Purpose of Review: Patients with stable coronary artery disease (CAD) and a high risk of bleeding are not ideal candidates for a polymer-based drug-eluting stent (DES) because it requires 6–12 months of dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI). The purpose of this review is to assess the angiographic and clinical outcomes of polymer-free drug-coated stents (PF-DCS) in stable CAD patients with a high bleeding risk. Recent Findings: Several randomized controlled trials (RCTs) have compared angiographic and clinical outcomes of PF-DCS with bare-metal stents (BMS), permanent polymer (PP)-DES, or biodegradable polymer (BP)-DES. However, none of these studies particularly recruited patients with stable CAD and a high risk of bleeding. Furthermore, there are limited data available on duration of DAPT following PF-DCS placement. Summary: PF-DCS has a better efficacy and similar safety as compared with BMS. PF-DCS with dual drug is noninferior to currently available PP-DES. Further RCTs are needed to assess the safety and efficacy of PF-DCS to BP-DES and PP-DES comparing shorter to standard durations of DAPT.

Background/Aims: Peripancreatic fluid collections (PFCs) result from acute or chronic pancreatic inflammation that suffers a rupture of its ducts. Currently, there exists three options for drainage or debridement of pancreatic pseudocysts and walled-off necrosis (WON). The traditional procedure is drainage by placing double pigtail plastic stents (DPPS); lumen-apposing metal stent (LAMS) has a biflanged design with a wide lumen that avoids occlusion with necrotic tissue, which is more common with DPPS and reduces the possibility of migration. We performed a systematic review and meta-analyses head-to-head, including only studies that compare the two main techniques to drainage of PFCs: LAMS vs DPPS. Methods: We conducted a systematic review in different databases, such as PubMed, OVID, Medline, and Cochrane Databases. This meta-analysis considers studies published from 2014 to 2020, including only studies that compare the two main techniques to drainage of PFCs: LAMS vs DPPS. Results: Thirteen studies were included in the meta-analyses. Only one of all studies was a randomized controlled trial. These studies comprise 1584 patients; 68.2% were male, and 31.8% were female. Six hundred sixty-three patients (41.9%) were treated with LAMS, and 921 (58.1%) were treated with DPPS. Six studies included only WON in their analysis, two included only pancreatic pseudocysts, and five studies included both pancreatic pseudocysts and WON. The technical success was similar in patients treated with LAMS and DPPS (97.6% vs 97.5%, respectively, P =.986, RR = 1.00 [95% CI 0.93-1.08]). The clinical success was similar in both groups (LAMS: 90.1% vs DPPS: 84.2%, P =.139, RR = 1.063 [95% CI 0.98-1.15]). Patients treated with LAMS had a lower complication rate than the DPPS groups, with a significant statistical difference (LAMS: 16.0% vs DPPS: 20.2%, P =.009, RR = 0.746 [95% CI 0.60-0.93]). Bleeding was the most common complication in the LAMS group (33 patients, [5.0%]), whereas infection was the most common complication in the DPPS group (56 patients, [6.1%]). The LAMS migration rate was lower than in the DPPS (0.9% vs 2.2%, respectively, P =.05). The mortality rate was similar in both groups, 0.6% in the LAMS group (four patients) and 0.4% in the DPPS group (four patients; P =.640). Conclusion: The PFCs drainage is an indication when persistent symptoms or PFCs-related complications exist. EUS guided drainage with LAMS has similar technical and clinical success to DPPS drainage for the management of PFCs. The technical and clinical success rates are high in both groups. However, LAMS drainage has a lower adverse events rate than DPPS drainage. More randomized controlled trials are needed to confirm the real advantage of LAMS drainage over DPPS drainage. / Revisión por pares

