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At least 91 records · Page 5

Drug-Eluting Nitinol Stent Treatment of the Superficial Femoral Artery and Above-the-Knee Popliteal Artery (The Zilver PTX Single-Arm Clinical Study): A Comparison Between Diabetic and Nondiabetic Patients

Purpose: To describe the 1-year results of drug-eluting nitinol stent placement in the femoropopliteal artery of diabetic and nondiabetic patients. Materials and Methods: All patients enrolled in this prospective, multicenter study underwent paclitaxel-eluting stent placement for de novo or restenotic lesions of the superficial femoral and/or popliteal artery. Baseline and follow-up walking impairment questionnaire (WIQ) scores, Rutherford classifications, and ankle-brachial index (ABI) measurements were obtained. Follow-up was completed at 1, 6, and 12 months. Results: There were 285 diabetic patients and 502 nondiabetic patients treated. There were no significant differences in mean lesion length or lesion calcification between patient groups. Procedural success in both treatment groups was >97 %. There were no significant differences between diabetic and nondiabetic groups in Kaplan-Meier estimates of patency, event-free survival (EFS), or freedom from target lesion revascularization (TLR) at 6 and 12 months. Both groups experienced a significant increase in ABI and WIQ values after treatment, and these improvements were sustained to 12-month follow-up; however, nondiabetic patients had significantly greater 6- and 12-month WIQ scores compared with diabetic patients. Based on covariate analysis, the only factors shown to be significant and to negatively influence patency were longer lesion length (p = 0.009), higher Rutherford classification (p = 0.02), and lack of hypertension (p = 0.02); diabetic status was not found to be a significant factor. Conclusion: Diabetic and nondiabetic patients had similar estimates of primary patency, EFS, and freedom from TLR; however, diabetic patients showed less improvement in WIQ scores compared with nondiabetic patients.

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Clopidogrel Responsiveness in Patients Undergoing Peripheral Angioplasty

Purpose: To investigate the incidence and clinical significance of platelet responsiveness in patients receiving clopidogrel after peripheral angioplasty procedures. Materials and Methods: This prospective study included patients receiving antiplatelet therapy with clopidogrel 75 mg after infrainguinal angioplasty or stenting and who presented to our department during routine follow-up. Clopidogrel responsiveness was tested using the VerifyNow P2Y12 Assay. Patients with residual platelet reactivity units (PRU) {>=} 235 were considered as nonresponders (NR group NR), whereas patients with PRU < 235 were considered as normal (responders [group R]). Primary end points were incidence of resistance to clopidogrel and target limb reintervention (TLR)-free survival, whereas secondary end points included limb salvage rates and the identification of any independent predictors influencing clinical outcomes. Results: In total, 113 consecutive patients (mean age 69 {+-} 8 years) with 139 limbs were enrolled. After clopidogrel responsiveness analysis, 61 patients (53.9 %) with 73 limbs (52.5 %) were assigned to group R and 52 patients (46.1 %) with 66 limbs (47.5 %) to group NR. Mean follow-up interval was 27.7 {+-} 22.9 months (range 3-95). Diabetes mellitus, critical limb ischemia, and renal disease were associated with clopidogrel resistance (Fisher's exact test; p < 0.05). According to Kaplan-Meier analysis, TLR-free survival was significantly superior in group R compared with group NR (20.7 vs. 1.9 %, respectively, at 7-year follow-up; p = 0.001), whereas resistance to clopidogrel was identified as the only independent predictor of decreased TLR-free survival (hazard rate 0.536, 95 % confidence interval 0.31-0.90; p = 0.01). Cumulative TLR rate was significantly increased in group NR compared with group R (71.2 % [52 of 73] vs. 31.8 % [21 of 66], respectively; p < 0.001). Limb salvage was similar in both groups. Conclusion: Clopidogrel resistance was related with significantly more repeat interventions after peripheral angioplasty procedures.

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Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT in rabbit model.

