Effect of Pharmacomechanical Catheter-Directed Thrombolysis on Segmental Artery Occlusions: Insights From the RESCUE Trial.

BACKGROUND: Reduction in distal vascular volume in acute pulmonary embolism (PE) is a significant predictor of 30- and 90-day mortality. The likely cause of this is pulmonary arterial obstruction. The effect of pharmacomechanical catheter-directed thrombolysis (PM-CDT) on the occlusions of these pulmonary artery (PA) branches is not known. OBJECTIVES: The RESCUE study evaluated PM-CDT with the Bashir endovascular catheter in patients with acute intermediate-risk PE. This analysis assessed PA occlusions using core laboratory data before and after PM-CDT therapy. METHODS: The baseline and 48-hour post-treatment contrast-enhanced chest computed tomography angiography of PE patients with right ventricular dilatation enrolled in the RESCUE trial were used. The primary analysis was the change in the number of segmental and proximal PA branches with total or subtotal (>65%) occlusions after 48 hours compared to baseline using McNemar's test. RESULTS: A total of 107 patients enrolled across 18 United States sites comprised this analysis. At 48 hours post-PM-CDT, the number of segmental PA branches with total or subtotal occlusions decreased from 40.5% to 11.7% (P < 0.0001). Proximal PA branch total or subtotal occlusions decreased from 28.7% to 11.0% (P < 0.0001). The reduction in segmental artery occlusions correlated significantly with the magnitude of reduction in right ventricular/left ventricular ratio (correlation coefficient of 0.287 [95% CI: 0.102-0.452]; P= 0.0026), whereas that in the proximal PA arteries did not (correlation coefficient of 0.132 [95% CI: 0.059-0.314] P= 0.173). CONCLUSIONS: PM-CDT with the Bashir catheter was associated with a significant reduction in total and subtotal occlusion of segmental and proximal PAs.

Impact of the IR/DR Primary Specialty Certification on Scientific Research in the Field.

Research is essential to the development, maintenance, and success of interventional radiology (IR) as a primary specialty. IR physicians must embrace a more sophisticated research approach toward the procedures we perform and the diseases we treat to accompany our elevated status. Identifying impactful research needs and directing a comprehensive research portfolio will anchor our position as an essential specialty within a thriving health care system. Doing so will ensure that this historic opportunity is maximized for the benefit of IR physicians, IR trainees, and, ultimately, IR patients.

Research Consensus Panel Follow-up: 8-Year Update on Submassive Pulmonary Embolism.

The 2015 Research Consensus Panel (RCP) on submassive pulmonary embolism (PE) set priorities for research in submassive PE and identified a rigorous randomized trial of catheter-directed therapy plus anticoagulation versus anticoagulation alone as the highest research priority. This update, written 8 years after the RCP was convened, describes the current state of endovascular PE practice and the Pulmonary Embolism-Thrombus Removal with Catheter-Directed Therapy trial, the main output from the RCP.

Genicular artery embolization for treatment of knee osteoarthritis pain: Systematic review and meta-analysis.

Objective: Genicular artery embolization (GAE) is a novel, minimally invasive procedure for treatment of knee osteoarthritis (OA). This meta-analysis investigated the safety and effectiveness of this procedure. Design: Outcomes of this systematic review with meta-analysis were technical success, knee pain visual analog scale (VAS; 0-100 scale), WOMAC Total Score (0-100 scale), retreatment rate, and adverse events. Continuous outcomes were calculated as the weighted mean difference (WMD) versus baseline. Minimal clinically important difference (MCID) and substantial clinical benefit (SCB) rates were estimated in Monte Carlo simulations. Rates of total knee replacement and repeat GAE were calculated using life-table methods. Results: In 10 groups (9 studies; 270 patients; 339 knees), GAE technical success was 99.7%. Over 12 months, the WMD ranged from -34 to -39 at each follow-up for VAS score and -28 to -34 for WOMAC Total score (all p â€‹< â€‹0.001). At 12 months, 78% met the MCID for VAS score; 92% met the MCID for WOMAC Total score, and 78% met the SCB for WOMAC Total score. Higher baseline knee pain severity was associated with greater improvements in knee pain. Over 2 years, 5.2% of patients underwent total knee replacement and 8.3% received repeat GAE. Adverse events were minor, with transient skin discoloration as the most common (11.6%). Conclusions: Limited evidence suggests that GAE is a safe procedure that confers improvement in knee OA symptoms at established MCID thresholds. Patients with greater knee pain severity may be more responsive to GAE.

Impact of Time to Intervention on Catheter-Directed Therapy for Pulmonary Embolism.

