Treatment of acute pulmonary embolism using rheolytic thrombectomy

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.

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.

Is it Time to Reappraise for Black-Box Warning on AngioJet Rheolytic Thrombectomy in Patients with Pulmonary Embolism: A Systematic Review and Meta-analysis

BACKGROUND

AngioJet rheolytic thrombectomy (ART) system has been widely used as a catheter-directed treatment (CDT) method in acute pulmonary embolism (PE), however, there has been a controversy regarding the safety of its use. In this systematic review and meta-analysis, we evaluated the efficacy and safety outcomes of ART in patients with PE.

METHODS

Our meta-analysis have been based on search in the MEDLINE, EMBASE, and Cochrane Library for studies published up to August 2022. The primary outcomes were overall pooled rates of major bleeding (MB) and minor bleeding (mB), worsening renal function (WRF), bradycardia/conduction disturbance (BCD), and PE-related and all-cause mortality in patients who underwent ART.

RESULTS

Among the 233 studies documented at initial search, 24 studies were eligible for meta-analysis, and a total of 427 PE patients who underwent ART were evaluated. Overall pooled rates of MB and mB were 9.6% (95% CI 5.9%-15.2%) and 9.2% (95% CI 6.1%-13.6%), transient BCD and WRF were 18.2% (95% CI 12.4%-26%) and 15% (95% CI 10%-21.8%), and PE-related death and all-cause death were 12.7% (95% CI 9.1%-17.3%) and 15% (95% CI 11%-20%), respectively. However, significant heterogeneity and some evidence of funnel plot asymmetry and publication bias were noted for MB, BCD and WRF, but not for PE-related death and all-cause death.

CONCLUSION

Overall pooled rates of bleeding events, BCD and WRF episodes, PE-related death and all-cause death may be considered as encouraging results for efficacy and safety issues of ART utilization in specific scenarios of acute PE, and a reappraisal for black-box warning on ART seems to be necessary.

Percutaneous Management of High-Risk Pulmonary Embolism

Acute pulmonary embolism (PE) leads to an abrupt increase in pulmonary vascular resistance and right ventricular afterload, and when significant enough, can result in hemodynamic instability. High-risk PE is a dire cardiovascular emergency and portends a poor prognosis. Traditional therapeutic options to rapidly reduce thrombus burden like systemic thrombolysis and surgical pulmonary endarterectomy have limitations, both with regards to appropriate candidates and efficacy, and have limited data demonstrating their benefit in high-risk PE. There are growing percutaneous treatment options for acute PE that include both localized thrombolysis and mechanical embolectomy. Data for such therapies with high-risk PE are currently limited. However, given the limitations, there is an opportunity to improve outcomes, with percutaneous treatments options offering new mechanisms for clot reduction with a possible improved safety profile compared with systemic thrombolysis. Additionally, mechanical circulatory support options allow for complementary treatment for patients with persistent instability, allowing for a bridge to more definitive treatment options. As more data develop, a shift toward a percutaneous approach with mechanical circulatory support may become a preferred option for the management of high-risk PE at tertiary care centers.

Pulmonary Embolism Risk Assessment Using Blood Copeptin Concentration and Pulmonary Arteries Thrombotic Burden Evaluated by Computer Tomography

(1) Background: Pulmonary embolism (PE) represents the third most important cardiovascular cause of death after myocardial infarction and stroke. The proper management of this condition is dependent on adequate risk stratification, due to the life-threatening complications of more aggressive therapies such as thrombolysis. Copeptin is a surrogate marker of vasopressin which is found increased in several cardiovascular conditions. The Mastora score is an imagistic evaluation of the degree of pulmonary arteries thrombotic burden based on computed tomography angiography. In this study, we aimed to evaluate the diagnostic and prognostic role of copeptin in patients with acute PE. Furthermore, we analyzed the relationship between copeptin and Mastora score and their role in PE risk profiling. (2) Methods: We conducted a single center prospective study that included 112 patients with PE and 53 healthy volunteers. Clinical and paraclinical parameters, together with plasma levels of copeptin and the Mastora score, were evaluated in all patients after admission. (3) Results: Copeptin levels were significantly increased in PE patients compared with the general population (26.05 vs. 9.5 pmol/L, p < 0.001), while receiver operating characteristic (ROC) analysis revealed an AUC of 0.800 (95% CI 0.728−0.873, p < 0.001). Copeptin directly correlated with the Mastora score (r = 0.535, p = 0.011) and both parameters were strong predictors for adverse clinical events and death. Receiver operating characteristic (ROC) analysis for death within 30 days revealed a copeptin cut-off of 38.36 pmol/L, which presented a specificity of 79.6% and a sensitivity of 88.9%, and a Mastora score cut-off of 82 points, which presented a specificity of 74.8% and a sensitivity of 77.8%. (4) Conclusions: Our results showed that copeptin and the Mastora score are both correlated with adverse cardiovascular events and mortality in PE patients, and this may pave the way for their use in clinical practice, helping physicians to select the best therapeutical management.

