Uncovered Stents Research Articles

Impact of low tissue backscattering by optical coherence tomography on endothelial function after drug-eluting stent implantation.

This study evaluated the impact of optical coherence tomography (OCT)-derived low-backscattered tissue on mid-term coronary endothelial function after drug-eluting stent (DES) implantation. Although OCT enables detailed in vivo evaluation of neointimal tissue characterization after DES implantation, its association with physiological vascular healing response is unclear. Thirty-three stable angina pectoris patients underwent OCT examination and endothelial function testing with intracoronary infusion of incremental doses of acetylcholine 8-month after DES implantation in a single lesion of the left anterior descending artery. Neointimal tissue was classified into two patterns based on the predominant OCT light backscatter: high backscatter and low backscatter. Although the presence of uncovered or malapposed stent strut was not associated with the degree of vasoconstriction, the degree of vasoconstriction was significantly greater in the DES with low-backscattered neointima than in the DES without low-backscattered neointima (- 32.1 ± 25.7 vs. - 4.1 ± 20.1%, p = 0.003). Moreover, there was an inverse linear relationship between low backscatter tissue index and degree of vasoconstriction after acetylcholine infusion (r = 0.50 and p = 0.003). The endothelium-dependent vasomotor response after 8-month of DES was impaired in patients with low neointimal tissue backscatter on OCT imaging. OCT assessment of low-backscattered tissue may be used as surrogate markers for impairment of endothelial function after DES.

External Iliac Occlusion Does Not Preclude Endovascular Management of Aortoiliac Disease–Technique and Evolution of Therapy

Controversy remains over how to best manage chronic total occlusions of the aortoiliac (AI) system. Uncovered stents are the traditional choice but offer less durability in theory with the risk of stent ingrowth. External iliac artery (EIA) occlusions are challenging due to access difficulty. We performed a retrospective study of patients who had undergone endovascular AI intervention between December, 2014 and March, 2017 for Trans-Atlantic Inter-Society Consensus D lesions. The primary study end point was overall survival. Secondary end points included primary assisted or secondary patency and procedural complications. Twenty-one patients were identified in the 22-month period that underwent recanalization of at least 1 iliac segment, using Atrium iCAST in the aorta and common iliac segments and/or Viabahn stents in the external iliac arteries. Overall AI patency was 100% (mean 6.8months). Six AI bifurcation advancements were performed (primary patency 100%, mean 8months). Eight patients with EIA occlusion underwent total percutaneous revascularization (primary patency 88%, secondary patency 100% mean 6months). Five outflow procedures were performed concurrent to the AI recanalization. Two patients (15.4%) died of cardiovascular events. No access site complications were observed in the cohort. AI occlusive disease remains a surgical challenge. Although uncovered stents are a common therapy for revascularization of this vascular bed, our experience with balloon-expanding and self-expanding covered stents suggests they may be used to good effect with minimal complications in the intermediate term.

Neoatherosclerosis in Patients With Coronary Stent Thrombosis: Findings From Optical Coherence Tomography Imaging (A Report of the PRESTIGE Consortium)

ObjectivesThe purpose of this study was to assess neoatherosclerosis in a registry of prospectively enrolled patients presenting with stent thrombosis using optical coherence tomography. BackgroundIn-stent neoatherosclerosis was recently identified as a novel disease manifestation of atherosclerosis after coronary stent implantation. MethodsAngiography and intravascular optical coherence tomography were used to investigate etiologic factors of neoatherosclerosis in patients presenting with stent thrombosis >1 year after implantation (very late stent thrombosis [VLST]). Clinical data were collected according to a standardized protocol. Optical coherence tomographic acquisitions were analyzed in a core laboratory. Cox regression analysis was performed to identify factors associated with the formation of neoatherosclerosis and plaque rupture as a function of time. ResultsOptical coherence tomography was performed in 134 patients presenting with VLST. A total of 58 lesions in 58 patients with neoatherosclerosis were compared with 76 lesions in 76 patients without neoatherosclerosis. Baseline characteristics were similar between groups. In-stent plaque rupture was the most frequent cause (31%) in all patients presenting with VLST. In patients with neoatherosclerosis, in-stent plaque rupture was identified as the cause of VLST in 40 cases (69%), whereas uncovered stent struts (n = 22 [29%]) was the most frequent cause in patients without neoatherosclerosis. Macrophage infiltration was significantly more frequent in optical coherence tomographic frames with plaque rupture compared with those without (50.2% vs. 22.2%; p < 0.0001), whereas calcification was more often observed in frames without plaque rupture (17.2% vs. 4%; p < 0.0001). Implantation of a drug-eluting stent was significantly associated with the formation of neoatherosclerosis (p = 0.02), whereas previous myocardial infarction on index percutaneous coronary intervention was identified as a significant risk factor for plaque rupture in patients with neoatherosclerosis (p = 0.003). No significant difference was observed in thrombus composition between patients with or without neoatherosclerosis. ConclusionsNeoatherosclerosis was frequently observed in patients with VLST. Implantation of a drug-eluting stent was significantly associated with neoatherosclerosis formation. In-stent plaque rupture was the prevailing pathological mechanism and often occurred in patients with neoatherosclerosis and previous myocardial infarction at index percutaneous coronary intervention. Increased macrophage infiltration heralded plaque vulnerability in our study and might serve as an important indicator.

