Acute Massive and Submassive Pulmonary Embolism: Preliminary Validation of Aspiration Mechanical Thrombectomy in Patients with Contraindications to Thrombolysis

Current state of the interventional approach to acute pulmonary embolism

Massive pulmonary embolism (PE) is a disease with high mortality, therefore early diagnosis and treatment is essential to save lives. In the absence of contraindications, patients with massive PE (high risk) should be treated immediately with full-dose intravenous systemic thrombolysis. The subset of patients for whom systemic thrombolysis is not successful and who continue to present with haemodynamic compromise or those with contraindications may be candidates for various catheter-directed or surgical therapies. The decision algorithm in intermediate-high/submassive risk patients is complex and must be employed by a multidisciplinary team and success may depend on the experience of the medical specialists involved.

Comparison of Safety and Efficacy of Aspiration Thrombectomy and Ultrasound Accelerated Thrombolysis for Management of Pulmonary Embolism: A Systematic Review and Meta-Analysis

PURPOSE

To compare the safety and efficacy of mechanical thrombectomy (MT) and ultrasound-accelerated thrombolysis (USAT) in pulmonary embolism (PE) management by performing a systematic review of the literature.

MATERIALS AND METHODS

The PubMed database was searched to identify articles on Inari's FlowTriever and Penumbra's Indigo mechanical thrombectomy devices (Group A) and the Ekos Endovascular system (Group B). Outcomes variables analyzed include pre- and post-procedure RV/LV ratio, pre- and post-procedure pulmonary artery pressure, hospital length of stay, technical success, specific complications, and mortality rate. Mean values were calculated using the weighted mean approach. RevMan Version 5.4 (Cochrane Collaboration) was used to perform the meta-analysis for this study. Cochrane Collaboration's Risk of Bias (RoB 2.0) approach was used to perform a quality assessment of the included articles in order to verify the validity and reliability of the research.

RESULTS

27 studies were in Group A and 28 studies pertained to Group B. There were 1662 patients in Group A and 1273 patients in Group B. Both groups had similar technical success (99.6% vs 99.4%). Thrombectomy showed longer mean procedure time (73.03 ± 14.57 min vs 47.35 ± 3.15 min), lower mean blood loss (325.20 ± 69.15 mL vs 423.05 ± 64.95 mL), shorter mean ICU stay (2.35 ± 1.64 days vs 3.22 ± 1.27 days), and shorter mean overall hospital stay (6.94 ± 4.38 days vs 7.23 ± 2.31 days). EKOS showed greater mean change in Miller Index (9.05 ± 3.35 vs 4.91 ± 3.70) and greater mean change in pulmonary artery pressure (14.17 ± 6.35 mmHg vs 8.11 ± 4.39 mmHg).

CONCLUSION

Ultrasound accelerated thrombolysis and percutaneous mechanical thrombectomy are effective therapies for pulmonary embolism with comparable clinical outcomes.

Clinical Outcomes of Catheter-Directed Thrombolysis versus Mechanical Aspiration in Patients with Acute Pulmonary Embolism

PURPOSE

The objective of this study was to evaluate the safety and efficacy of catheter-directed thrombolysis (CDT) and mechanical aspiration (MA) for acute pulmonary embolism (PE).

METHODS

From February 2022 to October 2024, the clinical data of patients with high- and intermediate-risk PE who received endovascular therapy were retrospectively reviewed. Patients were categorized based on the treatment strategy.

RESULTS

Fifty-eight consecutive patients were identified. CDT was initiated in 29 patients, while the remaining 29 received MA treatment. The time of thrombolysis and the dosage of urokinase were both lower in the MA group (P <0.05). No differences were found in cardiac biomarkers after 48 hours, perioperative bleeding events, heart/valve injury, and mortality. The total cost of the MA group was much higher compared to CDT alone. The MA group showed better improvement in right ventricular (RV) function with a higher reduction in the right ventricular-to-left ventricular ratio (0.55 ± 0.46 vs. 0.13 ± 0.53, P = 0.017). No differences were found in the reduction of the CT obstruction index.

