SciCombinator

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Concept: Restenosis

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BACKGROUND: The best way to manage restenosis in patients who have previously received a drug-eluting stent is unknown. We investigated the efficacy of paclitaxel-eluting balloons (PEB), paclitaxel-eluting stents (PES), and balloon angioplasty in these patients. METHODS: In this randomised, open-label trial, we enrolled patients older than 18 years with restenosis of at least 50% after implantation of any limus-eluting stent at three centres in Germany between Aug 3, 2009, and Oct 27, 2011. Patients were randomly assigned (1:1:1; stratified according to centre) to receive PEB, PES, or balloon angioplasty alone by means of sealed, opaque envelopes containing a computer-generated sequence. Patients and investigators were not masked to treatment allocation, but events and angiograms were assessed by individuals who were masked. The primary endpoint was diameter stenosis at follow-up angiography at 6-8 months. Primary analysis was done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00987324. FINDINGS: We enrolled 402 patients, of whom 137 (34%) were assigned to PEB, 131 (33%) to PES, and 134 (33%) to balloon angioplasty. Follow-up angiography at 6-8 months was available for 338 (84%) patients. PEB was non-inferior to PES in terms of diameter stenosis (38·0% [SD 21·5] vs 37·4% [21·8]; difference 0·6%, one-sided 95% CI 4·9%; p(non-inferiority)=0·007; non-inferiority margin of 7%). Findings were consistent in per-protocol analysis (p(non-inferiority)=0·011). PEB and PES were superior to balloon angioplasty alone (54·1% [25·0]; p(superiority)<0·0001 for both comparisons). Frequency of death, myocardial infarction, or target lesion thrombosis did not differ between groups. INTERPRETATION: By obviating the need for additional stent implantation, PEB could be a useful treatment for patients with restenosis after implantation of a drug-eluting stent. FUNDING: Deutsches Herzzentrum.

Concepts: Myocardial infarction, Atherosclerosis, Cardiology, Percutaneous coronary intervention, Stent, Radiology, Interventional cardiology, Restenosis

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Abstract Background: For the narrow ureter that will not accommodate a ureteroscope, it is common practice to place a ureteral stent, to allow subsequent ureteroscopy in the passively dilated ureter. Surprisingly, there are limited data on the effectiveness or safety of these maneuvers. Methods: We retrospectively analyzed patients managed with ureteral stent placement followed by another attempt at ureteroscopy after an initial attempt of flexible ureteroscopy failed because the ureteroscope would not pass up an otherwise normal ureter. Results: Of 41 patients with follow-up who underwent ureteral stenting for this reason, the ureteroscope passed with ease poststenting in 29 (71%) and there was continued resistance in 12. Of these 12 patients, the ureteroscopy was continued despite resistance in 9, while another stent was placed in the remaining 3. Of these three patients, the third attempt at ureteroscopy was successful in two, and further attempts at ureteroscopy were not made after the third attempt failed in one. With a mean overall follow-up of 32 months, two patients (5%) developed ureteral strictures. Both were among nine patients in whom repeat ureteroscopy was performed despite resistance, with a rate of obstruction of 22% in this subgroup. Overall, ureteral stenting allowed successful ureteroscopy in 98% of patients. Conclusions: Ureteral stenting with subsequent ureteroscopy is a successful and safe method of addressing a narrow ureter that initially does not allow passage of a flexible ureteroscope, as long as persistent subsequent attempts to insert the ureteroscope are made only if it passes easily.

