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1.
JAMA Netw Open ; 5(1): e2142210, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34994793

RESUMO

Importance: A surge of COVID-19 occurred from March to June 2021, in New Delhi, India, linked to the B.1.617.2 (Delta) variant of SARS-CoV-2. COVID-19 vaccines were rolled out for health care workers (HCWs) starting in January 2021. Objective: To assess the incidence density of reinfection among a cohort of HCWs and estimate the effectiveness of the inactivated whole virion vaccine BBV152 against reinfection. Design, Setting, and Participants: This was a retrospective cohort study among HCWs working at a tertiary care center in New Delhi, India. Exposures: Vaccination with 0, 1, or 2 doses of BBV152. Main Outcomes and Measures: The HCWs were categorized as fully vaccinated (with 2 doses and ≥15 days after the second dose), partially vaccinated (with 1 dose or 2 doses with <15 days after the second dose), or unvaccinated. The incidence density of COVID-19 reinfection per 100 person-years was computed, and events from March 3, 2020, to June 18, 2021, were included for analysis. Unadjusted and adjusted hazard ratios (HRs) were estimated using a Cox proportional hazards model. Estimated vaccine effectiveness (1 - adjusted HR) was reported. Results: Among 15 244 HCWs who participated in the study, 4978 (32.7%) were diagnosed with COVID-19. The mean (SD) age was 36.6 (10.3) years, and 55.0% were male. The reinfection incidence density was 7.26 (95% CI: 6.09-8.66) per 100 person-years (124 HCWs [2.5%], total person follow-up period of 1696 person-years as time at risk). Fully vaccinated HCWs had lower risk of reinfection (HR, 0.14 [95% CI, 0.08-0.23]), symptomatic reinfection (HR, 0.13 [95% CI, 0.07-0.24]), and asymptomatic reinfection (HR, 0.16 [95% CI, 0.05-0.53]) compared with unvaccinated HCWs. Accordingly, among the 3 vaccine categories, reinfection was observed in 60 of 472 (12.7%) of unvaccinated (incidence density, 18.05 per 100 person-years; 95% CI, 14.02-23.25), 39 of 356 (11.0%) of partially vaccinated (incidence density 15.62 per 100 person-years; 95% CI, 11.42-21.38), and 17 of 1089 (1.6%) fully vaccinated (incidence density 2.18 per 100 person-years; 95% CI, 1.35-3.51) HCWs. The estimated effectiveness of BBV152 against reinfection was 86% (95% CI, 77%-92%); symptomatic reinfection, 87% (95% CI, 76%-93%); and asymptomatic reinfection, 84% (95% CI, 47%-95%) among fully vaccinated HCWs. Partial vaccination was not associated with reduced risk of reinfection. Conclusions and Relevance: These findings suggest that BBV152 was associated with protection against both symptomatic and asymptomatic reinfection in HCWs after a complete vaccination schedule, when the predominant circulating variant was B.1.617.2.


Assuntos
COVID-19/epidemiologia , Pessoal de Saúde , Reinfecção , SARS-CoV-2 , Adulto , COVID-19/etiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Estudos de Coortes , Feminino , Humanos , Imunogenicidade da Vacina , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Centros de Atenção Terciária , Vacinas de Produtos Inativados/administração & dosagem , Vírion/imunologia , Adulto Jovem
2.
Mol Pharm ; 18(11): 3999-4014, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570503

RESUMO

Amorphous solid dispersions (ASDs) are commonly used to orally deliver small-molecule drugs that are poorly water-soluble. ASDs consist of drug molecules in the amorphous form which are dispersed in a hydrophilic polymer matrix. Producing a high-performance ASD is critical for effective drug delivery and depends on many factors such as solubility of the drug in the matrix and the rate of drug release in aqueous medium (dissolution), which is linked to bioperformance. Often, researchers perform a large number of design iterations to achieve this objective. A detailed molecular-level understanding of the mechanisms behind ASD dissolution behavior would aid in the screening, designing, and optimization of ASD formulations and would minimize the need for testing a wide variety of prototype formulations. Molecular dynamics and related types of simulations, which model the collective behavior of molecules in condensed phase systems, can provide unique insights into these mechanisms. To study the effectiveness of these simulation techniques in ASD formulation dissolution, we carried out dissipative particle dynamics simulations, which are particularly an efficient form of molecular dynamics calculations. We studied two stages of the dissolution process: the early-stage of the dissolution process, which focuses on the dissolution at the ASD/water interface, and the late-stage of the dissolution process, where significant drug release would have occurred and there would be a mixture of drug and polymer molecules in a predominantly aqueous environment. Experimentally, we used Fourier transform infrared spectroscopy to study the interactions between drugs, polymers, and water in the dry and wet states and the chromatographic technique to study the rate of drug and polymer release. Both experiments and simulations provided evidence of polymer microstructures and drug-polymer interactions as important factors for the dissolution behavior of the investigated ASDs, consistent with previous work by Pudlas et al. (Eur. J. Pharm. Sci. 2015, 67, 21-31). As experimental and simulation results are consistent and complementary, it is clear that there is significant potential for combined experimental and computational research for a detailed understanding of ASD formulations and, hence, formulation optimization.