Cather-directed therapies (CDTs) are an evolving therapeutic option for patients with intermediate-risk pulmonary embolism (PE). Although many techniques have been studied, there is limited evidence for the impact of timing of intervention on patient outcomes. Our objective was to assess the association between time to CDT in patients presenting with PE on patient-related outcomes such as length of stay (LOS) and mortality. DESIGN: Retrospective cohort study. SETTING: Single academic center. PATIENTS: We identified patients for which the PE response team had been activated from January 2014 to October 2021. Patients were split into two cohorts depending on whether they went to CDT less than 24 hours from admission (early) versus greater than 24 hours (late). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data on demographics, timing of interventions, pulmonary hemodynamics, and outcomes were collected. Sixty-four patients were included in analysis. Thirty-nine (63.8%) underwent their procedure less than 24 hours from admission, whereas 25 (36.2%) underwent the procedure after 24 hours. The time from admission to CDT was 15.9 hours (9.1-20.3 hr) in the early group versus 33.4 (27.9-41) in the late group (p ≤ 0.001). There was a greater decrease in pulmonary artery systolic pressure after intervention in the early cohort (14 mm Hg [6-20 mm Hg] vs 6 mm Hg [1-10 mm Hg]; p = 0.022). Patients who received earlier intervention were found to have shorter hospital LOS (4 vs 7 d; p = 0.038) and ICU LOS (3 vs 5 d; p = 0.004). There was no difference in inhospital mortality between the groups (17.9% vs 12%; p = 0.523). CONCLUSIONS: Patients who underwent CDT within 24 hours of admission were more likely to have shorter hospital and ICU LOS. The magnitude of change in LOS between the two cohorts was not fully explained by the difference in time to CDT. There were modest improvements in pulmonary hemodynamics in the patients who underwent CDT earlier.

Unplanned 30-Day Readmissions after Management of Submassive and Massive Acute Pulmonary Embolism: Catheter-Directed versus Systemic Thrombolysis.

PURPOSE: To compare 30-day readmission and in-hospital outcomes from the Nationwide Readmissions Database (NRD) for catheter-directed thrombolysis (CDT) versus systemic intravenous thrombolysis (IVT) as treatments for acute submassive or massive pulmonary embolism (PE). MATERIALS AND METHODS: The NRD was queried from 2016 to 2019 for adult patients with nonseptic acute PE who underwent IVT or CDT. Massive PE was distinguished from submassive PE if patients had concurrent International Classification of Diseases (ICD-10) codes corresponding to mechanical ventilation, vasopressors, or shock. Propensity score-matched analysis was conducted to infer the association of CDT versus IVT in unplanned 30-day readmissions, nonroutine discharge, gastrointestinal bleeding (GIB), and intracranial hemorrhage (ICH). These results are demonstrated as average treatment effects (ATEs) of IVT compared with those of CDT. RESULTS: A total of 37,116 patients with acute PE were studied; 18,702 (50.3%) underwent CDT, and 18,414 (49.7%) underwent IVT. A total of 2,083 (11.1%) and 3,423 (18.6%) were massive PEs in the 2 groups, respectively (P < .001). The ATE of IVT was higher than that of CDT regarding unplanned 30-day readmissions (ATE, 0.019; P < .001), GIB (ATE, 0.012; P < .001), ICH (ATE, 0.003; P = .017), and nonroutine discharge (ATE, 0.022; P = .006). The subgroup analysis of patients with submassive PE demonstrated that IVT had a higher ATE regarding unplanned 30-day readmission (ATE, 0.028; P < .001), GIB (ATE, 0.008; P = .003), ICH (ATE, 0.002; P = .035), and nonroutine discharge (ATE, 0.019; P = .022) than CDT. CONCLUSIONS: CDT had a lower likelihood of unplanned 30-day readmissions, including when stratified by a submassive PE subtype. Additionally, adverse events, including ICH and GIB, were more likely among patients who received IVT than among those who received CDT.

Mechanical aspiration thrombectomy for the treatment of pulmonary embolism: A systematic review and meta-analysis.