Concepts: Stent, Restenosis, Renal pelvis, Coronary stent, Ureteric stent, PASS

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PURPOSE: The long-term success rate of dilation and/or internal urethrotomy is low in cases of recurrent urethral stricture disease. This study investigated the Memokath™044TW stent’s ability to maintain urethral patency after dilation or internal urethrotomy of recurrent urethral stricture. MATERIALS AND METHODS: Ninety-two patients with recurrent bulbar urethral strictures (mean length 2.7 cm) were treated with dilation or internal urethrotomy and randomized to short-term urethral catheter diversion (N=29) or insertion of a Memokath™044 stent (N=63). The primary endpoint was urethral patency as assessed by the passage of a calibrated endoscope. Secondary endpoints included urinary symptoms and uroflowmetry parameters. Stents were scheduled to remain in situ 12 months. RESULTS: The rate of successful stent insertion was 93.6% (59/63). The stented patients maintained patency significantly longer than controls (292 days vs. 84 days (median), p<0.001). The patency was reflected in significantly improved uroflowmetry and symptom scores. The stent was removed in 100% of patients. The most frequently noted side-effects in the stented patients were bacteriuria, hematuria, and penile pain - all usually mild and transient. There were no differences in sexual function between the Memokath and control patients. Stent dislocation and occlusion were observed in eight and three patients, respectively. CONCLUSIONS: Patients with recurrent bulbar urethral strictures treated with dilation or urethrotomy and a Memokath™044 stent maintained urethral patency significantly longer than those treated with dilation or urethrotomy alone. The stent's side-effect profile was favorable. The stent was straightforward to insert and was removed without difficulty - even after long-term placement.

Concepts: Time, Medical terms, Urethra, Stent, Restenosis, Urethral stricture, Urethrotomy, Insertion

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Current guidelines recommend combining clopidogrel with aspirin for up to 1 year after coronary stenting, but the value of clopidogrel beyond this time is uncertain.

Concepts: Cardiology, Percutaneous coronary intervention, Stent, Restenosis, Coronary stent, Bare-metal stent

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Objective: We compare clinical outcomes among unselected patients undergoing PCI with drug-eluting stents (DES) stratified in categories of treating hospital PCI volume. Background: Previous observational evidence suggests an inverse relation between hospital percutaneous coronary intervention (PCI) volume and patients' outcomes. However, there are no mid-term outcomes data with the use of drug-eluting stents (DES). Methods: We used data from DES.DE (German Drug-Eluting Stent) registry to compare in-hospital and 1-year outcomes among unselected patients. Primary endpoints at one year follow-up were the rate of major adverse cardiac and cerebrovascular events (MACCE) and target vessel revascularization (TVR). Results: Between 2005 and 2006, 2,075 patients were treated in group I hospitals (<1,000 PCIs/year), 1,624 in group II hospitals (1,000-1,500 PCIs/year) and 1,790 in group III hospitals (>1,500 PCIs/year). Compared with group II and group III, group I allocation was associated with higher rates of overall hospital mortality (1.1% versus 0.2% versus 0.2%; p<0.0001) and severe bleeding (1.0% versus 0.4% versus 0.5%; p<0.05); similarly, poorer outcomes with respect to MACCE (7.2% versus 6.5% versus 4.7%; p<0.01), stent thrombosis (5.2% versus 5.0% versus 3.0%; p<0.01) and non-fatal stroke (1.5% versus 0.9% versus 0.7%; p<0.05) were documented in group I. Conversely, TVR rates were highest in group II (10.2% versus 14.2% versus 11.7%; p<0.01); these differences persisted after risk adjustment for heterogeneous baseline characteristics. Conclusions: In the era of modern coronary intervention technological advances such as DES have not offset the inverse relation between procedural volume and both in-hospital and 1-year outcomes after PCI. © 2013 Wiley Periodicals, Inc.

Concepts: Hospital, Cardiology, Percutaneous coronary intervention, Stent, Restenosis, Drug-eluting stent, Coronary stent, Inverse relation

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OBJECTIVES: to assess the endothelial dysfunction (ED) after bare metal stents (BMS) and sirolimus eluting stents (SES) implantation in the same patient, overcoming the confounding role of individual variables. BACKGROUND: SES reduce restenosis rate compared to BMS but cause more ED. ED is a potentially unsafe phenomenon, since it is the first step in the cascade of atherosclerosis. Studies showing more pronounced ED with drug eluting stents than BMS involved different series of patients, making the comparison difficult because endothelial function (EF) is responsive to many risk factors. METHODS: we designed a prospective comparison of 6 months post-deployment EF of SES vs. BMS implanted in the same patient, but in different coronary segments. Forty-eight lesions were randomly assigned on a 1:1 allocation using block sizing of 4 according to a computer-generated sequence (SAS System, Version 9.1) basis to treatment with SES or BMS. The EF was evaluated by measuring vessel diameter variation in the stented segment, before and after selective intracoronary infusion of acetylcholine (iiAch). RESULTS: In eligible patients, the relative magnitudes of major vasoconstriction were 2.6, 2.9, 4.6, and 3.1 at 5 mm proximal and 5, 10 and 20 distal to the stent edge. Overall, a 3.5 fold major distal vasoconstriction after iiAch of SES vs. BMS was calculated. CONCLUSIONS: in the same patients, but treating different coronary segments, SES implantation induces a higher rate of vasoconstriction compared to BMS. The increased vasoconstriction after iiAch is an indicator of ED. © 2013 Wiley Periodicals, Inc.