CONCLUSION

CDT and MA seem to have similar outcomes for patients with acute high- and intermediate-risk PE. MA is more effective in improving RV function with less thrombolysis time and fewer thrombolytics.

Dual-Energy CT as a Well-Established CT Modality to Reduce Contrast Media Amount: A Systematic Review from the Computed Tomography Subspecialty Section of the Italian Society of Radiology

Background: Our study aims to provide an overview of existing evidence regarding the image quality of dual-energy CT (DECT) employing reduced contrast media (CM) volumes, in comparison to single-energy CT (SECT) with standard CM loads. The advantages, indications, and possible applications of DECT were investigated from the perspective of providing better patient care, minimizing CM volume and managing CM shortage. Methods: In this systematic review (PRISMA methodology), PubMed and WOS were searched from January 2010 to January 2023 by two independent reviewers. The scan and CM characteristics, radiation dose, and results of quantitative (contrast to noise ratio, CNR, and signal to noise ratio, SNR) and qualitative assessment of image quality were collected. Sixty non-duplicated records eligible for full-text screening were examined. Results: Finally, 22 articles (1818 patients) were included. The average CM reduction with DECT ranged between 43.4 ± 11%. Despite the wide variability in CT scan protocols, no differences were found in radiation doses between DECT and SECT. Conclusions: DECT scanners allow the employment of lower CM volumes with equal or better image quality evaluated by quantitative and qualitative analyses and similar dose radiation compared to SECT. Using image reconstructions at low monochromatic energy levels, DECT increases iodine conspicuity and attenuation contributing to CM containment measures.

Episode Care Costs Following Catheter-Directed Reperfusion Therapies for Pulmonary Embolism: A Literature-Based Comparative Cohort Analysis

This analysis aimed to estimate 30-day episode care costs associated with 3 contemporary endovascular therapies indicated for treatment of pulmonary embolism (PE). Systematic literature review was used to identify clinical research reporting costs associated with invasive PE care and outcomes for ultrasound-accelerated thrombolysis (USAT), continuous-aspiration mechanical thrombectomy (CAMT), and volume-controlled-aspiration mechanical thrombectomy (VAMT). Total episode variable care costs were defined as the sum of device costs, variable acute care costs, and contingent costs. Variable acute care costs were estimated using methodology sensitive to periprocedural and postprocedural resource allocation unique to the 3 therapies. Contingent costs included expenses for thrombolytics, postprocedure bleeding events, and readmissions through 30 days. Through February 28, 2023, 70 sources were identified and used to inform estimates of 30-day total episode variable costs. Device costs for USAT, CAMT, and VAMT were the most expensive single component of total episode variable costs, estimated at $5,965, $10,279, and $11,901, respectively. Costs associated with catheterization suite utilization, intensive care, and hospital length of stay, along with contingent costs, were important drivers of total episode costs. Total episode variable care costs through 30 days were $19,146, $20,938, and $17,290 for USAT, CAMT, and VAMT, respectively. In conclusion, estimated total episode care costs after invasive treatment for PE are heavily influenced by device expense, in-hospital care, and postacute care complications. Regardless of device cost, strategies that avoid thrombolytics, reduce the need for intensive care unit care, shorten length of stay, and reduce postprocedure bleeding and 30-day readmissions contributed to the lowest episode costs.

