Ultrasound-assisted Catheter-directed Thrombolysis Research Articles

Radiological indicators of chronicity in patients with acute symptomatic pulmonary embolism treated with ultrasound-assisted catheter-directed thrombolysis: a study of 180 consecutive cases

Abstract Background Radiological signs of chronic thrombi are present in up to 20% of patients that present acutely with pulmonary embolism (PE). Ultrasound-Assisted Catheter-Directed Thrombolysis (USAT) can swiftly reverse right ventricular dysfunction in patients with acute PE. Purpose To investigate the frequency of radiological signs of chronic PE and pre-existing chronic thromboembolic pulmonary hypertension in patients treated with USAT and their impact on early and long-term hemodynamic and clinical outcomes. Methods The index CT scans of patients receiving USAT for acute intermediate-high and high-risk PE at a tertiary academic institution (2017-2022) were adjudicated by three expert radiologists blinded for treatment scheme and outcomes. Changes in invasively-measured mean pulmonary artery pressure (mPAP) at 24 hours post USAT, presence of post-PE impairment (PPEI), and CTEPH diagnoses after at least 3 months were studied. A total of 15 radiological signs of chronicity were assessed, including 6 major criteria that have been previously validated to raise the suspicion of pre-existing CTEPH. In this study, acute-on-chronic PE was defined when at least 3 of the 6 validated radiological criteria for chronicity were present together with acute findings. Pre-existing CTEPH was defined based on the results of follow-up (vs. index) CT scan and on the anatomical consistency of pathology specimens after pulmonary endarterectomy. PPEI was defined by the presence of residual respiratory symptoms and right ventricular dysfunction during follow-up. Results Of 180 consecutive patients (median age 65 years, 61% men, 17% high-risk PE), 31 had at least 3 of 6 radiological criteria at the time of acute presentation; Table 1. The median modified Miller Score was 24 points and baseline mPAP was 35 mmHg in both groups. The absolute mPAP reduction after USAT was 11 (Q1-Q3: 5-17) mmHg in patients with <3 and 10 (Q1-Q3: 5, 17) mmHg in those with ≥3 criteria; Table 2. Three (1.7%) patients were diagnosed with CTEPH after a median of 3 months and underwent pulmonary endarterectomy: in all 3 patients, CTEPH was pre-existing. At least 3 of the 6 previously validated criteria were present in all CTEPH patients at index CT. In the 3 patients with acute PE on pre-existing CTEPH, the median baseline mPAP was much higher (median 53 mmHg) than in the remaining patient group and the absolute reduction after USAT was 9 mmHg, corresponding to a relative reduction of 19%. During follow-up, PPEI was more frequent in patients with <3 signs (n=4, 2.7%) than in those with ≥3 signs (n=4, 12.9%). Conclusion(s) The evaluation of six radiological parameters in initial CT scans successfully identified all cases of pre-existing CTEPH in patients presenting with acute PE. However, these parameters did not prove effective in determining which patients would benefit from USAT in terms of mPAP reduction.Baseline characteristicsHemodynamic and clinical outcomes

Routine use of ultrasound-assisted catheter-directed thrombolysis for the management of intermediate-high risk pulmonary embolism: a service evaluation project

