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Catheter Cardiovasc Interv ; 97(1): 48-55, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31912983


OBJECTIVES: We sought to describe the outcomes of BVS use from a single-center experience in which scaffold implantation was guided by intravascular imaging (ultrasound and/or optical coherence tomography) to identify and treat mechanical factors potentially related to BVS failure. BACKGROUND: The Absorb bioresorbable vascular scaffold (BVS) has been associated with an unexpectedly high incidence of thrombosis. METHODS: Between 11/2014 and 10/2016, 100 patients were treated with BVS. Intravascular imaging assessment before and after BVS implantation was performed in all cases. RESULTS: Mean age was 58.1 years; 88% were male, 31% had diabetes, and 28% presented with acute coronary syndromes. A total of 171 lesions in 141 vessels were treated with 190 BVS (mean 1.9 scaffolds/patient). Further intervention following intravascular imaging to optimize BVS implantation was required in 31% of patients. Procedure success was 100%. All patients completed a 1-year follow-up. The 1-year rate of target lesion failure was 4%, and there were no cases (0%) of scaffold thrombosis, myocardial infarction, or death. CONCLUSIONS: In this real-world experience, the use of intravascular imaging to guide BVS implantation was associated with a high 1-year event-free survival rate, with no scaffold thrombosis.

Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Implantes Absorbibles , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Everolimus , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Diseño de Prótesis , Resultado del Tratamiento
Phys Rev E ; 102(6-1): 062133, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33466004


When a quantum system is subject to a thermal gradient it may sustain a steady nonequilibrium heat current by entering into a so-called nonequilibrium steady state (NESS). Here we show that NESS constitute a thermodynamic resource that can be exploited to charge a quantum battery. This adds to the list of recently reported sources available at the nanoscale, such as coherence, entanglement, and quantum measurements. We elucidate this concept by showing analytic and numerical studies of a two-qubit quantum battery that is alternatively charged by an incoherent heat flow and discharged by application of a properly chosen unitary gate. The presence of a NESS for the charging step guarantees steady operation with positive power output. Decreasing the duration of the charging step results in a time-periodic steady state accompanied by increased efficiency and output power. The device is amenable to implementation with different nanotechnology platforms.

Phys Rev Lett ; 119(19): 193603, 2017 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-29219533


The microscopic theory of superconductivity raised the disruptive idea that electrons couple through the elusive exchange of virtual phonons, overcoming the strong Coulomb repulsion to form Cooper pairs. Light is also known to interact with atomic vibrations, as, for example, in the Raman effect. We show that photon pairs exchange virtual vibrations in transparent media, leading to an effective photon-photon interaction identical to that for electrons in the BCS theory of superconductivity, in spite of the fact that photons are bosons. In this scenario, photons may exchange energy without matching a quantum of vibration of the medium. As a result, pair correlations for photons scattered away from the Raman resonances are expected to be enhanced. An experimental demonstration of this effect is provided here by time-correlated Raman measurements in different media. The experimental data confirm our theoretical interpretation of a photonic Cooper pairing, without the need for any fitting parameters.

Phys Rev Lett ; 117(24): 243603, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-28009217


Water is one of the most prevalent chemicals on our planet, an integral part of both our environment and our existence as a species. Yet it is also rich in anomalous behaviors. Here we reveal that water is a novel-yet ubiquitous-source for quantum correlated photon pairs at ambient conditions. The photon pairs are produced through Raman scattering, and the correlations arise from the shared quantum of a vibrational mode between the Stokes and anti-Stokes scattering events. We confirm the nonclassical nature of the produced photon pairs by showing that the cross-correlation and autocorrelations of the signals violate a Cauchy-Schwarz inequality by over 5 orders of magnitude. The unprecedented degree of violating the inequality in pure water, as well as the well-defined polarization properties of the photon pairs, points to its usefulness in quantum information.