Percutaneous Antegrade Colonic Stent Insertion Using a Proximal Trans-peritoneal Colopexy Technique

Conventionally, colonic stents are inserted with a retrograde trans-anal approach-however, stenting of right-sided or proximal transverse colon lesions may pose a challenge due to tortuosity or long distances. We report three successful cases of percutaneous antegrade colonic stenting in patients using a proximal trans-peritoneal colopexy technique. Three patients underwent a proximal trans-peritoneal colopexy technique for antegrade colonic stent placement. The patients included three males, ages 89, 92 and 55, who were unsuitable for conventional methods. All patients had a colopexy with the aid of three gastropexy sutures performed under CT or fluoroscopic guidance and subsequent colonic access, followed by the crossing lesion and subsequent deployment of an uncovered colonic stent. A 10-Fr pigtail catheter was exchanged for the sheath, capped and left in place along with the colopexy suture anchors. Percutaneous antegrade colonic stent placement was technically successful in all patients with no complications. Follow-up at 10days, a tubogram confirmed stent patency. The pigtail drain and suture anchors were subsequently removed. Antegrade colonic stenting with the use of a three point colopexy is a straightforward well-tolerated procedure and is a useful technique in a cohort of patients in whom conventional stenting has failed/is unsuitable. Additionally, we believe we have reported the first two cases involving transverse colon access for stenting.

Internal biliary drainage for isolated posterior segmental biliary obstruction: a case report

BackgroundBiliary system anatomical abnormalities can be preoperatively detected on magnetic resonance imaging; therefore, some presume that the number of bile duct injuries should decline. However, once a bile duct injury occurs, repair may be difficult. There are various ways to repair bile duct injuries, but successful repair may be exceptionally difficult.Case presentationA 72-year-old Japanese man underwent a pancreaticoduodenectomy due to a diagnosis of middle bile duct cancer. We had a complication of an isolated posterior segmental biliary obstruction when pancreaticoduodenectomy was performed. We conducted a drip infusion cholecystocholangiography-computed tomography test to determine the positional relationship between his bile duct and elevated jejunum. To secure the bile duct we punctured the bile duct under computed tomography guidance, and the hepaticojejunal anastomosis site was visualized by inserting an endoscope. We vibrated the bile duct wall by inserting a guide wire through a puncture needle and verified the vibrations with the endoscope. We observed a partially compressed elevated jejunal wall upon guide wire insertion; therefore, we could verify a puncture needle penetration into the elevated jejunum by endoscope on insertion. We also successfully inserted an 8.5-Fr pigtail catheter into the elevated jejunum. We removed all drains after percutaneously inserting an uncovered metallic stent. Our patient’s subsequent clinical course was unremarkable. He visits our institution as an out-patient and has had no stent occlusion even after 6 months.ConclusionsWhen repairing bile duct injuries, it is important to accurately determine the positional relationships between the injured bile duct and the surrounding organs.

Su1362 LONG-TERM OUTCOMES OF ENDOSCOPIC ULTRASOUND-GUIDED GASTROENTEROSTOMY USING LUMEN-APPOSING METAL STENTS FOR GASTRIC OUTLET OBSTRUCTION: A 4-YEAR COHORT