Abstract Background Intermediate-high risk Pulmonary Embolism (PE) has considerable morbidity. Conservative management could be sub-optimal. Ultrasound-Assisted Catheter-Directed Thrombolysis (UACDT) is used in our centre for the routine management of this presentation. Purpose We assessed the procedure safety and short-term outcomes by reviewing locally performed procedures. Methods This is an observational retrospective cohort study, with a historic control group. Our centre is a District General Hospital (DGH) in the United Kingdom, and we receive referrals from local acute hospitals. Since the introduction of this service in June 2018 until November 2023, 129 patients (2 patients/month) received routine management with UACDT for intermediate-high risk PE. The controls are 75 acute PE patients of comparable risk classes, managed from January to December 2016. We assessed procedural and in-hospital outcomes including minor, major bleeding/complications and death. We also assessed Length of Stay (LoS) in hospital, recurrent Venous Thrombo-Embolism (VTE) and re-admission rates for recurrent PE at 30 days. Reduction of oxygen requirements and improved estimated systolic Pulmonary Artery Pressure (sPAP) post-procedure were assessed as surrogate measures. Continuous variables were analysed with a Mann-Whitney U test, and categorical variables with a Chi-square Test. Results Baseline demographics are listed in Table 1. Mean duration between CT Pulmonary Angiography (CTPA) and the UACDT procedure was 1.6 (±SD 1.4) days, including inter-hospital transfer. Only 6% (8/129) of UACDT cohort received ≤12 mg standard alteplase dose. In the control group, 4% (3/75) of patients received standard 100mg systemic thrombolysis. There was no significant difference in the rates of minor (p= 0.9), major bleeding/complications (p= 0.8), or death (p= 1.0) between both groups. There was also no significant difference in rates of recurrent VTE (p= 1.0) or re-admission within 30 days for PE (p=0.1) (Table 2). LoS in hospital data were ratified, to exclude inappropriate delays (e.g. physiotherapy requirements, etc). We used the date when the patient was declared medically fit for discharge, and no significant difference was noted (p= 0.2). This was confirmed with a regression analysis of UACDT treatment effect (p= 0.9, CI= -3.5 to 3.1). Nonetheless, there was a 25% reduction of median LoS in hospital from 8 days in the controls to 6 days with UACDT. The proportion of patients requiring O2 was also reduced from 69% (89/129) to 41% (54/129) on day 1 post-procedure. A significant reduction of the estimated sPAP by TTE post-procedure was detected by a mean of 10.4 (±SD 13.9) mmHg (p= <0.01). Conclusion UACDT is generally safe with low complications rate. Compared to the control group, there was a reduction in absolute deaths and median LoS in hospital. This can be secondary to the significant acute reduction of systolic pulmonary artery pressure identified.

Ultrasound-assisted catheter-directed thrombolysis therapy for normotensive shock in acute pulmonary embolism.

Ultrasound-assisted catheter-directed thrombolysis therapy for normotensive shock in acute pulmonary embolism.

Ultrasound-assisted catheter-directed thrombolysis versus surgical pulmonary embolectomy for intermediate-high or high-risk pulmonary embolism: a randomized phase II non-inferiority trial.

We hypothesized that ultrasound-assisted thrombolysis (USAT) is non-inferior to surgical pulmonary embolectomy (SPE) to improve right ventricular (RV) function in patients with acute pulmonary embolism (PE). In a single-centre, non-inferiority trial, we randomly assigned 27 patients with intermediate-high or high-risk acute PE to undergo either USAT or SPE stratified by PE risk. Primary and secondary outcomes were the baseline-to-72-h difference in right-to-left ventricular (RV/LV) ratio and the Qanadli pulmonary occlusion score, respectively, by contrast-enhanced chest-computed tomography assessed by a blinded CoreLab. The trial was prematurely terminated due to slow enrolment. Mean age was 62.6 (SD 12.4) years, 26% were women, and 15% had high-risk PE. Mean change in RV/LV ratio was -0.34 (95% CI -0.50 to -0.18) in the USAT and -0.53 (95% CI -0.68 to -0.38) in the SPE group (mean difference: 0.152; 95% CI 0.032-0.271; Pnon-inferiority = 0.80; Psuperiority = 0.013). Mean change in Qanadli pulmonary occlusion score was -7.23 (95% CI -9.58 to -4.88) in the USAT and -11.36 (95% CI -15.27 to -7.44) in the SPE group (mean difference: 5.00; 95% CI 0.44-9.56, P = 0.032). Clinical and functional outcomes were similar between the 2 groups up to 12 months. In patients with intermediate-high and high-risk acute PE, USAT was not non-inferior when compared with SPE in reducing RV/LV ratio within the first 72 h. In a post hoc superiority analysis, SPE resulted in greater improvement of RV overload and reduction of thrombus burden.

Long-term results after ultrasound-assisted catheter-directed thrombolysis for acute iliofemoral thrombosis