INTRODUCTION: There are no randomized trials studying the outcomes of mechanical aspiration thrombectomy (MAT) for management of pulmonary embolism (PE). METHODS: We performed a systematic review and meta-analysis of existing literature to evaluate the safety and efficacy of MAT in the setting of PE. Inclusion criteria were as follows: studies reporting more than five patients, study involved MAT, and reported clinical outcomes and pulmonary artery pressures. Studies were excluded if they failed to separate thrombectomy data from catheter-directed thrombolysis data. Databases searched include PubMed, EMBASE, Web of Science until April, 2021. RESULTS: Fourteen case series were identified, consisting of 516 total patients (mean age 58.4 ± 13.6 years). Three studies had only high-risk PE, two studies had only intermediate-risk PE, and the remaining nine studies had a combination of both high-risk and intermediate-risk PE. Six studies used the Inari FlowTriever device, five studies used the Indigo Aspiration system, and the remaining three studies used the Rotarex or Aspirex suction thrombectomy system. Four total studies employed thrombolytics in a patient-specific manner, with seven receiving local lysis and 17 receiving systemic lysis, and 40 receiving both. A random-effects meta-analyses of proportions of in-hospital mortality, major bleeding, technical success, and clinical success were calculated, which yielded estimate pooled percentages [95% CI] of 3.6% [0.7%, 7.9%], 0.5% [0.0%, 1.8%], 97.1% [94.8%, 98.4%], and 90.7% [85.5%, 94.3%]. CONCLUSION: There is significant heterogeneity in clinical, physiologic, and angiographic data in the currently available data on MAT. RCTs with consistent parameters and outcomes measures are still needed.

Pharmacomechanical Catheter-Directed Thrombolysis With the Bashir Endovascular Catheter for Acute Pulmonary Embolism: The RESCUE Study.

BACKGROUND: Catheter-directed thrombolysis (CDT) has been associated with rapid recovery of right ventricular (RV) function. The Bashir catheter was developed for enhanced thrombolysis in large vessels such as the pulmonary arteries (PAs) with lower doses of tissue plasminogen activator (tPA). OBJECTIVES: The aim of this study was to evaluate the efficacy and safety of tPA infused using a pharmacomechanical (PM) CDT device called the Bashir endovascular catheter in patients with intermediate-risk acute pulmonary embolism (PE). METHODS: Patients with symptoms of acute PE with computed tomographic evidence of RV dilatation were enrolled. The Bashir catheter was used to deliver 7 mg tPA into each PA over 5 hours. The primary efficacy endpoint was the core laboratory-assessed change in computed tomographic angiography-derived RV/left ventricular (LV) diameter ratio at 48 hours, and the primary safety endpoint was serious adverse events (SAEs) including major bleeding at 72 hours. RESULTS: At 18 U.S. sites, 109 patients were enrolled. The median device placement time was 15 minutes. At 48 hours after PM-CDT, the RV/LV diameter ratio decreased by 0.56 (33.3%; P < 0.0001). PA obstruction as measured by the refined modified Miller index was reduced by 35.9% (P < 0.0001). One patient (0.92%) had 2 SAEs: a retroperitoneal bleed (procedure related) and iliac vein thrombosis (device related). Two other procedure-related SAEs were epistaxis and non-access site hematoma with anemia. CONCLUSIONS: PM-CDT with the Bashir endovascular catheter is associated with a significant reduction in RV/LV diameter ratio and a very low rate of adverse events or major bleeding in patients with intermediate-risk acute PE. The notable finding was a significant reduction in PA obstruction with low-dose tPA. (Recombinant tPA by Endovascular Administration for the Treatment of Submassive PE Using CDT for the Reduction of Thrombus Burden [RESCUE]; NCT04248868).

Antithrombotic Therapy After Venous Interventions: AJR Expert Panel Narrative Review.

Interventions for thrombotic and nonthrombotic venous disorders have increased with technical advances and more trained venous specialists. Antithrombotic therapy is essential to clinical and procedural success; however, postprocedural therapeutic regimens exhibit significant heterogeneity due to limited prospective randomized data and incomplete mechanistic understanding of the critical factors driving long-term patency. Postinterventional antithrombotic therapy for thrombotic venous disorders should adhere to existing venous thromboembolism management guidelines, which include 3-6 months of therapeutic anticoagulation at minimum and consideration of extended therapy in patients with higher risk of thrombosis because of procedural or patient factors. The added benefit of antiplatelet agents in the acute and intermediate period is unknown, having shown improved long-term stent patency in some retrospective studies. Dual- and/or triple-agent therapy should be limited based on individual risks of thrombosis and bleeding. The treatment of nonthrombotic disorders is more heterogeneous, though patients with limited flow, extensive stent material, or underlying prothrombotic states such as malignancy or chronic inflammation may benefit from single-agent or multiagent antithrombotic therapy. However, the agent, dose, and duration of therapy remain indeterminate. Future prospective studies are warranted to improve patient risk stratification and standardize postprocedural anti-thrombotic therapy in patients receiving venous interventions.

High incidence of patients lost to follow-up after venous thromboembolism diagnosis - Identifying an unmet need for targeted transition of care.

