Safety and efficacy of mechanical aspiration thrombectomy for patients with acute lower extremity ischemia.

OBJECTIVE: Acute limb ischemia (ALI) is associated with high rates of amputation and consequent morbidity and mortality. The objective of this study is to report on the safety and efficacy of aspiration thrombectomy using the Indigo Aspiration System in patients with lower extremity (LE) ALI. METHODS: The STRIDE study was an international, multicenter, prospective, study that enrolled 119 participants presenting with LE-ALI. Patients were treated firstline with mechanical thrombectomy using the Indigo Aspiration System, before stenting or angioplasty, or other therapies as determined by treating physician. The primary end point was target limb salvage at 30 days after the procedure. Secondary end points within 30 days included technical success, defined as core laboratory-adjudicated Thrombolysis in Myocardial Infarction (TIMI) 2/3 flow rate immediately after the procedure, changes in modified Society for Vascular Surgery runoff score, improvement of Rutherford classification compared with before the procedure, patency, rate of device-related serious adverse events, and major periprocedural bleeding. Secondary end points that will be evaluated at 12 months include target limb salvage and mortality. RESULTS: Of the 119 participants enrolled at 16 sites, the mean age was 66.3 years (46.2% female). At baseline (n = 119), ischemic severity was classified as Rutherford I in 10.9%, Rutherford IIa in 54.6%, and Rutherford IIb in 34.5%. The mean target thrombus length was 125.7 ± 124.7 mm. Before the procedure, 93.0% (of patients 107/115) had no flow (TIMI 0) through the target lesion. The target limb salvage rate at 30 days was 98.2% (109/111). The rate of periprocedural major bleed was 4.2% (5/119) and device-related serious adverse events was 0.8% (1/119). Restoration of flow (TIMI 2/3) was achieved in 96.3% of patients (105/109) immediately after the procedure. The median improvement in the modified Society for Vascular Surgery runoff score (before vs after the procedure) was 6.0 (interquartile range, 0.0-11.0). Rutherford classifications also improved after discharge in 86.5% of patients (83/96), as compared with preprocedural scores. Patency at 30 days was achieved in 89.4% of patients (101/113). CONCLUSIONS: In the STRIDE (A Study of Patients with Lower Extremity Acute Limb Ischemia to Remove Thrombus with the Indigo Aspiration System) study, aspiration thrombectomy with the Indigo System provided a safe and effective endovascular treatment for patients with LE-ALI, resulting in a high rate (98.2%) of successful limb salvage at 30 days, with few periprocedural complications.

Outcomes of Intravascular Lithotripsy in the Treatment of Chronic Limb-Threatening Ischemia: A Single-Center Retrospective Study.

PURPOSE: Vascular calcification is an important risk factor for endovascular treatment failure and complications in patients with chronic limb-threatening ischemia (CLTI). Intravascular lithotripsy (IVL) is a pulsatile balloon-based device that has emerged as a tool in the treatment of calcified vessels. The purpose of this study is to evaluate the efficacy and safety of IVL in the treatment of peripheral calcified lesions in CLTI patients. MATERIALS AND METHODS: A retrospective study was performed within a single institution. Thirty-six CLTI patients treated with IVL for peripheral calcified lesions from 2018 to 2022 were identified. Data on pre- and post-IVL luminal stenosis measured by digital subtraction angiography, lesion location, adjunctive therapies, ankle-brachial index (ABI), and intra-procedural complications were obtained. A total of 41 target lesions in twenty-eight patients were included, with ABI data available in 20 treated lower extremities. RESULTS: Across all 41 target lesions, IVL produced clinically significant luminal gain of 75.5% ± 23.0. Luminal gain by vessel location was 87.3% ± 15.8, 57% ± 25.7, and 78.5% ± 20.6 in the aortoiliac (n = 8), common femoral (n = 9), and femoropopliteal (n = 24) segments, respectively. Lesions treated with IVL alone yielded a luminal gain of 71.4% ± 25.6 (n = 10), while IVL alongside adjunctive therapy produced a luminal gain of 76.8% ± 22.4. In 20 treated lower extremities, ABI improvement of 0.20 ± 0.26 (p = 0.002) was recorded. Intra-procedural complications occurred in 1/36 patients, which was one instance of thrombus occurring prior to IVL. CONCLUSION: IVL may be an effective option for creating safe luminal gain and vessel preparation in patients with CLTI. Level of Evidence 2: Retrospective Cohort Study.