Zusammenfassung Hintergrund und Fragestellung Unter der konservativen Standardbehandlung der proximalen Phlebothrombose (DVT) entwickeln 40–70 % der Patienten ein postthrombotisches Syndrom (PTS). Zur Vermeidung eines PTS kann in Einzelfällen eine chirurgische Thrombektomie oder eine interventionelle Rekanalisierung in Betracht gezogen werden. Ziel unserer Studie war die Untersuchung der Effektivität der frühzeitigen Intervention mittels ultraschallassistierter Katheterthrombolyse (UACDT) mit dem EKOS EndoWave Katheter im Langzeitverlauf. Methodik In einer monozentrischen retrospektiven Studie wurden 42 Patienten (49,9 ± 18,1 Jahre) nachuntersucht, die zwischen Juli 2011 und November 2019 mit einer UACDT bei iliofemoraler Thrombose behandelt wurden. Primäre Endpunkte waren die PTS-Rate gemessen anhand der Villalta-Skala sowie die Erhebung der krankheitsspezifischen Lebensqualität anhand des VEINS-QOL. Ergebnisse Bei 40 Patienten (95,2 %) konnte primär erfolgreich eine Rekanalisierung der Beckenetage bei einer durchschnittlichen Lyse-Dauer von 56,5 (SD ± 17,2) Stunden erreicht werden. Es wurden 22 Patienten (52,4 %) nach einem mittleren Beobachtungszeitraum von 50,4 Monaten (± 30,9) nachuntersucht. Die PTS-Rate lag insgesamt bei 27,3 % (6 Patienten). Das Venensystem zeigte sich in der Duplexsonographie bei 80 % der nachuntersuchten Patienten durchgängig. Schlussfolgerung Die UACDT als frühe thrombusbeseitigende Maßnahme bei proximaler DVT zeigt eine niedrige PTS-Rate im Langzeitverlauf und kann die krankheitsspezifische Lebensqualität dieser Patienten verbessern. Sie ist aber mit einem Risiko der Blutungskomplikation assoziiert, sodass die Indikationsstellung weiterhin kritisch gestellt werden sollte.

Integrating Pharmacomechanical Treatments for Pulmonary Embolism Management within a Hub-and-Spoke System in the Swiss Ticino Region.

The Swiss Ticino regional pulmonary embolism response team (PERT) features direct access to various pharmacomechanical PE management options within a hub/spoke system, by integrating evidence, guidelines' recommendations and personal experiences. This system involves a collaborative management of patients among the hospitals distributed throughout the region, which refer selected intermediate-high or high PE patients to a second-level hub center, located in Lugano at Cardiocentro Ticino, belonging to the Ente Ospedaliero Cantonale (EOC). The hub provides 24/7 catheterization laboratory activation for catheter-based intervention (CBI), surgical embolectomy and/or a mechanical support system such as extracorporeal membrane oxygenation (ECMO). The hub hosts PE patients after percutaneous or surgical intervention in two intensive care units, one specialized in cardiovascular anesthesiology, to be preferred for patients without relevant comorbidities or with hemodynamic instability and one specialized in post-surgical care, to be preferred for PE patients after trauma or surgery or with relevant comorbidities, such as cancer. From April 2022 to December 2023, a total of 65 patients were referred to the hub for CBI, including ultrasound-assisted catheter-directed thrombolysis (USAT) or large-bore aspiration intervention. No patient received ECMO or underwent surgical embolectomy.

Ultrasound-assisted catheter-directed thrombolysis for treatment of deteriorating intermediate-high-risk pulmonary embolism in early pregnancy.

Ultrasound-assisted catheter-directed thrombolysis for treatment of deteriorating intermediate-high-risk pulmonary embolism in early pregnancy.

Ultrasound-Assisted Catheter-Directed Thrombolysis for the Management of Pulmonary Embolism: A Single Center Experience in a Community Hospital.

Current guidelines recommend anticoagulation alone for low-risk pulmonary embolism (PE) with the addition of systemic thrombolysis for high-risk PE. However, treatment recommendations for intermediate-risk PE are not well-defined. Due to bleeding risks associated with systemic thrombolysis, ultrasound-assisted catheter-directed thrombolysis (USAT) has evolved as a promising treatment modality. USAT is thought to decrease the rate of major bleeding by using localized delivery with lower thrombolytic dosages. Currently, there is little guidance on the implementation of USAT in the real-world clinical setting. This study was designed to evaluate our experience with USAT at this single community hospital with a newly initiated Pulmonary Embolism Response Team (PERT). All patients identified by the PERT with an acute PE diagnosed by a computed tomography (CT) scan from January 2021 to January 2023 were included. During the study period, there were 89 PERT activations with 40 patients (1 high-risk and 37 intermediate-risk PE) receiving USAT with alteplase administered at a fixed rate of 1 mg/h per catheter for 6 h. The primary efficacy outcome was the change in Pulmonary Embolism Severity Index (PESI) score within 48 h after USAT. The primary safety outcome was major bleeding within 72 h. The mean age was 57.4 ± 17.4 years and 50% (n = 20) were male, 17.5% (n = 7) had active malignancy, and 20% (n = 8) had a history of prior deep vein thrombosis (DVT) or PE. The mean PESI score decreased from baseline to 48 h post-USAT (84.7 vs 74.9; p = 0.025) and there were no major bleeding events. The overall hospital length of stay was 7.5 ± 9.8 days and ICU length of stay was 2.2 ± 2.8 days. This study outlined our experience at this single community hospital which resulted in an improvement in PESI scores and no major bleeding events observed.