EUS-guided gastroenterostomy (EUS-GE) using lumen-apposing metal stents (LAMS) is a promising procedure for the treatment of patients with gastric outlet obstruction (GOO). Reported short-term outcomes on EUS-GE include longer patency compared to enteral stents and less peri-procedural adverse events (AE) compared to surgical GE. However, little is known regarding mid- and long-term outcomes. To study long-term favorable outcomes after EUS-GE defined as a composite of technical and clinical success without occurrence of AEs or need for re-interventions for recurrent GOO at 6 and 12 months post-procedure. Patients who underwent EUS-GE for both benign and malignant GOO between 3/2014 and 10/2017 were included. Technical success is defined as successful placement of LAMS to create GE. Clinical success is defined as the ability to tolerate at least a full fluid diet. AE, re-interventions and outcomes after re-interventions were recorded. There were 37 patients with GOO, of which 30 had malignant GOO (81.1%), 18 were males (48.6%), with a median age of 63 years (IQR 53-71). Patients had a median follow-up time of 231 days (IQR 61-471). Median procedural time was 50 minutes (IQR 35.5-78). Those with balloon-assisted EUS-GE technique (n=10, 27%) required longer procedural time compared to those with direct EUS-guided technique (median 92 vs 41 minutes, p= 0.02). Technical success was achieved in 35/37 patients (94.6%). Clinical success was achieved in 30/35 patients (85.7%). Re-interventions were required in 5/30 patients (16.7%) who initially achieved clinical success. Technical failure, clinical failure, re-interventions, and AE are detailed in Table 1. There were 5 LAMS misdeployments (2 patients with technical failure and defects closed by over-the-scope clips; 3 patients had successful rescue EUS-GE during the same session). Among 37 patients who underwent attempted EUS-GE, there was one AE (2.7%) described as gastrocolonic fistula due to delayed LAMS migration. The majority of patients experienced short-term favorable outcomes (25/37 patients, 67.6%), and this remained at 6 months (82.3%) and 1 year (77.8%) (Figure 1). After EUS-GE, GOO score improved from baseline median GOO score of 0 (IQR 0-1) to 3 (IQR 2-4) (P < 0.0001). There were 14 deaths (none related to EUS-GE), all with malignant GOO, with a median time from index EUS-GE of 49.5 days (IQR 29-157). On univariate analysis, there was no particular patient factor, etiology of GOO, site of obstruction or procedural factor that was associated with favorable outcome at 6 months and 1 year. EUS-GE using LAMS for GOO resulted in favorable outcomes in two-thirds of patients at 6 and 12 months after index EUS-GE. Stent misdeployment may occur but can be salvaged in the majority of cases.Tabled 1Table 1: Patients with technical failure, clinical failure, and/or recurrence of gastric outlet obstruction requiring re-interventions.Age/genderEtiology of GOOSite of obstructionFollow-up time (days)InterventionOutcomes of re-interventionsPrimary technical failures81/maleGastric adenocarcinomaEfferent limb536Extent from the stomach to the efferent limb was >10 mm. Over-the-scope clip placed to gastric defect and an uncovered metal stent placed in the efferent limb.Deceased at POD 536 with no reintervention.66/femaleSevere peptic strictureSecond part of the duodenum47815mm balloon dilation of the stricture.No recurrence.Clinical failure with persistence of GOO symptoms after index EUS-GE72/maleDuodenal adenocarcinomaSecond part of the duodenum28Symptoms persisted. POD 19 with new multiple downstream jejunal mass. No interventions performed.Deceased on POD 28 from malignancy.18/femaleSMA syndromeThird part of the duodenum177Symptoms persisted. Received an endoscopic gastrojejunal tube placement on POD 99 after EUS-GE.Dependent on tube feeding.53/femaleMetastatic colon cancerThird part of the duodenum45Symptoms persisted. CT showed no obstruction. No further intervention.Deceased on POD 45 from malignancy.61/maleGallbladder cancerDuodenal sweep1100Symptoms persisted. Improved with endoscopic PEGJ on POD 170.Dependent on tube feeding.84/femalePancreatic ductal adenocarcinomaThird part of the duodenum130Symptoms persisted. Two EGDs on POD 14 and POD 30 showed patent LAMS.Deceased on POD 130 from malignancy.Reinterventions for recurrence of GOO symptoms78/maleChronic peptic duodenitisDuodenal bulb231POD17: Endoscopic placement of gastrostomy for palliation.No improvement. Bacteremia due to parenteral nutrition. Deceased POD 231.68/maleCholangiocarcinomaSecond part of the duodenum144POD 23: Disimpaction of food debris and a placement of a fully covered esophageal metal stent via the lumen of the LAMS for stent occlusion. The coaxial esophageal stent was removed on POD 29.Improved GOOS from 1 to 4. Deceased POD 144.53/maleSMA syndromeThird part of the duodenum1101POD 14: Unsuccessful endoscopic gastrostomy placement.Later diagnosed with rectal cancer. Dependent on parenteral nutrition.62/femaleMetastatic ovarian cancerPrepyloric area547POD 158: LAMS was removed due to clinical improvement. Symptoms recurred requiring fluoroscopic-guided gastrojejunal tube placement on POD 401.Dependent on tube feeding.Adverse event based on ASGE lexicon criteria68/femalePancreatic ductal adenocarcinomaDuodenal bulb843GOO symptoms improved after index EUS-GE. POD 317: CT showed distal migration of LAMS causing gastrocolonic fistula. Treatment for asymptomatic gastrocolonic fistula included stent removal, APC and endosuturing. Graded as moderate severity of AE based on lexicon ASGE criteria.No recurrence of GOO throughout POD 843. Open table in a new tab