Assuntos
Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Excipientes/química , Polímeros/química , Disponibilidade Biológica , Química Farmacêutica , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
3.
ISA Trans ; 114: 331-346, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33408036

RESUMO

This article presents a unified approach of controller design in cascade control structure (CCS) for unstable, integrating and stable processes with dead-time to achieve enhanced load disturbance rejection. The design of inner and outer loop controllers in CCS is based, partially on the direct synthesis approach and partially on the pole placement method. First, the parameters of the inner loop controller are obtained and then the outer loop controller is designed by considering the inner loop as a part of the primary plant. The proposed design approach deals with a wide range of processes having unstable, integrating and stable dynamics in a unified way. It is applied directly on the higher and lower order processes, as the proposed strategy is acquitted from the approximation of the dead-time and model order reduction of the plant. Simulations have been conducted to show the efficacy of the present approach. The results shows that the present approach provides enhanced regulatory performance as compared to the recently reported approaches from the literature.

4.
Chem Sci ; 10(36): 8374-8383, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31762970

RESUMO

The process of developing new compounds and materials is increasingly driven by computational modeling and simulation, which allow us to characterize candidates before pursuing them in the laboratory. One of the non-trivial properties of interest for organic materials is their packing in the bulk, which is highly dependent on their molecular structure. By controlling the latter, we can realize materials with a desired density (as well as other target properties). Molecular dynamics simulations are a popular and reasonably accurate way to compute the bulk density of molecules, however, since these calculations are computationally intensive, they are not a practically viable option for high-throughput screening studies that assess material candidates on a massive scale. In this work, we employ machine learning to develop a data-derived prediction model that is an alternative to physics-based simulations, and we utilize it for the hyperscreening of 1.5 million small organic molecules as well as to gain insights into the relationship between structural makeup and packing density. We also use this study to analyze the learning curve of the employed neural network approach and gain empirical data on the dependence of model performance and training data size, which will inform future investigations.

5.
Phys Chem Chem Phys ; 21(8): 4452-4460, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30734777

RESUMO

In a previous study, we introduced a new computational protocol to accurately predict the index of refraction (RI) of organic polymers using a combination of first-principles and data modeling. This protocol is based on the Lorentz-Lorenz equation and involves the calculation of static polarizabilities and number densities of oligomer sequences, which are extrapolated to the polymer limit. We chose to compute the polarizabilities within the density functional theory (DFT) framework using the PBE0/def2-TZVP-D3 model chemistry. While this ad hoc choice proved remarkably successful, it is also relatively expensive from a computational perspective. It represents the bottleneck step in the overall RI modeling protocol, thus limiting its utility for virtual high-throughput screening studies, in which efficiency is essential. For polymers that exhibit late-onset extensivity, the employed linear extrapolation scheme can require demanding calculations on long-oligomer sequences, thus becoming another bottleneck. In the work presented here, we benchmark DFT model chemistries to identify approaches that optimize the balance between accuracy and efficiency for this application domain. We compare results for conjugated and non-conjugated polymers, augment our original extrapolation approach with a non-linear option, analyze how the polarizability errors propagate into the RI predictions, and offer guidance for method selection.

6.
J Chem Phys ; 148(24): 241712, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29960320

RESUMO

Organic materials with a high index of refraction (RI) are attracting considerable interest due to their potential application in optic and optoelectronic devices. However, most of these applications require an RI value of 1.7 or larger, while typical carbon-based polymers only exhibit values in the range of 1.3-1.5. This paper introduces an efficient computational protocol for the accurate prediction of RI values in polymers to facilitate in silico studies that can guide the discovery and design of next-generation high-RI materials. Our protocol is based on the Lorentz-Lorenz equation and is parametrized by the polarizability and number density values of a given candidate compound. In the proposed scheme, we compute the former using first-principles electronic structure theory and the latter using an approximation based on van der Waals volumes. The critical parameter in the number density approximation is the packing fraction of the bulk polymer, for which we have devised a machine learning model. We demonstrate the performance of the proposed RI protocol by testing its predictions against the experimentally known RI values of 112 optical polymers. Our approach to combine first-principles and data modeling emerges as both a successful and a highly economical path to determining the RI values for a wide range of organic polymers.