The background and role of catheter-directed thrombolysis evolving procedures for acute iliofemoral deep venous thrombosis.

Minimal invasive treatment such as early endovenous thrombus removal for iliofemoral deep venous thrombosis (DVT) emerged in the end of last century. The principle is catheter-directed thrombolysis (CDT) using either plasminogen activating agents alone, as ultrasound-assisted CDT, or in combination with mechanical devices as pharmaco-mechanical CDT. The interest for this treatment modality is the high rate of post-thrombotic syndrome (PTS) with anticoagulation (AC) alone, especially after iliofemoral DVT. Recently published randomized controlled trials (RCTs) comparing early thrombus removal with AC alone, as well as non-randomized studies, have demonstrated favorable rates, or at least a decrease of moderate and severe PTS, in favor of these procedures. This article will summarize the background and evolution of the procedures in the last three decades and discuss fundamental criteria for inclusion and exclusion, focusing on the procedures regarding thrombus age and location, technical issues, complications and results including different outcome measures for PTS, for which iliac DVT involvement is a massive risk factor to be prevented.

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

BackgroundAcute 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. MethodsWe 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. ResultsIn 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). ConclusionOur 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.

Effectiveness and safety of catheter-directed thrombolysis for acute pulmonary embolism: a systematic review and meta-analysis

Abstract Background Catheter-directed thrombolysis (CDT) can accelerate relief of the right ventricle overload secondary to acute pulmonary embolism (PE). The effectiveness and safety of CDT, also in relation to dose, duration, and different devices, are still a matter of debate. Purpose We conducted a systematic review and meta-analysis to assess effectiveness and safety of CDT for intermediate- and high-risk acute PE. Methods We systematically searched PubMed, Web of Science and CENTRAL (inception-December 2022) and selected randomized controlled trials (RCTs), observational studies, and epidemiological analysis (DRG-based, nationwide studies), focusing on standard CDT (sCDT) vs. ultrasound-assisted catheter-directed thrombolysis (USAT) for intermediate- and high-risk acute PE, according to European Society of Cardiology definition. We obtained pooled estimate rates for bleeding (intracranial and major), in-hospital/30-day fatality rate, and estimated the early improvement of several hemodynamic parameters (i.e. right/left ventricle [RV/LV] ratio, pulmonary artery pressure [PAP]) and long-term course. Results Overall, 58 studies with 37,496 patients (mean age 60 years) were included. The pooled intracranial bleeding rate was 0.15% (95%CI: 0-0.58%) in trials and cohort studies, and 0.87% (95%CI: 0.44-1.42%) in epidemiological studies; Fig. 1. Randomized trials comparing CDT vs. anticoagulation alone reported neither intracranial nor fatal bleeding events. In trials and cohort studies, higher rates of major bleedings were observed with longer (4.5%; 95%CI: 2.4-7.1%) vs. shorter (0.7%, 95%CI: 0-2.2%) treatment duration (p=0.01), irrespective of the dose; Fig. 2. Longer CDT regimens were associated with a high fatality rate of 2.8% (95%CI: 1.5-4.2%) vs. 0.1% (95%CI: 0-1.1%) with shorter CDT treatment (<0.01), disregarding the lytic dose; Fig. 2. All early hemodynamic and radiological outcomes assessed in available studies improve after CDT regardless of dose, duration, and type of device. However, data on the long-term course of PE after CDT has been rarely reported in literature. Conclusions The available evidence supports the notion that CDT strategies may represent a safe option for reversing right ventricular dysfunction due to acute PE. Overall, the reported rate of intracranial bleeding was below 1%. Patients exposed to longer CDT regimens had a higher incidence of major bleeding and fatality. Randomised trials with clinical outcomes are necessary to truly establish optimal patient selection and CDT protocol.Prevalence of intracranial bleedingOutcomes in RCTs and cohort studies