Sci Rep ; 6: 33945, 2016 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-27669652


Memoryless time evolutions are ubiquitous in nature but often correspond to a resolution-induced approximation, i.e. there are correlations in time whose effects are undetectable. Recent advances in the dynamical control of small quantum systems provide the ideal scenario to probe some of these effects. Here we experimentally demonstrate the precise induction of memory effects on the evolution of a quantum coin (qubit) by correlations engineered in its environment. In particular, we design a collisional model in Nuclear Magnetic Resonance (NMR) and precisely control the strength of the effects by changing the degree of correlation in the environment and its time of interaction with the qubit. We also show how these effects can be hidden by the limited resolution of the measurements performed on the qubit. The experiment reinforces NMR as a test bed for the study of open quantum systems and the simulation of their classical counterparts.

Sci Rep ; 5: 17520, 2015 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-26627910


Non-Markovianity has recently attracted large interest due to significant advances in its characterization and its exploitation for quantum information processing. However, up to now, only non-Markovian regimes featuring environment to system backflow of information (strong non-Markovianity) have been experimentally simulated. In this work, using an all-optical setup we simulate and observe the so-called weak non-Markovian dynamics. Through full process tomography, we experimentally demonstrate that the dynamics of a qubit can be non-Markovian despite an always increasing correlation between the system and its environment which, in our case, denotes no information backflow. We also show the transition from the weak to the strong regime by changing a single parameter in the environmental state, leading us to a better understanding of the fundamental features of non-Markovianity.

Rev. bras. cardiol. invasiva ; 19(3): 286-291, set. 2011. tab
Artículo en Portugués | LILACS | ID: lil-607265


Introdução: Os stents farmacológicos (SFs) melhoraram a evolução clínica dos pacientes submetidos a intervenção coronária percutânea (ICP). Novos SFs foram desenvolvidos com o propósito de superar as atuais limitações da geração mais antiga de SFs. Este estudo teve como objetivo avaliar os aspectos angiográfico e ultrassonográfico tardios do SF eluidor de sirolimus FirebirdTM. Métodos: Entre dezembro de 2007 e março de 2008, 15 pacientes portadores de lesões de novo foram submetidos a ICP com implante de stent FirebirdTM. Avaliação com angiografia e USIC foi realizada em todos os pacientes aos 24 meses de seguimento. O objetivo primário foi a avaliação da perda luminal tardia à angiografia coronária quantitativa e o porcentual de obstrução volumétrica intrastent pelo ultrassom intracoronário (USIC) Resultados: A média de idade foi de 57 ± 7,1 anos, 87% eram do sexo masculino e 27% eram diabéticos. A artéria descendente anterior foi o vaso mais frequentemente tratado (36%) e a maioria das lesões era do tipo B2/C (82%). Aos 24 meses, a perda luminal tardia foi de 0,17 ± 0,36 mm e a revascularização do vaso tratado foi de 6,6%. O porcentual de obstrução volumétrica intrastent foi de 9,6 ± 4,6%. Não houve casos de óbito, infarto ou trombose de stent. Conclusões: Neste estudo de centro único brasileiro, o stent FirebirdTM apresentou resultados tardios satisfatórios. Esses achados, em conjunto com os disponíveis na literatura, fornecem evidências adicionais para o uso do stent FirebirdTM na prática clínica diária.

Humanos , Masculino , Femenino , Persona de Mediana Edad , Angioplastia/métodos , Angioplastia , Reestenosis Coronaria , Stents Liberadores de Fármacos , Stents Liberadores de Fármacos , Trombosis Coronaria/complicaciones , Trombosis Coronaria/diagnóstico , Ultrasonido , Aspirina/administración & dosificación , Heparina/administración & dosificación
Rev. bras. cardiol. invasiva ; 19(2): 153-159, jul. 2011. tab
Artículo en Portugués | LILACS | ID: lil-595228


