limitations using various methods in patients with these risk factors, to detect the occurrence of chronic thromboembolic pulmonary disease (CTEPD) earlier.

Randomized Trial Comparing Standard Versus Ultrasound-Assisted Thrombolysis for Submassive Pulmonary Embolism: The SUNSET sPE Trial

OBJECTIVES

The aim of this trial was to determine whether ultrasound-assisted thrombolysis (USAT) is superior to standard catheter-directed thrombolysis (SCDT) in pulmonary arterial thrombus reduction for patients with submassive pulmonary embolism (sPE).

BACKGROUND

Catheter-directed therapy has been increasingly used in sPE and massive pulmonary embolism as a decompensation prevention and potentially lifesaving procedure. It is unproved whether USAT is superior to SCDT using traditional multiple-side-hole catheters in the treatment of patients with pulmonary embolism.

METHODS

Adults with sPE were enrolled. Participants were randomized 1:1 to USAT or SCDT. The primary outcome was 48-hour clearance of pulmonary thrombus assessed by pre- and postprocedural computed tomographic angiography using a refined Miller score. Secondary outcomes included improvement in right ventricular-to-left ventricular ratio, intensive care unit and hospital stay, bleeding, and adverse events up to 90 days.

RESULTS

Eighty-one patients with acute sPE were randomized and were available for analysis. The mean total dose of alteplase for USAT was 19 ± 7 mg and for SCDT was 18 ± 7 mg (P = 0.53), infused over 14 ± 6 and 14 ± 5 hours, respectively (P = 0.99). In the USAT group, the mean raw pulmonary arterial thrombus score was reduced from 31 ± 4 at baseline to 22 ± 7 (P < 0.001). In the SCDT group, the score was reduced from 33 ± 4 to 23 ± 7 (P < 0.001). There was no significant difference in mean thrombus score reduction between the 2 groups (P = 0.76). The mean reduction in right ventricular/left ventricular ratio from baseline (1.54 ± 0.30 for USAT, 1.69 ± 0.44 for SCDT) to 48 hours was 0.37 ± 0.34 in the USAT group and 0.59 ± 0.42 in the SCDT group (P = 0.01). Major bleeding (1 stroke and 1 vaginal bleed requiring transfusion) occurred in 2 patients, both in the USAT group.

CONCLUSIONS

In the SUNSET sPE (Standard vs. Ultrasound-Assisted Catheter Thrombolysis for Submassive Pulmonary Embolism) trial, patients undergoing USAT had similar pulmonary arterial thrombus reduction compared with those undergoing SCDT, using comparable mean lytic doses and durations of lysis.

A Case of Failure of EkoSonic™ Endovascular System in the Treatment of Submassive Pulmonary Embolism

Submassive pulmonary embolism (SPE) is characterized by the presence of right ventricular (RV) strain as visualized on echocardiogram or CT scan with brain natriuretic peptide (BNP) and/or troponin elevation. The condition accounts for 20-25% of all pulmonary embolism (PE) cases. In cases of SPE, catheter-directed thrombolysis (CDT) is generally considered in the presence of severe hypoxemia, worsening RV dysfunction, patients with increasing tachycardia and elevated troponins, free-floating thrombus in the right atrium or RV, and presence of extensive clot burden. EkoSonic™ Endovascular System (EKOS; Boston Scientific, Marlborough, MA) has been successfully used to treat cases of PE even where systemic thrombolytic therapy has failed. However, in this article, we describe a unique case of the failure of EKOS in treating a 71-year-old African American man who presented to the hospital with progressively worsening chest pain, shortness of breath, and fatigue. He was suspected to have SPE; however, a CT pulmonary angiogram could not be performed to estimate the clot burden due to an acute kidney injury. He was diagnosed with coronavirus disease 2019 (COVID-19) pneumonia during the hospitalization and had a delayed EKOS procedure with minimal improvement in oxygenation and clot burden. He subsequently underwent half-dose systemic thrombolytic therapy with complete resolution of his symptoms. Given our success with half-dose systemic therapy, we propose that it may be considered as a "rescue therapy" in cases where EKOS fails to deliver results.