Abstract 13715: Catheter-Based Therapies in High-Risk Pulmonary Embolism: Outcomes From a Tertiary Referral Center

Introduction: Prompt and effective treatment of pulmonary embolism (PE) is essential to prevent morbidity and mortality. We aim to evaluate and compare the effectiveness of two FDA-approved catheter-based therapies (CBT) for acute high-risk PE: ultrasound-assisted catheter-directed thrombolysis EKOS (EKOS Corporation, Bothell, WA) and Penumbra Indigo aspiration thrombectomy (Penumbra Inc., Alameda, CA, USA). Methods: Patients with acute high-risk submassive or massive PE who underwent CBTs between 09/2014 and 08/2022 at our institution were identified. The primary efficacy outcome was the change in the echocardiographic RV/LV diameter ratio within 48 to 72h of procedure. Results: A total of 189 patients underwent EKOS (n=119) or Penumbra (n=70) for submassive (n=175) and massive (n=14) PE (Table). Both groups had similar demographics and clinical characteristics except for prior DVT. Mean age was 60.6±14.3 years old and 55.6% were male. The RV/LV ratio showed significant improvement post intervention, with 21.2% decrease in the EKOS group (EG) and 35.6% in the Penumbra group (PG). The PG had a greater decrease in RV/LV (median change 0.396 (IQR, 0.347) vs. 0.207 (IQR, 0.306), p<0.001). In the cohort, 25 adverse events were reported (13.2%). The rate of complications did not differ between the 2 groups, with 15.1% in EG and 10% in PG. In terms of bleeding complications, GUSTO moderate bleeding was observed in 8 cases (5 in EG and 3 in PG), while severe bleeding was observed in 3 (2 in EG and 1 in PG), including 1 intracranial hemorrhage in the PG. ICU admissions were higher in the PG (p<0.001), but median hospital and ICU stays were comparable. No significant difference was found in the rate of in-hospital mortality (2.5% in EG, 4.3% in PG, p=0.672). Conclusion: Both CBT options are promising for treating submassive PE, with efficacy outcomes favoring Penumbra thrombectomy. Longer follow-up and randomized controlled trials are needed for definitive conclusions.

Modern Treatment of Pulmonary Embolism (USCDT vs MT): Results From a Real-World, Big Data Analysis (REAL-PE)

BackgroundAdvanced therapies are increasingly utilized to treat pulmonary embolism (PE). A unique data platform allows access to electronic health record data for comparison of the safety of PE therapies. MethodsAll data from Truveta (Truveta, Inc) were analyzed (16 systems, 83,612,413 patients, 535,567 with PE). All patients treated with ultrasound-assisted catheter-directed thrombolysis (USCDT) (Boston Scientific) or mechanical thrombectomy (MT) (Inari Medical) for PE were identified. The primary analysis was based on index procedures performed from January 2009 to May 2023, and contemporary analysis on those performed from January 2018 to May 2023. Bleeding was assessed via direct laboratory analysis and transfusion administration documentation. International Society for Thrombosis and Hemostasis (ISTH) and Bleeding Academic Research Consortium (BARC) 3b definitions were recreated. Multiple logistic regression analysis of major bleeding was performed. In-hospital death and median length of stay were measured. ResultsFor the primary analysis, 2259 patients (N = 1577 USCDT, N = 682 MT) and for the contemporary analysis 1798 patients (N = 1137 USCDT, N = 661 MT) met the criteria. Incidence of hemoglobin reduction (>2 and >5 g/dL) and transfusions received were significantly higher among MT-treated patients in both analyses, as was ISTH and BARC 3b major bleeding (primary: ISTH MT 17.3% vs USCDT 12.4% P = .002; BARC 3b MT 15.4% vs USCDT 11.8% P = .019) (contemporary: ISTH MT 17.2% vs USCDT 11.0% P = .0002; BARC 3b MT 15.4% vs USCDT 10.6% P = .002). Regression analysis demonstrated that MT is associated with major bleeding. Median length of stay, all-cause 30-day readmission and in-hospital mortality were similar between groups. Intracranial hemorrhage was more common with MT. ConclusionsMajor bleeding derived from direct laboratory and transfusion data occurred more frequently with MT vs USCDT. Intracranial hemorrhage was more common among MT-treated patients. In the absence of randomized data, these results provide guidance regarding the bleeding risk and safety of strategies for advanced PE therapy.

