Fabrizio Fanelli

Nitinol stents with polymer-free paclitaxel coating for lesions in the superficial femoral and popliteal arteries above the knee: twelve-month safety and effectiveness results from the Zilver PTX single-arm clinical study.

Purpose To report a prospective, single-arm, multicenter clinical study evaluating the Zilver PTX drug-eluting stent for treating the above-the-knee femoropopliteal segment (NCT01094678; http://www.clinicaltrials.gov ). Methods The Zilver PTX drug-eluting stent is a self-expanding nitinol stent with a polymer-free paclitaxel coating. Patients with symptomatic (Rutherford category 2–6) de novo or restenotic lesions (including in-stent stenosis) of the above-the-knee femoropopliteal segment were eligible for enrollment. Between April 2006 and June 2008, 787 patients (578 men; mean age 66.6±9.5 years) were enrolled at 30 international sites. Results Nine hundred lesions (24.3% restenotic lesions of which 59.4% were in-stent stenoses) were treated with 1722 Zilver PTX stents; the mean lesion length was 99.5±82.1 mm. The 12-month Kaplan-Meier estimates included an 89.0% event-free survival rate, an 86.2% primary patency rate, and a 90.5% rate of freedom from target lesion revascularization. There were no paclitaxel-related adverse events reported. The 12-month stent fracture rate was 1.5%. The ankle-brachial index, Rutherford score, and walking distance/speed scores significantly improved (p<0.001) from baseline to 12 months. Conclusions These results indicate that the Zilver PTX drug-eluting stent is safe for treatment of patients with de novo and restenotic lesions of the above-the-knee femoropopliteal segment. At 1 year, the overall anatomical and clinical effectiveness results suggest that this stent is a promising endovascular therapy.

New ePTFE/FEP-covered stent in the palliative treatment of malignant biliary obstruction

PURPOSE To determine the technical efficacy and safety of an expanded polytetrafluoroethylene and fluorinated ethylene propylene (ePTFE/FEP)-covered metallic stent in the management of malignant biliary obstruction and to evaluate its clinical efficacy by estimating stent patency and patient survival rates. MATERIALS AND METHODS Twenty-six patients with common bile duct stricture caused by malignant disease were treated by placement of 29 stents. The stent consists of an inner ePTFE/FEP lining and an outer supporting structure of nitinol wire. Multiple wire sections elevated from the external surface provide anchoring. Stents are available in two versions, with or without holes in the proximal stent lining. Holes should provide drainage of the cystic duct or biliary side branches when covered by the proximal stent end. Clinical evaluation and assessment of serum bilirubin and liver enzyme levels were done before stent placement and at 1, 3, 6, and 9 months. Average follow-up duration was 5.4 months (range, 5 d to 12.5 mo). RESULTS Placement was successful in all cases. The 30-day mortality rate was 11.5%. The survival rates were 40% and 15% at 6 and 12 months, respectively. Eighty-four percent of patients had adequate palliative drainage during their lifetime. The stent patency rates were 91%, 77%, and 77% at 3, 6, and 12 months, respectively. Four patients (16%) presented with stent occlusion and needed repeat intervention. No migration occurred. Complications other than stent occlusion occurred in five patients (19%); among these, acute cholecystitis was observed in three patients (12%). CONCLUSION Preliminary results suggest that placement of this ePTFE/FEP-covered stent is feasible and effective in achieving biliary drainage. The percentage of patients undergoing lifetime palliation and the midterm patency are promising. However, the incidence of acute cholecystitis is high. Treatment of a larger group of patients is mandatory to validate these long-term results.

Prospective Comparative Analysis of Colour-Doppler Ultrasound, Contrast-enhanced Ultrasound, Computed Tomography and Magnetic Resonance in Detecting Endoleak after Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVES To assess the accuracy of colour-Doppler ultrasound (CDUS), contrast-enhanced ultrasonography (CEUS), computed tomography angiography (CTA) and magnetic resonance angiography (MRA) in detecting endoleaks after endovascular abdominal aortic aneurysm repair (EVAR). DESIGN Prospective, observational study. MATERIALS AND METHODS From December 2007 to April 2009, 108 consecutive patients who underwent EVAR were evaluated with CDUS, CEUS, CTA and MRA as well as angiography, if further treatment was necessary. Sensitivity, specificity, accuracy and negative predictive value of ultrasound examinations were compared with CTA and MRA as the reference standards, or with angiography when available. RESULTS Twenty-four endoleaks (22%, type II: 22 cases, type III: two cases) were documented. Sensitivity and specificity of CDUS, CEUS, CTA, and MRA were 58% and 93%, 96% and 100%, 83% and 100% and 96% and 100% respectively. CEUS allowed better classification of endoleaks in 10, two and one patients compared with CDUS, CTA and MRA, respectively. CONCLUSIONS The accuracy of CEUS in detecting endoleaks after EVAR is markedly better than CDUS and is similar to CTA and MRA. CEUS seems to be a feasible tool in the long-term surveillance after EVAR, and it may better classify endoleaks missed by other imaging techniques.