OBJECTIVES: Venous thromboembolism, including deep venous thrombosis and pulmonary embolism, is a major source of morbidity, mortality, and healthcare utilization. Given the prevalence of venous thromboembolism and its associated mortality, our study sought to identify factors associated with loss to follow-up in venous thromboembolism patients. METHODS: This is a single-center retrospective study of all consecutive admitted (inpatient) and emergency department patients diagnosed with acute venous thromboembolism via venous duplex examination and/or chest computed tomography from January 2018 to March 2019. Patients with chronic deep venous thrombosis and those diagnosed in the outpatient setting were excluded. Lost to venous thromboembolism-specific follow-up (LTFU) was defined as patients who did not follow up with vascular, cardiology, hematology, oncology, pulmonology, or primary care clinic for venous thromboembolism management at our institution within three months of initial discharge. Patients discharged to hospice or dead within 30 days of initial discharge were excluded from LTFU analysis. Statistical analysis was performed using STATA 16 (College Station, TX: StataCorp LLC) with a p-value of <0.05 set for significance. RESULTS: During the study period, 291 isolated deep venous thrombosis, 25 isolated pulmonary embolism, and 54 pulmonary embolism with associated deep venous thrombosis were identified in 370 patients. Of these patients, 129 (35%) were diagnosed in the emergency department and 241 (65%) in the inpatient setting. At discharge, 289 (78%) were on anticoagulation, 66 (18%) were not, and 15 (4%) were deceased. At the conclusion of the study, 120 patients (38%) had been LTFU, 85% of whom were discharged on anticoagulation. There was no statistically significant difference between those LTFU and those with follow-up with respect to age, gender, diagnosis time of day, venous thromboembolism anatomic location, discharge unit location, or anticoagulation choice at discharge. There was a non-significant trend toward longer inpatient length of stay among patients LTFU (16.2 days vs. 12.3 days, p = 0.07), and a significant increase in the proportion of LTFU patients discharged to a facility rather than home (p = 0.02). On multivariate analysis, we found a 95% increase in the odds of being lost to venous thromboembolism-specific follow-up if discharged to a facility (OR 1.95, CI 1.1-3.6, p = 0.03) as opposed to home. CONCLUSIONS: Our study demonstrates that over one-third of patients diagnosed with venous thromboembolism at our institution are lost to venous thromboembolism-specific follow-up, particularly those discharged to a facility. Our work suggests that significant improvement could be achieved by establishing a pathway for the targeted transition of care to a venous thromboembolism-specific follow-up clinic.

Indigo Aspiration System for Treatment of Pulmonary Embolism: Results of the EXTRACT-PE Trial.

OBJECTIVES: This study sought to prospectively evaluate the safety and efficacy of the Indigo aspiration system in submassive acute pulmonary embolism (PE). BACKGROUND: PE treatment with thrombolytics has bleeding risks. Aspiration thrombectomy can remove thrombus without thrombolytics, but data are lacking. METHODS: This study was a prospective, single-arm, multicenter study that enrolled patients with symptomatic acute PE ≤14 days, systolic blood pressure ≥90 mm Hg, and right ventricular-to-left ventricular (RV/LV) ratio >0.9. The primary efficacy endpoint was change in RV/LV ratio from baseline to 48 h post-procedure on core lab-adjudicated computed tomography angiography. The primary safety endpoint was a composite of 48-h major adverse events: device-related death, major bleeding, and device-related serious adverse events (clinical deterioration, pulmonary vascular, or cardiac injury). All sites received Institutional Review Board approval. RESULTS: A total of 119 patients (mean age 59.8 ± 15.0 years) were enrolled at 22 U.S. sites between November 2017 and March 2019. Median device insertion to removal time was 37.0 (interquartile range: 23.5 to 60.0) min. Two (1.7%) patients received intraprocedural thrombolytics. Mean RV/LV ratio reduction from baseline to 48 h post-procedure was 0.43 (95% confidence interval: 0.38 to 0.47; p < 0.0001). Two (1.7%) patients experienced 3 major adverse events. Rates of cardiac injury, pulmonary vascular injury, clinical deterioration, major bleeding, and device-related death at 48 h were 0%, 1.7%, 1.7%, 1.7%, and 0.8%, respectively. CONCLUSIONS: In this prospective, multicenter study the Indigo aspiration system was associated with a significant reduction in the RV/LV ratio and a low major adverse event rate in submassive PE patients. Intraprocedural thrombolytic drugs were avoided in 98.3% of patients. (Evaluating the Safety and Efficacy of the Indigo aspiration system in Acute Pulmonary Embolism [EXTRACT-PE]; NCT03218566).