OC 53.5 Clinical Outcomes in Patients with Acute Pulmonary Embolism Undergoing Ultrasound-Assisted Catheter-Directed Thrombolysis

OC 53.5 Clinical Outcomes in Patients with Acute Pulmonary Embolism Undergoing Ultrasound-Assisted Catheter-Directed Thrombolysis

Outcomes of Catheter-Based Interventions for the Treatment of Intermediate to High-Risk Pulmonary Embolism in Patients With High Bleeding Risk: A Single-Centre Experience

Background Catheter-based reperfusion therapy is considered an alternative treatment for intermediate to high-risk pulmonary embolism (PE). These therapies can be divided into catheter-directed thrombolysis and catheter-based thrombectomy. High bleeding risk (HBR) were generally excluded from previous studies. Outcomes of these two treatment modalities in patients with high-risk PE are limited. Method This is a single centre retrospective cohort study of patients who were admitted for intermediate to high-risk PE and who were treated with catheter-based interventions due to contraindications for systemic thrombolysis. Baseline demographics, procedural details, clinical outcomes including 30 days PE-related mortality, and bleeding complications including blood transfusion and incidence of ICH were reported. Result 28 patients with acute PE (mean age 58 years) and contraindications for systemic thrombolysis were included in this study, of which 8 (28%) were high-risk. 14 patients (42.9% high and 57.1% intermediate-risk) were treated by aspiration thrombectomy (AT) and 14 (14.3% high and 85.7% intermediate-risk) by ultrasound-assisted catheter-directed thrombolysis (USCDT). There were 3 (10.7%) PE related mortality within 30 days. All of them were high-risk PE and in the USCDT arm. Overall incidence of moderate to severe bleeding was 41.7% (50% in AT and 21.4% in USCDT arm) and most of these patients required blood transfusion. The procedural time were 107.6 minutes for AT and 57.1 minutes for USCDT. Conclusion Catheter-based interventions with either aspiration thrombectomy or ultrasound assisted catheter-directed thrombolysis are viable treatment option for intermediate to high-risk pulmonary embolism in patients with high bleeding risk. Aspiration thrombectomy was associated with lower mortality rate in high-risk patients but higher incidence of blood transfusion and longer procedural time.

C-46 | In-Hospital Mortality in Patients With Pulmonary Embolism Managed With Ultrasound-Assisted Catheter-Directed Thrombolysis Compared to Systemic Thrombolysis

Patients with high-risk or intermediate-risk pulmonary embolism (PE) require more aggressive therapy, such as systemic thrombolysis. Although parenteral systemic thrombolysis leads to faster clot resolution, it is associated with a high risk for significant bleeding and its complications. The use of catheter-directed thrombolysis (CDT) decreases systemic exposure to thrombolytics and reduces the risk of complications and mortality. Adding ultrasound to CDT can potentially decrease the dosing of local thrombolytics and make it even safer for the patients. This retrospective cohort study identified 1,007 patients diagnosed with pulmonary embolism (PE) across several facilities. Patients were stratified into two groups based on the treatment they received, a group that received systemic thrombolysis (ST), 432 (42.9 %), and a group that received ultrasound-assisted catheter-directed thrombolysis (EKOS), 575 (57.1 %). The aim was to explore immediate mortality from direct and indirect complications arising from PE and its management in patients treated with systemic thrombolysis vs. EKOS. We used logistic regression to analyze data. The patients with PE and who were managed with ST were more likely to expire than those treated with EKOS (OR 2.893, CI 1.766∼5.041, p<0.001). Patients who passed were more likely to experience tachycardia (OR 2.432, CI 1,299∼4.556, p<0.001) and use of vasopressors (OR 13.331, CI 8.075∼22.006, p<0.001). There were 70 (6.95 %) deaths in the ST group vs. 26 (2.58 %) in the EKOS group. Patients with PE managed with ST are more likely to die than those managed with EKOS. This illustrates better outcomes of using EKOS vs. systemic thrombolysis for PE. However, a limitation of this study was the small sample of patients and possible cofounders, which warrants future studies.

Evolving paradigm of thrombolysis in pulmonary embolism: Comprehensive review of clinical manifestations, indications, recent advances and guideline.