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Transarterial Chemoembolization for Hepatocellular Carcinomas with Central Bile Duct Invasion: Safety, Prognosis, and Predictive Factors

PurposeTo assess the safety and effectiveness of transarterial chemoembolization (TACE) of patients who have hepatocellular carcinomas (HCCs) with central bile duct invasion.Materials and MethodsThe institutional review board approved this retrospective study and waived informed consent. Fifty-three patients, initially treated with TACE for HCCs with central bile duct invasion from January 1999 to September 2012, were included. Clinical, laboratory, and survival data were reviewed. Complications and hospitalization length were evaluated using the χ{sup 2} test, Fisher’s exact test, and logistic regression analysis. Survival was analyzed using the Kaplan–Meier method with log-rank test and Cox proportional hazard model.ResultsSeven patients experienced TACE-related major complications (severe post-embolization syndrome in 3, non-fatal sepsis in 3, and secondary bacterial peritonitis in 1). The overall major complication rate was 13.2 %, but there were no permanent adverse sequelae or deaths within 30 days. Serum total bilirubin ≥3.0 mg/dL was the only significant risk factor for long hospitalization [hazard ratio (HR) = 4.341, p = .022]. The median survival was 12.2 months. Extrahepatic metastasis (HR = 6.145, p < .001), international normalized ratio (PT-INR) ≥1.20 (HR = 4.564, p < .001), vascular invasion (HR = 3.484, p = .001), and intermediate tumor enhancement (HR = 2.417, p = .019) were significantly associated with shorter survival.ConclusionTACE can be a safe and effective treatment for patients who have HCCs with central bile duct invasion. In particular, long-term survival can be expected if patients have strongly enhancing tumors without poor prognostic factors such as extrahepatic metastasis, PT-INR prolongation, and vascular invasion.

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Percutaneous Creation of Bare Intervascular Tunnels for Salvage of Thrombosed Hemodialysis Fistulas Without Recanalizable Outflow

PurposeThis study aimed to retrospectively assess the efficacy of a bare intervascular tunnel for salvage of a thrombosed hemodialysis fistula. We examined the clinical outcomes and provided follow-up images of the bare intervascular tunnel.Materials and MethodsEight thrombosed fistulas lacked available recanalizable outflow veins were included in this study. These fistulas were salvaged by re-directing access site flow to a new outflow vein through a percutaneously created intervascular tunnel without stent graft placement. The post-intervention primary and secondary access patency rates were calculated using the Kaplan–Meier method.ResultsThe procedural and clinical success rates were 100 %. Post-intervention primary and secondary access patency at 300 days were 18.7 ± 15.8 and 87.5 ± 11.7 %, respectively. The mean follow-up period was 218.7 days (range 10–368 days). One patient died of acute myocardial infarction 10 days after the procedure. No other major complications were observed. Minor complications, such as swelling, ecchymosis, and pain around the tunnel, occurred in all of the patients.ConclusionsPercutaneous creation of a bare intervascular tunnel is a treatment option for thrombosed hemodialysis fistulas without recanalizable outflow in selected patients.

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Hepatic Tract Plug-Embolisation After Biliary Stenting. Is It Worthwhile?

PurposePTC and stenting procedures are associated with significant risks including life-threatening haemorrhage, sepsis, renal failure and high mortality rates. PTC tract closure methods are utilised to reduce haemorrhagic complications despite little evidence to support their use. The current study assesses the incidence of haemorrhagic complications following PTC and stenting procedures, both prior to and following the introduction of a dedicated expanding gelatin foam-targeted embolisation liver tract closure technique.Materials and MethodsHaemorrhagic complications were retrospectively identified in patients undergoing PTC procedures both prior to (subgroup 1) and following (subgroup 2) the introduction of a dedicated targeted liver tract closure method between 9/11/2010 and 10/08/2012 in a single tertiary referral centre. Mean blood Hb decrease following PTC was established in subgroups 1 and 2. Kaplan–Meier life-table analysis was performed to compare survival outcomes between subgroups using the log-rank test.ResultsHaemorrhagic complications were significantly reduced following the introduction of the targeted PTC tract closure method [(12 vs. 3 % of subgroups 1 (n = 101) and 2 (n = 92), respectively (p = 0.027)]. Mean blood Hb decrease following PTC was 1.40 versus 0.68 g/dL in subgroups 1 and 2, respectively (p = 0.069). 30-day mortality was 14 and 12 % in subgroups 1 and 2, respectively. 50 % of the entire cohort had died by 174 days post-PTC.ConclusionIntroduction of liver tract embolisation significantly reduced haemorrhagic complications in our patient cohort. Utilisation of this method has the potential to reduce the morbidity and mortality burden associated with post-PTC haemorrhage by preventing bleeding from the liver access tract.