Mo1094 THE UTILITY OF ENDOSCOPIC OVERSTITCH FOR THE PREVENTION OF STENT MIGRATION IN THE UPPER GASTROINTESTINAL TRACT

Endoscopic placement of fully covered self-expandable metal stents (FCSEMS) is commonly used for treatment of benign and malignant conditions such as strictures, leaks or perforations. Stents migration has been reported to exceed 50%. Endoscopic overstitch is a new device mounted over the tip of the double channel endoscope and is used for suture fixation of to prevent migration. The aim of this study is to determine if this technique reduce stent migration in the upper gastrointestinal tract with different indications. This is a retrospective chart review of patients who underwent endoscopic luminal stent placement with and without suturing in the period between March 2014 and August 2017 at our academic medical center. We extracted data for demographics, indications of procedure, type of stent, location of stent, number of sutures, migration of stent despite suturing, and follow up. Nonparametric tests and Fisher exact test were used for statistical analysis. Sixty-seven patients with stent-placement were included in the analysis. Twenty-eight (42%) of the placed stents had endoscopic suture fixation. Indications included both malignancy (50% sutured stents vs 41% non-sutured stents) and complications of benign diseases (50% sutured stents vs 49% non-sutured stents). The median follow up after stent placement was 6 weeks. The majority of stents type was FCSEMS, 26/28 (93%) in sutured stent compared to 32/39(82%) in non-sutured. Only 1/28 (4%) sutured stent had migrated compared to 11/39 (28%) in non-sutured stent group (p=0.01), odds ratio was 0.094 (CI 0.011-0.78). The only stent migration in the sutured stent group was a gastric stent after sleeve gastrectomy with leakage. There were no significant complications on the sutured stents group. Evaluation for complications included chest pain, laceration, perforation, and bleeding. Subset analysis of esophageal stents showed 7/17(41%) migration in non-sutured stents compared to none in 18 (0/18) sutured stents (p=0.003). Endoscopic overstitch of luminal FCSEMS appears to be precisely effective and safe in preventing stent migration in the upper gastrointestinal tract.Tabled 1Sutured stentNon-sutured stentpSample size “n” (%)28 (42%)39 (58%)Not applicableMale gender (%)50%51%p>0.05Median age (years)6059p>0.05Malignancy “n” (%)14 (50%)16 (41%)p>0.05Benign indications (stricture, leak, perforation, fistula) “n” (%)14 (50%)23 (59%)p>0.05Esophageal cases “n” (%)18 (64%)17 (44%)p>0.05Total Migration “n” (%)1 (4%)11 (28%)p=0.01Migration in the esophageal subgroup “n” (%)0/18 (0%)7/17 (41%)p=0.003Other complications (chest pain, bleeding, laceration, perforation)NoneNoneNot applicableFCSEMSa “n” (%)26 (93%)32 (82%)p>0.05PCSEMSb “n” (%)0 (0%)1 (3%)p>0.05UCSEMSc “n” (%)2 (7%)6 (15%)p>0.05a Fully covered self-expandable metal stents. b Partially covered self-expandable metal stents. c Un-covered self-expandable metal stents Open table in a new tab

Evaluación del efecto sinérgico de la metformina y los inhibidores mTOR sobre la endotelización de los stents farmacoactivos en pacientes diabéticos

Introduction and objectivesRecent animal studies have shown metformin (MF) to impair endothelialization of drug-eluting stents (DES). The aim of this study was to evaluate the effect of MF on the healing of DES in human coronary arteries of patients with diabetes mellitus by optical coherence tomography (OCT). MethodsThe RESERVOIR trial randomized 116 lesions in 112 patients with diabetes mellitus to amphilimus- or everolimus-eluting stents and included mandatory OCT at 9 months of follow-up. Patients were divided in 3 groups according to the glucose-lowering agents received: a) no MF; b) MF in noninsulin treated patients, and c) MF in insulin-treated patients. The primary safety endpoint was the rate of uncovered stents. ResultsSeventeen patients with 19 lesions did not receive MF, whereas MF was administered to 53 noninsulin treated patients (54 lesions) and 28 insulin-treated patients (28 lesions). Baseline characteristics were comparable, although noninsulin treated patients who received MF had better glycemic control (P < .01). By OCT, rates of uncovered struts were comparable between groups (3.07±4.80% vs 2.23±4.73% vs 3.43±6.69%, respectively; P = .48). Multivariate models confirmed that MF had no effect on the healing of DES (OR, 1.49, 95%CI, 0.71-3.08; P = .29). Similarly, quantitative angiography showed no effect of MF on late lumen loss, whereas patients treated with exogenous insulin had greater late lumen loss (P = .02). ConclusionsMetformin use does not impair endothelial healing of DES in patients with both insulin- and noninsulin-treated diabetes mellitus. According to these results, MF should not be discouraged in these patients.Full English text available from: www.revespcardiol.org/en

