Catheter-directed ultrasound-accelerated thrombolysis may be life-saving in patients with massive pulmonary embolism after failed systemic thrombolysis

Outcomes of catheter-directed embolectomy and surgical embolectomy for intermediate- to high-risk pulmonary embolism: a retrospective observational study

OBJECTIVE

Intermediate risk (IR)- and high risk (HR)-pulmonary embolism (PE) are associated with mortality rates that span 1.8% to 17% and greater than 31% respectively. Catheter-directed embolectomy (CDE) and surgical embolectomy (SE) for IR- and HR-PE offer alternatives to systemic thrombolysis, but data comparing CDE versus SE is limited. We assessed the outcomes of patients with acute PE who received CDE or SE for IR- and HR-PE.

METHODS

A retrospective review of all adult patients who had undergone CDE or SE for IR- and HR-PE in the Mount Sinai Health System between August, 2019 to June, 2022 was performed. Fisher's exact test and Student's t-test (or Mann-Whitney U-test) were used for comparing qualitative and quantitative outcomes respectively between the CDE and SE groups.

RESULTS

Fifteen (15) patients received SE, and 25 patients received CDE. Patients who received SE included 53% IR- and 47% HR-PE, while those who received CDE included 60% IR- and 40% HR-PE. CDE and SE had 96% and 100% technical success rates respectively. The 30-day all-cause mortality rates were 13.3% and 8% in the SE and CDE groups respectively (p > 0.05). The rates of major hemorrhagic complications in the CDE and SE groups were 4% and 26.7% respectively (p > 0.05).

CONCLUSION

CDE and SE were associated with high technical success rates in patients with IR- and HR-PE along with a low risk of major complications and acceptable 30-day all-cause mortality rates. In the absence of significant contraindications, CDE may provide a less invasive alternative to SE.

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.

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.

Venoarterial Extracorporeal Membrane Oxygenation With or Without Advanced Intervention for Massive Pulmonary Embolism

INTRODUCTION

Massive pulmonary embolism (MPE) is a rare but highly fatal condition. Our study's objective was to evaluate the association between advanced interventions and survival among patients with MPE treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

This is a retrospective review of the Extracorporeal Life Support Organization (ELSO) registry data. We included adult patients with MPE who were treated with VA-ECMO during 2010-2020. Our Primary outcome was survival to hospital discharge; secondary outcomes were ECMO duration among survivors and rates of ECMO-related complications. Clinical variables were compared using the Pearson chi-square and Kruskal-Wallis H tests.

RESULTS

We included 802 patients; 80 (10%) received SPE and 18 (2%) received CDT. Overall, 426 (53%) survived to discharge; survival was not significantly different among those treated with SPE or CDT on VA-ECMO (70%) versus VA-ECMO alone (52%) or SPE or CDT before VA-ECMO (52%). Multivariable regression found a trend towards increased survival among those treated with SPE or CDT while on ECMO (AOR 1.8, 95% CI 0.9-3.6), but no significant correlation. There was no association between advanced interventions and ECMO duration among survivors, or rates of ECMO-related complications.

CONCLUSION

Our study found no difference in survival in patients with MPE who received advanced interventions prior to ECMO, and a slight non-significant benefit in those who received advanced interventions while on ECMO.

A patient with pulmonary embolism takes a surprising HIT: a case report

Background

Venous thromboembolism (VTE) is a common condition that may manifest as intermediate or high-risk pulmonary embolism (PE), requiring either primary or subsequent fibrinolytic therapy. In these cases, catheter-directed thrombolysis (CDT) has been shown to be beneficial.

Case summary

We present the case of a borderline obese but otherwise healthy 43-year-old male individual, who was admitted with acute intermediate- to high-risk PE requiring treatment with intravenous unfractionated heparin. After initial therapy failure, the patient received CDT, with subsequent clinical worsening, and a mixed result of imaging studies suggesting partial central worsening and partial peripheral improvement of the thrombotic burden and right ventricular (RV) function. After a multidisciplinary PE response team (PERT) consultation, the diagnosis of heparin-induced thrombocytopenia (HIT) with normal platelet levels was made. Therapy was changed to intravenous bivalirudin, with an excellent clinical response and complete recovery of RV function. The patient was discharged with oral rivaroxaban therapy, and on follow-up was otherwise well.