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Use of a New Hybrid Heparin-Bonded Nitinol Ring Stent in the Popliteal Artery: Procedural and Mid-term Clinical and Anatomical Outcomes

PurposeTo report the immediate and mid-term clinical and anatomical outcomes of a novel, hybrid, heparin-bonded, nitinol ring stent (TIGRIS; Gore Medical) when used for the treatment of lesions located in the popliteal artery.Materials and MethodsThis was a prospective single-centre registry. Patients eligible for inclusion were individuals suffering from symptomatic popliteal arterial occlusive disease (Rutherford–Becker stage 3–6; P1–P3 segments) and treated with placement of the TIGRIS stent(s). Patients were prospectively scheduled for clinical review and duplex ultrasound follow-up after 6 and 12 months. Outcome measures included immediate technical success, primary vessel patency, in-stent binary restenosis (evaluable by Duplex at 50 % threshold; PSVR > 2.0), freedom from target lesion revascularization (TLR) and amputation-free survival (AFS) estimated by Kaplan–Meier (K–M) survival analysis. Cox proportional-hazards regression analysis was also performed to adjust for confounders and search for independent predictors of outcomes.ResultsFrom August 2012 to March 2014, a total of 54 popliteal TIGRIS stents were implanted in 50 limbs of 48 patients (27 men and 21 women; mean age 76.0 ± 1.7 years). Median Rutherford–Becker stage was five at baseline and 37/50 (74.0 %) were chronic total occlusions. Technical success was achieved in all cases (100 %). Stented lesion length was 114.2 ± 36.9 mm (range 6–20 cm). Median follow-up was 11.8 ± 0.8 months. After 12 months, primary patency of the TIGRIS stent was 69.5 ± 10.2 % with an 86.1 ± 5.9 % freedom from TLR and 87 ± 5.0 % AFS (K–M estimates).ConclusionThe TIGRIS hybrid heparin-bonded nitinol ring stent is a safe and effective endovascular option for complex occlusive disease of the popliteal artery.

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Mid-Term Outcomes of Endovascular Treatment for TASC-II D Femoropopliteal Occlusive Disease with Critical Limb Ischemia

PurposeThe purpose of the study was to assess the safety and midterm effectiveness of endovascular treatment in Trans-Atlantic Inter-Society Consensus II (TASC-II) D femoropopliteal occlusions in patients with critical limb ischemia (CLI).MethodsPatients with CLI who underwent endovascular treatment for TASC-D de novo femoropopliteal occlusive disease between September 2008 and December 2013 were selected. Data included anatomic features, pre- and postprocedure ankle-brachial index, duplex ultrasound, and periprocedural complications. Sustained clinical improvement, limb salvage rate, freedom from target lesion revascularization (TLR), and freedom from target extremity revascularization (TER) were assessed by Kaplan–Meier estimation and predictors of restenosis/occlusion with Cox analysis.ResultsThirty-two patients underwent treatment of 35 TASC-D occlusions. Mean age was 76 ± 9. Mean lesion length was 23 ± 5 cm. Twenty-eight limbs (80 %) presented tissue loss. Seventeen limbs underwent treatment by stent, 13 by stent-graft, and 5 by angioplasty. Mean follow-up was 29 ± 20 months. Seven patients required major amputation and six patients died during follow-up. Eighteen endovascular and three surgical TLR procedures were performed due to restenosis or occlusion. Estimated freedom from TLR and TER rates at 2 years were 41 and 76 %, whereas estimated primary and secondary patency rates were 41 and 79 %, respectively.ConclusionsEndovascular treatment for TASC II D lesions is safe and offers satisfying outcomes. This patient subset would benefit from a minimally invasive approach. Follow-up is advisable due to a high rate of restenosis. Further follow-up is necessary to know the long-term efficacy of these procedures.