Covered versus uncovered self-expandable metal stent for palliation of primary malignant extrahepatic biliary strictures: a randomized multicenter study

Self-expandable metal stents (SEMSs) are used to relieve malignant biliary obstructions. We aimed to compare stent patency, the adverse events rate, and overall survival of covered versus uncovered self-conformable metal stents in patients with primary malignant extrahepatic biliary strictures, not eligible for surgery. This is a multicenter randomized trial analyzing 158 patients with inoperable distal malignant biliary obstruction conducted in 5 Italian referral centers between December 2014 and October 2016. Seventy-eight patients were randomized to receive a fully covered SEMS (FCSEMS), and 80 patients received uncovered SEMSs (USEMSs). Data from 148 (72 FCSEMSs and 76 USEMSs) of 158 patients were analyzed. Median time of stent patency was lower for FCSEMSs (240 days vs 541 days for USEMSs; P= .031). Adverse events occurred with 19 FCSEMSs (26.4%) and 10 USEMSs (13.2%); P= .061. The main causes of FCSEMS dysfunction were migration (7% vs 0% in the USEMS group) and early occlusion mainly because of sludge or overgrowth; late stent occlusion because of tumor ingrowth occurred in 13.2% of patients in the USEMS group. There were no significant differences either in levels of conjugated bilirubin improvement or in overall survival between the FCSEMS and USEMS groups. Median survival was 134 days in the FCSEMS group and 112 days in the USEMS group (P= .23). The number of stent-related adverse events was higher, although not significantly, among patients in the FCSEMS group. FCSEMSs had a significantly higher rate of migration than USEMSs, and stent occlusion occurred earlier. A significant difference in the patency rate was observed in favor of the USEMS group. (Clinical trial registration number: NCT02102984.).

From the Editor’s desk....: May 2018

From the Editor’s desk....: May 2018

Abstract No. 636 A large-bore uncovered metallic stent for the treatment of malignant superior vena cava syndrome

To investigate the safety and efficacy of large-bore uncovered metallic stent placement in patients with malignant superior vena cava (SVC) syndrome. Between August 2015 and December 2016, 27 consecutive patients (24 men and 3 women; mean age, 64.3 years; range, 52-80 years) with malignant SVC syndrome were retrospectively reviewed. All patients were treated with a large-bore uncovered metallic stent (20-30 mm in diameter). The size of stent was chosen based on the diameter of 15-25% larger than the SVC. The mean diameter of SVC and brachiocephalic vein (BCV) were 18.3 mm and 14 mm, respectively. Stent placement was technically successful in all 27 patients. The mean diameter of the stent was 24 mm. Any overstretching nor overdistension of SVC and BCV was not observed. There were no major complications. The pressure gradient, which was 18.9 ± 8.0 mm Hg before stent placement, dropped significantly to 4.3 ± 3.0 mm Hg after stent placement (p<0.001). Of the 25 patients symptomatic prior to stent placement, 23 (92%) experienced complete symptomatic relief 1-6 days after stent placement. The median patient survival and stent patency time were 116 days 116 days (95% confidence interval [CI], 80-150 days) and 116 days (95% CI, 77-155 days), respectively. Three (11%) of the 27 patients presented with stent dysfunction due to tumor ingrowth (n = 1) and intrastent thrombosis (n = 2). Large-bore uncovered metallic stent placement appeared to be a safe and effective method for treating malignant SVC syndrome.

Minimally Invasive Interventional Management of Gastric Outlet Obstructions

AbstractGastric outlet obstruction (GOO) is a clinical consequence of any disease that produces intrinsic or extrinsic obstruction of the pyloric channel or duodenum. The most common symptoms of GOO include nausea, vomiting, abdominal pain, and weight loss. Traditionally, surgery is regarded as the standard treatment modality. However, with the development of mini-invasive technologies, fluoroscopic or endoscopic stenting and balloon dilatation have become the mainstream of the therapies. The initial recommended treatment for malignant GOO is self-expanding metal stent placement. The stent can be classified into covered and uncovered stent according to whether it is coated with a membrane. Covered stent seems to have longer stent patency, while uncovered stent has the advantage of a lower migration rate. Regarding the etiology of benign GOO, peptic ulcer disease and corrosive injury are the two main reasons. Balloon dilatation is a simple and convenient way to treat the benign GOO. Stent placement has recently been reported for the treatment of benign GOO; however, it needs further more studies to verify its effect. This article presents a concise review of current fluoroscopic or endoscopic stenting practice for malignant GOO and balloon dilatation or stenting for benign GOO.