7.
Circulation ; 136(6): 566-582, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28487392

RESUMO

BACKGROUND: Atherosclerotic plaque formation results from chronic inflammation and fibroproliferative remodeling in the vascular wall. We previously demonstrated that both human and mouse atherosclerotic plaques show elevated expression of EphA2, a guidance molecule involved in cell-cell interactions and tumorigenesis. METHODS: Here, we assessed the role of EphA2 in atherosclerosis by deleting EphA2 in a mouse model of atherosclerosis (Apoe-/-) and by assessing EphA2 function in multiple vascular cell culture models. After 8 to 16 weeks on a Western diet, male and female mice were assessed for atherosclerotic burden in the large vessels, and plasma lipid levels were analyzed. RESULTS: Despite enhanced weight gain and plasma lipid levels compared with Apoe-/- controls, EphA2-/-Apoe-/- knockout mice show diminished atherosclerotic plaque formation, characterized by reduced proinflammatory gene expression and plaque macrophage content. Although plaque macrophages express EphA2, EphA2 deletion does not affect macrophage phenotype, inflammatory responses, and lipid uptake, and bone marrow chimeras suggest that hematopoietic EphA2 deletion does not affect plaque formation. In contrast, endothelial EphA2 knockdown significantly reduces monocyte firm adhesion under flow. In addition, EphA2-/-Apoe-/- mice show reduced progression to advanced atherosclerotic plaques with diminished smooth muscle and collagen content. Consistent with this phenotype, EphA2 shows enhanced expression after smooth muscle transition to a synthetic phenotype, and EphA2 depletion reduces smooth muscle proliferation, mitogenic signaling, and extracellular matrix deposition both in atherosclerotic plaques and in vascular smooth muscle cells in culture. CONCLUSIONS: Together, these data identify a novel role for EphA2 in atherosclerosis, regulating both plaque inflammation and progression to advanced atherosclerotic lesions. Cell culture studies suggest that endothelial EphA2 contributes to atherosclerotic inflammation by promoting monocyte firm adhesion, whereas smooth muscle EphA2 expression may regulate the progression to advanced atherosclerosis by regulating smooth muscle proliferation and extracellular matrix deposition.


Assuntos
Aterosclerose/patologia , Receptor EphA2/genética , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Feminino , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Inflamação , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Fenótipo , Placa Aterosclerótica/patologia , Receptor EphA2/deficiência , Receptor EphA2/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
8.
Cardiovasc Eng Technol ; 8(1): 81-90, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28160266

RESUMO

Stent implants are essential in restoring normal blood flow in atherosclerotic arteries. Recent studies have shown high failure rates of stent implants in superficial femoral artery (SFA) as a result of dynamic loading environment imposed on the stent implants by the diseased arterial wall and turbulent blood flow. There are variety of stent designs and materials currently on the market however, there is no clear understanding if specific stent design is suitable with the material that is manufactured from and if this combination can sustain the life-cycle that the stent implants need to undergo once inside the artery. Lack of studies have been presented that relate stent mechanical properties with stent geometry and material used. This study presents linear theoretical and computational modeling approach that determines stent mechanical properties with effective stiffness of the deployed stent. Effective stiffness of the stent has been accurately derived based on stent structure design and loading in axial and radial directions. A rhombus stent structure was selected for this study due to its more common use and produced by main stream manufacturers. The derived theoretical model was validated using numerical finite element modeling approach. Results from this study can lead to preliminary insight towards understanding of stent deformation based on stent geometry, material properties and artery wall pressure; and how to carefully match stent's geometry with suitable material for long life cycle, increased strength, and reliable performance of stent implants.


Assuntos
Fenômenos Biomecânicos , Modelos Cardiovasculares , Stents , Artérias/cirurgia , Prótese Vascular , Simulação por Computador , Análise de Elementos Finitos , Humanos , Desenho de Prótese
9.
Cardiovasc Eng Technol ; 7(4): 448-454, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27848221

RESUMO

High entropy alloys (HEAs) are new class of metallic materials with five or more principal alloying elements. Due to this distinct concept of alloying, the HEAs exhibit unique properties compared to conventional alloys. The outstanding properties of HEAs include increased strength, superior wear resistance, high temperature stability, increased fatigue properties, good corrosion, and oxidation resistance. Such characteristics of HEAs have generated significant interest among the scientific community. However, their applications are yet to be explored. This paper discusses the mechanical behavior and microstructure of Al0.1CoCrFeNi HEA subjected to thermo-mechanical processing, and its potential application in peripheral vascular stent implants that are prone to high failure rates. Results show that Al0.1CoCrFeNi alloy possesses characteristics that compare well against currently used stent materials and it can potentially find use in peripheral vascular stent implants and extend their life-cycle.