Severe Traumatic Brain Injury and Pulmonary Embolism: Risks, Prevention, Diagnosis and Management

Severe traumatic brain injury (sTBI) is a silent epidemic, causing approximately 300,000 intensive care unit (ICU) admissions annually, with a 30% mortality rate. Despite worldwide efforts to optimize the management of patients and improve outcomes, the level of evidence for the treatment of these patients remains low. The concomitant occurrence of thromboembolic events, particularly pulmonary embolism (PE), remains a challenge for intensivists due to the risks of anticoagulation to the injured brain. We performed a literature review on sTBI and concomitant PE to identify and report the most recent advances on this topic. We searched PubMed and Scopus for papers published in the last five years that included the terms "pulmonary embolism" and "traumatic brain injury" in their title or abstract. Exclusion criteria were papers referring to children, non-sTBI populations, and post-acute care. Our search revealed 75 papers, of which 38 are included in this review. The main topics covered include the prevalence of and risk factors for pulmonary embolism, the challenges of timely diagnosis in the ICU, the timing of pharmacological prophylaxis, and the treatment of diagnosed PE.

A meta-analysis of outcomes of aspiration thrombectomy for high and intermediate-risk pulmonary embolism

BACKGROUND

Aspiration thrombectomy has gained popularity in patients with massive and sub-massive pulmonary embolism (PE) and having contraindications to thrombolysis.

METHODS

A meta-analysis was conducted including studies on aspiration thrombectomy in patients with high-risk and intermediate-risk PE. The pooled odds ratio for efficacy parameters, including change in heart rate, blood pressure and right ventricle/left ventricle (RV/LV) ratio, and safety parameters including major bleeding and stroke, was calculated using a random effects model.

RESULTS

The meta-analysis of 24 selected studies revealed that intermediate and high-risk pulmonary embolism (PE) patients demonstrated significant improvements: modified Miller score odds ratio of 10.60, mean pulmonary artery pressure reduction by 0.04 mm Hg, and an overall all-cause mortality odds ratio of 0.10. Considerable heterogeneity was observed in various outcomes.

CONCLUSION

Aspiration thrombectomy has success rates in both high-risk and intermediate-risk PE, however, procedural risks, including bleeding, must be anticipated.

Technical Feasibility of Suction Thrombectomy Using a Large-Bore Aspiration System in the Portomesenteric Venous System

PURPOSE

To assess technical feasibility and safety of portal vein thrombectomy with suction thrombectomy using a large-bore thrombectomy device for portomesenteric venous thrombosis (PMVT).

MATERIALS AND METHODS

After receiving approval from institutional review board, patients undergoing PMVT treatment using a large-bore aspiration thrombectomy device (Inari FlowTriever or ClotTriever) between July 2019 and June 2021 were identified at 2 medical centers. Charts were reviewed for demographic information, imaging findings, and procedural details. PMVT was categorized using the Yerdel grading system. The thrombectomy procedure was performed via transjugular access through the existing or a new transjugular intrahepatic portosystemic shunt (TIPS) or transsplenic or transhepatic approach. Technical success was defined as successful clot reduction and restoration of portal venous flow at the conclusion of the procedure. Patient outcomes based on clinical presentation, adverse events, and thrombectomy-associated adverse events were recorded.

RESULTS

Twenty patients, with a median age of 58 years (range, 23-72 years), underwent large-bore aspiration thrombectomy, which was technically successful in 19 of 20 (95%) patients. In 9 of 20 (45%) patients, 9 of 20 (45%) patients, and 2 of 20 (10%) patients, the 20-F, 16-F, and 24-F devices were used, respectively. Fourteen patients had a pre-existing TIPS, and 6 patients had a TIPS created. In 5 of 20 (25%) patients, overnight lysis was performed in conjunction with Inari thrombectomy. Thrombus resolution with restoration of flow was achieved in 19 of 20 (95%) cases. There were no thrombectomy-associated adverse events. The mean follow-up time was 70 days (±113) at which time primary patency of the portal venous system was present in 16 of 20 (80%) patients.

CONCLUSIONS

Large-bore aspiration portal vein thrombectomy is feasible for PMVT.