Abstract No. 567 Transnasal and transgastric snare technique for the placement of retrograde primary jejunostomy tubes

To report technical success and clinical outcomes of the transnasal and transgastric snare techniques for placement of retrograde primary jejunostomy tubes. 6 female patients underwent the retrograde snare technique for the placement of a primary jejunostomy tube. Mean age was 54.5 years (range, 25-82 years). Patients presented with Roux-en-Y gastric bypass (n = 2), sleeve gastrectomy (n = 1), esophagectomy (n = 1), intra-thoracic stomach (n = 1), and gastroparesis (n = 1). Patients had targeting devices placed via either a transnasal (n = 5) or transgastric (n = 1) approach. Loop snare devices were used as a target in 5 patients and an uncovered stent in 1. Ultrasound and fluoroscopy were used to confirm the targeting device was within a superficial bowel loop in 4 patients, and cone-beam CT and fluoroscopy alone in 1 patient each. All snares and the stent were punctured with a styleted needle and used to capture a wire thereby obtaining through-and-through access for subsequent tract dilatation and placement of a primary retrograde jejunostomy. All (n = 6) transnasal and transgastric snare technique retrograde primary jejunostomy tube placements were technically successful. All tubes were 16 French MIC jejunostomy tubes (Halyard Health; Alpharetta, Georgia). 1 patient had abdominal pain on postoperative day 1 and couldn’t begin feeds until postoperative day 3. 1 patient’s tube was too long and extended above the gastroesophageal junction resulting in aspiration, requiring repositioning 4 days later. The remaining 4 patients were able to begin tube feeds on postoperative day 1. 1 patient’s tube hub cracked 6 weeks after placement and required exchange which was uneventful. The patient who underwent transgastric approach for placement of retrograde jejunostomy had no complications related to the removal of the transgastric catheter used for snare placement after the procedure. One patient died 2 weeks after tube placement secondary to aspiration pneumonitis. The remaining 5 patients had no issues with their tubes at average 41 days of follow-up. The transnasal and transgastric snare technique is a feasible and simple technique for the placement of retrograde primary jejunostomy.

Endovascular Iliocaval Stent Reconstruction for Iliocaval Thrombosis: A Multi-Institutional International Practice Pattern Survey

Limited guidelines for the treatment and management of acute and chronic iliocaval thrombosis are published in the literature. The purpose of this report is to present global iliocaval stent reconstruction practices by interventionalists. A 45-question survey focusing on iliocaval stent reconstruction evaluation was distributed through the Open Forum and Venous Disease Service Line of the Society of Interventional Radiology Connect website from June 20, 2017 until September 7, 2017 and the Cardiovascular and Interventional Radiological Society of Europe electronic newsletter on August 11,2017. One hundred seven complete responses were received from interventional radiologists in the United States, 2 from South America, and 2 from Central America. 92.5% performed iliocaval reconstruction, and 79.8% performed the procedure for both acute and chronic iliocaval thrombosis. 82.8% completed a standardized physician assessment tool, and 91.9% obtained computed tomography (CT) venography before the procedure. 64.6% used intravascular ultrasound to guide reconstruction. 41.4% found blunt recanalization successful for >75% of patients. 63.6% used sharp recanalization for <25% of patients. 97.0% and 90.9% used uncovered and self-expanding stents, respectively. Wallstents were used most commonly. Most common stent diameters were 24-mm in the inferior vena cava, 14-mm in the common iliac vein, and 12-mm in the external iliac vein. 48.5% and 21.2% prescribed 2 and 3 anticoagulants after stent placement, respectively. 62.6% found iliocaval reconstruction provided symptomatic clinical improvement for iliocaval thrombosis in >75% of patients. 72.7% estimated their 1-year primary stent patency to be >75%. Iliocaval reconstruction is performed by many interventionalists; however, there are global inconsistencies in practices, suggesting a need for further research and guideline development.

Covered duodenal self-expandable metal stents prolong biliary stent patency in double stenting: The largest series of bilioduodenal obstruction.