Thrombolytic therapy has been the mainstay for patients with pulmonary embolism (PE). Despite being linked to a higher risk of significant bleeding, clinical trials demonstrate that thrombolytic therapy should be used in patients with moderate to high-risk PE, in addition to hemodynamic instability symptoms. This prevents the progression of right heart failure and impending hemodynamic collapse. Diagnosing PE can be challenging due to the variety of presentations; therefore, guidelines and scoring systems have been established to guide physicians to correctly identify and manage the condition. Traditionally, systemic thrombolysis has been utilized to lyse the emboli in PE. However, newer techniques for thrombolysis have been developed, such as endovascular ultrasound-assisted catheter-directed thrombolysis for massive and intermediate-high submassive risk groups. Additional newer techniques explored are the use of extracorporeal membrane oxygenation, direct aspiration, or fragmentation with aspiration. Because of the constantly changing therapeutic options and the scarcity of randomized controlled trials, choosing the best course of treatment for a given patient may be difficult. To help, the Pulmonary Embolism Reaction Team is a multidisciplinary, rapid response team that has been developed and is used at many institutions. Hence to bridge the knowledge gap, our review highlights various indications of thrombolysis in addition to the recent advances and management guidelines.

A Meta-analysis of Standard Versus Ultrasound-Assisted Catheter-Directed Thrombolysis in the Management of Acute Pulmonary Embolism.

Standard catheter-directed thrombolysis (SCDT) harnesses the therapeutic benefit of systemic thrombolytics while minimizing bleeding complications in patients presenting with pulmonary embolism (PE). Ultrasound-assisted catheter-directed thrombolysis (USAT) theoretically improves upon SCDT by disrupting fibrin and increasing the surface area exposed to thrombolytic agent. However, it is unclear if this translates into improved outcomes. A systematic search of prior publications comparing SCDT and USAT in patients with intermediate or high-risk PE was conducted. Primary outcomes of interest were bleeding events, ICU and hospital length of stay. Secondary outcomes included changes in pulmonary artery systolic pressure (PASP), mean pulmonary artery pressure (mPAP), and right ventricle to left ventricle diameter (RV/LV) ratio. Studies that lacked comparison groups were excluded. Bias assessments were performed using the Cochrane tools for randomized and nonrandomized studies. Data was collated utilizing the Cochrane Review Manager software, and all analyses assumed random effects. Our search yielded 7 observational studies and 1 randomized control trial. The studies included a total of 543 patients who underwent either SCDT (n = 273) or USAT (n = 270) for intermediate or high-risk PE. The synthesized analysis showed no significant differences in bleeding between the groups. There were no differences in ICU or hospital lengths of stay, changes in PASP, or mPAP. Reductions in RV/LV ratio were greater with SCDT (mean difference, -0.16; 95% CI, -0.27 to -0.06; P = .003). In comparison to SCDT, USAT did not result in improved clinical or hemodynamic outcomes in patients presenting with PE. Results were limited by heterogeneity among the included studies.

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.

A young Asian woman with thrombosis in the right renal vein and inferior vena cava: A rare case report and literature review

Renal vein thrombosis (RVT) is a rare clinical entity wherein a blood clot forms in one of the major renal veins or its tributaries. Patients with certain risk factors, such as adults with nephrotic syndrome and infants with dehydration, are susceptible to developing it. We present a young woman with primary thrombosis in the right renal vein and inferior vena cava. Hormonal therapy and the reception of the Medigen Vaccine Biologics Corporation coronavirus disease 2019 vaccine were the suspected risk factors for developing this disease. The primary thrombosis in the right renal vein and inferior vena cava was diagnosed using abdominal computed tomography (CT), and 90% of the thrombus in the right renal vein was dissolved after ultrasound-assisted catheter-directed thrombolysis followed by urokinase infusion for 1 week. Antibiotics and rivaroxaban were prescribed for 3 days and 5 months, respectively. Cryoprecipitate transfusions based on the level of fibrinogen were also prescribed. No long-term complications were noted in the clinic visits. We demonstrate the results of ultrasound-assisted catheter-directed thrombolysis using urokinase infusion for thrombosis in the right renal vein and inferior vena cava. Lastly, we review the literature discussing RVT relevant to this case. This study reveals the successful use of the novel technique, ultrasound-assisted catheter-directed thrombolysis using urokinase infusion, for the treatment of RVT.