Endovascular Treatment of Infrainguinal Peripheral Arterial Disease (PAD): Update on Stent Technology.

Peripheral artery disease (PAD) is a progressive vascular disease affecting millions of individuals and is a considerable cause of morbidity and mortality worldwide. While balloon angioplasty remains the cornerstone option for endovascular management of arterial stenosis, advances in percutaneous endovascular stent technology have broadened the toolbox of therapeutic options for PAD and have significantly improved function and quality of life. Indeed, covered stents, bioabsorbable stents and drug eluting stents are several of the innovations in stent technology made since the advent of nitinol bare metal stents in the 1980s. The indications for use, technical considerations, treatment outcomes, and current concerns regarding current stent devices will herein be discussed in this review.

Alternative Access for Peripheral Arterial Disease: A Complete Review with Updates in Clinical and Technical Approaches.

Multiple or alternate arterial accesses are often required when tackling more challenging peripheral arterial disease (PAD). Knowledge and familiarity in performing antegrade femoral, popliteal, tibial, and upper extremity access can improve the success rate of complex PAD interventions. This article provides a detailed review of indications, technical how-tos, and outcomes of these alternative accesses.

Stent Graft Outcomes in Dialysis Circuits: A Review of Clinical Trials and Literature.

End-stage renal disease is a prevalent medical condition causing significant problems as the majority of patients are being treated with dialysis. While dialysis provides a means to compensate for the renal impairment, arteriovenous grafts and fistulas are often complicated by neointimal hyperplasia, loss of primary patency, and graft failure. Over the last decade, stent grafts have emerged as an alternative to balloon angioplasty and bare metal stents for revascularization in the event of arteriovenous graft occlusion or stenosis. Several randomized controlled trials have investigated the efficacy of stent grafts compared with balloon angioplasty for improving the function and durability of dialysis circuits. In this review, we present a comprehensive review of clinical trials. Stent grafts appear to offer increased primary patency over balloon angioplasty in the treatment of dialysis circuit stenosis. However, there is generally no significant difference between the two treatment modalities on other clinically relevant measures like complication rates and overall survival.

Evaluating the Balance Between Privacy and Access in Digital Information Sharing.

OBJECTIVES: Access to personal health records in an ICU by persons involved in the patient's care (referred to broadly as "family members" below) has the potential to increase engagement and reduce the negative psychologic sequelae of such hospitalizations. Currently, little is known about patient preferences for information sharing with a designated family member in the ICU. We sought to understand the information-sharing preferences of former ICU patients and their family members and to identify predictors of information-sharing preferences. DESIGN: We performed an internet survey that was developed by a broad, multidisciplinary team of stakeholders. Formal pilot testing of the survey was conducted prior to internet survey administration to study subjects. SETTING: Internet survey. SUBJECTS: Subjects included English-speaking adults who had an ICU experience or a family member with ICU experience between 2013 and 2016. We used panel sampling to ensure an ethnically representative sample of the U.S. population. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One thousand five hundred twenty surveys were submitted, and 1,470 were included in analysis. The majority of respondents (93.6%) stated that they would want to share present and past medical history, either all or that related to their ICU stay, with a designated family member of their choosing. The majority (79%) would also want their designated family member to be able to access that information from a home computer. Although most respondents preferred to share all types of information, they indicated varying levels of willingness to share specific types of more sensitive information. Information-sharing preferences did not differ by age, sex, ethnicity, or type of prior experience in the ICU (i.e., patient or family member). CONCLUSIONS: In the context of an ICU admission, sharing personal health information with a person of the patient's choosing appears desirable for most patients and family members. Policies and implementation of regulations should take this into consideration.