Endoscopic biliary and duodenal stenting (DS; double stenting) is widely accepted as a palliation therapy for malignant bilioduodenal obstruction. The aim of the current study was to investigate the patency and adverse events of duodenal and biliary stents in patients with DS. Patients who underwent DS from April 2004 to March 2017 were analyzed retrospectively with regard to clinical outcomes and predictive factors of recurrent biliary and duodenal obstruction (recurrent biliary obstruction [RBO] and recurrent duodenal obstruction [RDO]). A total of 109 consecutive patients was enrolled. Technical success of DS was achieved in 108 patients (99.1%). Symptoms due to biliary and duodenal obstruction were improved in 89 patients (81.7%). RBO occurred in 25 patients (22.9%) and RDO in 13 (11.9%). The median times to RBO and RDO from DS were 87 and 76days, respectively. Placement of a duodenal uncovered self-expandable metal stent (U-SEMS) was significantly associated with RBO in the multivariable analysis (P=0.007). Time to RBO was significantly longer in the duodenal covered self-expandable metal stent group than in the U-SEMS group (P=0.003). No predictive factors of RDO were detected, and duodenal stent type was not associated with the time to RDO (P=0.724). Double stenting was safe and effective for malignant bilioduodenal obstruction. Duodenal U-SEMS is a risk factor for RBO. The covered self-expandable metal stent is the preferred type of duodenal SEMS in patients with DS (Clinical trial registration number: UMIN000027606).

Mobilization of progenitor cells and assessment of vessel healing after second generation drug-eluting stenting by optical coherence tomography

BackgroundBone marrow-derived progenitor cells likely contribute to both endothelial- and smooth muscle cell-dependent healing responses in stent-injured vessel sites. This study aimed to assess mobilization of progenitor cells and vessel healing after zotarolimus-eluting (ZES) and everolimus-eluting (EES) stents. Methods and resultsIn 63 patients undergoing coronary stent implantation, we measured circulating CD34+CD133+CD45low cells and serum levels of biomarkers relevant to stem cell mobilization. In 31 patients of them, we assessed vessel healing within the stented segment using optical coherence tomography (OCT) imaging. The CD34+CD133+CD45low cells increased 68±59% 7days after bare metal stent (BMS), 10±53% after ZES (P<0.01 vs BMS), 3±49% after EES (P<0.001 vs BMS), compared with baseline. Percent change in CD34+CD133+CD45low cells was positively correlated with that in stromal cell-derived factor (SDF)-1α (R=0.29, P=0.034). Percentage of uncovered struts was higher in the EES group (14.4±17.3%), compared with the BMS (0.7±1.3, P<0.01) and ZES (0.4±0.5, P<0.01) groups. The change in CD34+CD133+CD45low cells showed positive correlation with OCT-quantified mean neointimal area (R=0.48, P<0.01). Finally, circulating mononuclear cells obtained from 5 healthy volunteers were isolated to determine the effect of sirolimus, zotarolimus and everolimus on vascular cell differentiation. The differentiation of mononuclear cells into endothelial-like cells was dose-dependently suppressed by sirolimus, zotarolimus, and everolimus. ConclusionsMobilization of progenitor cells was suppressed, and differentiation of mononuclear cells into endothelial-like cells was inhibited, in association with increased number of uncovered stent struts, even after second generation drug-eluting stenting. These data suggest that new approaches are necessary to enhance stent healing.

Correction: Covered vs. uncovered self-expandable metal stents for malignant distal biliary strictures: a systematic review and meta-analysis.

Background Self-expandable metal stents (SEMS) are used for palliation of distal malignant biliary strictures, but the role of covered SEMS is less clear. We performed an up-to-date meta-analysis to compare the performance of covered and uncovered SEMS in patients with unresectable distal malignant biliary strictures. Methods A computerized medical search was performed using MEDLINE, EMBASE, and the Cochrane Library between 2000 and December 2016 to identify all randomized trials that compared covered with uncovered SEMS in patients with distal malignant biliary strictures. Primary outcomes were stent failure and patient mortality; secondary outcomes were stent dysfunction and adverse events. Pooled estimates were computed using the random effects model. Results Overall, 11 RCTs involving 1272 patients were included. The primary outcomes of stent failure and patient mortality did not differ significantly between covered and uncovered SEMS (hazard ratio [HR] 0.68, 95 % confidence interval [CI] 0.40 – 1.17; HR 0.89, 95 %CI 0.76 – 1.05, respectively). However, stent migration and sludge formation were much more common with covered SEMS (odds ratio [OR] 5.11, 95 %CI 1.84 – 14.17; OR 2.46, 95 %CI 1.37 – 4.43). The use of covered SEMS was associated with a lower rate of tumor ingrowth (OR 0.21, 95 %CI 0.09 – 0.50) but a higher rate of tumor overgrowth (OR 2.00, 95 %CI 1.15 – 3.48) compared with uncovered stents. The rates of procedure-related adverse events were similar in both groups. Conclusion There was a risk reduction of about 32 % for both stent failure and patient mortality with covered SEMS but this difference was not significant. Migration and sludge rates were higher with covered SEMS, whereas tumor ingrowth was more likely with uncovered SEMS. The data show no added benefit of covered SEMS; further stent evolution is desirable.

