Safety Evaluation of a Forward-Viewing Intravascular Transducer for Sonothrombolysis: An in Vitro and ex Vivo Study
2021, Ultrasound in Medicine and Biology
Citation Excerpt :
Finally, damage to blood vessels may cause internal hemorrhage in the patient, as well as exacerbate the coagulation pathway, resulting in the formation of new blood clots. Current clinical catheter-directed treatments for blood clots include mechanical thrombectomy, which can result in particle sizes >1 mm in diameter that can form hazardous emboli and may also cause endothelial damage themselves owing to mechanical perturbations or punctures (Sharafuddin and Hicks 1998; Muller-Hulsbeck et al. 2001, 2002; Chueh et al. 2013). Given the large variety of sonothrombolysis techniques that can be used with the same ultrasound (US) device (i.e., thrombolytic drug/tPA-mediated, microbubble-mediated and nanodroplet-mediated techniques), a systematic preclinical safety study is needed to directly compare the safety profiles of different sonothrombolysis techniques with the same device (Goel and Jiang 2020).
Recent in vitro work has revealed that a forward-viewing intravascular (FVI) transducer has sonothrombolysis applications. However, the safety of this device has yet to be evaluated. In this study, we evaluated the safety of this device in terms of tissue heating, vessel damage and particle debris size during sonothrombolysis using microbubbles or nanodroplets with tissue plasminogen activator, in both retracted and unretracted blood clots. The in vitro and ex vivo sonothrombolysis tests using FVI transducers revealed a temperature rise of less than 1°C, no vessel damage as assessed by histology and no downstream clot particles >500 µm. These in vitro and ex vivo results indicate that the FVI transducer poses minimal risk for sonothrombolysis applications and should be further evaluated in animal models.
Percutaneous Thrombectomy Devices in Thrombosed Dialysis Access
2011, Endovascular Surgery
Percutaneous Thrombectomy Devices in Thrombosed Dialysis Access
2010, Endovascular Surgery: Expert Consult
In Vitro Analysis of Downstream Particulates with Mechanical Thrombectomy Devices: Comparison of 20-kHz Sonothrombolytic and Rotating Dispersion Wire Systems
2009, Journal of Vascular and Interventional Radiology
Citation Excerpt :
In this study, the 20-kHz ultrasound-based device reduced a significantly larger proportion of clot to particulate sizes smaller than 10 μm than did the rotational dispersion device (93% vs 74%) and left significantly fewer particulates larger than 1,000 μm in its wake (1% vs 17% of the original thrombus burden). Müller-Hülsbeck et al (16) used clot modules of the same dimensions (30 cm × 7 mm diameter) as we did and found 0.6%–5.19% of the original thrombus mass retained on a combination or 1,000-, 100-, and 10-μm filters depending on the operating mode of the thrombectomy devices tested: Oasis (Boston Scientific, Watertown, Massachusetts), Hydrolyser (Cordis, Europe, Roden, The Netherlands), Amplatz Thrombectomy Device (Microvena, White Bear Lake, Minnesota), and AngioJet XPeedior (Possis Medical, Minneapolis, Minnesota). Clot weights of more than 1,000 μm were between 0.01 g ± 0.02 and 0.33 g ± 0.41 in the Müller-Hülsbeck experience and between 0.05 g ± 0.05 and 0.12 g ± 0.21 with the ST device and 1.16 g ± 1.05 and 1.48 g ± 0.91 with the RDW in our study.(Video) Mechanical Thrombectomy
To assess the potential of macroembolization, the authors compared the downstream particulate profile generated with use of two thrombectomy devices, a 20-kHz ultrasound-based sonothrombolytic (ST) device and a rotating dispersion wire (RDW).
An arterial flow model was pressurized to 100 mm Hg and perfused with 1,000 mL/min normal saline. Tubing containing 7-mm × 30-cm bovine thrombus proximal to a 75% stenosis was inserted distal to a nonstenosed bypass. The effluent was passed successively through 1,000-, 500-, and 200-μm filters and a particle analyzer. The ST device and RDW were activated for 10 and 15 minutes, respectively, in randomized sequences of experimental sets with and without the use of 10-mg tissue-type plasminogen activator (tPA). Results are expressed as means and standard deviations of fraction of lysed clot in each category.