Pragmatic Use of Catheter-Directed Thrombolysis in Venous Thromboembolism and a Comparative Evaluation With Traditional Therapies in Submassive Pulmonary Embolism

BACKGROUND

Catheter-directed thrombolysis (CDT) is a novel treatment for venous thromboembolism (VTE). Limited data describe pragmatic use of CDT and compare CDT to other VTE therapies.

OBJECTIVE

Assess the use of CDT and comparatively evaluate CDT, anticoagulation, and systemic thrombolysis in submassive pulmonary embolism (PE).

METHODS

Retrospective, single-center, chart audit. Part 1 described all patients who received CDT for VTE. Part 2 matched patients with submassive PE who received CDT, heparin, or systemic thrombolysis and assessed length of stay (LOS), bleeding, all cause in-hospital mortality, and escalation of care.

RESULTS

For part 1, 70 CDT patients were identified; 42 with DVT and 28 with PE. ICU LOS was longer (2.5 ± 2.9 vs. 4.9 ± 8.4 days, p = 0.07), escalation of care more frequent (0% vs. 35.7%, p < 0.0001), and hospital mortality greater (2.4% vs. 21.4%, p = 0.014) in the PE group. For part 2, 21 CDT patients were matched to 21 heparin and 21 systemic thrombolysis patients. All CDT and tPA patients were admitted to the ICU versus only 6 (28.6%, p < 0.001) heparin patients. ICU LOS was significantly longer in the CDT group versus systemic tPA and systemic anticoagulation (80.7 ± 64.1 vs. 48.2 ± 27.7 vs. 24.9 ± 59.1 hours; p = 0.0048). More IVC filters and thrombectomies were performed in the CDT group.

CONCLUSIONS

CDT is frequently used for both DVT and PE and requires ICU admission. Escalation of care is common when CDT is used for PE. For submassive PE, CDT is associated with prolonged ICU LOS compared to heparin or systemic thrombolysis. Resource utilization with CDT requires further evaluation.

Outcomes of catheter-directed interventions in high-risk pulmonary embolism-a retrospective analysis

BACKGROUND

First-line treatment of high-risk pulmonary embolism with persistent hypotension and/or signs of shock is intravenous thrombolysis. However, if thrombolysis is contraindicated due to risk of serious bleeding, or if it yields insufficient effect, surgical thrombectomy or catheter-directed intervention (CDI) plus anticoagulation is recommended. The aim of this study was to assess the outcomes of the CDI modality introduced in a tertiary referral centre in 2013.

METHODS

Retrospective comparison between patients treated with CDI plus anticoagulation (n = 22) and patients treated with anticoagulation only (n = 23) as used before the CDI technique was available. The main outcomes of interest were 90-day survival and reduction of right to left ventricle diameter (RV/LV) ratio, using the Fischer's exact test and a mixed model, respectively, for statistical analysis.

RESULTS

Ninety-day survival was 59% after CDI and 61% after anticoagulation only; P = .903. The rate of RV/LV ratio reduction was 0.4 units higher per 24 hours in the CDI group (median 2.1 pre-treatment), than in the anticoagulation only group (median 1.3 pre-treatment); P = .007.

CONCLUSION

In patients with high-risk pulmonary embolism, 90-day survival was similar after treatment with CDI plus anticoagulation compared to anticoagulation only. The mean reduction in RV/LV ratio was larger in the CDI group. Our results support the use of CDI in selected patients, respecting the limitations and potential side effects of each technical device used.

Clinical outcomes of very elderly patients treated with ultrasound-assisted catheter-directed thrombolysis for pulmonary embolism: a systematic review