In Vivo Evaluation of the Synergic Effect of Metformin and mTOR Inhibitors on the Endothelial Healing of Drug-eluting Stents in Diabetic Patients

Introduction and objectivesRecent animal studies have shown metformin (MF) to impair endothelialization of drug-eluting stents (DES). The aim of this study was to evaluate the effect of MF on the healing of DES in human coronary arteries of patients with diabetes mellitus by optical coherence tomography (OCT). MethodsThe RESERVOIR trial randomized 116 lesions in 112 patients with diabetes mellitus to amphilimus- or everolimus-eluting stents and included mandatory OCT at 9 months of follow-up. Patients were divided in 3 groups according to the glucose-lowering agents received: a) no MF; b) MF in noninsulin treated patients, and c) MF in insulin-treated patients. The primary safety endpoint was the rate of uncovered stents. ResultsSeventeen patients with 19 lesions did not receive MF, whereas MF was administered to 53 noninsulin treated patients (54 lesions) and 28 insulin-treated patients (28 lesions). Baseline characteristics were comparable, although noninsulin treated patients who received MF had better glycemic control (P < .01). By OCT, rates of uncovered struts were comparable between groups (3.07±4.80% vs 2.23±4.73% vs 3.43±6.69%, respectively; P = .48). Multivariate models confirmed that MF had no effect on the healing of DES (OR, 1.49, 95%CI, 0.71-3.08; P = .29). Similarly, quantitative angiography showed no effect of MF on late lumen loss, whereas patients treated with exogenous insulin had greater late lumen loss (P = .02). ConclusionsMetformin use does not impair endothelial healing of DES in patients with both insulin- and noninsulin-treated diabetes mellitus. According to these results, MF should not be discouraged in these patients.

New 14-mm diameter Niti-S biliary uncovered metal stent for unresectable distal biliary malignant obstruction.

AIMTo investigate whether an uncovered self-expandable metal stent (UCSEMS) with a large diameter could prevent recurrent biliary obstruction (RBO).METHODSThirty-eight patients with malignant biliary obstruction underwent treatment with an UCSEMS with a 14-mm diameter (Niti-S 14). Retrospectively, we evaluated technical and functional success rate, RBO rate, time to RBO, survival time, and adverse events in these patients.RESULTSStent placement success and functional success were achieved in all patients. Two patients (5.3%) had RBO due to tumor ingrowth or overgrowth. The median time to RBO was 190 (range, 164-215) d. The median survival time was 120 (range, 18-502) d. The 6-mo non-RBO rate was 91%. Other adverse events other than RBO occurred as follows: Acute cholecystitis, post-ERCP pancreatitis, hemobilia, and fever without exacerbation of liver injury, and liver abscess in 4 (10.3%), 3 (7.9%), 2 (5.3%), 1 (2.6%), and 1 (2.6%), respectively. Migration of the stents was not observed.CONCLUSIONNiti-S 14 is considered to be a preferable metal stent because of a low rate of RBO with no migration.

Irradiation stents vs. conventional metal stents for unresectable malignant biliary obstruction: A multicenter trial

Placement of an irradiation stent has been demonstrated to offer longer patency and survival than an uncovered self-expandable metallic stent (SEMS) in patients with unresectable malignant biliary obstruction (MBO). We aim to further assess the efficacy of an irradiation stent compared to an uncovered SEMS in those patients. We performed a randomized, open-label trial of participants with unresectable MBO at 20 centers in China. A total of 328 participants were allocated in parallel to the irradiation stent group (ISG) or the uncovered SEMS group (USG). Endpoints included stent patency (primary), technical success, relief of jaundice, overall survival, and complications. The first quartile stent patency time (when 25% of the patients experienced stent restenosis) was 212 days for the ISG and 104 days for the USG. Irradiation stents were significantly associated with a decrease in the rate of stent restenosis (9% vs. 15% at 90 days; 16% vs. 27% at 180 days; 21% vs. 33% at 360 days; p = 0.010). Patients in the ISG obtained longer survival time (median 202 days vs. 140 days; p = 0.020). No significant results were observed in technical success rate (93% vs. 95%; p = 0.499), relief of jaundice (85% vs. 80%; p = 0.308), and the incidence of grade 3 and 4 complications (8.5% vs. 7.9%; p = 0.841). Insertion of irradiation stents instead of uncovered SEMS could improve patency and overall survival in patients with unresectable MBO. For patients with unresectable malignant biliary obstruction (MBO), placement of a self-expandable metallic stent (SEMS) is a recommended palliative modality to relieve pruritus, cholangitis, pain, and jaundice. However, restenosis is a main pitfall after stent placement. Data from this first multicenter randomized controlled trial showed that insertion of an irradiation stent provided longer patency and better survival than a conventional metal stent. ClinicalTrials.gov ID: NCT02001779.