Radioembolization of Secondary Hepatic Malignancies.

Cancer has become the leading cause of mortality in America, and the majority of patients eventually develop hepatic metastasis. As liver metastases are frequently unresectable, the value of liver-directed therapies, such as transarterial radioembolization (TARE), has become increasingly recognized as an integral component of patient management. Outcomes after radioembolization of hepatic malignancies vary not only by location of primary malignancy but also by tumor histopathology. This article reviews the outcomes of TARE for the treatment of metastatic colorectal cancer, metastatic breast cancer, and metastatic neuroendocrine tumors, as well as special considerations when treating metastatic disease with TARE.

Improving IR Ergonomics Using a Flexible C-Arm System.

PURPOSE: To evaluate the impact of a versatile flexible ceiling-mounted C-arm on active table and gantry repositioning during interventions and its effect on operator discomfort, system usability, and patient safety compared with a traditional ceiling-mounted system. MATERIALS AND METHODS: There were 100 IR procedures studied: 50 in a traditional IR system (standard group) and 50 with a novel multiaxis ceiling-mounted system (test group). FlexArm was capable of multiple gantry rotation points allowing increased access to the patient in addition to 236 cm of lateral x-ray detector travel. For each procedure, both the table and the gantry repositioning were measured. Patient safety, patient/equipment repositioning effort, and physical discomfort were evaluated through an operator survey. RESULTS: Table repositioning was reduced from 42 to 16 instances per procedure (P < .001) in the test group compared with the standard group. The operators perceived less table and gantry repositioning effort (P < .0001) and decreased risks of equipment collisions, displacement of vascular access, and dislodgment of tubes/lines with the test group (P < .0001). Operator discomfort was reduced for all body areas in the test group over the standard group (P < .0001). CONCLUSIONS: The FlexArm system geometry enhances operator ergonomics, as there was a decrease need to move the table, leading to a perceived decrease in patient risk and decrease operator physical discomfort when compared to a traditional imaging system.

Needle track seeding in renal mass biopsies.

A review and analysis of the literature demonstrates that needle track seeding in renal mass biopsy has been reported 16 times. This complication occurs almost exclusively among patients with papillary renal cell carcinoma. The incidence is associated with multiple punctures of the mass, the use of core needles of ≥20 gauge, and lack of a coaxial sheath. Needle tract seeding may be associated with tumor upstaging and a worse prognosis. Fine-needle aspiration has a significantly lower rate of needle track seeding compared with large core needle biopsy (>20-gauge needle). A more formalized risk-based system for interpreting renal mass fine-needle aspiration may be useful as clinicians choose among an increasing number of therapeutic options.

Endovascular management of iliac aneurysmal disease with hypogastric artery preservation.

Common iliac artery aneurysms (CIAAs) pose a challenge in endovascular aneurysm repair. Aneurysm repair of CIAA traditionally requires embolization of the ipsilateral hypogastric artery (HA). Symptoms of buttock claudication and more feared complications of pelvic ischemia make HA preservation an appealing addition to aneurysm repair. In this review, we discuss various methods of CIAA repair with devices specifically designed for aneurysm repair and other custom techniques of HA preservation.

Endovascular Treatment of Concurrent Bilateral Common and Internal Iliac Artery Aneurysms with Preserved Pelvic Circulation: Bilateral Iliac Branch Devices with Opposing Single Division Internal Iliac Artery Sparing.

An 83-year-old man with bilateral common iliac artery aneurysms (right, 3.0 cm; left, 2.7 cm), bilateral internal iliac artery aneurysms (right, 3.4 cm; left, 2.6 cm), and an abdominal aortic aneurysm (3.8 cm) was treated with an aortobi-iliac stent graft and bilateral iliac branch devices. The internal iliac components were extended into opposing posterior (left) and anterior (right) divisions of the internal iliac artery using stent grafts. Computed tomography angiography demonstrated that all aneurysms decreased or were stable in size with patent stent grafts at 1 month. The patient was asymptomatic without complications of pelvic ischemia at the last clinical follow-up at 6 months.