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Comparison of Technical and Clinical Outcome of Transjugular Portosystemic Shunt Placement Between a Bare Metal Stent and a PTFE-Stentgraft Device

PurposeTo analyse technical and clinical success of transjugular intrahepatic portosystemic shunt (TIPS) in patients with portal hypertension and compare a stent and a stentgraft with regard to clinical and technical outcome and associated costs.Materials and Methods170 patients (56 ± 12 years, 32.9 % females) treated with TIPS due to portal hypertension were reviewed. 80 patients received a stent (group 1) and 83 a stentgraft (group 2), and seven interventions were unsuccessful. Technical data, periprocedural imaging, follow-up ultrasound and clinical data were analysed with focus on technical success, patency, clinical outcome and group differences. Cost analysis was performed.ResultsPortal hypertension was mainly caused by ethyltoxic liver cirrhosis with ascites as dominant symptom (80 %). Technical success was 93.5 % with mean portosystemic gradient decrease from 16.1 ± 4.8 to 5.1 ± 2.1 mmHg. No significant differences in technical success and portosystemic gradient decrease between the groups were observed. Kaplan–Meier analysis yielded significant differences in primary patency after 14 days, 6 months and 2 years in favour of the stentgraft. Both groups showed good clinical results without significant difference in 1-year survival and hepatic encephalopathy rate. Costs to establish TIPS and to manage 2-year follow-up with constant patency and clinical success were 8876 € (group 1) and 9394 € (group 2).ConclusionTIPS is a safe and effective procedure to manage portal hypertension. Stent and stentgraft enabled good technical and clinical results with a low complication rate. Primary patency rates are clearly in favour of the stentgraft, whereas the stent was more cost effective with similar clinical results in both groups.

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The Impact of Tunneled Catheters for Ascites and Peritoneal Carcinomatosis on Patient Rehospitalizations

PurposeThe aim of the study is to assess patient outcomes, complications, impact on rehospitalizations, and healthcare costs in patients with malignant ascites treated with tunneled catheters.Materials and MethodsA total of 84 patients with malignant ascites (mean age, 60 years) were treated with tunneled catheters. Patients with peritoneal carcinomatosis and malignant ascites treated with tunneled drain catheter placement over a 3-year period were studied. Overall survival from the time of ascites and catheter placement were stratified by primary cancer and analyzed using the Kaplan–Meier method. Complications were graded by the Common Terminology Criteria for Adverse Events v3.0 (CTCAE). The differences between pre- and post-catheter admissions, hospitalizations, and Emergency Department (ED) visits, as well as related inpatient expenses were compared using paired t tests.ResultsThere were no significant differences in gender, age, or race between different primary cancer subgroups. One patient (1 %) developed bleeding (CTCAE-2). Four patients (5 %) developed local cellulitis (CTCAE-2). Three patients (4 %) had prolonged hospital stay (between 7 and 10 days) to manage ascites-related complications such as abdominal distention, discomfort, or pain. Comparison between pre- and post-catheter hospitalizations showed significantly lower admissions (−1.4/month, p < 0.001), hospital stays (−4.2/month, p = 0.003), and ED visits (−0.9/month, p = 0.002). The pre- and post-catheter treatment health care cost was estimated using MS-DRG IPPS payment system and it demonstrated significant cost savings from decreased inpatient admissions in post-treatment period (−$9535/month, p < 0.001).ConclusionsTunneled catheter treatment of malignant ascites is safe, feasible, well tolerated, and cost effective. Tunneled catheter treatment may play an important role in improving patients’ quality of life and outcomes while controlling health care expenditures.