El documento digital no refiere asesor / Establece el efecto de la bivalirudina como anticoagulante en la implantación de stents coronarios por insuficiencia coronaria aguda o crónica en comparación a la heparina no fraccionada. Realiza un estudio de cohorte de diseño observacional, descriptivo, longitudinal y retrospectivo realizado en pacientes sometidos a ACTP en el Centro Médico Naval CEMENA de julio 2006 a junio 2007. Se determinaron las características clínicas, electrocardiográficas, angiográficas, resultados de la angioplastía y las complicaciones cardiovasculares mayores a los 7 días, 30 días y 6 meses. Se realizaron angioplastias coronarias con implantación de stent a 79 pacientes, de los cuales 42 cumplieron los criterios de inclusión y ninguno de exclusión, predominó el sexo masculino (86%) y el grupo de más de 64 años (64%). La edad media fue 67.1 ±15 años.Los factores de riesgo más frecuentes son tabaquismo (23%), diabetes (40%), dislipidemia (82%) e 6 hipertensión arterial (85.5%). Se encontró la presencia de muerte cardiaca, reinfarto y necesidad de revascularización en 2 casos en el grupo de bivalirudina (8%) y 4 casos en el grupo de heparina (22%) con diferencia estadísticamente significativa. No se presentaron casos de oclusión aguda o complicaciones postangioplastía (hematoma en zona de punción o sangrado) en ninguno de los dos grupos. Concluye que en ambos grupos (bivalirudina vs heparina no fraccionada) no se observó casos de oclusión aguda del stent implantado ni complicaciones post-angioplastía. La presencia de muerte cardiaca, re-infarto y/o necesidad de revascularización fue mayor para el grupo de heparina. / Trabajo académico

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Esophageal and biliary stents are indwelling devices used in the treatment of selected gastrointestinal and biliary disorders. Stenting is accepted as a standard procedure for palliation of malignant obstruction of the esophagus and biliary system. Review of the early and late complications associated with these devices is made with emphasis on the clinical and radiographic features. A suggested approach to diagnosis and treatment recommendations are made for each complication that the emergency department physician may encounter.

No description available.

No description available.

Coronary stents have become a very popular treatment for cardiovascular disease, historically the leading cause of death in the United States. Stents, while successful in the short term, are subject to high failure rates (up to 24% in the first six months) due to wall regrowth and clotting, probably due to a combination of abnormal mechanical stresses and disruption of the arterial blood flow. The goal of this research was to develop recommendations concerning ways in which stent design might be improved, focusing on the problem of pressure wave reflections. A one-dimensional finite-difference model was developed to predict these reflections, and effects of variations in stent and vessel properties were examined, including stent stiffness, length, and compliance transition region, as well as vessel radius and wall thickness. The model was solved using a combination of Weighted Essentially Non-Oscillatory (WENO) and Runge-Kutta methods. Over 100 cases were tested. Results showed that reasonable variations in these parameters could induce changes in reflection magnitude of up to ±50%. It was also discovered that the relationship between each of these properties and the resulting wave reflection could be described simply, and the effect of all of them together could in fact be encompassed by a single non-dimensional parameter. This parameter was titled"Stent Authority," and several variations were proposed. It is believed this parameter is a novel way of relating the energy imposed upon the arterial wall by the stent, to the fraction of the incident pressure energy which is reflected from the stented region. / Master of Science