Pulmonary embolism (PE) is a significant cause of death in the very elderly (≥ 75 years) population. Ultrasound-assisted catheter-directed thrombolysis (USCDT) emerges to improve thrombolysis safety and efficacy. However, outcomes in very elderly patients are unknown, as randomized controlled trials exclude this population. Recently, we demonstrated acute kidney injury (AKI) and ischemic hepatitis in an octogenarian intermediate-risk PE patient treated with USCDT. Considering the lack of evidence, we undertook a systematic review to evaluate the clinical outcomes in very elderly PE patients treated with USCDT. We searched for very elderly PE patients treated with USCDT from 2008 to 2019. Additionally, we conducted another systematic review without age restriction to update previous evidence and compare both populations. We also did an exploratory analysis to determine if thrombolysis was followed based on current guidelines or impending clinical deterioration factors. We identified 18 very elderly patients (age 79.2, 75-86), mostly female and with intermediate-risk PE. We found an intracranial hemorrhage (ICH), and a right pulmonary artery rupture. Additionally, two significant bleedings complicated with transient AKI, and one case of AKI and ischemic hepatic injury. The patients who survived all had clinical and echocardiographic in-hospital improvement. Despite low rt-PA doses, ICH and major bleeding remain as feared complications. Thrombolysis decision was driven by impending clinical deterioration factors instead of international guideline recommendations. Our data do not suggest prohibitive risk associated with USCDT in very elderly intermediate and high-risk PE patients. Despite long-term infusions and right ventricular dysfunction, AKI and ischemic hepatic injury were infrequent.

Catheter-Directed Therapy: Outcomes Versus Standard of Care and Evaluation of Current Practice

BACKGROUND

Small studies have noted benefit with the use of catheter-directed therapy (CDT) versus standard of care in treatment of pulmonary embolism, but none have focused on the variability of clinical practice with this modality.

METHODS

International Classification of Diseases (ICD) codes were used to retrospectively identify consecutive adult patients admitted to an intensive care unit (ICU) with pulmonary embolism over a 2-year period. We evaluated inpatient mortality and major bleeding and assessed treatment variation.

RESULTS

Of 284 patients included, 46 underwent CDT (9 massive pulmonary embolism, 37 submassive pulmonary embolism). Significantly more patients who underwent standard treatment had a history of congestive heart failure and diabetes. Obesity, higher troponin levels, and right heart strain were significantly more likely in the CDT group. No significant difference in inpatient mortality or major bleeding events was observed between the treatment groups. Tissue plasminogen activator use varied widely in the CDT group, and inferior vena cava filter utilization was significantly more common in the CDT group (18; 41%) compared with the standard group (40; 17%) (P < 0.01).

CONCLUSIONS

In this study, no significant difference in inpatient mortality or major bleeding was found in patients in the intensive care unit with pulmonary embolism who underwent CDT compared with standard care. It may be beneficial to standardize this procedure given the potential benefit of CDT in patients with submassive pulmonary embolism.

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.

Current Endovascular Treatment Options in Acute Pulmonary Embolism

Acute pulmonary embolism (PE) is a significant cause of mortality and morbidity across the globe. Over the last few decades, there have been major therapeutic advances in acute PE management, including catheter-based therapy. However, the effectiveness of catheter-based therapy in acute PE is not supported by Level I evidence, making the use of this promising treatment rather controversial and ambiguous. In this paper, we discuss the risk stratification of acute PE and review the medical and endovascular treatment options. We also summarize and review the data supporting the use of endovascular treatment options in acute PE and describe the potential role of the PE response team.

Thrombolytic therapy in acute venous thromboembolism

Although anticoagulation remains the mainstay of treatment of acute venous thromboembolism (VTE), the use of thrombolytic agents or thrombectomy is required to immediately restore blood flow to thrombosed vessels. Nevertheless, systemic thrombolysis has not clearly been shown to improve outcomes in patients with large clot burdens in the lung or legs as compared with anticoagulation alone; this is in part due to the occurrence of intracranial hemorrhage in a small percentage of patients to whom therapeutic doses of a thrombolytic drug are administered. Algorithms have been developed to identify patients at high risk for poor outcomes resulting from large clot burdens and at low risk for major bleeding in an effort to improve outcomes in those receiving thrombolytic therapy. In acute pulmonary embolism (PE), hemodynamic instability is the key determinant of short-term survival and should prompt consideration of immediate thrombolysis. In hemodynamically stable PE, systemic thrombolysis is not recommended and should be used as rescue therapy if clinical deterioration occurs. Evidence is accumulating regarding the efficacy of administering reduced doses of thrombolytic agents systemically or via catheters directly into thrombi in an effort to lower bleed rates. In acute deep venous thrombosis, catheter-directed thrombolysis with thrombectomy can be used in severe or limb-threatening thrombosis but has not been shown to prevent postthrombotic syndrome. Because the management of acute VTE can be complex, having a rapid-response team (ie, PE response team) composed of physicians from different specialties may aid in the management of severely affected patients.