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Comparison of Balloon-Occluded Retrograde Transvenous Obliteration (BRTO) Using Ethanolamine Oleate (EO), BRTO Using Sodium Tetradecyl Sulfate (STS) Foam and Vascular Plug-Assisted Retrograde Transvenous Obliteration (PARTO)

PurposeTo compare the clinical outcomes of balloon-occluded retrograde transvenous obliteration (BRTO) using ethanolamine oleate (EO), BRTO using sodium tetradecyl sulfate (STS) foam, and vascular plug-assisted retrograde transvenous obliteration (PARTO).Materials and MethodsFrom April 2004 to February 2015, ninety-five patients underwent retrograde transvenous obliteration for gastric varices were analyzed retrospectively. BRTO with EO was performed in 49 patients, BRTO with STS foam in 25, and PARTO in 21. Among them, we obtained follow-up data in 70 patients. Recurrence of gastric varices was evaluated by follow-up endoscopy or CT. Medical records were reviewed for the clinical efficacy. Statistical analyses were performed by Kaplan–Meier method, Chi-square, Fisher’s, and Kruskal–Wallis tests.ResultsTechnical and clinical success was 94.7 %. As major complications, a hemoglobinuria and a death due to disseminated intravascular coagulation (DIC) were occurred in two patients with BRTO using EO. Recurrence occurred more frequently in PARTO group (P < 0.05). Recurrence occurred in three patients in BRTO using EO group and four patients in PARTO group with 3.2 and 32.8 % of each expected 1-year recurrence rates. There was no recurrence in BRTO using STS group. Abdominal pain occurred more frequently in BRTO using EO than BRTO using STS foam and PARTO (P < 0.05). Procedure time of PARTO was shorter than two conventional BRTOs (P < 0.05).ConclusionsBRTO using STS foam or PARTO is better than BRTO using EO for treatment of gastric varices in terms of complication or procedure time. However, PARTO showed frequent recurrence of gastric varices during the long-term follow-up rather than BRTO.

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Mortality and Rates of Secondary Intervention After EVAR in an Unselected Population: Influence of Simple Clinical Categories and Implications for Surveillance

IntroductionPost-EVAR surveillance has a major impact upon patients, carers and healthcare resources. We hypothesised that elective indication, on-IFU anatomy, use of a modern device or normal first CTA, or a combination of these categories, might predict a rate of secondary intervention low enough to alter current surveillance protocols.MethodsPatients undergoing EVAR in our institution between 01.05.2007 and 28.02.2013 were assessed. Data on indication (elective, emergency), anatomy relative to IFU, device, first month CTA result, secondary intervention and mortality were obtained. Kaplan–Meier charts of mortality and freedom from secondary intervention were produced. Statistical analysis was by log-rank test and Cox proportional hazard modelling.Results234 patients underwent EVAR (188 elective, 208 on-IFU). Most implants were Endurant (106) or Talent (98). 151 patients had a normal first CTA. By median follow-up of 38.6 months, 39 patients underwent secondary intervention. A normal first CTA and elective indication were significantly associated with reduced risk of secondary intervention (p < 0.001 and p = 0.042 respectively), but device type and placement on- or off-IFU were not. Elective placement with a normal first CTA was 93 % predictive of freedom from secondary intervention by 32 months post-EVAR. Of nine patients undergoing secondary intervention in this group, eight presented symptomatically.DiscussionIn optimal procedural circumstances with normal post-procedural imaging, only 7 % of patients undergoing EVAR require secondary intervention, a minority of which is driven by surveillance. These data support a change to surveillance more tailored to the individual patient, and highlight the need for further qualitative and quantitative research.

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Treatment of Metastatic Lymph Nodes in the Neck from Papillary Thyroid Carcinoma with Percutaneous Laser Ablation