Fundamentos: A caracterização precisa da interação da placa aterosclerótica no momento do implante do stent é crucial para o entendimento da complacência e da cicatrização vasculares. Objetivamos investigar se a composição da placa avaliada pela tomografia de coerência óptica (OCT), influencia as alterações agudas no procedimento índice do implante do stent e na cicatrização vascular no seguimento tardio. Métodos: Os pacientes tratados com um único tipo de stent eluidor de fármaco (cromo cobalto, eluidor de sirolimus e polímero bioabsorvível) foram incluídos prospectivamente, seguindo um protocolo com etapas de dilatações progressivas do vaso. As imagens de OCT sequenciais foram realizadas no procedimento índice (basal e a cada etapa do protocolo) e no seguimento tardio, co-registradas e analisadas a cada 0,6mm. A avaliação semiquantitativa da placa foi realizada dividindo-se secções transversas em 4 quadrantes, com cada quadrante rotulado de acordo com o seu componente mais prevalente (fibrótico, calcificado, lipídico, normal). A interação stent-vaso avaliada pela OCT foi utilizada como indicador substituto para lesão e cicatrização vasculares após o implante do stent. Resultados: Um total de 22 lesões (1stent/lesão) de 20 pacientes e 2298 seções transversas de OCT foram analisadas no procedimento índice. O reestudo com OCT foi realizado em 17 pacientes e 19 lesões (86%). O componente de placa predominante foi fibrótico (fibrótico = 46.84 ± 16%; lipídico = 17.63 ± 10.72%; calcificado = 4.63 ± 5.9%; normal = 29.16 ± 12.24; não analizável=1.74 ± 5.35%). Houve um aumento nas áreas da luz (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) e do stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001), com um aumento na área do prolapso tecidual (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segmentos com muito tecido fibrocalcificado tiveram áreas luminais menores ao longo das etapas da intervenção. Por outro lado, placas com muito conteúdo lipídico ou vaso normal tiveram maiores ganhos nas medidas das áreas luminais mínimas ao longo das dilatações sequenciais. Além disso, placas com muito tecido fibrocalcificado no momento basal apresentaram menor crescimento neointimal no seguimento tardio, enquanto que o grau de conteúdo lipídico e de vaso normal não tiveram impacto sobre a formação do tecido neointimal. Os indicadores substitutos de lesão vascular após o implante do stent correlacionaram-se significativamente com o crescimento neointimal no seguimento tardio. Conclusões: A composição tecidual das placas subjacentes influencia significativamente o comportamento mecânico agudo e a longo prazo dos vasos coronarianos submetidos ao implante de stent. Além disso, a lesão vascular após o implante do stent está potencialmente ligada ao futuro crescimento neointimal no seguimento tardio / Background Accurate characterization of atherosclerotic plaque interaction during stent deployment is crucial to understand vascular compliance and healing. We sought to determine whether plaque composition assessed by optical coherence tomography (OCT), influences acute changes at index procedure and vascular healing at follow up. Methods Patients treated with a single drug-eluting stent type (cobalt chromium with bioabsorbable polymer eluting sirolimus stent) were prospectively included, following a pre-defined step-by-step progressive vessel dilatation. Sequential OCT imaging were performed at the index procedure (baseline and at each time point of the protocol) and at follow up, co-registered and analyzed every 0.6mm for quantitative measurements. Semi-quantitative plaque assessment was performed at baseline by dividing cross-sections into 4 quadrants, with each quadrant labeled according to its most prevalent component (fibrotic, calcific, lipid). OCT assessments of stent-vessel interactions were used as a surrogate for vessel injury and healing after stent implantation. Results A total of 22 lesions (1stent/lesion) of 20 patients and 2298 OCT crosssections were analyzed at the index procedure. For an average of 19.7 months (591.88 ± 60.52 days), 17 of the patients and 19 lesions (86%) underwent OCT imaging at follow up. The predominant percentage plaque component was fibrotic (fibrotic = 46.84 ± 16%; lipid = 17.63 ± 10.72%; calcific = 4.63 ± 5.9%; normal = 29.16 ± 12.24; non-analyzable = 1.74 ± 5.35%). There was an increase in lumen (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) and stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001) areas, with an increase in tissue prolapse area (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segments with high fibrocalcific content tended to have decreased minimal luminal areas along the intervention time-points. Conversely, plaques with high lipid content had increased minimal luminal areas during sequential dilatations. Moreover, plaques with high fibrocalcific tissue at baseline had significantly smaller neointimal growth at follow-up, whereas the degree of lipid content or normal tri-layered vessel had no impact on neointimal formation. OCT surrogates of vessel injury after coronary stenting significantly correlated with neointimal growth at follow-up. Conclusions: Tissue composition of underlying plaques significantly influences the acute mechanical and the long-term behavior of coronary vessels undergoing stent implantation. In addition, vessel injury after coronary stenting is potentially linked to future neointimal growth at follow-up