Pulmonary embolism: update on management and controversies

Pulmonary embolism is a common and potentially fatal cardiovascular disorder that must be promptly diagnosed and treated. The diagnosis, risk assessment, and management of pulmonary embolism have evolved with a better understanding of efficient use of diagnostic and therapeutic options. The use of either clinical probability adjusted or age adjusted D-dimer interpretation has led to a reduction in diagnostic imaging to exclude pulmonary embolism. Direct oral anticoagulation therapies are safe, effective, and convenient treatments for most patients with acute venous thromboembolism, with a lower risk of bleeding than vitamin K antagonists. These oral therapeutic options have opened up opportunities for safe outpatient management of pulmonary embolism in selected patients. Recent clinical trials exploring the use of systemic thrombolysis in intermediate to high risk pulmonary embolism suggest that this therapy should be reserved for patients with evidence of hemodynamic compromise. The role of low dose systemic or catheter directed thrombolysis in other patient subgroups is uncertain. After a diagnosis of pulmonary embolism, all patients should be assessed for risk of recurrent venous thromboembolism to guide duration of anticoagulation. Patients with a venous thromboembolism associated with a strong, transient, provoking risk factor can safely discontinue anticoagulation after three months of treatment. Patients with an ongoing strong risk factor, such as cancer, or unprovoked events are at increased risk of recurrent events and should be considered for extended treatment. The use of a risk prediction score can help to identify patients with unprovoked venous thromboembolism who can benefit from extended duration therapy. Despite major advances in the management of pulmonary embolism, up to half of patients report chronic functional limitations. Such patients should be screened for chronic thromboembolic pulmonary hypertension, but only a small proportion will have this as the explanation of their symptoms. In the remaining patients, future studies are needed to understand the pathophysiology and explore interventions to improve quality of life.

Adjunctive Therapy and Mortality in Patients With Unstable Pulmonary Embolism

Mortality with adjunctive therapy in patients with unstable pulmonary embolism, defined as those in shock or on ventilator support, is sparsely studied and requires further investigation. This was a retrospective cohort study based on administrative data from the Nationwide Inpatient Sample, 2016. In-hospital all-cause mortality in unstable patients with acute pulmonary embolism was assessed according to treatment. Patients were identified by International Classification of Diseases-10-Clinical Modification Codes. Most unstable patients, 85%, received only anticoagulants. Their mortality was 3,080 of 6,635 (46%) without an inferior vena cava (IVC) filter, and mortality was much less with an IVC filter, 285 of 1,185 (24%) (p <0.0001). Mortality with catheter-directed thrombolysis alone, 70 of 235 (30%), did not differ significantly from mortality with anticoagulants plus an IVC filter, p = 0.07, although a trend favored the latter. Intravenous thrombolytic therapy without an IVC filter showed a mortality of 295 of 695 (42%) which tended to be lower than mortality with anticoagulants alone (p = 0.06). The addition of an IVC filter to intravenous thrombolytic therapy resulted in a mortality of 20 of 165 (12%), which was the lowest mortality with any combination of adjunctive treatments. Intravenous thrombolytic therapy, however, was associated with more adverse effects of therapy than catheter-directed thrombolysis or anticoagulants.

Feasibility of ultrasound-assisted catheter-directed thrombolysis for submassive pulmonary embolism: A meta-analysis of case series

BACKGROUND

During the past few years, there has been a surge in the use of ultrasound-assisted catheter-directed thrombolysis (UACDT) for submassive pulmonary embolism (SPE). However, few studies evaluated the feasibility of UACDT for SPE.

PURPOSE

To evaluate the feasibility of UACDT in treating SPE.

METHODS

A comprehensive search of online databases was performed. Search terms UACDT in SPE were entered into PubMed, Embase, Scopus and the Cochrane Library to identify related articles published until October 2018. A quality assessment and data extraction were performed by two researchers. Meta-analysis was performed using R statistical software.