Assuntos
Ligas/química , Metais Pesados/química , Stents , Entropia , Análise de Elementos Finitos , Teste de Materiais , Análise Espectral
10.
JACC Cardiovasc Interv ; 9(21): 2243-2252, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27832850

RESUMO

OBJECTIVES: The aim of this study was to assess actual procedural costs and outcomes comparing wire-catheter and dedicated chronic total occlusion (CTO) device strategies to cross peripheral artery CTOs. BACKGROUND: Peripheral artery CTO interventions are frequently performed, but there are limited data on actual procedural costs and outcomes comparing wire-catheter and dedicated CTO devices. METHODS: The XLPAD (Excellence in Peripheral Artery Disease Intervention) registry (NCT01904851) was accessed to retrospectively compare cost and 30-day and 12-month outcomes of wire-catheter and crossing device strategies for treatment of infrainguinal peripheral artery CTO. RESULTS: Of all 3,234 treated lesions, 42% (n = 1,362) were CTOs in 1,006 unique patients. Wire-catheter approaches were used in 82% of CTOs, whereas dedicated CTO devices were used in 18% (p < 0.0001). CTO crossing device use was associated with significantly higher technical success (74% vs. 65%; p < 0.0001) and mean procedure cost ($7,800.09 vs. $4,973.24; p < 0.0001). Because 12-month repeat revascularization (11.3% vs. 17.2%; p = 0.02) and amputation rates (2.8% vs. 8.5%; p = 0.002) in the CTO crossing device arm were lower compared with the wire-catheter group, the net cost for an initial CTO crossing device strategy was $423.80 per procedure. CONCLUSIONS: An initial wire-catheter approach to cross a peripheral artery CTO is most frequently adopted. The use of dedicated CTO crossing devices provides significantly higher technical success and lower reintervention and amputation rates, at a net cost of $423.80 per procedure at 12 months.


Assuntos
Procedimentos Endovasculares/economia , Procedimentos Endovasculares/instrumentação , Custos de Cuidados de Saúde , Doença Arterial Periférica/economia , Doença Arterial Periférica/terapia , Avaliação de Processos em Cuidados de Saúde/economia , Dispositivos de Acesso Vascular/economia , Idoso , Amputação/economia , Doença Crônica , Procedimentos Endovasculares/efeitos adversos , Desenho de Equipamento , Feminino , Humanos , Salvamento de Membro/economia , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Doença Arterial Periférica/diagnóstico , Sistema de Registros , Retratamento/economia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
11.
J Invasive Cardiol ; 28(8): 330-3, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27187983

RESUMO

BACKGROUND: The risk of distal embolization (DE) during infrainguinal peripheral artery interventions (PAI) is often mitigated by the use of embolic protection devices. There are limited data on the use of filters with the Jetstream (JS) atherectomy device, a rotational cutter with aspiration capacity. The Nav-6 filter is uniquely suited for use with the JS due to its wire compatibility and detachment from the filter; however, data on the off-label use of this combination have not been reported. METHODS: Consecutive patients between October 2008 and April 2015 undergoing endovascular infrainguinal PAI with JS were analyzed as part of the Excellence in Peripheral Artery Disease (XL-PAD) registry (NCT01904851). Patients were divided into two subgroups with Nav-6 filter use vs no filter use. Descriptive and univariate analyses were performed. RESULTS: Among 141 patients (mean age, 67.8 ± 10.8 years; 169 lesions) included in this study, the Nav-6 filter was used in 82 (59%). Use of a filter was more frequent in longer lesions (146 ± 106 mm vs 91 ± 72 mm; P=.01), in more severe stenoses (95% vs 87%; P=.04), and in chronic total occlusions (33% vs 8.3%; P=.01). Patients receiving filters had longer procedure duration (102 ± 51 min vs 66 ± 41 min; P=.01) and longer fluoroscopy times (31 ± 16 min vs 21 ± 10 min; P<.001). Use of the Nav-6 filter with the JS during PAI was associated with numerically lower rates of DE (1.8% vs 8%; P=.10) and similar rates of death and amputation. At 12 months, the target-lesion revascularization rate was higher in the filter group (22% vs 2.7%; P=.02), likely secondary to use of the filter in more complex lesions. CONCLUSION: Nav-6 filter during JS atherectomy was predominantly used during complex infrainguinal PAI and was associated with less occurrence of DE.