4D flow MRI, cardiac function, and T1 -mapping: Association of valve-mediated changes in aortic hemodynamics with left ventricular remodeling.

BACKGROUND: Patients with bicuspid aortic valve (BAV) show altered hemodynamics in the ascending aorta that can be assessed by 4D flow MRI. PURPOSE: Comprehensive cardiac MRI was applied to test the hypothesis that BAV-mediated changes in aortic hemodynamics (wall shear stress [WSS] and velocity) are associated with parameters of left ventricular (LV) remodeling. STUDY TYPE: Retrospective data analysis. POPULATION: Forty-nine BAV patients (mean age = 50.2 ± 13.5, 62% male). FIELD STRENGTH/SEQUENCE: Balanced steady-state free precession (bSSFP)-CINE, pre- and postcontrast T1 mapping with modified Look-Locker inversion recovery (MOLLI), time-resolved 3D phase-contrast (PC) MRI with three-directional velocity encoding (4D flow MRI) at 1.5 and 3T. ASSESSMENT: Quantification of LV volumetric data and myocardial mass, extracellular volume fraction (ECV), aortic valve stenosis (AS), and regurgitation (AR). 3D aortic segmentation, quantification of peak systolic velocities, and 3D WSS in the ascending aorta (AAo), arch, and descending aorta (DAo). STATISTICAL TESTS: Two-sided nonpaired t-test to compare subgroups. Pearson correlation coefficient for correlations between aortic hemodynamics and LV parameters. RESULTS: Of the 49 BAV patients, 35 had aortic valve dysfunction (AS [n = 7], AR [n = 16], both AS and AR [n = 12]). Mean systolic WSS in the AAo, peak systolic velocities in the AAo and arch, and LV mass were significantly higher (P < 0.001) in the AS/AR group compared to the patients without AS/AR. In the complete group, we observed significant relationships between increased LV mass and elevated peak systolic velocity (r = 0.57, r = 0.58; P < 0.001) and WSS in the AAo and arch, respectively (r = 0.54, r = 0.46; P < 0.001). We detected an association between ECV and WSS in the AAo (r = 0.38, P = 0.02). These relations did not hold true for patients without AV dysfunction. DATA CONCLUSION: AS and AR in BAV patients have a major impact on elevated aortic peak velocities and WSS that were associated with parameters of LV remodeling. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017.

Perioperative evaluation of regional aortic wall shear stress patterns in patients undergoing aortic valve and/or proximal thoracic aortic replacement.

OBJECTIVES: To assess in patients with aortopathy perioperative changes in thoracic aortic wall shear stress (WSS), which is known to affect arterial remodeling, and the effects of specific surgical interventions. METHODS: Presurgical and postsurgical aortic 4D flow MRI were performed in 33 patients with aortopathy (54 ± 14 years; 5 women; sinus of Valsalva (d_SOV)/midascending aortic (d_MAA) diameters = 44 ± 5/45 ± 6 mm) scheduled for aortic valve (AVR) and/or root (ARR) replacement. Control patients with aortopathy who did not have surgery were matched for age, sex, body size, and d_MAA (n = 20: 52 ± 14 years; 3 women; d_SOV/d_MAA = 42 ± 4/42 ± 4 mm). Regional aortic 3D systolic peak WSS was calculated. An atlas of WSS normal values was used to quantify the percentage of at-risk tissue area with abnormally high WSS, excluding the area to be resected/graft. RESULTS: Peak WSS and at-risk area showed low interobserver variability (≤0.09 [-0.3; 0.5] Pa and 1.1% [-7%; 9%], respectively). In control patients, WSS was stable over time (follow-up-baseline differences ≤0.02 Pa and 0.0%, respectively). Proximal aortic WSS decreased after AVR (n = 5; peak WSS difference ≤-0.41 Pa and at-risk area ≤-10%, P < .05 vs controls). WSS was increased after ARR in regions distal to the graft (peak WSS difference ≥0.16 Pa and at-risk area ≥4%, P < .05 vs AVR). Follow-up duration had no significant effects on these WSS changes, except when comparing ascending aortic peak WSS between ARR and AVR (P = .006). CONCLUSIONS: Serial perioperative 4D flow MRI investigations showed distinct patterns of postsurgical changes in aortic WSS, which included both reductions and translocations. Larger longitudinal studies are warranted to validate these findings with clinical outcomes and prediction of risk of future aortic events.

k-t accelerated aortic 4D flow MRI in under two minutes: Feasibility and impact of resolution, k-space sampling patterns, and respiratory navigator gating on hemodynamic measurements.