Percutaneous thrombectomy in patients with intermediate- and high-risk pulmonary embolism and contraindications to thrombolytics: a systematic review and meta-analysis

Catheter-directed interventions have slowly been gaining ground in the treatment of pulmonary embolism (PE), especially in patients with increased risk of bleeding. The goal of this study is to summarize the evidence for the efficacy and safety of percutaneous thrombectomy (PT) in patients with contraindications to systemic and local thrombolysis. We performed a systematic review and meta-analysis using MEDLINE, Cochrane, Scopus and the Web of Science databases for studies from inception to March 2022. We included patients with intermediate- and high-risk PE with contraindications to thrombolysis; patients who received systematic or local thrombolysis were excluded. Primary endpoint was in-hospital and 30-day mortality, with secondary outcomes based on hemodynamic and radiographic changes. Major bleeding events were assessed as a safety endpoint. Seventeen studies enrolled 455 patients, with a mean age of 58.6 years and encompassing 50.4% females. In-hospital and 30-day mortality rates were 4% (95% CI 3-6%) and 5% (95% CI 3-9%) for all-comers, respectively. We found a post-procedural reduction in systolic and mean pulmonary arterial pressures by 15.4 mmHg (95% CI 7-23.7) and 10.3 mmHg (95% CI 3.1-17.5) respectively. The RV/LV ratio and Miller Index were reduced by 0.42 (95% CI 0.38-46) and 7.8 (95% CI 5.2-10.5). Major bleeding events occurred in 4% (95% CI 3-6%). This is the first meta-analysis to report pooled outcomes on PT in intermediate- and high-risk PE patients without the use of systemic or local thrombolytics. The overall mortality rate is comparable to other contemporary treatments, and is an important modality particularly in those with contraindications for adjunctive thrombolytic therapy. Further studies are needed to understand the interplay of anticoagulation with PT and catheter-directed thrombolysis.

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.

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.

Repeat angiography in patients undergoing conventional catheter-directed thrombolysis for submassive pulmonary embolism: a large single-center experience

PURPOSE

Few studies have examined conventional catheter directed thrombolysis (CDT) for the treatment of submassive pulmonary embolism (PE). Moreover, angiographic resolution of thrombus burden following CDT has infrequently been characterized. This study describes a single-center experience treating submassive PE with CDT while utilizing repeat angiography to determine treatment efficacy.

METHODS

A retrospective analysis of 140 consecutive patients who underwent CDT for submassive PE from December 2012 to June 2019 was performed. Angiographic resolution of thrombus burden after CDT was reported as high (>75%), moderate (51-75%), low (26-50%), or insignificant (≤25%). All angiograms were reviewed by two interventional radiologists. Secondary endpoints included reduction in pulmonary artery pressure (PAP) and clinical outcomes. Bleeding events were classified according to the Society of Interventional Radiology (SIR) adverse event criteria.

RESULTS

CDT was performed in 140 patients with a mean rtPA dose of 25.3 mg and a mean treatment time of 26.0 hours. Angiographic resolution of thrombus burden was high in 70.0%, moderate in 19.3%, low in 5.7%, and insignificant in 3.6%; in 2 patients (1.4%) repeat angiography was not performed. Systolic PAP was reduced (47 vs. 35 mmHg, p < 0.001), mean PAP was reduced (25 vs 21 mmHg, p < 0.001), and 129 patients (92.1%) improved clinically. Patients with high or moderate resolution of thrombus burden had a clinical improvement rate of 95.2%, while patients with low or insignificant thrombus burden resolution had a clinical improvement rate of 76.9% (p=0.011). Ten patients (7.1%) had hemodynamic or respiratory decompensation requiring mechanical ventilation, systemic thrombolysis, cardiopulmonary resuscitation, or surgical intervention. Seven patients (5.0%) experienced moderate bleeding events and one patient (0.7%) with metastatic disease developed severe gastrointestinal bleeding that resulted in death. Thirty-day mortality was 1.4%.

CONCLUSION

In patients with submassive PE undergoing CDT, angiographic resolution of thrombus burden is a safe and directly observable metric that can be used to determine procedural success. In this study, CDT with repeat angiography was associated with a 5.7% bleeding event rate and thirty-day mortality of 1.4%.