Assuntos
Angioplastia com Balão , Aterectomia , Dispositivos de Proteção Embólica , Embolia/prevenção & controle , Doença Arterial Periférica , Idoso , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Angioplastia com Balão/métodos , Aterectomia/efeitos adversos , Aterectomia/instrumentação , Aterectomia/métodos , Dispositivos de Proteção Embólica/efeitos adversos , Dispositivos de Proteção Embólica/estatística & dados numéricos , Embolia/epidemiologia , Embolia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/cirurgia , Sistema de Registros , Estados Unidos/epidemiologia , Grau de Desobstrução Vascular
12.
J Endovasc Ther ; 23(2): 339-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26921281

RESUMO

PURPOSE: To evaluate the outcomes and stent-device interaction of the JetStream atherectomy device in the treatment of in-stent restenosis (ISR) of the femoropopliteal segment. METHODS: The JetStream XC atherectomy device, a rotational cutter with aspiration capacity, was evaluated in a prospective cohort of 29 patients (mean age 69.9 ± 11.7 years; 11 men) with femoropopliteal ISR in 32 limbs (ClinicalTrials.gov identifier NCT01722877). Lesion length was 17.4 ± 13.1 cm. The primary effectiveness outcome was acute success (≤ 30% residual narrowing with no serious adverse events). The primary safety endpoint was major adverse events. Secondary endpoints included clinically driven target lesion revascularization (TLR) at 6 months and 1 year and loss of stent integrity as assessed by an angiographic core laboratory. RESULTS: Treated length was 19.5 ± 12.9 cm. Acute success was obtained in 29/32 (91%) limbs. Acute device success (<50% residual narrowing after atherectomy alone) was 76% (22/29). Adjunctive balloon angioplasty was performed in all cases at a mean pressure of 11.6 ± 3.3 atm. Embolic filter protection was used in 16 (50%) of 32 limbs. Macrodebris was noted in 2 (12%) of 16 filters. Distal embolization requiring treatment occurred in 3/32 (9.4%) limbs (2 with no filter). Other non-procedure-related adverse events were 1 (3%) death (nonvascular) and 1 (3%) case of major bleeding. There were no new stent fractures or deformities (n=24) postatherectomy. Follow-up was completed on 27 patients (29 limbs) at 6 and 12 months. TLR at these time points occurred in 4/29 (14%) and 12/29 (41%) patients. Patency (duplex-derived peak systolic velocity ratio <2.4) was 72% at 6 months. CONCLUSION: JetStream atherectomy using the XC device has favorable acute results in treating femoropopliteal ISR with high procedure success, no device-stent interaction, and favorably low TLR rates. A multicenter trial is needed to confirm these results.


Assuntos
Aterectomia/métodos , Procedimentos Endovasculares/instrumentação , Artéria Femoral , Doença Arterial Periférica/terapia , Artéria Poplítea , Stents , Idoso , Idoso de 80 Anos ou mais , Aterectomia/efeitos adversos , Constrição Patológica , Procedimentos Endovasculares/efeitos adversos , Estudos de Viabilidade , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/fisiopatologia , Estudos Prospectivos , Recidiva , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Estados Unidos , Grau de Desobstrução Vascular
13.
Circ Cardiovasc Interv ; 9(2): e002730, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26839391

RESUMO

BACKGROUND: There are limited data on femoropopliteal artery stent thrombosis (ST), which is a serious adverse outcome of peripheral artery interventions. METHODS AND RESULTS: Index procedures resulting in femoropopliteal ST were compared with stent procedures without subsequent ST in the Excellence in Peripheral Artery Disease registry. The study data had a total of 724 cases of stent procedures and 604 unique patients. Femoropopliteal ST occurred in 26 of 604 patients (4.3%) over a median follow-up of 6 months post procedure. ST was more likely to occur in men (96.3% versus 82.2%; P=0.026) and to have an initial intervention for chronic total occlusions (88.5% versus 64.0%; P=0.01). There was no significant difference in ST between drug-coated and bare-metal stents (4.4% versus 3.4%; P=0.55), but the rate of ST was significantly higher with self-expanding covered stent grafts compared with bare-metal stents (10.6% versus 3.4%; P=0.02). ST was significantly associated with an increased risk of 12-month major adverse limb events (hazard ratio, 4.99; 95% confidence interval, 2.31-10.77; P<0.001) compared with no ST. On multivariate analysis, treatment of chronic total occlusion lesions (odds ratio, 3.46; 95% confidence interval, 0.98-12.20; P=0.05) and in-stent restenosis lesions (odds ratio, 5.30; 95% confidence interval, 1.83-15.32; P=0.002) were independently associated with an increased risk of ST. CONCLUSIONS: In a multicenter peripheral interventional registry, femoropopliteal ST occurred in 4.3% of patients who underwent stent procedures, and it was associated with treatment of chronic total occlusions and in-stent restenosis lesions, and had higher 12-month major adverse limb events. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01904851.