PURPOSE: To assess the performance of highly accelerated free-breathing aortic four-dimensional (4D) flow MRI acquired in under 2 minutes compared to conventional respiratory gated 4D flow. METHODS: Eight k-t accelerated nongated 4D flow MRI (parallel MRI with extended and averaged generalized autocalibrating partially parallel acquisition kernels [PEAK GRAPPA], R = 5, TRes = 67.2 ms) using four ky -kz Cartesian sampling patterns (linear, center-out, out-center-out, random) and two spatial resolutions (SRes1 = 3.5 × 2.3 × 2.6 mm3 , SRes2 = 4.5 × 2.3 × 2.6 mm3 ) were compared in vitro (aortic coarctation flow phantom) and in 10 healthy volunteers, to conventional 4D flow (16 mm-navigator acceptance window; R = 2; TRes = 39.2 ms; SRes = 3.2 × 2.3 × 2.4 mm3 ). The best k-t accelerated approach was further assessed in 10 patients with aortic disease. RESULTS: The k-t accelerated in vitro aortic peak flow (Qmax), net flow (Qnet), and peak velocity (Vmax) were lower than conventional 4D flow indices by ≤4.7%, ≤ 11%, and ≤22%, respectively. In vivo k-t accelerated acquisitions were significantly shorter but showed a trend to lower image quality compared to conventional 4D flow. Hemodynamic indices for linear and out-center-out k-space samplings were in agreement with conventional 4D flow (Qmax ≤ 13%, Qnet ≤ 13%, Vmax ≤ 17%, P > 0.05). CONCLUSION: Aortic 4D flow MRI in under 2 minutes is feasible with moderate underestimation of flow indices. Differences in k-space sampling patterns suggest an opportunity to mitigate image artifacts by an optimal trade-off between scan time, acceleration, and k-space sampling. Magn Reson Med 79:195-207, 2018. © 2018 International Society for Magnetic Resonance in Medicine.

Analysis of the Final DENALI Trial Data: A Prospective, Multicenter Study of the Denali Inferior Vena Cava Filter.

PURPOSE: To report the final 2-year data on the efficacy and safety of a nitinol retrievable inferior vena cava (IVC) filter for protection against pulmonary embolism (PE). MATERIALS AND METHODS: This was a prospective multicenter trial of 200 patients with temporary indications for caval filtration who underwent implantation of the Denali IVC filter. After filter placement, all patients were followed for 2 years after placement or 30 days after filter retrieval. The primary endpoints were technical success of filter implantation in the intended location and clinical success of filter placement and retrieval. Secondary endpoints were incidence of clinically symptomatic recurrent PE, new or propagating deep vein thrombosis (DVT), and filter-related complications including migration, fracture, penetration, and tilt. RESULTS: Filter placement was technically successful in 199 patients (99.5%). Filters were clinically successful in 190 patients (95%). The rate of PE was 3% (n = 6), with 5 patients having a small subsegmental PE and 1 having a lobar PE. New or worsening DVT was noted in 26 patients (13%). Filter retrieval was attempted 125 times in 124 patients and was technically successful in 121 patients (97.6%). The mean filter dwell time at retrieval was 200.8 days (range, 5-736 d). There were no instances of filter fracture, migration, or tilt greater than 15° at the time of filter retrieval or during follow-up. CONCLUSIONS: The Denali IVC filter exhibited high success rates for filter placement and retrieval while maintaining a low complication rate in this clinical trial.