The ST device produced significantly fewer particulates larger than 1,000 μm (1.3% ± 1.4) than did the RDW (16.8% ± 8.4, P < .001) and significantly more particulates smaller than 10 μm (90.7% ± 7.6) than did the RDW (73.9% ± 9.5; P < .001) at comparable thrombolytic efficacy (P = .982) and without significant effect from tPA (P = .988). There were no significant differences between particles measuring 500–1,000 μm (ST device: 0.3% ± 0.3, RDW: 0.4% ± 0.3; P = .653) and those measuring 10–199 μm (ST device: 7.5% ± 7.5, RDW: 8.6% ± 3.8; P = .624). The amount of particles on the 200-μm filter after RDW activation (0.4% ± 0.3) exceeded those trapped after use of the ST device (0.1% ± 0.1, P = .007) but contributed relatively little overall.See AlsoCOLLECTION DEVICE AND METHOD FOR STIMULATING AND STABILIZING A BIOLOGICAL SAMPLE专利检索- ...一次性阀专利检索查询-专利查询网
In this in vitro model, the use of the ST device resulted in fewer large particulates than did the use of the RDW, with more clots being reduced to less than 10 μm.
Percutaneous mechanical thrombectomy in the treatment of acute deep venous thrombosis
2007, The Vein Book
Percutaneous mechanical thrombectomy (PMT) refers to the technique in which a catheter utilizing mechanical means can be used independently or coupled with pharmacologic thrombolysis in the treatment of deep vein thrombosis (DVT). PMT offers many benefits in short-term therapy for DVT. Once the diagnosis of DVT is established, the goals of therapy are—prevention of PE, prevention of thrombus propagation, preservation of valvular function, and prevention of postthrombotic syndrome (PTS). Faster thrombus removal, smaller doses of thrombolytic agents, and shorter treatment times translate into improved symptom relief, decreased complications, and more efficient patient care. Additionally, more rapid thrombus resolution can potentially preserve valvular function, and decrease the incidence and severity of PTS. PMT should be considered first line therapy for patients presenting with DVT. Advanced endovascular skills, as well as being well versed in possible complications of PMT, are required to provide safe and effective patient care. Preliminary data shows that treatment with PMT may provide quicker thrombus resolution than catheter-directed thrombolysis (CDT) alone. With an increasing emphasis on minimal invasiveness, recent years have witnessed an endovascular revolution that has ushered in many different types of PMT catheters.
Prophylaxis and treatment of deep vein thrombosis in general surgery
2005, American Journal of Surgery
Citation Excerpt :
Some endoscopic devices that perform a hydrodynamic or mechanical thrombectomy have been recently developed (AngioJet [Possis Medical, Minneapolis, MN], Hydrolyser [Cordis Endovascular, Warren, NJ], Oasis [Boston Scientific/Medi-Tech, Natick, MA], and Amplatz Thrombectomy Device [Microvena, White Bear Lake, MN]). In vitro tests showed that all of the devices are efficient, with moderate differences in performance . However, the clinical studies of Vedantham et al found only a 26% rate thrombus removal when using mechanical thrombectomy alone compared to a substantial thrombus removal rate of 62% when using mechanical thrombectomy after pharmacologic thrombolytic agents had been administered .
Patients undergoing general surgery present an inherent risk of deep vein thrombosis (DVT). Evidence-based strategies for prevention and treatment of DVT should be continuously upgraded on the basis of good-quality recent trials.