Discussion

Apparent failure of thrombolytic therapy for VTE warrants a clinical investigation into possible causes of a pro-thrombotic state. In this case, the diagnosis of HIT was surprising, especially due to only a mild decline in platelet levels that were well within normal range. We also acknowledge the significance of our PERT in the key diagnosis made in this case.

Clinical Outcomes of Patients with Intermediate-to-High-Risk Pulmonary Embolism Undergoing Ultrasound-Assisted Catheter-Based Fibrinolysis Therapy in a Mid-Term Follow-Up Period - A Retrospective Observational Study

OBJECTIVES

Endovascular therapy with ultrasound-assisted catheter-directed thrombolysis (UACDT) theoretically provides higher efficacy while reducing the bleeding risk compared with conventional systemic thrombolysis. The clinical outcomes of UACDT in treating intermediate-to-high-risk pulmonary embolism (PE) are lacking in an Asian population.

METHODS

Forty-two patients who presented with intermediate-to-high-risk PE received UACDT. The patients were divided into two groups based on the incidence of procedure-related bleeding events, and baseline demographics were compared between the two groups. A paired-Student's t test was conducted to evaluate the efficacy of UACDT. Univariate and multivariate logistic regression analyses were conducted to identify independent risk factors for significant bleeding events.

RESULTS

The average age was 58.93 ± 20.48 years, and 33.33% of the study participants were male. A total of 85.7% of the participants had intermediate-risk PE. Compared with pre-intervention pulmonary artery pressure, the mean pulmonary artery pressure decreased significantly (37.61 ± 9.57 mmHg vs. 25.7 ± 9.84 mmHg, p < 0.01) after UACDT. The cumulative total tissue plasminogen activator dosage and total infusion duration were 44.54 ± 20.55 mg and 39.14 ± 19.06 hours respectively. Overall, 21.43% of the participants had severe bleeding events during the endovascular fibrinolysis treatment period. Forward conditional multivariate logistic regression analysis revealed that the lowest fibrinogen level during thrombolysis was an independent factor associated with moderate-to-severe bleeding (odds ratio: 0.40, 95% confidence interval: 0.19-0.88, p = 0.02).

CONCLUSIONS

UACDT exhibited high efficacy, but resulted in a higher-than-expected bleeding rate in this real-world study of an Asian population. The lowest fibrinogen level during thrombolysis was an independent risk factor associated with procedure-related bleeding events.

Rescue catheter-based therapies for the treatment of acute massive pulmonary embolism after unsuccessful systemic thrombolysis

The management of acute massive pulmonary embolism (PE) patients who did not respond to systemic thrombolysis (ST) has not been well established. The present study aimed to investigate the safety and effectiveness of catheter-based therapies (CDT) in this condition. We conducted a retrospective study of PE patients after unsuccessful ST (UST) between January 2012 and January 2018. Massive PE was identified in 408 patients and treated with full-dose ST therapy. Thrombolysis at 36 h was judged to be unsuccessful in 52 patients. Four ineligible patients were excluded, and the remaining 48 patients underwent rescue CDT: 30 patients underwent thrombus fragmentation with a rotating pigtail catheter; 8 patients underwent Straub rotational thrombectomy; and 10 patients underwent AngioJet rheolytic thrombectomy. In total, 42 patients subsequently underwent CDT relative to reduced-dose thrombolysis. Pooled clinical success was achieved in 45 patients, and the time-to-clinical instability relief for CDT was short (i.e., 48 h). Clinical findings significantly improved with oxygen saturation and the shock index (p < 0.01). CDT resulted in a significant decrease in the right ventricular (RV)/left ventricular end-diastolic diameter ratio and the average number of patients with pulmonary hypertension (p < 0.01). None of the patients suffered major complications or procedure-related adverse events, and two patients experienced minor complications. During follow-up, RV function symptoms were uneventful. The present study found that CDT is a safe and effective modality for rescue management of massive PE in patients with clinical instability and RV dysfunction after UST, leading to improved clinical outcomes and RV function with a low complication rate.