Concepts: Atherosclerosis, Cardiology, Artery, Endothelium, Endothelial dysfunction, Restenosis, Drug-eluting stent, Bare-metal stent

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First-generation drug-eluting stents (DES) have been associated with impaired localized coronary vasomotion and delayed endothelialization. We aimed to compare coronary vasomotion after implantation of a newer-generation everolimus-eluting stent (EES), with a first-generation paclitaxel-eluting stent (PES). Coronary vasomotion was studied in 19 patients with EES and 13 with PES. Vasomotor response was measured proximally and distally to the stent and in a remote vessel (reference segment). Quantitative coronary angiography was performed offline. Endothelium independent vasomotion did not differ significantly between the two groups. EES showed significant vasodilatation while PES showed vasoconstriction at both proximal (+4.5 ± 3.6 vs -4.2 ± 6.9, p < 0.001) and distal (+4.6 ± 7.9 vs -4.8 ± 9.3, p = 0.003) segments. The reference segment did not show any significant difference in vasodilatation between the two groups (+9.8 ± 6.4 vs +7.2 ± 5.2, p = 0.17). Endothelium-dependent vasomotion at adjacent stent segments is relatively preserved after EES implantation while vasoconstriction was observed after PES implantation.

Concepts: Atherosclerosis, Cardiology, Atheroma, Stent, Radiology, Restenosis, Drug-eluting stent, Coronary stent

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Vertebral body stenting, or stentoplasty, is a novel percutaneous option in spinal cement augmentation. Conventional stentoplasty requires insertion of two paramedian stents per vertebral body through a bipedicular approach. We developed an unipedicular approach in which we implant a single stent into the midline of the vertebral body using cone-beam CT guidance and hereby describe the technical details and feasibility, in this technique that we termed “central stentoplasty.”

Concepts: Pregnancy, Percutaneous coronary intervention, Obstetrics, Vertebral column, Stent, Restenosis, Implantation

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Flow diverters (FDs) are increasingly used for complex intracranial aneurysms. As these self-expanding devices are deployed across an aneurysm neck, they can undergo deformations. The potential clinical consequences of FD deformations remain unclear. We describe an immediate thrombotic complication attributed to a stereotypical stenotic deformation of an FD extremity that can occur when landing zones are of insufficient length. This case is supplemented with in vitro studies showing the relationship between i) the length of the landing zones and ii) discrepancies between the diameter of the device and recipient vessel, and the severity of FD stenosis. In vitro, a shorter landing zone was associated with a progressive stenotic deformation of the terminal ends of all FDs studied. This deformation was more pronounced when the diameter of the device was oversized compared to the size of the recipient tube. In our clinical case, the presence of this deformation led to an immediate thrombotic complication, requiring deployment of a second stent to correct the observed stenosis. In addition, treatment failure ultimately led to a fatal rupture, a failure that can be explained by residual flows through a more porous transition zone, another characteristic FD deformation which occurs when they are oversized as compared to the parent vessel, but free to expand at the level of the aneurysm. Proper selection of device diameter and length of the landing zone is important, and may decrease the incidence of deformation-related complications.

Concepts: Atherosclerosis, Smoking, Stent, In vitro, Aneurysm, Restenosis, Diversion, Zone

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Progressive neointimal proliferation may lead to late restenosis and/or neoatherosclerosis after drug-eluting stent (DES) implantation. Late neointimal response may be different among different tissue characteristics. The aim of this study was to assess impact of in-stent neointimal characteristics on late neointimal response following DES implantation.

Concepts: Stent, Restenosis, Drug-eluting stent