Assuntos
Oclusão de Enxerto Vascular/epidemiologia , Perna (Membro)/irrigação sanguínea , Sistema de Registros , Humanos , Estados Unidos/epidemiologia
14.
Catheter Cardiovasc Interv ; 88(7): 1046-1055, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26707858

RESUMO

BACKGROUND: In the RadiCure study 505 catheterization procedures were 1:1 randomized to use or no use of real-time radiation monitoring. Use of the Bleeper Sv monitor resulted in a significant reduction in operator radiation exposure. METHODS: We examined the association between several baseline and procedural parameters with operator and patient radiation exposure using univariable and multivariable analysis in the 505 patients that were enrolled in RadiCure. All baseline demographic and procedure characteristics recorded were included in the univariable analysis. RESULTS: Median fluoroscopy time was 6.2 (2.5-12.5) minutes, median patient air kerma dose was 0.908 (0.602-1.636) Gray and median first operator exposure was 10 (5-22) µSv. For analysis purposes, the 505 procedures were dichotomized based on the median operator exposure (10 µSv) and median patient radiation dose (0.908 Gray). On multivariable analysis, factors associated with high (above median or >10 µSv) first operator radiation exposure included radial access (odds ratio [OR] 5.44, 95% Confidence Interval [CI] 2.88-10.76), chronic total occlusion (CTO) intervention (OR 12.78, 95% CI 4.42-43.60), real-time radiation monitoring (OR 0.42, 95% CI 0.26-0.66), and use of a radioabsorbent drape (OR 0.53, 95% CI 0.28-0.96). High patient radiation dose (above median or >0.908 Gray) was associated with body mass index>30 kg/m2 (OR 3.22, 95% CI 1.99-5.29), prior MI (OR 2.26, 95% CI 1.29-4.04), prior cerebrovascular disease (OR 0.34, 95% CI 0.15-0.75), hypertension (OR 2.40, 95% CI 1.05-5.82), prior coronary artery bypass graft surgery (OR 2.46, 95% CI 1.40-4.39) and CTO intervention (OR 12.93, 95% CI 3.28-87.31), but was not associated with real-time radiation monitoring and use of a radioabsorbent drape. CONCLUSIONS: Several clinical and procedural factors are associated with higher patient and operator radiation exposure. Real-time radiation monitoring and use of disposable radiation shields were associated with lower operator, but not patient, radiation dose. © 2015 Wiley Periodicals, Inc.


Assuntos
Cateterismo Cardíaco/métodos , Alarmes Clínicos , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Exposição à Radiação/prevenção & controle , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Radiografia Intervencionista/métodos , Idoso , Cateterismo Cardíaco/efeitos adversos , Distribuição de Qui-Quadrado , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Exposição Ocupacional/efeitos adversos , Saúde do Trabalhador , Razão de Chances , Segurança do Paciente , Equipamento de Proteção Individual , Exposição à Radiação/efeitos adversos , Radiografia Intervencionista/efeitos adversos , Medição de Risco , Fatores de Risco , Texas , Fatores de Tempo
15.
Curr Opin Cardiol ; 30(5): 525-35, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26241710

RESUMO

PURPOSE OF REVIEW: Although antiplatelet agents are frequently prescribed to patients with lower extremity peripheral artery disease (PAD), there is an overall lack of consensus among published evidence and guidelines with respect to this practice. RECENT FINDINGS: Antiplatelet agents are prescribed to patients with PAD to reduce both cardiovascular and limb-based events during the follow-up period. A large evidence base supports the use of antiplatelet monotherapy with aspirin or clopidogrel in patients with symptomatic PAD or a history of peripheral artery revascularization. However, antiplatelet monotherapy has not proven beneficial in patients with asymptomatic PAD. Dual antiplatelet therapy has not demonstrated a clear benefit in reducing the risk of cardiovascular events in patients with symptomatic PAD. Its role in reducing the risk of adverse limb events following endovascular or surgical revascularization also remains unclear. Recently, the use of vorapaxar in addition to aspirin and/or clopidogrel has been associated with a significant reduction in the need for repeat revascularization procedures and hospitalization for limb ischemia in patients with established PAD. SUMMARY: Eligible patients with symptomatic PAD or with a history of peripheral artery revascularization should be prescribed antiplatelet monotherapy for secondary prevention of both cardiovascular and limb events, using aspirin, clopidogrel, and/or vorapaxar. Given the significant overlap of PAD and coronary artery disease, the evidence presented in this article may have important implications for management of patients with coronary artery disease.