Percutaneous mechanical thrombectomy in patients with high-risk pulmonary embolism and contraindications for thrombolytic therapy

Background High-risk pulmonary embolism is associated with a high early mortality rate. We report our experience with percutaneous mechanical thrombectomy in patients with high-risk pulmonary embolism and contraindications for thrombolytic therapy. Patients and methods This was a retrospective analysis of consecutive patients with high-risk pulmonary embolism and contraindications to thrombolytic therapy. They were treated with percutaneous mechanical thrombectomy which included thrombectomy and additional thrombus aspiration when needed. Clinical parameters and survival to discharge were measured. Results From November 2005 to September 2015 we treated 25 patients with a mean age of 62.6 ± 12.7 years, 64% were men. Mean simplified Pulmonary Embolism Severity Index was 2.9. Mean maximum lactate levels were 7.8 ± 6.6 mmol/L, vasopressors were used in 77%, and 59% needed mechanical ventilation. Mechanical treatment included thrombus fragmentation complemented with aspiration (56%) and aspiration using Aspirex®S catheter (44%). Local (5 patients; 20%) and systemic (3 patients; 12%) thrombolytics were used as a salvage therapy. We observed nonsignificant improvements in systemic blood pressure (100 ± 41 mm Hg vs 119 ± 34; p = 0.100) and heart frequency (99 ± 35 min-1 vs 87 ± 31 min-1; p = 0.326) before and after treatment, respectively. Peak systolic tricuspid pressure gradient was significantly lower after treatment (57 ± 14 mm Hg vs 31 ± 3 mm Hg; p = 0.018). Overall the procedure was technically successful in 20 patients (80%) and 17 patients (68%) survived to hospital discharge. Conclusions In patients with high-risk pulmonary embolism who cannot receive thrombolytic therapy, percutaneous mechanical thrombectomy is a promising alternative to reduce pulmonary artery pressure.

Nursing Care Practices for Patients With Pulmonary Embolism Undergoing Treatment With Ultrasound-Assisted Thrombolysis: An Integrative Review

BACKGROUND

Pulmonary embolism (PE) remains a common and life-threatening event. The use of ultrasound-assisted thrombolysis (USAT) for the delivery of thrombolytic agents to the clot has developed in the last 10 years. A search yielded no evidence-based practice guidelines for the nursing care of the patient with PE during and post USAT treatment and specifically when using the EKOS machine.

OBJECTIVE

The objective of this integrative review was to explore the literature and web for any information on the use of USAT for adults with PE both during and post treatment. Our goal was to examine nurse-specific practices to develop appropriate protocols.

METHODS

We conducted a search of PubMed, Web of Science, EBSCOhost, CINAHL, Google Scholar, and Google for any guidelines, observational studies, or experimental studies using USAT for PE in adults. Nurse authors independently reviewed the articles using a standardized data coding form. Information abstracted included sample and setting characteristics, access characteristics, medication, sheath removal, compression, and bleeding events.

RESULTS

Twenty-two articles, published in 2008-2019, met the eligibility criteria. Most studies were small retrospective studies at single sites. Variation existed on the clinician, the clinical area for placement, the amount and duration of delivery of medication, and where care was provided during the infusion. Few studies noted sheath removal or compression procedures. Fifteen studies reported 1 fatal, 12 major, 4 moderate, and 36 minor bleeding events at the catheter insertion sites.

CONCLUSION

There is lack of sufficient information for the development of nursing practice guidelines for this new technology.

