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1.
ASAIO J ; 66(7): 734-738, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32597627

RESUMO

SARS-CoV-2 may cause severe respiratory failure due to massive alveolar damage. Currently, no adequate curative therapy for Coronavirus Disease 2019 (COVID-19) disease exists. By considering overall impact of COVID-19 pandemic outbreak, an increased need of extracorporeal membrane oxygenation (ECMO) support becomes evident. We report on our preliminary institutional experience with COVID-19 patients receiving venovenous ECMO support.


Assuntos
Betacoronavirus , Infecções por Coronavirus/terapia , Oxigenação por Membrana Extracorpórea , Pneumonia Viral/terapia , Síndrome do Desconforto Respiratório do Adulto/terapia , Adulto , Infecções por Coronavirus/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações
2.
Ann Thorac Surg ; 109(2): 505-511, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31381871

RESUMO

BACKGROUND: Since its introduction in 1992, multiple variations of the aortic valve-sparing David procedure technique have been described. Here, we present the short- and midterm outcomes of 2 centers using the straight tube graft (David-I) and the Valsalva prosthesis in patients who underwent isolated David procedure. METHODS: Between March 2002 and October 2015, 232 patients underwent the David procedure at 2 European centers. Patients received either a straight tube graft (David-I, group A, n = 103, 74% men) or Valsalva graft (group B, n = 129, 85% men). Mean age was 47 ± 17 years in group A and 48 ± 17 years in group B (P = .916). RESULTS: There were significantly more cusp repairs in group B (n=28, 22%) compared with group A (n = 4, 4%, P < .001). The 30-day mortality rate was 1% (n = 1) in group A and 2% (n = 2, P = .698) in group B. Postoperative echocardiography showed aortic insufficiency ≥II in 0% (n = 0) of group A and 17% (n = 21) of group B (P < .001). Follow-up comprised 1530 patient-years, and survival was comparable between the 2 groups (P = .799). Follow-up echocardiography showed aortic insufficiency ≥II in 22% (n = 15) of group A and 39% (n = 33) of group B (P < .026). The rates for aortic valve-related reoperation were 8% (n = 8) in group A and 13% (n = 16) in group B (P = .241). Logistic Cox regression analysis identified bicuspid aortic valve (odds ratio, 3.435; 95% confidence interval, 1.459-8.083, P = .005) and postoperative aortic insufficiency ≥II (odds ratio, 5.988; 95% confidence interval, 2.545-14.088, P < .001) as risk factors for aortic valve-related reoperation. CONCLUSIONS: The aortic valve-sparing David procedure has acceptable midterm results. Our results show that the David-I procedure with straight tube graft is not inferior to those performed with Valsalva prosthesis.


Assuntos
Aneurisma Aórtico/cirurgia , Prótese Vascular , Adulto , Valva Aórtica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodos
3.
Transplant Proc ; 51(9): 2962-2966, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31607616

RESUMO

INTRODUCTION: Preoperative liver and renal dysfunction remain surgical risk factors for both postoperative morbidity and mortality. The Model of End-Stage Liver Disease Excluding INR (international normalized ratio), or MELD-XI, score calculation may help as a predictor in patients with advanced heart failure. We analyzed the impact of progressive elevated MELD-XI values among recipients of heart transplant at our institution. METHODS: The data of a total of 425 consecutive adult patients who underwent heart transplantation, between January 2000 and August 2018, have been reviewed and divided into 3 cohorts according to preoperative MELD-XI calculations (MELD-XI < 11; MELD-XI 11-18; and MELD-XI > 18). Early and late outcomes have been analyzed. RESULTS: Patients with a MELD-XI score > 18 had a more critical clinical condition preoperatively and had a higher risk of early mortality (hazard ratio [HR] 1.45 [1.11-1.67], P < .001). They showed high risk for postoperative dialysis (HR 2.8 [1.5-5.3], P < .001), rethoracothomy for bleeding (HR 2.1 [1.2-4.1], P = .001), prolonged time of mechanical ventilation, time of intensive care unit stay (HR 2.2 [1.3-3.8], P = .005), and graft failure requiring mechanical circulatory support (HR 1.9 [1.1-3.3], P = .003). After risk adjustment per MELD-XI cohort, ischemic dilated cardiomyopathy, redo operation, and cold ischemic time > 240 minutes resulted in being the strongest predictors of early mortality (P < .001). The 5-year and 10-year survival for MELD-XI > 18 cohort was 63% and 47% vs 72% and 59% in the control group (MELD-XI < 18) (log-rank, P < .001). CONCLUSIONS: Patients with an elevated preoperative MELD-XI profile presented more comorbidities and significantly lower survival. This suggests the MELD-XI score may provide further insight into appropriate recipient and eventual donor selection. Renal insufficiency and congestive hepatopathy should be properly optimized before heart transplantation.