Assuntos
Doença Arterial Periférica , Inibidores da Agregação Plaquetária , Trombose , Gerenciamento Clínico , Procedimentos Endovasculares/métodos , Humanos , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/complicações , Doença Arterial Periférica/terapia , Inibidores da Agregação Plaquetária/classificação , Inibidores da Agregação Plaquetária/farmacologia , Medição de Risco , Prevenção Secundária/métodos , Trombose/etiologia , Trombose/prevenção & controle
16.
Ann Vasc Surg ; 29(6): 1235-44, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26026491

RESUMO

BACKGROUND: The optimal dual-antiplatelet therapy (DAPT) duration after endovascular revascularization of infrainguinal arteries is uncertain. METHODS: This study examines DAPT prescription trends and 12-month major adverse limb events (MALEs; a composite of repeat endovascular or surgical revascularization, acute vessel thrombosis, or amputation of the target limb), major adverse cardiovascular events (MACEs; all-cause mortality, nonfatal myocardial infarction [MI], stroke, or coronary revascularization), fatal bleeding events, and those requiring interruption or discontinuation of DAPT (hemorrhagic complications) for patients enrolled into the Excellence in Peripheral Artery Disease (XLPAD) registry. RESULTS: Data on 368 patients prescribed antiplatelet therapy were analyzed; 8.2% were prescribed antiplatelet monotherapy, 48.6% DAPT for ≤3 months, and 43.2% for >3 months. Patients in the >3 DAPT prescribed group were older, had preexisting coronary artery disease (CAD), and prior MI (all P < 0.001). Overall MALE in the ≤3 and >3-month DAPT prescribed groups were 22.3% and 23.9%, respectively (P = 0.541). Survival analysis showed significantly higher rates of MACE in patients prescribed >3-month DAPT (17.6% vs. 9.5%; P = 0.019). An "as-treated" analysis excluded 10 patients who were prescribed DAPT for >3 months and revealed similar rates of MALE (24.9% vs. 20.8%; P = 0.386) and MACE (12.2% vs. 14.8%; P = 0.443) in patients receiving ≤3 and >3 DAPT. Hemorrhagic complications were similar across all prescribed and "as-treated" DAPT groups. CONCLUSIONS: After infrainguinal endovascular procedures, patients with underlying CAD were prescribed longer (>3 months) duration of DAPT and experienced more cardiovascular events compared with those prescribed ≤3 months of DAPT. Adverse limb events were similar in both groups.


Assuntos
Procedimentos Endovasculares , Doença Arterial Periférica/terapia , Inibidores da Agregação Plaquetária/administração & dosagem , Padrões de Prática Médica/tendências , Fatores Etários , Idoso , Amputação , Comorbidade , Intervalo Livre de Doença , Esquema de Medicação , Prescrições de Medicamentos , Quimioterapia Combinada , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Hemorragia/induzido quimicamente , Humanos , Estimativa de Kaplan-Meier , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Inibidores da Agregação Plaquetária/efeitos adversos , Modelos de Riscos Proporcionais , Recidiva , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
17.
J Endovasc Ther ; 22(4): 525-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25985785

RESUMO

PURPOSE: To compare success rates of a guidewire and microcatheter strategy vs the use of specialized crossing devices to traverse infrainguinal peripheral artery chronic total occlusions (CTOs). METHODS: For this analysis, data on 438 consecutive infrainguinal CTO interventions in 438 patients (mean age 63.2 years; 402 men) performed between August 2006 and May 2014 were extracted from the multicenter Excellence in Peripheral Artery Disease (XLPAD) database (ClinicalTrials.gov; identifier NCT01904851). Primary technical success constituted placement of a guidewire in the true lumen, past the distal CTO cap, with the initial crossing strategy. RESULTS: A wire-catheter strategy was used in 295 (67.4%) and a specialized CTO crossing device in 143 (32.6%) patients (p<0.001). Primary crossing technical success was higher with CTO devices (72.1% vs 51.9%, p<0.001). The primary wire-catheter arm used significantly more secondary CTO devices (28.1% vs 17.5%) and/or provisional re-entry devices (26.7% vs 4.9%) compared with the primary CTO device arm (both p<0.001). Secondary crossing technical success (defined as crossing with an alternate strategy: 67.5% vs 71.4%, p=1.000), provisional crossing technical success (defined as use of a re-entry device: 84.2% vs 87.5%, p=0.768), and procedure success (93.6% vs 90.9%, p=0.332) were similar between the wire-catheter and CTO device strategies, respectively. No differences were observed in periprocedural complications or 30-day adverse events; however, at 12 months, there was a significantly higher surgical revascularization rate in the primary wire-catheter arm (8.8% vs 2.8%, p=0.025). CONCLUSION: Infrainguinal peripheral artery CTO crossing is frequently attempted with a wire-catheter technique; however, an initial CTO crossing device approach is associated with higher primary technical success. Overall procedure success is similar with both strategies.