RESULTS

Twelve studies with 485 patients were included in this meta-analysis. The pooled right ventricular/left ventricular ratio decrease and pulmonary artery systolic pressure drop after treatment was -0.34 (95% CI: -0.43, -0.25) and -15.05 (95% CI: -18.10, -12.00) mm Hg, respectively. The pooled major bleeding rate was 1.0% (95% CI: 0.0%, 3.0%), and the in-hospital mortality was 0.0% (95% CI: 0.0%, 1.0%).

CONCLUSION

This up to data meta-analysis confirms that UACDT is a feasible treatment for SPE.

Local Thrombolysis in High-Risk Pulmonary Embolism-13 Years Single-Center Experience

To evaluate the prognosis after local thrombolysis compared to systemic thrombolysis in high-risk pulmonary embolism. Observational study during 13 years which included 37 patients with high-risk pulmonary embolism treated with local thrombolysis and 36 patients with systemic thrombolysis (streptokinase, 250 000 UI/30 minutes followed by 100 000 UI/h). Cardiogenic shock has totally remitted in the group with local thrombolysis (P = .002). The decrease in pressure gradient between right ventricle and right atrium was comparable in both groups in the acute period (the results being influenced by the higher in-hospital mortality after systemic thrombolysis), but significantly better in the next 24 months follow-up after in situ thrombolysis. Major and minor bleeding did not have significant differences. In hospital, mortality was significantly lower in the group with local thrombolysis (P = .003), but for the next 24 months follow-up, the survival was comparable in both groups. Local thrombolysis, during the hospitalization, was associated with lower mortality rate comparing with systemic thrombolysis. In the next 24 months follow-up, the evolution of residual pulmonary hypertension was significantly better after in situ thrombolysis.

The Role of EkoSonic Endovascular System or EKOS® in Pulmonary Embolism

Pulmonary embolism has become a cause of great concern to health care professionals. Despite strides in research and availability of sensitive diagnostic tests, the mortality and morbidity related to this entity continues to cause tremendous economic burden. Patients present with an array of symptoms ranging from mild dyspnea to hemodynamic instability and even death. Prompt recognition of symptoms along with early risk stratification can be lifesaving. Management focuses on achieving hemodynamic stability and reducing clot burden. Approved treatment modalities include anticoagulation, systemic or catheter directed thrombolytic therapy and surgical embolectomy. In this article we will review catheter-directed thrombolytic therapy, specifically the EKOS® or the EkoSonic endovascular system. EKOS® uses ultrasound-facilitated catheter-directed thrombolysis. The rationale behind this therapy is using shorter infusion times and lower dosage of the thrombolytic therapy, thereby reducing the complications associated with their use.

Immediate and late impact of reperfusion therapies in acute pulmonary embolism

Haemodynamic instability and right ventricular dysfunction are the key determinants of short-term prognosis in patients with acute pulmonary embolism (PE). Residual thrombi and persistent right ventricular dysfunction may contribute to post-PE functional impairment, and influence the risk of developing chronic thromboembolic pulmonary hypertension. Patients with haemodynamic instability at presentation (high-risk PE) require immediate primary reperfusion to relieve the obstruction in the pulmonary circulation and increase the chances of survival. Surgical removal of the thrombi or catheter-directed reperfusion strategies is alternatives in patients with contraindications to systemic thrombolysis. For haemodynamically stable patients with signs of right ventricular overload or dysfunction (intermediate-risk PE), systemic standard-dose thrombolysis is currently not recommended, because the risk of major bleeding associated with the treatment outweighs its benefits. In such cases, thrombolysis should be considered only as a rescue intervention if haemodynamic decompensation develops. Catheter-directed pharmaco-logical and pharmaco-mechanical techniques ensure swift recovery of echocardiographic and haemodynamic parameters and may be characterized by better safety profile than systemic thrombolysis. For survivors of acute PE, little is known on the effects of reperfusion therapies on the risk of chronic functional and haemodynamic impairment. In intermediate-risk PE patients, available data suggest that systemic thrombolysis may have little impact on long-term symptoms and functional limitation, echocardiographic parameters, and occurrence of chronic thromboembolic pulmonary hypertension. Ongoing and future interventional studies will clarify whether ‘safer’ reperfusion strategies may improve early clinical outcomes without increasing the risk of bleeding and contribute to reducing the burden of long-term complications after intermediate-risk PE.