Introdução: Recentemente a intervenção coronária percutânea (ICP) com stents farmacológicos (SFs) tem se mostrado uma opção viável em pacientes selecionados com lesão de tronco de coronária esquerda não-protegido (TCE-NP). Este estudo teve como objetivo avaliar a efetividade e a segurança da ICP com SFs em lesões de TCE-NP da prática diária, analisando a ocorrência combinada de eventos cardíacos adversos maiores (ECAM) a longo prazo. Métodos: Foram tratados 142 pacientes consecutivos, com média de seguimento clínico de 917 + 743 dias. A decisão de utilizar um ou dois stents e inibidor da glicoproteína IIb/IIIa ficou a critério do operador. Angiografia coronária no seguimento não foi realizada de rotina, mas deixada a critério clínico. Resultados: A média de idade foi de 67,5 + 16 anos, três quartos dos pacientes eram do sexo masculino, 29% eram portadores de diabetes e 39% apresentavam angina instável. Foram utilizados 2,75 + 1,25 stents por paciente. Lesões com comprometimento da bifurcação foram identificadas em 90,1% e as técnicas mais frequentemente utilizadas foram o provisional stent em 36% e o small crush em 29% dos pacientes. Ultrassom intracoronário foi realizado em 92,3% dos pacientes, e reintervenção ocorreu em 21,3% dos stents, por apresentarem aposição incompleta de suas hastes após o implante. ECAM na evolução tardia ocorreram em 15,4%, óbito cardíaco ocorreu em 3,6%, revascularização do vaso-alvo em 11,2% e trombose definitiva / provável do stent em 1,4%. Conclusões: A ICP com SFs em lesões de TCE-NP neste estudo mostrou ser segura e eficazna evolução tardia, com baixas taxas de óbito cardíaco e de trombose do stent.

Background: Recently, percutaneous coronary intervention (PCI) with drug-eluting stents (DES) has proven to be a feasible option in selected patients with unprotected left main (LM) disease. This study was aimed at assessing the efficacy and safety of PCI with DES in LM lesions in the daily practice, analyzing the long-term occurrence of major adverse cardiac events (MACE). Methods: A total of 142 consecutivepatients were treated with a mean follow-up of 917 + 743 days. The decision to use one or two stents or glycoprotein IIb/IIIa inhibitors was left to the operator’s discretion. Coronaryangiography was not performed routinely in the follow-up. Results: Mean age was 67.5 + 16 years, 75% of the patients were male, 29% had diabetes and 39% had unstable angina. A total of 2.75 + 1.25 stents were implanted per patient. Bifurcation lesions were identified in 90.1% and the most frequent techniques were the provisional stent in 36% and small crush in 29% of the patients. Intravascular ultrasound was performed in 92.3% of the patients and reinterventions in 21.3% of the stents due to incomplete appositionof the struts after implantation. In the late follow-up, MACE was observed in 15.4% of the patients, cardiac deathin 3.6%, target-vessel revascularization in 11.2% and definitive/probably stent thrombosis in 1.4%. Conclusions: In thisstudy, PCI with DES proved to be safe and effective in the late follow-up of LM lesions, with low cardiac death and stentthrombosis rates.

Humanos , Masculino , Femenino , Anciano , Angioplastia/métodos , Angioplastia , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Infarto del Miocardio/complicaciones , Infarto del Miocardio/mortalidad , Stents Liberadores de Fármacos , Aspirina/administración & dosificación , Stents
Rev. bras. cardiol. invasiva ; 17(4): 545-548, out.-dez. 2009. ilus
Artículo en Portugués | LILACS | ID: lil-543389


Relatamos o caso de um paciente com reestenose de stent não-farmacológico, secundária a hipoexpansão da prótese, decorrente de grave calcificação da placa aterosclerótica subjacente, a qual não foi adequadamente reconhecida na angiografia. A utilização do ultrassom intracoronário foi de grande importância para reconhecer o mecanismo da reestenose e orientar na escolha da estratégia intervencionista mais adequada. A aterectomia rotacional foi realizada com sucesso para debilitar o cálcio peristent, permitindo a expansão posterior da prótese com balões de alta pressão.

Humanos , Masculino , Persona de Mediana Edad , Calcinosis , Reestenosis Coronaria , Enfermedad Coronaria , Angioplastia , Stents