Rationale for catheter-based therapies in acute pulmonary embolism

Pulmonary embolism (PE) is a common disease resulting in significant morbidity and mortality. High-risk features of PE are hypotension or shock, and early reperfusion is warranted to unload the strained right ventricle and improve clinical outcomes. Currently, systemic thrombolysis (ST) is the standard of care but is associated with bleeding complications. Catheter-based therapies (CDT) have emerged as a promising alternative having demonstrated to be equally effective while having a lower risk of bleeding. Several CDT are currently available, some combining mechanical properties with low-dose thrombolytics. Recent guidelines suggest that CDT may be considered in patients with high-risk PE who have high bleeding risk, after failed ST, or in patients with rapid haemodynamic deterioration as bail-out before ST can be effective, depending on local availability and expertise. In haemodynamically stable patients with right ventricular (RV) dysfunction (intermediate-risk PE), CDT may be considered if clinical deterioration occurs after starting anticoagulation and relative contraindications for ST due to bleeding risk exist. Decision on treatment modality should follow a risk-benefit analysis on a case by case base, weighing the risk of PE-related complications; i.e. haemodynamic deterioration vs. bleeding. As timely initiation of treatment is warranted to prevent early mortality, bleeding risk factors should be assessed at an early stage in all patients with acute PE and signs of RV dysfunction. To ensure optimal management of complex cases of PE and assess a potential CDT strategy, a multidisciplinary approach is recommended. A dedicated Pulmonary Embolism Response Team may optimize this process.

Catheter-directed Thrombolysis for Intermediate-Risk Pulmonary Embolism

Intermediate-risk pulmonary embolism is common and carries a risk of progression to hemodynamic collapse and death. Catheter-directed thrombolysis is an increasingly used treatment option, based largely on the assumptions that it is more efficacious than anticoagulation alone and safer than systemic thrombolysis. In this review, we critically analyze the published data regarding catheter-directed thrombolysis for the treatment of intermediate-risk pulmonary embolism. Catheter-directed thrombolysis reduces right heart strain and lowers pulmonary artery pressures more quickly than anticoagulation alone. The mortality for patients with intermediate-risk pulmonary embolism treated with catheter-directed thrombolysis is low, between 0% and 4%. However, similarly low mortality is seen with anticoagulation alone. Catheter-directed thrombolysis appears to be safer than systemic thrombolysis, and procedural complications are uncommon. Bleeding risk appears to be slightly higher than with anticoagulation alone. Randomized, controlled trials are needed to compare the efficacy and safety of catheter-directed thrombolysis versus anticoagulation for intermediate-risk pulmonary embolism. There is no evidence that catheter-directed thrombolysis decreases the incidence of chronic thromboembolic pulmonary hypertension. There is no evidence from clinical studies that ultrasound-assisted thrombolysis is more effective or safer than standard catheter-directed thrombolysis.

Local Ultrasound-Facilitated Thrombolysis in High-Risk Pulmonary Embolism: First Dutch Experience

Purpose

To provide insight into the current use and results of ultrasound-facilitated catheter-directed thrombolysis (USAT) in patients with high-risk pulmonary embolism (PE).

Introduction

Systemic thrombolysis is an effective treatment for hemodynamically unstable, high-risk PE, but is associated with bleeding complications. USAT is thought to reduce bleeding and is therefore advocated in patients with high-risk PE and contraindications for systemic thrombolysis.

Methods

We conducted a retrospective cohort study of all patients who underwent USAT for high-risk PE in the Netherlands from 2010 to 2017. Characteristics and outcomes were analyzed. Primary outcomes were major (including intracranial and fatal) bleeding and all-cause mortality after 1 month. Secondary outcomes were all-cause mortality and recurrent venous thromboembolism within 3 months.

Results

33 patients underwent USAT for high-risk PE. Major bleeding occurred in 12 patients (36%, 95% CI 22–53), including 1 intracranial and 3 fatal bleeding. All-cause mortality after 1 month was 48% (16/33, 95% CI 31–66). All-cause mortality after 3 months was 50% (16/32, 95% CI 34–66), recurrent venous thromboembolism occurred in 1 patient (1/32, 3%, 95% CI 1–16).