Assuntos
Arteriopatias Oclusivas/cirurgia , Perna (Membro)/irrigação sanguínea , Doenças Vasculares Periféricas/cirurgia , Dispositivos de Acesso Vascular , Angiografia , Anticoagulantes/administração & dosagem , Cateterismo , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
18.
Curr Cardiol Rep ; 17(5): 36, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25894799

RESUMO

Endovascular management of superficial femoral artery disease has historically been limited to percutaneous balloon angioplasty, atherectomy, and bare-metal stents. However, these therapies have been plagued by high restenosis and target lesion revascularization rates. More recent technologies such as drug-coated stents and balloons are designed to combat restenosis by locally delivering antiproliferative drugs. Several randomized controlled trials have directly compared these antiproliferative drug-delivering devices to their non-drug-coated counterparts. Additionally, trials are currently ongoing to compare use of drug-coated technologies in combination with traditional therapies in hope of synergistic effects. This review gathers data from currently published clinical trials, provides an overview of upcoming clinical studies utilizing drug-coated technology, and explores the possible impact these devices may have on clinical practice.


Assuntos
Angioplastia com Balão , Fármacos Cardiovasculares/administração & dosagem , Stents Farmacológicos , Artéria Femoral/cirurgia , Doença Arterial Periférica/terapia , Fármacos Cardiovasculares/classificação , Humanos , Extremidade Inferior , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Case Rep Vasc Med ; 2015: 157623, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25685591

RESUMO

Human Immunodeficiency Virus (HIV) infection and use of protease inhibitors have been associated with accelerated atherosclerosis. Increased rates of coronary in-stent restenosis are reported in these patients. There is limited data available on peripheral vascular disease interventions on these patients. Herein we report an aggressive subclavian in-stent restenosis with an unexpected response to balloon angioplasty treatment with a large, mobile tissue flap formation and its treatment with another stent.

20.
J Invasive Cardiol ; 27(1): 2-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25589693

RESUMO

BACKGROUND: Chronic total occlusions (CTOs) are reported in up to 40% of patients with symptomatic peripheral arterial disease. The Viance Crossing catheter (Covidien) and the CrossBoss catheter (Boston Scientific) are novel devices that facilitate either true lumen or subintimal navigation across CTOs. The purpose of this study was to examine the acute procedural success of these devices for popliteal and below-the-knee (BTK) CTOs. METHODS: Clinical and procedural outcome data between Sept 2010 and October 2013 were analyzed from the ongoing multicenter XLPAD registry. Technical success was defined as true lumen passage of the catheter, while procedural success was defined as successful vessel revascularization inclusive of subintimal passage and reentry. RESULTS: Twenty-nine patients underwent 31 procedures, in which 37 lesions were treated with the Viance and CrossBoss catheters. Mean age of the group was 69.1 ± 10.7 years and 26 patients were male (90%). All patients (100%) had hypertension, 62% were diabetic, and 48% were active smokers. Critical limb ischemia was the indication for the procedure in 58% of cases; mean Rutherford class was 4.2 ± 1.2 for the entire cohort. Target CTOs included 14 anterior tibial, 9 posterior tibial, 5 peroneal, 1 tibio-peroneal trunk, and 8 popliteal artery lesions. Mean lesion length was 81 ± 64 mm; 15 lesions (41%) were severely calcified. True lumen passage was obtained in 24 lesions (65% technical success). Subintimal entry was achieved in 5 lesions (14%). Procedural success was achieved in 26 lesions (70%). Procedural failure was related to longer lesion length (P<.001), and mean length of failed lesions was 136 ± 65 mm. CONCLUSION: Viance and CrossBoss catheters were associated with an overall 70% procedural success with predominantly true lumen crossing in a BTK-CTO cohort. CTO length remains an important determinant of device success.


Assuntos
Arteriopatias Oclusivas/cirurgia , Cateterismo Periférico , Artéria Poplítea , Dispositivos de Acesso Vascular , Idoso , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/fisiopatologia , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/instrumentação , Cateterismo Periférico/métodos , Pesquisa Comparativa da Efetividade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Poplítea/patologia , Artéria Poplítea/fisiopatologia , Artéria Poplítea/cirurgia , Sistema de Registros , Índice de Gravidade de Doença , Texas , Resultado do Tratamento , Grau de Desobstrução Vascular
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