Lower Limb Multilevel Treatment With Drug-Eluting Balloons: 6-Month Results From the DEBELLUM Randomized Trial:

Purpose To report 6-month results of the DEBELLUM (Drug-Eluting Balloon Evaluation for Lower Limb MUltilevel TreatMent) randomized trial to evaluate the efficacy of a drug-eluting balloon (DEB) to reduce restenosis after treatment of multilevel lower limb occlusive disease vs. a conventional angioplasty balloon (AB). Methods Between September 2010 and March 2011, 50 consecutive patients (37 men; mean age 66 ± 4 years) with 122 lesions (96 stenoses and 26 occlusions) of the femoropopliteal (92, 75.4%) or below-the-knee (BTK) arteries (30, 24.6%) were enrolled and randomly assigned to the DEB (25 patients with 57 lesions) or AB (25 patients with 65 lesions) group. Twenty patients presented multilevel lesions. Mean lesion length was 7.5 ± 3.5 cm. Thirty-one (62%) of the patients were Fontaine stage IIb, while 19 (38%) were stage III or IV. DEBs or ABs were used for dilation of de novo lesions or for postdilation after primary stenting (superficial femoral artery only). Patients requiring provisional stenting after angioplasty secondary to flow-limiting dissection or residual stenosis >50% were ineligible. Primary endpoint was late lumen loss at 6 months. Secondary endpoints were target lesion revascularization (TLR), amputation, and thrombosis. Results Late lumen loss was lower in the DEB group (0.5 ± 1.4 vs. 1.6 ± 1.7 mm, p<0.01). TLR was necessary in 6.1% of the DEB group vs. 23.6% of the AB group (p=0.02). Comparing the DEB to AB groups, the thrombosis rates were 3.0% vs. 5.2% (p=0.6), and the amputation rates were 3.0% vs. 7.9% (p=0.36). The binary restenosis rates were 9.1% (3/33 limbs) in the DEB group vs. 28.9% (11/38 limbs) in the control group (p=0.03). The anklebrachial index improved to a greater degree in the DEB group: 0.87 ± 0.22 vs. 0.70 ± 0.13 (p<0.05). The Fontaine stage improved in both groups but more so in patients treated with DEBs (p=0.04). Conclusion The DEBELLUM trial confirmed the ability of paclitaxel-eluting balloons to reduce restenosis vs. conventional balloons at 6 months after treatment of multilevel (femoropopliteal and BTK) arterial disease in patients affected by claudication and CLI. A lower TLR rate and better clinical outcomes appear to be associated with the use of DEBs regardless of stent placement.

Clinical efficacy of transjugular intrahepatic portosystemic shunt created with covered stents with different diameters: Results of a randomized controlled trial

BACKGROUND & AIMS The incidence of post-TIPS hepatic encephalopathy (HE) could be reduced by using stents with a small diameter. The aim of this study was to compare the incidence of HE and the clinical efficacy of TIPS created with 8- or 10-mm PTFE-covered stents. METHODS Consecutive cirrhotics submitted to TIPS for variceal bleeding or refractory ascites were randomized to receive a 8- or 10-mm covered stent. As recommended by our Ethical Committee, the trial was stopped after the inclusion of 45 patients. RESULTS The two groups were comparable for age, sex, etiology, and psychometric performance. After TIPS, the portosystemic pressure gradient was significantly higher in the 8-mm stent group (8.9+/-2.7 versus 6.5+/-2.7 mmHg; p=0.007). Consequently, the probability of remaining free of complications due to portal hypertension was significantly higher in the 10-mm than in the 8-mm stent group: 82.9% versus 41.9% at one year; log-rank test, p=0.002. In particular, the persistence of ascites with the need for repeated paracentesis was significantly more frequent in the patients treated with 8-mm stent diameter for refractory ascites (log-rank test, p=0.008). The probability of remaining free of HE was similar in both groups. Cumulative survival rate was similar in both groups. CONCLUSIONS The use of 8-mm diameter stents for TIPS leads to a significantly less efficient control of complications of portal hypertension. HE remains an unsolved major problem after TIPS.

Polytetrafluoroethylene-covered stent grafts for TIPS procedure: 1-year patency and clinical results.