PurposeTo assess the effectiveness of percutaneous laser ablation (PLA) of cervical lymph node metastases from papillary thyroid carcinoma.Materials and Methods24 patients (62.3 ± 13.2 year; range 32–80) previously treated with thyroidectomy, neck dissection, and radioiodine ablation underwent ultrasound-guided PLA of 46 {sup 18}FDG-PET/CT—positive metachronous nodal metastases. All patients were at high surgical risk or refused surgery and were unsuitable for additional radioiodine ablation. A 300 µm quartz fiber and a continuous-wave Nd-YAG laser operating at 1.064 mm were used. Technical success, rate of complications, rate of serological conversion, and local control at follow-up were derived. Fisher’s exact test and Mann–Whitney U test were used and Kaplan–Meier curve calculated.ResultsTechnical success was obtained in all 46 lymph nodes (100 %). There were no major complications. Thyroglobulin levels decreased from 8.40 ± 9.25 ng/ml before treatment to 2.73 ± 4.0 ng/ml after treatment (p = 0.011), with serological conversion in 11/24 (45.8 %) patients. Overall, local control was obtained in 40/46 (86.9 %) lymph nodes over 30 ± 11 month follow-up, with no residual disease seen at imaging in 19/24 (79.1 %) patients. Local control was achieved in 40/46 (86.9 %) lymph nodes at 1 year and in all of the 25 nodes (100 %) followed for 3 years. Estimated mean time to progression was 38.6 ± 2.7 m.ConclusionUltrasound-guided PLA is a feasible, safe, and effective therapy for the treatment of cervical lymph node metastases from papillary thyroid carcinoma.

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Lung Shunt Fraction prior to Yttrium-90 Radioembolization Predicts Survival in Patients with Neuroendocrine Liver Metastases: Single-Center Prospective Analysis

ObjectiveTo investigate survival outcomes following radioembolization with Yttrium-90 (Y90) for neuroendocrine tumor liver metastases (NETLMs). This study was designed to assess the efficacy of Y90 radioembolization and to evaluate lung shunt fraction (LSF) as a predictor for survival.MethodsA single-center, prospective study of 44 consecutive patients (median age: 58.5 years, 29.5 % male) diagnosed with pancreatic (52.3 %) or carcinoid (47.7 %) NETLMs from 2006 to 2012 who underwent Y90 radioembolization was performed. Patients’ baseline characteristics, including LSF and median overall survival (OS) from first Y90 radioembolization, were recorded and compared between patients with high (≥10 %) and low (<10 %) LSF. Baseline comparisons were performed using Fisher’s exact tests for categorical and Mann–Whitney U test for continuous variables. Survival was calculated using the Kaplan–Meier method. Univariate (Wilcoxon rank-sum test) and multivariate analyses (Cox Proportional Hazard Model) for risk factor analysis were performed.ResultsThere was no statistically significant difference in age, gender, race, tumor properties, or previous treatments between patients with high (n = 15) and low (n = 29) LSF. The median OS was 27.4 months (95 %CI 12.73–55.23), with 4.77 months (95 %CI 2.87–26.73) for high and 42.77 months (95 %CI 18.47–59.73) for low LSF (p = 0.003). Multivariate analysis identified high LSF (p = 0.001), total serum bilirubin >1.2 mg (p = 0.016), and lack of pretreatment with octreotide (p = 0.01) as independent prognostic factors for poorer survival. Tumor type and total radiation dose did not predict survival.ConclusionsLSF ≥10 %, elevated bilirubin levels, and lack of pretreatment with octreotide were found to be independent prognostic factors for poorer survival in patients with NETLMs.

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Aspirex Thrombectomy in Occluded Dialysis Access: A Retrospective Study

PurposeThis study is the first to present the outcomes of the Straub Aspirex device for the salvage of occluded renal dialysis access fistulae.Materials and MethodsThis is a retrospective study, using data from the Renal Unit and Radiology Department database. It included all the patients between 2010 and 2014 who underwent percutaneous mechanical thrombectomy (PMT) treated by JD. Aspirex is an over-the-wire, 6–10 French catheter within which is a rapidly rotating helix which draws thrombus into a window near the tip which it then macerates and removes. Access survival was assessed using the Kaplan–Meier method, and multi-variant analysis was performed using the Cox proportional hazards model. Significance was considered if p < 0.05.ResultsA total of 27 procedures were performed for 19 patients. 13 had autologous arterio-venous fistulae, and 14 had synthetic (PTFE) arterio-venous grafts. 15 were males, 4 females. 100 % of the patients successfully had a channel of thrombus removed. This resulted in an 81.5 % initial clinical success, with primary patency rates of 53.6, 44.3 and 33 % by days 30, 90 and 480, respectively, without significant difference of any analysed covariates. No major complication (pulmonary embolus, paradoxical cerebral infarction, limb ischaemia or significant haemorrhage) occurred.ConclusionAspirex has rates of patency and complication similar to other PMT devices. No covariant studied affected outcome.