Conclusions

This study was the first to describe characteristics and outcomes after USAT in a study population of patients with high-risk PE only, an understudied population. Although USAT is considered a relatively safe treatment option, our results illustrate that at least caution is needed in critically ill patients with high-risk PE. Further research in patients with high-risk PE is warranted to guide patient selection.

Treatment of the acute severe pulmonary embolism using endovascular methods

Purpose

To present a single-centre experience with endovascular treatment of patients with severe symptoms secondary to acute pulmonary embolism (PE).

Material and methods

Twenty-five patients were treated due to contraindications or deficient effects of systemic thrombolytic therapy. The patients were treated with a combination of fragmentation and aspiration, only aspiration, or only fragmentation, and with catheter-directed thrombolytic therapy.

Results

The saturation was improved following treatment in all patients, except in one where the procedure could not be completed. There were no immediate or late procedure-related complications.

Conclusions

Endovascular treatment of severe PE is a safe and efficient option in patients with failing effect or contraindication to systemic thrombolysis.

Ultrasound-Assisted Catheter-Directed Thrombolysis for Submassive Pulmonary Embolism

PURPOSE

Catheter-directed thrombolysis (CDT) is a relatively new therapy for pulmonary embolism that achieves the superior clot resolution compared to systemic thrombolysis while avoiding the high bleeding risk intrinsically associated with that therapy. In order to examine the efficacy and safety of CDT, we conducted a retrospective cohort study of patients undergoing ultrasound-assisted CDT at our institution.

METHODS

The charts of 30 consecutive patients who underwent CDT as a treatment of pulmonary embolism at our institution were reviewed. Risk factors for bleeding during thrombolysis were noted. Indicators of the right heart strain on computed tomography and echocardiogram, as well as the degree of pulmonary vascular obstruction, were recorded before and after CDT. Thirty-day mortality and occurrence of bleeding events were recorded.

RESULTS

Nine (30%) patients had 3 or more minor contraindications to thrombolysis and 14 (47%) had major surgery in the month prior to CDT. Right ventricular systolic pressure and vascular obstruction decreased significantly after CDT. There was a significant decrease in the proportion of patients with right ventricular dilation or hypokinesis. Decrease in pulmonary vascular obstruction was associated with nadir of fibrinogen level. No patients experienced major or moderate bleeding attributed to CDT.

CONCLUSION

Catheter-directed thrombolysis is an effective therapy in rapidly alleviating the right heart strain that is associated with increased mortality and long-term morbidity in patients with pulmonary embolism with minimal bleeding risk. Catheter-directed thrombolysis is a safe alternative to systemic thrombolysis in patients with risk factors for bleeding such as prior surgery. Future studies should examine the safety of CDT in patients with contraindications to systemic thrombolysis.

Ultrasound and Intra-Clot Microbubbles Enhanced Catheter-Directed Thrombolysis in Vitro and in Vivo

Insufficient penetration of microbubbles (MBs) into the vessel-obstructing thrombi significantly reduces the effectiveness of ultrasound thrombolysis (UT). The widely performed catheter-directed therapy (CDT) makes it possible to increase the local concentration of MBs in the clot. In an occluded vessel with a bypass, treatment of fresh human whole blood clots with CDT-based UT (intra-clot injection of MBs and urokinase, with ultrasound exposure) resulted in a significantly higher percentage of weight loss (35.32 ± 15.42%), compared with CDT alone (19.64 ± 4.71%), non-CDT-based UT (systemic administration of urokinase and MBs, with ultrasound exposure, 8.79 ± 3.02%) and systemic thrombolysis (7.90 ± 2.14). Ultrasound and intra-clot MB enhancement of CDT was further confirmed by a rabbit IVC thrombolysis study, where CDT-based UT resulted in significantly more effective thrombolysis compared with CDT alone. In summary, combining CDT with intra-clot MB-induced acoustic cavitation can improve thrombolysis.