OBJECTIVES:Polytetrafluoroethylene (PTFE)-covered stent grafts appear to have the potential to improve TIPS patency, but data available are few and controversial. The aim of this prospective nonrandomized trial was to assess TIPS safety and 1-yr patency with a new commercially available PTFE-covered stent graft in comparison with a group of historical controls treated with conventional stents.METHODS:Between July 1992 and December 1999, 87 consecutive cirrhotics underwent TIPS with conventional stents, while from January 2000 to November 2001, 32 consecutive cirrhotics were treated with PTFE-covered stent grafts. All patients were followed by the same medical team according to a prospective protocol for a diagnostic work-up and a surveillance strategy.RESULTS:The two groups were comparable for age, sex, etiology, and severity of cirrhosis. The 1-yr probability of remaining free of shunt dysfunction tended to be higher in the covered stent group: 76.3% (95% CI = 58.7–93.9%) versus 57.5% (95% CI = 46.6–68.4%); log rank test: p= 0.055. However, stenoses inside the stent were significantly higher in patients with bare stents (88% vs 17%), while stenoses at the hepatic or portal vein were more frequent in PTFE-covered stent-graft group (50%vs 9% and 33%vs 3%, respectively), (χ2= 15.42; df= 2.0; p= 0.0004). Stenoses inside the covered portion of the stent did not occur. One-year cumulative rebleeding, encephalopathy, and survival were similar.CONCLUSIONS:PTFE-covered stents are able to solve pseudointimal hyperplasia within the stent tract, but have a high incidence of hepatic or portal vein stenosis. Improvements in stent design and insertion techniques are necessary to fully achieve the potential benefit of this new device.

Pancreatic adenocarcinoma: combination of MR imaging, MR angiography and MR cholangiopancreatography for the diagnosis and assessment of resectability

Abstract. The purpose of this study was to determine the possibility of integrating MR cholangiopancreatography (MRCP) and MR angiography (MRA) to conventional MR images in the diagnosis and assessment of resectability of pancreatic adenocarcinoma. Twenty-three patients with pancreatic adenocarcinoma were prospectively examined with MR. Conventional MR images were acquired in all patients. Three-dimensional MRCP and MRA images were acquired in all patients with suspected biliary and vascular involvement. Acquisition time was less than 45 min in all cases. Images were independently evaluated by two radiologists, with final reading decided by consensus among readers. Diagnosis was confirmed with surgery in 16 patients and with percutaneous biopsy in 7. Concordance among readers was high with a kappa value of 0.83. Pancreatic adenocarcinoma was observed in all patients. Correct assessment of unresectability due to vascular involvement was found in 22 of 23 patients. Biliary obstruction was evident in 13 patients, involving the biliary and pancreatic ducts in 9 and the biliary ducts only in 4. Technical advances permit extensive use of MRI in the evaluation of abdominal pathologies. The combination of MR imaging, MRCP, and MRA can provide sufficient information for the diagnosis and assessment of resectability of pancreatic adenocarcinoma, which otherwise would require three different exams.

Multidetector–row CT angiography of renal artery stenosis in 50 consecutive patients: prospective interobserver comparison with DSA

Purpose.The purpose of this study was to establish the diagnostic value of multidetector–row computed tomography (MDCT) angiography compared with digital subtraction angiography (DSA) for detection and quantification of both main and accessory renal artery stenosis in patients with secondary hypertension.Materials and methods.Fifty consecutive patients scheduled for DSA were considered candidates for MDCT angiography. In all patients, MDCT angiography of the abdominal aorta was performed before DSA. For the purpose of interpretation, the arteries were separately interpreted either with DSA or MDCT angiography in order to provide qualitative and quantitative information. For qualitative evaluation, one experienced reader graded the opacification of renal arteries as excellent, good or poor; for quantitative evaluation, MDCT and DSA were independently evaluated for the number of renal arteries and the presence, location and degree of stenosis in random order by three readers. On the basis of consensus readings, calculations of sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) for detection of degree of stenosis were made by using DSA findings as the standard of reference. Interobserver variability was also assessed.Results.With regard to qualitative analysis, arterial enhancement was considered excellent in 39 patients and good in 11. For quantitative analysis, 73 arteries were classified as normal with DSA. Although 72 of these were also classified as normal with CT angiography, one was overestimated by one grade; at DSA, 16 arteries were classified as moderately stenotic; in two arteries, there was an overestimation of one grade. Perfect correlation was achieved for the diagnosis of occlusion. In two patients, all three readers detected multiple severe stenoses on both modalities, with a “string–of–beads” appearance typical of fibromuscular dysplasia. Accessory arteries were correctly identified as such by all three readers on either DSA or MDCT. Levels of sensitivity, specificity and accuracy regarding degree of stenosis were 100%, 98.6% and 96.9%, respectively, with PPV and NPV of 97.6% and 100%, respectively. When we considered significant arterial stenosis (50%–100% luminal narrowing), sensitivity, specificity and accuracy were 100%, 97.3% and 97.8%, respectively, with a PPV and NPV of 98.2% and 97.8%, respectively. For all observers, interobserver agreement was almost perfect (k=0.81–1) for both MDCT and DSA, with a k value between 0.82 and 0.95.Conclusions.MDCT angiography is very accurate and robust, even for the assessment of renal artery stenosis, and has the potential to become a viable substitute, in most cases, for diagnostic catheter–based DSA.