Aspiration thrombectomy for acute pulmonary embolism with an intermediate-high risk

INTRODUCTION AND PURPOSE

The treatment of acute pulmonary embolism (PE) with an intermediate-high risk of mortality at 30 days is still not well defined, recommending the latest clinical guidelines of the European Society of Cardiology 2019 exclusively anticoagulant treatment, reducing the indication for mechanical thrombectomy to high-risk patients or intermediate-high risk patients with poor hemodynamic evolution. Our purpose is to determine the safety and efficacy of aspiration thrombectomy in intermediate-high risk patients with PE and to analyze possible differences in these results between hemodynamically unstable patients (massive PE) and hemodynamically stable patients (submassive PE).

METHODS

We analyzed all patients who underwent aspiration thrombectomy for PE at our tertiary university hospital during a 34-month period. We compared echocardiographic parameters (right ventricular diameter, tricuspid plane annular plane systolic excursion (TAPSE), S' wave, and pulmonary hypertension), respiratory parameters (PaO₂/FiO₂ ratio), and clinical parameters recorded before and 24h after the procedure. We also analyzed bleeding complications and mortality.

RESULTS

In the 42 patients included (16 with massive PE and 26 with submassive PE), aspiration thrombectomy resulted in significant improvements in right ventricular diameter, TAPSE, S' wave, andPaO₂/FiO₂ ratio. Of the 8 patients administered fibrinolysis, 4 developed bleeding complications. Only one direct complication of the procedure was observed (pulmonary artery rupture). Eight patients died in the acute phase.

CONCLUSIONS

Aspiration thrombectomy for PE is safe and effective, significantly improving respiratory and hemodynamic parameters in the first 24h after the procedure with a low rate of complications compared to fibrinolysis.

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.

Endovascular treatment of acute ischemic stroke due to tandem lesions of the anterior cerebral circulation: a multicentric Italian observational study

PURPOSE

Acute ischemic stroke (AIS) due to tandem lesions (TLs) of extracranial Internal Carotid Artery and Anterior Cerebral Circulation are challenging for endovascular treatment (EVT). This study aims to evaluate feasibility, safety and efficacy of EVT for TLs' AIS, with or without emergent carotid artery stenting (eCAS), in a real-life scenario.

METHODS

Retrospective review of prospectively collected non-randomized thrombectomy databases from five stroke centers between 2015 and 2019. Consecutive patients with TLs' AIS were selected. Clinical, neuroimage and procedure features, as well as antiplatelet therapy regimen, were evaluated. Primary outcome was 90-day mRS ≤ 2. Secondary outcomes included: mTICI score 2b-3, extracranial recanalization, procedural complications, symptomatic intracerebral hemorrhage (SICH) and 90-day mortality.

RESULTS

Two hundred twenty-seven patients were enrolled (67.8% males; mean age 65.9 ± 12.9 years). We obtained mTICI 2b-3 in 77.1%, extracranial recanalization in 86.8%, 90-day mRS (available in 201/227 cases) ≤ 2 in 49.8%. Procedural complications occurred in 16.7%, SICH in 9.7%; 90-day mortality rate (available in 201/227 cases) was 14.4%. The strongest predictors of good clinical outcome were young age (p < 0.0001), low baseline NIHSS (p = 0.008), high baseline ASPECTS (p < 0.0001), good collateral flow (p = 0.013) and extracranial recanalization (p = 0.001). The most significant predictors of SICH were low baseline ASPECTS (p < 0.0001), occurrence of complications (p < 0.0001) and eCAS (p = 0.002).

CONCLUSION

In our real-life series, the EVT for TLs' AIS was feasible, safe and effective in improving 90-day functional outcome with acceptable morbi-mortality rates. ECAS increased the risk of SICH, independently from the antiplatelet therapy regimen.