Articles were identified using MEDLINE, EMBASE, and the Cochrane Library databases (January 1980 to July 2003). Randomized clinical trials and meta-analyses in which different prophylactic and treatment methods were compared for general surgery patients were selected.(Video) The evolution of mechanical thrombectomy approaches
In general surgery, low-molecular weight heparins (LMWHs) are relied upon more and more for prophylaxis and initial anticoagulant treatment of DVT, because of their multiple advantages in efficacy, safety, and convenience in handling. For cost-effective reasons, full-dose vitamin K antagonists are still preferred as the standard long-term anticoagulation method, while LMWHs represent the exception. Long-term use of low-intensity warfarin should be considered a new standard of care for the management of venous thrombosis. Compared to LMWH, the new anticoagulant molecules fondaparinux and ximelagatran seem to have similar efficacy in the treatment of venous thromboembolism, but they have a 2-fold increased efficacy in its prophylaxis. Clinical implementation of these new anticoagulant molecules depends on their cost-effectiveness; however, they have the potential to become the treatment of choice in the next decade. Thrombolysis has an unacceptable risk of hemorrhagic complications when used in the treatment of postoperative DVT. Furthermore, there are no data to prove that thrombolysis reduces the incidence of postthrombotic syndrome (PTS), despite early and complete recanalization achieved by thrombolysis. Surgical thrombectomy is only meant to decompress the venous hypertension consecutive to massive thrombosis (phlegmasia cerulea dolens) and thus to avoid venous gangrene. Other mechanical percutaneous thrombectomy devices are under evaluation. In selected cases, a combination treatment consisting of locoregional thrombolysis of the crurofemoral venous axis and mechanical thrombectomy of the pelvic venous axis achieves high rates of complete desobliteration.
Intravenous Thrombolysis Facilitates Successful Recanalization with Stent-Retriever Mechanical Thrombectomy in Middle Cerebral Artery Occlusions
Journal of Stroke and Cerebrovascular Diseases, Volume 25, Issue 4, 2016, pp. 954-959
Several factors influence the outcome after acute ischemic stroke secondary to proximal occlusions of cerebral vessels. Among others, noneligibility for intravenous thrombolysis (IVT) and incomplete revascularization have been identified as predictors of unfavorable outcome. The aim of this study was to investigate whether concomitant IVT influences the revascularization efficacy in mechanical thrombectomy (MT).
This study conducted a retrospective analysis of all consecutive patients presenting with an anterior circulation stroke due to large-artery occlusion with imaging evidence who were treated with MT between July 2012 and December 2013 at 2 high-volume stroke centers. Imaging data were regraded and re-evaluated according to the modified Treatment in Cerebral Ischemia scale and its respective vessel occlusion site definitions. Clinical end points included National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale; imaging and procedural measures were technical end points.
We identified 93 patients who presented with an occlusion of the middle cerebral artery (MCA): of these patients, 66 (71%) received IVT. We did not find statistically significant differences in the baseline NIHSS score, time from symptom onset to groin puncture, and age when comparing the IVT group with the non-IVT group. The rate of successful recanalizations (modified Treatment in Cerebral Ischemia score ≥ 2b) was significantly higher in patients with MCA occlusion and concomitant IVT (P = .01). Stepwise logistic regression identified IVT and thrombus length as predictive factors for successful mechanical recanalization (P = .004, P = .002).
IVT and thrombus length are predictive factors for a successful recanalization in MT for acute ischemic stroke with underlying MCA occlusion.
AngioJet Aspiration Thrombectomy Combined with Transcatheter Thrombolysis in Treatment of Acute Portal Venous Systemic Thrombosis
Annals of Vascular Surgery, Volume 66, 2020, pp. 362-369
This study set out to assess the feasibility, effectiveness, and safety of percutaneous AngioJet aspiration thrombectomy combined with transcatheter thrombolysis for treating acute portal venous systemic thrombosis (APVST).(Video) The EMBOTRAP® experience and First Pass efficacy in mechanical thrombectomy
Clinical data of 13 patients with APVST who were treated by AngioJet aspiration thrombectomy combined with transcatheter thrombolysis from March 2017 to July 2018 were analyzed retrospectively. The effect of portal venous recanalization was evaluated by intraoperative angiography and postoperative surveillance of clinical findings, portal venous ultrasound, or computed tomography.