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Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

PurposeTo estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.Materials and MethodsFrom March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34–94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan–Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.ResultsTechnical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6–224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0–132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child–Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).ConclusionPercutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting patient survival and stent patency, and stent patency showed statistically significant correlation with patient survival.

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The Relationship Between Neutrophil–Lymphocyte Ratio and Primary Patency of Percutaneous Transluminal Angioplasty in Hemodialysis Arteriovenous Fistula Stenosis When Using Conventional and Drug-Eluting Balloons

ObjectiveThe aim of this study is to investigate the potential association of neutrophil–lymphocyte ratio (NLR) between primary patency of percutaneous transluminal angioplasty (PTA) in hemodialysis arteriovenous fistula stenosis and type (Conventional and Drug-Eluting) of balloons used in PTA.Material-MethodThis retrospective study consists of 78 patients with significant arteriovenous fistulas stenosis who were treated with PTA by using Drug-Eluting Balloon (DEB) (n = 29) or Conventional Balloon (CB) (n = 49). NLR was calculated from preinterventional blood samples. All patients were classified into two groups. Group A; primary patency <12 months (43/78), Group B; primary patency ≥12 months (35/78). Cox regression analysis and Kaplan–Meier method were used to determine respectively independent factors affecting the primary patency and to compare the primary patency for the two balloon types.ResultsNLR ratio and balloon type of the two groups were significantly different (p = 0.002, p = 0.010). The cut-off value of NLR was 3.18 for determination of primary patency, with sensitivity of 81.4 % and specificity of 51.4 %. Primary patency rates between PTA with DEB and CB displayed statistically significant differences (p < 0.05). The cut-off value was 3.28 for determination of 12-month primary patency with the conventional balloon group; sensitivity was 81.8 % and specificity was 81.3 %. There was no statistical relation between NLR levels and the drug-eluting balloon group in 12-month primary patency (p = 0.927).ConclusionIncreased level of NLR may be a risk factor in the development of early AVF restenosis after successful PTA. Preferring Drug-Eluting Balloon at an increased level of NLR can be beneficial to prolong patency.

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Paclitaxel-Coated Balloons for the Treatment of Dysfunctional Dialysis Access. Results from a Single-Center, Retrospective Analysis

PurposeTo investigate the safety and effectiveness of lutonix paclitaxel-coated balloon (PCB) for the treatment of dysfunctional dialysis access.Materials and MethodsThis was a single-center, single-arm, retrospective analysis of 39 patients (23 male, 59 %) undergoing 61 interventions using 69 PCBs in a 20-month period. There was a balance between arteriovenous fistulae (AVF) and grafts (AVG) (20 AVFs, 19AVGs), and the majority of lesions were restenotic (25/39, 64.1 %). Mean balloon diameter used was 6.6 mm and length 73.4 mm. Primary outcome measure was target lesion primary patency (TLPP) at 6 months, while secondary outcome measures included factors affecting TLPP and major complications. As there were lesions treated more than once with PCB, authors also compared patency results after first and second PCB angioplasty.ResultsTLPP was 72.2 % at 6 months with a median patency of 260 days according to the Kaplan–Meier survival analysis. No major complications occurred. TLPP between AVFs and AVGs (311 vs. 237 days, respectively; p = 0.29) and de novo and restenotic lesions was similar (270.5 vs. 267.5 days, respectively; p = 0.50). In 14 cases, in which lesions were treated with two PCB angioplasties, a statistically significant difference in TLPP after the second treatment was noted (first intervention 179.5 days vs. second intervention 273.5 days; p = 0.032).ConclusionIn this retrospective analysis, Lutonix PCB proved to be safe and effective in treating restenosis in dysfunctional dialysis access with results comparable to the literature available. Larger studies are needed to prove abovementioned results.

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