Comparison of 4D flow and 2D velocity-encoded phase contrast MRI sequences for the evaluation of aortic hemodynamics.

The purpose of this study was to compare aortic flow and velocity quantification using 4D flow MRI and 2D CINE phase-contrast (PC)-MRI with either one-directional (2D-1dir) or three-directional (2D-3dir) velocity encoding. 15 healthy volunteers (51 ± 19 years) underwent MRI including (1) breath-holding 2D-1dir and (2) free breathing 2D-3dir PC-MRI in planes orthogonal to the ascending (AA) and descending (DA) aorta, as well as (3) free breathing 4D flow MRI with full thoracic aorta coverage. Flow quantification included the co-registration of the 2D PC acquisition planes with 4D flow MRI data, AA and DA segmentation, and calculation of AA and DA peak systolic velocity, peak flow and net flow volume for all sequences. Additionally, the 2D-3dir velocity taking into account the through-plane component only was used to obtain results analogous to a free breathing 2D-1dir acquisition. Good agreement was found between 4D flow and 2D-3dir peak velocity (differences = -3 to 6 %), peak flow (-7 %) and net volume (-14 to -9 %). In contrast, breath-holding 2D-1dir measurements exhibited indices significantly lower than free breathing 2D-3dir and 2D-1dir (differences = -35 to -7 %, p < 0.05). Finally, high correlations (r ≥ 0.97) were obtained for indices estimated with or without eddy current correction, with the lowest correlation observed for net volume. 4D flow and 2D-3dir aortic hemodynamic indices were in concordance. However, differences between respiration state and 2D-1dir and 2D-3dir measurements indicate that reference values should be established according to the PC-MRI sequence, especially for the widely used net flow (e.g. stroke volume in the AA).

SIRFLOX: Randomized Phase III Trial Comparing First-Line mFOLFOX6 (Plus or Minus Bevacizumab) Versus mFOLFOX6 (Plus or Minus Bevacizumab) Plus Selective Internal Radiation Therapy in Patients With Metastatic Colorectal Cancer.

PURPOSE: SIRFLOX was a randomized, multicenter trial designed to assess the efficacy and safety of adding selective internal radiation therapy (SIRT) using yttrium-90 resin microspheres to standard fluorouracil, leucovorin, and oxaliplatin (FOLFOX)-based chemotherapy in patients with previously untreated metastatic colorectal cancer. PATIENTS AND METHODS: Chemotherapy-naïve patients with liver metastases plus or minus limited extrahepatic metastases were randomly assigned to receive either modified FOLFOX (mFOLFOX6; control) or mFOLFOX6 plus SIRT (SIRT) plus or minus bevacizumab. The primary end point was progression-free survival (PFS) at any site as assessed by independent centralized radiology review blinded to study arm. RESULTS: Between October 2006 and April 2013, 530 patients were randomly assigned to treatment (control, 263; SIRT, 267). Median PFS at any site was 10.2 v 10.7 months in control versus SIRT (hazard ratio, 0.93; 95% CI, 0.77 to 1.12; P = .43). Median PFS in the liver by competing risk analysis was 12.6 v 20.5 months in control versus SIRT (hazard ratio, 0.69; 95% CI, 0.55 to 0.90; P = .002). Objective response rates (ORRs) at any site were similar (68.1% v 76.4% in control v SIRT; P = .113). ORR in the liver was improved with the addition of SIRT (68.8% v 78.7% in control v SIRT; P = .042). Grade ≥ 3 adverse events, including recognized SIRT-related effects, were reported in 73.4% and 85.4% of patients in control versus SIRT. CONCLUSION: The addition of SIRT to FOLFOX-based first-line chemotherapy in patients with liver-dominant or liver-only metastatic colorectal cancer did not improve PFS at any site but significantly delayed disease progression in the liver. The safety profile was as expected and was consistent with previous studies.

Technical Approach to Antegrade Femoral Access.