Successful puncture of the portal vein (PV) was performed in all patients. The PV was punctured successfully in 7 patients via the transjugular intrahepatic route, 2 patients failed to be punctured and then had successful percutaneous transhepatic puncture, and 4 patients underwent percutaneous transhepatic PV puncture directly. The duration of thrombus aspiration was 238.46±89.89sec (range, 120–360), and the amount of urokinase in thrombus aspiration was 353,000±87,700 IU (range, 200,000–400,000). Portal venous thrombosis was dissolved by the AngioJet thrombectomy device (Boston Scientific, Marlborough, MA) in all patients. After aspiration, angiography showed that grade III lysis was achieved in 8 patients, grade II lysis in 1 patient, and grade I lysis in 4 patients. The length of transcatheter thrombolysis was 3.07±1.75days (range, 1–7), and the total urokinase dose via an indwelling catheter was 1,230,000±706,000 IU (range, 200,000–2,800,000). Four patients had a transjugular intrahepatic portosystemic shunt, 1 patient with stenosis of the superior mesenteric vein (SMV) achieved balloon angioplasty, and 1 patient with stenosis of the SMV was stented. Operative complications were transient hematuria (4 patients), palpitation (1 patient), and bowel resection (1 patient). No patients died within 30days. Patients were discharged at 12.00±5.83days (range, 6–27) after admission. All patients survived, and no recurrence developed during the follow-up of 9.15±3.18months (range, 4–15).
Percutaneous AngioJet aspiration thrombectomy combined with thrombolytic therapy is feasible and effective for APVST. This treatment is beneficial for APVST in dissolving thrombus, improving SMV flow, and relieving symptoms of PV hypertension.
Prior IV Thrombolysis Facilitates Mechanical Thrombectomy in Acute Ischemic Stroke
Journal of Stroke and Cerebrovascular Diseases, Volume 24, Issue 5, 2015, pp. 952-957
In acute ischemic stroke (AIS), bridging therapy, including intravenous thrombolysis (IVT) and mechanical thrombectomy (MET), appears to be very promising. However, data on the impact of IVT before the endovascular procedure are limited.
To examine the impact of IVT on the MET procedure, we compared the duration of this procedure, number of passes, recanalization rate, safety issues, and outcome in consecutively recruited patients either eligible for MET alone (intravenous fibrinolysis contraindication) or receiving MET preceded by IVT for proximal middle cerebral artery (MCA) occlusion within 6hours of stroke onset.
From January 2011 to June 2013, 68 cases with proximal MCA occlusion were available for analysis (MET alone, 40; IVT+MET, 28). The 2 groups did not differ significantly in baseline characteristics. The median National Institutes of Health Stroke Scale score at admission was 15 (10-20) for MET and 18 (13-19) for IVT+MET groups, respectively (P=.39). The median duration of the endovascular procedure (from groin puncture to recanalization) was significantly shorter in the IVT+MET group compared with that in MET alone (35 minutes [21-60] versus 60 minutes [25-91]; P=.043). The number of passes of the thrombectomy device per patient tended to be lower in the IVT+MET group than those in the MET group (P=.080). The IVT+MET group also had a higher rate of complete recanalization and a better outcome at 3months.
Prior IVT may facilitate the MET procedure. Further studies on MET in AIS should assess the direct impact of IVT on the endovascular procedure.
Mechanical thrombectomy with a novel stent retriever with multifunctional zones: Initial clinical experience with the NeVa™ thrombectomy device
Journal of Neuroradiology, Volume 47, Issue 4, 2020, pp. 301-305
The NeVa™ (Vesalio, Nashville, Tennessee) thrombectomy device is a CE-approved novel hybrid-cell stent retriever with offset enlarged openings coupled with functional zones and a closed distal end. The device was designed to incorporate and trap resistant emboli. The purpose was to determine the safety and efficacy of the NeVa™ stent.
Prospective data was collected on the first thirty consecutive patients treated at four stroke centers with NeVa™ as first line treatment between December 2017 and May 2018. Clinical outcome measures included re-perfusion scores after each pass, complications (per-procedural complications, device related adverse events, all intracerebral hemorrhage (ICH) and symptomatic ICH (sICH) on follow up imaging), 24 hour NIHSS, mRS at discharge and 90 days. Baseline data as well as treatment parameters were documented.(Video) Neuro Thrombectomy Procedure with 3D Revascularization Device
Mean presenting NIHSS was 16. Sites of primary occlusion were 10 ICA, 16 M1-MCA, 3 M2-MCA and one basilar. There were five tandem occlusions. Reperfusion outcomes after each NeVa pass; TICI ≥ 2b after first pass 63%, after 1 or 2 passes 83%, after 1 to 3 passes 90%. TICI 2c-3 after first pass 47%, after 1-2 passes 57%, after 1–3 passes 60%. TICI ≥ 2b after final pass 93%; TICI 2c-3, 63%. There were no device related serious averse events and no sICH. Clot material was partially or completely incorporated into the device after 70% passes. The mean 24 hour NIHSS was 7 and the 90 day mRS was 0–2 in 53%.