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.

Dilemmas in the Choice of Adequate Therapeutic Treatment in Patients with Acute Pulmonary Embolism—From Modern Recommendations to Clinical Application

Pulmonary thromboembolism is a very common cardiovascular disease, with a high mortality rate. Despite the clear guidelines, this disease still represents a great challenge both in diagnosis and treatment. The heterogeneous clinical picture, often without pathognomonic signs and symptoms, represents a huge differential diagnostic problem even for experienced doctors. The decisions surrounding this therapeutic regimen also represent a major dilemma in the group of patients who are hemodynamically stable at initial presentation and have signs of right ventricular (RV) dysfunction proven by echocardiography and positive biomarker values (pulmonary embolism of intermediate–high risk). Studies have shown conflicting results about the benefit of using fibrinolytic therapy in this group of patients until hemodynamic decompensation, due to the risk of major bleeding. The latest recommendations give preference to new oral anticoagulants (NOACs) compared to vitamin K antagonists (VKA), except for certain categories of patients (patients with antiphospholipid syndrome, mechanical valves, pregnancy). When using oral anticoagulant therapy, special attention should be paid to drug–drug interactions, which can lead to many complications, even to the death of the patient. Special population groups such as pregnant women, obese patients, patients with antiphospholipid syndrome and the incidence of cancer represent a great therapeutic challenge in the application of anticoagulant therapy. In these patients, not only must the effectiveness of the drugs be taken into account, but great attention must be paid to their safety and possible side effects, which is why a multidisciplinary approach is emphasized in order to provide the best therapeutic option.

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.

Extracorporeal Membrane Oxygenation—First Strategy for Acute Life-Threatening Pulmonary Embolism

Background

Both venoarterial extracorporeal membrane oxygenation (VA-ECMO) and percutaneous mechanical thrombectomy (PMT) are increasingly used to treat acute life-threatening pulmonary embolism (PE). However, there are little data regarding their effectiveness. This study aimed to present the short-term outcomes after managing nine patients with acute life-threatening massive or submassive PE by VA-ECMO with or without complemented PMT and propose a preliminary treatment algorithm.

Methods

This study was a single-center retrospective review of a prospectively maintained registry. It included nine consecutive patients with massive or submassive pulmonary embolism who underwent VA-ECMO for initial hemodynamic stabilization, with or without PMT, from August 2018 to November 2021.

Results

Mean patient age was 54.7 years. Four of nine patients (44.4%) required cardiopulmonary resuscitation before or during VA-ECMO cannulation. All cannulations (100%) were successfully performed percutaneously. Overall survival was 88.9% (8 of 9 patients). One patient died from a hemorrhagic stroke. Of the survivors, the median ECMO duration was 8 days in patients treated with ECMO alone and 4 days in those treated with EMCO and PMT. Five of nine patients (55.6%) required concomitant PMT to address persistent right heart dysfunction, with the remaining survivors (44.4%) receiving VA-ECMO and anticoagulation alone. For survivors receiving VA-ECMO plus PMT, median hospital lengths of stay were 7 and 13 days, respectively.

Conclusions

An ECMO-first strategy complemented with PMT can be performed effectively and safely for acute life-threatening massive or submassive PE. VA-ECMO is feasible for initial stabilization, serving as a bridge to therapy primarily in inoperable patients with massive PE. Further evaluation in a larger cohort of patients is warranted to assess whether VA-ECMO plus PMT may offer an alternative or complementary therapy to thrombolysis or surgical thrombectomy.

Type of Research

Single-center retrospective review of a prospectively maintained registry.

Pulmonary Embolism and Pregnancy-Challenges in Diagnostic and Therapeutic Decisions in High-Risk Patients

Diagnosis of acute PE in pregnant women with haemodynamic instability is following the general integrated risk-adapted diagnostic algorithm and starts with bedside echocardiography to assess RV function. If RV dysfunction is identified, a prompt and immediate reperfusion without further imaging should be initiated. Although pregnancy is listed as a relative contraindication of systemic thrombolysis, in pregnant women with acute PE and haemodynamic instability thrombolysis must be considered. In those cases, other treatment strategies as surgical embolectomy or catheter-directed low-dose thromboylysis or percutaneous thrombectomy should be taken into consideration as well. A multidisciplinary team with experience of PE management in pregnancy should be consulted to reach consensus on the best treatment approach.

cRGD Urokinase Liposomes for Thrombolysis in Rat Model of Acute Pulmonary Microthromboembolism

Purpose

To study the thrombolytic effect and safety of cRGD urokinase liposomes (cRGD-UK-LIP) in rats with acute pulmonary microthromboembolism (APMTE), and explore the application value of echocardiography (ECHO) in animal models.