The number of endovascular procedures for treatment of peripheral arterial disease continues to increase as minimally invasive procedures have become the first-approach solution for lower extremity arterial lesions of any complexity, including Trans-Atlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease (TASC) II category C and D. Although the usual treatment strategy has been to access the contralateral common femoral artery (CFA), an ipsilateral, antegrade CFA approach has certain advantages. The greatest advantages are the decrease in the access-to-lesion distance, which in turn improves the mechanical advantage and responsiveness of the tools used to perform the intervention. In certain clinical situations such as prior endovascular aneurysm repair, aortobifemoral surgical bypass, iliac kissing stents, and aortoiliac occlusive disease, an antegrade approach may be mandatory. In this article, we describe our institutional thought process and techniques for performing a successful antegrade puncture of the CFA, as well as highlight some pitfalls and the associated complication rates of which to be aware.

The DENALI Trial: an interim analysis of a prospective, multicenter study of the Denali retrievable inferior vena cava filter.

PURPOSE: To assess safety and effectiveness of a nitinol retrievable inferior vena cava (IVC) filter in patients who require caval interruption to protect against pulmonary embolism (PE). MATERIALS AND METHODS: Two hundred patients with temporary indications for an IVC filter were enrolled in this prospective, multicenter clinical study. Patients undergoing filter implantation were to be followed for 2 years or for 30 days after filter retrieval. At the time of the present interim report, all 200 patients had been enrolled in the study, and 160 had undergone a retrieval attempt or been followed to 6 months with their filter in place. Primary study endpoints included technical and clinical success of filter placement and retrieval. Patients were also evaluated for recurrent PE, new or worsening deep vein thrombosis, and filter migration, fracture, penetration, and tilt. RESULTS: Clinical success of placement was achieved in 94.5% of patients (172 of 182), with a one-sided lower limit of the 95% confidence interval of 90.1%. Technical success rate of filter placement was 99.5%. Technical success rate of retrieval was 97.3%; 108 filters were retrieved in 111 attempts. In two cases, the filter apex could not be engaged with a snare, and one device was engaged but could not be removed. Filter retrievals occurred at a mean indwell time of 165 days (range, 5-632 d). There were no instances of filter fracture, migration, or tilt greater than 15° at the time of retrieval or 6-month follow-up. CONCLUSIONS: In this interim report, the nitinol retrievable IVC filter provided protection against pulmonary embolism, and the device could be retrieved with a low rate of complications.

Ultrasound-accelerated vs standard catheter-directed thrombolysis--a comparative study in patients with iliofemoral deep vein thrombosis.

PURPOSE: To compare the thrombolytic efficacy and safety of standard catheter-directed thrombolysis (CDT) and ultrasound (US)-accelerated thrombolysis (UAT) for the treatment of iliofemoral deep vein thrombosis (DVT). MATERIALS AND METHODS: All medical records of patients who underwent CDT or UAT for DVT between June 2004 and October 2011 at a single tertiary care center were reviewed. Target vein patency was graded according to a reporting standard by an independent interventional radiologist. RESULTS: CDT was performed in 19 patients and UAT in 64 patients. The baseline parameters and DVT characteristics, including the duration of symptoms, the location, and the extension did not differ significantly between groups. Both treatment modalities were associated with a similar substantial resolution of thrombus load (CDT = 89%; interquartile range [IQR], 70%-100%; UAT = 82%; IQR, 55%-92% (P = .560). No significant differences in the lytic drug infusion rates, the total lytic doses, the total infusion time, and the use of adjunctive procedures were observed between groups. Major and minor bleeding complications were observed in 8.4% and 4.8% of the patients, with no difference between the treatment groups (P = .709 and P = .918, respectively). During a median follow-up of 35 months (20-55 months), three deaths and 16 cases of repeated thrombosis were observed. The estimated mean event-free survival time was longer after CDT (69 mo) compared with UAT (33 mo) (log-rank test P = .310). CONCLUSIONS: The present study failed to prove any substantial clinical benefit provided by UAT with regard to effectiveness or safety compared with standard CDT. Given the added costs of the US delivery device, prospective randomized data are needed to justify its widespread use for DVT treatment.