The NeVa™ device demonstrated a high rate of first pass complete reperfusion effect, a good safety profile and favorable 90 day clinical outcomes in this initial clinical experience.
Percutaneous Manual Aspiration Thrombectomy Followed by Stenting for Iliac Vein Compression Syndrome with Secondary Acute Isolated Iliofemoral Deep Vein Thrombosis: A Prospective Study of Single-session Endovascular Protocol
European Journal of Vascular and Endovascular Surgery, Volume 47, Issue 1, 2014, pp. 68-74
To evaluate the feasibility, safety, and effectiveness of single-session endovascular treatment with manual aspiration thrombectomy (MAT) as the first-line method of thrombus removal for iliac vein compression syndrome (IVCS) with secondary acute isolated iliofemoral deep vein thrombosis (DVT).
This was a prospective clinical study. Twenty-six patients (19 women, 7 men, mean age 54 years) with left-sided acute iliac–common femoral DVT secondary to IVCS were enrolled. All patients presented with leg swelling or pains. Endovascular treatment, consisting of MAT, balloon angioplasty, and stent placement, was performed in the same setting. Overnight antegrade thrombolysis was performed in patients with residual thrombus after MAT. Patients were followed up by ultrasonography. The mean follow-up period was 17.8 months (12–25 months).
Single-session endovascular procedures were performed successfully in all patients. The mean procedure time was 67 minutes (ranging from 45 to 90 minutes). Complete thrombus removal, including almost 100% of removal in 24 patients and little residual thrombus (<5%) in two, was achieved after repeated MAT. Thrombolysis was used in these two patients. Complete symptomatic relief was achieved in 25 patients (96%) and partial relief in one. The hospital stay ranged from 2 to 4 days (mean 2.7 days). Recurrent thrombosis within the stent was observed in one case and recanalized with thrombolysis. The 1-year primary and secondary patency rate was 96% and 100%, respectively. No symptomatic pulmonary embolization, bleeding, and venous reflux were observed. Five patients complained about transitory low back pains during balloon angioplasty.
Single-session endovascular treatment with MAT as the first-line thrombus removal method is feasible, safe, and effective for IVCS with secondary acute isolated iliofemoral DVT. Although limited, our experience suggests that patients thought to be at high risk of bleeding may be candidates for the present single-session endovascular protocol.
Coiling as a Rescue Strategy for Flow Diverter Prolapse into a Giant Intracranial Aneurysm
World Neurosurgery, Volume 133, 2020, pp. 392-397
Up to 3.2% of the adult population has an unruptured intracranial aneurysm (IA). Flow diversion is a relatively new treatment technique that is especially useful for large and morphologically unfavorable IAs.
A previously healthy woman aged 32 years presented with a 6-month history of ptosis and ophthalmoplegia of the left eye. A magnetic resonance imaging scan revealed a giant left internal carotid artery aneurysm. She was admitted for treatment using flow diversion. After delivery of the flow diverter (FD), prolapse of the proximal end of the stent into the aneurysmal sac was observed. FD stabilization was achieved by deploying multiple coils through a previously placed microcatheter to push the prolapsed end away from the aneurysmal lumen.
The patient had a favorable outcome, with reduction of preoperative mass effect symptoms and complete obliteration of the aneurysm persisting at the 3-month follow-up.(Video) Therapies stories - Memories of Mechanical Thrombectomy
Giant IAs remain one of the most daunting clinical problems to treat. FD displacement is a rare (0.5%–0.75%) and possibly fatal complication. Currently, no clinical guidelines exist for its management. Adjunctive coiling is a possible rescue strategy for stabilizing an FD that foreshortened and prolapsed into the aneurysmal sac. Further studies are needed to identify the best approach to this complication.
Copyright © 2001 Society of Interventional Radiology. Published by Elsevier Inc. All rights reserved.