Patients and Methods

Ninety-six SD rats were randomized into 6 groups (16/group): normal control, sham operation, APMTE, normal saline (NS), free urokinase (UK), cRGD-UK-LIP. Four groups (APMTE, NS, UK, cRGD-UK-LIP) of rats were injected with autologous thrombus to induce APMTE. Samples were injected into 3 groups (NS, UK, cRGD-UK-LIP) of rats after modeling. Echocardiography was used to assess right ventricle (RV) function and morphology in rats. Six rats in each group were randomly selected and pulmonary artery pressure (PAP) of them was measured through ECHO-guided transthoracic puncture. Finally, the rats were killed and their tissues were taken for pathological examination.

Results

Compared with normal control or sham operation group, rats in APMTE group had enlarged RV, decreased RV function, increased PAP, and lung tissue of them showed postthromboembolic appearance. There was no significant difference between NS group and APMTE group. RV morphology and function of rats in the UK group and cRGD-UK-LIP group were better and vessels with residual thrombus in these 2 groups were less than APMTE group, especially in the cRGD-UK-LIP group. In terms of PAP, only cRGD-UK-LIP group was significantly lower than APMTE group. No hyperemia, bleeding and swelling were observed in heart, liver and kidney of rats in each group.

Conclusion

A rat model of APMTE was successfully established. cRGD-UK-LIP has better thrombolytic effect than free urokinase and it is safe. Echocardiography is not merely an important way to evaluate the morphology and function of RV, transthoracic puncture measurement under the guidance of it can be an effective way to monitor PAP in animal models.

Pharmacological and interventional management of pulmonary embolism: where do we stand?

As the third most common cardiovascular disease, pulmonary embolism (PE) has an uptrending incidence and mortality, resulting in significant healthcare expenditure. Risk stratification of acute PE guides management. Although anticoagulation remains the cornerstone management, systemic fibrinolysis and targeted therapeutic approaches, catheter-directed thrombolysis and catheter-based embolectomy are available for high-risk patients. Life-threatening bleeding complications associated with systemic fibrinolysis have restricted its widespread implementation. Catheter-based techniques for intermediate high-risk categories were devised to reduce bleeding complications and improve outcomes. Catheter-directed thrombolysis helps minimize bleeding by way of direct drug delivery. Catheter-based embolectomy mechanically retrieves thrombi without using fibrinolytics. This focused review of medical and interventional management of acute PE provides a highlight of ongoing trials expected to add value to current practice.

Percutaneous Mechanical Thrombectomy of Submassive Pulmonary Embolism and Extensive Deep Venous Thrombosis for Early Thrombus Removal

Traditional treatment with anticoagulation in nonfatal submassive pulmonary embolism can result in serious sequelae of chronic thromboembolic pulmonary hypertension or poor exercise tolerance, and functional impairment. To prevent long-term complications in previously healthy young patients, other treatment options to actively resolve existing thrombi should be considered. Despite recommendations for use in only severe clinical presentations, endovascular interventional techniques could serve as suitable treatment options for such patients. Here we report the case of a previously healthy 23-year-old female with submassive pulmonary embolism and extensive deep vein thrombosis in the inferior vena cava down to the right popliteal vein. The patient was initially treated with catheter-directed thrombolysis. However, she continued to show extensive venous thrombosis and pulmonary embolism. Percutaneous thrombectomy and aspiration using an AngioJet successfully removed the main pulmonary artery embolism and venous thrombus. The patient's recovery was uneventful, and 3-month follow-up showed no signs of recurrence or discomfort.

A seven-year single-center experience on AngioJet rheolytic thrombectomy in patients with pulmonary embolism at high risk and intermediate-high risk

BACKGROUND AND AIM

Angiojet Rheolytic thrombectomy (ART) has been utilized as a catheter-based treatment in acute pulmonary embolism (PE). In this study based on our seven-year experience on ART in patients with PE, we evaluated efficacy and safety outcomes of ART.

METHODS

Our study is based on retrospective evaluation of 56 patients with high- and intermediate-high-risk PE, age (62 years; interquartile-range (IQR): 50-73) who underwent ART.

RESULTS

High- and intermediate-high-risk were noted in 21.4 % and in 78.6 % of patients, respectively. ART duration was 304(IQR: 246-468) seconds. Measures of obstruction, right to left ventricle diameter ratio (RV/LV ratio), right to left atrial diameter ratio and pulmonary arterial pressures were improved (p<0.001 for all). During hospital stay, acute renal failure, major and minor bleeding, and mortality rates were 37.5%, 7.1%, 12.5%, and 8.9%, respectively. Aging related to post-procedural nephropathy while high-risk status was associated with in-hospital mortality (p=0.006) and long-term mortality.

CONCLUSIONS

The ART resulted in significant and clinically relevant improvements in the pulmonary arterial thrombotic burden, RV strain and hemodynamics in patients with PE at high- and intermediate-high-risk. Aging increased the risk of post-procedural nephropathy whereas baseline high-risk status predicted in-hospital and long-term mortality.

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.