Continuous Aspiration Thrombectomy in High- and Intermediate-High-Risk Pulmonary Embolism in Real-World Clinical Practice

Objectives

We sought to assess the technical and clinical feasibility of continuous aspiration catheter-directed mechanical thrombectomy (CDT) in patients with high- or intermediate-high-risk pulmonary embolism (PE).

Methods and Results

Fourteen patients (eight women and six men; age range: 29–71 years) with high- or intermediate-high-risk PE and contraindications to or ineffective systemic thrombolysis were prospectively enrolled between October 2018 and February 2020. The Indigo Mechanical Thrombectomy System (Penumbra, Inc., Alameda, California) was used as CDT device. Low-dose local thrombolysis (alteplase, 3–12 mg) was additionally applied in three patients. Technical and procedural success was achieved in 14 patients (100%). Complete or nearly complete clearance of pulmonary arteries was achieved in nine patients (64.3%), whereas partial clearance was achieved in five (35.7%). A significant improvement in the pre- and postprocedural patients' clinical status was observed in the following fields (median; interquartile range): heart rate (110; 100–120/min vs. 85; 80–90/min; p < 0.0001), systolic blood pressure (106; 90–127 mmHg vs. 123; 110–133 mmHg; p = 0.049), arterial oxygen saturation (88.5; 84.2–93% vs. 95.0; 93.8–95%, p = 0.0051), pulmonary artery systolic pressure (55; 44–66 mmHg vs. 42; 34–53 mmHg; p = 0.0015), Miller index score (21.5; 20–23 vs. 9.5; 8–13; p < 0.0001) and right ventricular/left ventricular ratio (1.3; 1.3–1.5 vs. 1.0; 0.9–1.0; p < 0.0001). No major periprocedural bleeding was detected.

Conclusions

CDT is a feasible and promising technique for management of high- or intermediate-high-risk PE to decrease thrombus burden, reduce right heart strain, and improve hemodynamic and clinical status. Some patients may benefit from simultaneous local low-dose thrombolytic therapy. Nevertheless, its criteria and role in CTD-managed patients require further elucidation.

Outcomes of Catheter-Directed Therapy Plus Anticoagulation Versus Anticoagulation Alone for Submassive and Massive Pulmonary Embolism

BACKGROUND

Catheter-directed therapy (CDT) offers an alternative treatment to systemic thrombolysis for patients with massive and submassive pulmonary embolism.

METHODS

A retrospective review of 105 consecutive massive and submassive pulmonary embolisms over 2 years was performed. Thirty-six patients (9 massive, 27 submassive) were treated with CDT, consisting of aspiration thrombectomy (18), ultrasound-assisted thrombolysis (8), or both (10). Forty-three patients (8 massive, 35 submassive) were treated with heparin anticoagulation alone. Primary outcome was improvement of RV/LV ratio 24-48 hours after treatment. Safety outcomes included 90-day mortality, bleeding complications, and hospital readmissions. Subgroup analysis based on severity of RV dilation was performed.

RESULTS

Mean RV/LV ratio decreased from 1.91±0.61 to 1.28±0.45 (P < .001) in the CDT group and from 1.40 ± 0.37 to 1.25 ± 0.32 (P = .01) in the anticoagulation group. In submassive pulmonary embolisms with mild and moderate RV dilation (RV/LV ratio 0.9-1.9), RV/LV ratio was significantly lower in the CDT group at 24-48 hours (1.05 ± 0.38 vs 1.20 ± 0.31, P < .001). In submassive pulmonary embolisms with severe RV dilation (RV/LV ratio >1.9), no difference was noted between the 2 treatment groups. Ninety-day mortality (11% and 14%, p = 0.7) and incidence of major bleeding complications did not significantly differ between the 2 groups. Thirty-day readmission rates were 8% in the CDT group and 26% in the anticoagulation group (P = .04).

CONCLUSION

CDT for acute massive and submassive pulmonary embolism significantly improves RV/LV ratio at 24-48 hours compared with anticoagulation alone and may lower hospital readmission rates. CDT may be more advantageous in patients with mild to moderate RV dilation.