Ultrasound Assisted Catheter-Directed Thrombolysis of Acute Pulmonary Embolism: A Review of Current Literature

Pulmonary embolism continues as a very common and also presumably life-threatening disorder. For affected individuals with intermediate- as well as high-risk pulmonary embolism, catheter-based revascularization procedures have developed a possible substitute for systemic thrombolysis or for surgical embolectomy. Ultrasound-assisted catheter-directed thrombolysis is an innovative catheter-based approach; which is the main purpose of the present review article. Ultrasound-assisted catheter-directed thrombolysis is much more efficacious in reversing right ventricular dysfunction as well as dilatation in comparison to anticoagulation alone in individuals at intermediate risk. However, a direct comparison of ultrasound-assisted thrombolysis with systemic thrombolysis or surgical thrombectomy is not available. Ultrasound-assisted thrombolysis with early intrapulmonary thrombolytic bolus could also be successful in high-risk patients, but unfortunately, data from randomized trials is limited. This review article recapitulates existing information on ultrasound-assisted thrombolysis for acute pulmonary embolism.

Guided longer pulses from a diagnostic ultrasound and intraclot microbubble enhanced catheter-directed thrombolysis in vivo

The mechanism of ultrasound thrombolysis (UT) is generally attributed to cavitation. The insufficiency of microbubbles (MB) to serve as cavitation nuclei in the vessel-obstructing thrombi significantly reduces the effectiveness of UT. Taking advantage of the widely performed catheter-directed therapy (CDT), in a thrombo-embolized rabbit IVC model with a simultaneous catheter directed rt-PA thrombolysis procedure, guided moderate mechanical index longer pulses from a modified diagnostic ultrasound transducer, combined with an intraclot infusion of MB, significantly accelerated the thrombolysis process. The higher thrombolysis efficacy score and consistent elevated post-treatment plasma concentration level of D-Dimer, a product of fibrinolysis, both indicated the superiority of CDT + UT over CDT/UT alone. Pathologic examination of the treated occluded IVC segments revealed an almost complete dissolution of the thrombi treated with CDT + UT. There was no evidences of thrombo-embolism or local thrombus formation in the cardiac-pulmonary vessels. Combined with intraclot infusion of MB, guided longer pulse ultrasound from a diagnostic transducer is able to safely and significantly improve a catheter-directed thrombolysis procedure. It thus has the potential to achieve earlier clot removal, administration of a lower dosage of thrombolytic agent and, consequently, a lower incidence of thrombolysis-related side effects.

Long-term prognostic analysis of early interventional therapy for lower extremity deep venous thrombosis

The aim of the present study was to observe the long-term prognostic value of early interventional therapy for lower extremity deep venous thrombosis (LDVT). In total, 85 patients diagnosed with LDVT for the first time were consecutively selected (identified course of disease was <3 months), and were divided into the control group with 43 cases and the observation group with 42 cases according to different therapeutic methods. The control group received anticoagulation therapy and thrombolysis, or integrated surgical thrombectomy, a conventional open operation, while the observation group received comprehensive treatment, combining endovascular catheter-directed thrombolysis and thrombectomy. The therapeutic effects were compared. After treatment, the differences in circumference of the thigh and shank between the affected and unaffected extremities, and vein dysfunction score of the two groups were decreased compared with before treatment. In addition, the above indexes of the observation group were significantly lower than in the control group (P<0.05). The clinical effective rate and effective extent of the observation group were higher than those of the control group, and the differences were statistically significant (P<0.05). The occurrence rate of post-thrombotic syndrome in the observation group was lower than that of the control group, and there was no difference in comparison of grading. The recurrence rate and restenosis rate of the observation group were lower than in the control group, while the patency rate of the observation group was higher than that of the control group, and the differences were statistically significant (P<0.05). In conclusion, early catheter-directed invention of thrombolysis with thrombectomy for LDVT has good clinical effect in the short-term and long-term.