Management of Refractory Hepatic Encephalopathy After Insertion of TIPS: Long-Term Results of Shunt Reduction With Hourglass-Shaped Balloon-Expandable Stent-Graft

OBJECTIVE The purpose of this study was to review the use of an hourglass-shaped expanded polytetrafluoroethylene (ePTFE) stent-graft to reduce transjugular intrahepatic portosystemic shunts in patients with hepatic encephalopathy refractory to conventional medical therapy. MATERIALS AND METHODS From January 2000 through December 2008, 189 transjugular intrahepatic portosystemic shunt procedures were performed with self-expanding stent-grafts. After a mean period of 43.4 +/- 57 weeks, hepatic encephalopathy developed in 12 patients and did not respond to conventional medical therapy with lactulose, nonabsorbable antibiotics, and a protein-restricted diet. In all cases, shunt reduction was performed with an hourglass-shaped balloon-expandable ePTFE stent-graft inserted into the original shunt. RESULTS Technically successful shunt reduction with an immediate increase in portosystemic gradient was achieved in all patients. Symptoms of hepatic encephalopathy disappeared a mean of 22.3 hours (range, 18-26 hours) after the procedure. After a mean follow-up period of 73.9 +/- 61.88 weeks, no recurrence of hepatic encephalopathy was found. One patient (8.3%) needed dilation of the hourglass-shaped stent-graft after 37 weeks because of recurrence of ascites. At the end of the study, five patients (41.6%) were alive in good clinical condition. Four patients (33.3%) died of cardiovascular failure 1, 2, 24, and 96 weeks after the corrective procedure. Eight months after the reduction procedure, one patient (8.3%) underwent orthotopic liver transplantation, which resulted in clinical improvement. Two patients (16.6%) were lost to follow-up 15.6 and 46.8 weeks after the procedure. CONCLUSION Shunt reduction with an hourglass-shaped ePTFE balloon-expandable stent-graft seems effective in reducing shunt flow and rapidly improving the patients clinical condition. With this technique, shunt diameter can be modified on the basis of the patients clinical condition.

Peripheral Arterial Occlusive Disease: Diagnostic Performance and Effect on Therapeutic Management of 64-Section CT Angiography

PURPOSE To evaluate the diagnostic performance and effect on therapeutic management of 64-section computed tomographic (CT) angiography in the assessment of steno-occlusive disease in patients with peripheral arterial disease (PAD), with conventional digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS The study protocol was approved by the institutional review board, and written informed consent was obtained from all patients. A total of 212 patients with symptomatic PAD underwent CT angiography and subsequent DSA. For stenosis analysis (≥ 70% stenosis), the arterial bed was divided into 35 segments and evaluated by three readers. Interobserver agreement was determined with generalized κ statistics. Accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated. In addition, according to the TransAtlantic Inter-Society Consensus (TASC) Document on Management of Peripheral Arterial Disease guidelines, treatment recommendations based on CT angiographic and DSA findings were compared. McNemar test was used to prove significant differences between CT angiographic and DSA findings. RESULTS A total of 7420 arterial segments were evaluated, with excellent agreement between readers (κ ≥ 0.928). On a segmental basis, both sensitivity and specificity for stenosis of 70% or more were at least 96% (3072 of 3113 segments and 4141 of 4279 segments, respectively), with an accuracy of 98% (7213 of 7392 segments), a PPV of 96% (3072 of 3187 segments), an NPV of 99% (3141 of 3187 segments), a PLR of 36.7, and an NLR of 0.013. There was no significant difference between CT angiographic and DSA findings (P = .62-.87). In accordance with TASC II guidelines, 49 patients were referred for conservative treatment, 87 underwent endovascular procedures, 38 underwent surgery, and 17 received hybrid treatment. Therapy recommendations based on CT angiographic findings alone were identical to those based on DSA findings in all but one patient. CONCLUSION The diagnostic performance of 64-section CT angiography is excellent in patients with clinical symptoms of PAD. The results can be used to effectively guide therapeutic decision making in these patients.