Assuntos
Doença Hepática Terminal/complicações , Transplante de Coração , Nefropatias/complicações , Índice de Gravidade de Doença , Adulto , Estudos de Coortes , Doença Hepática Terminal/mortalidade , Feminino , Transplante de Coração/mortalidade , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco
4.
Eur J Cardiothorac Surg ; 56(3): 564-571, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30932147

RESUMO

OBJECTIVES: We compared the results of 2 groups of patients who underwent aortic arch replacement with the frozen elephant trunk technique. In the first group, the distal anastomosis was performed in arch zone 2; in the second control group, the distal anastomosis was performed in arch zone 3. METHODS: Between January 2007 and April 2018, the frozen elephant trunk technique was used in 282 patients. The median age was 62 years (range 18-83 years), and 233 patients were men (82.6%). Two different frozen elephant trunk prostheses were used: the Jotec E-vita open prosthesis in 167 patients (59.2%) and the Vascutek Thoraflex hybrid prosthesis in 115 patients (40.8%). Patients were divided into 2 groups according to the distal anastomosis site: zone 2 group (69 patients) and zone 3 group (213 patients). The main indications were chronic aortic dissection (n = 164, 58.2%), degenerative aneurysm (n = 72, 25.5%) and acute aortic dissections (n = 45, 16%). RESULTS: The overall in-hospital mortality rate was 17%: 20% for the zone 2 group and 16% for the zone 3 group, without significant differences, also in terms of cardiopulmonary bypass and myocardial ischaemia times. However, the visceral ischaemia time was significantly shorter for the zone 2 group, whereas the antegrade selective cerebral perfusion time was significantly longer for the same group. Recurrent laryngeal nerve injury rate was lower in the zone 2 group. The overall postoperative paraplegia rate was 3.5%, whereas the occurrence of permanent neurological dysfunction and dialysis was 9% and 19%, respectively, with no significant differences between the groups. CONCLUSIONS: 'Proximalization' of the distal anastomosis can be used for arch reconstruction, especially in complex cases such as reoperations or acute aortic dissections. Furthermore, with the aid of branched hybrid grafts, a reduction of the visceral ischaemia time is achieved.

5.
J Vasc Surg ; 70(2): 432-437, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30922741

RESUMO

OBJECTIVE: The aim of this study was to describe single-center intraoperative details and early outcome of the new GORE TAG conformable stent graft with ACTIVE CONTROL (C-TAG ACTIVE CONTROL; W. L. Gore & Associates, Flagstaff, Ariz). METHODS: Between September 2017 and June 2018, a consecutive 30 patients underwent thoracic endovascular aortic repair with C-TAG ACTIVE CONTROL. This new system provides an intermediate deployment step at 50% and optional angulation control of the proximal part of the stent graft. Indications for thoracic endovascular aortic repair varied widely, including chronic postdissection and degenerative aneurysms, complicated acute dissections, and intramural hematomas, among others, in an elective (63.3%), urgent (13.3%), or emergent (23.3%) setting. The proximal landing zone (LZ) was LZ 2 in 23.3%, LZ 3 in 43.3%, and LZ 4 in 33.3%. Data were collected retrospectively and analyzed for technical and clinical success. RESULTS: In all patients, the stent graft was successfully introduced and deployed at the intended position, with complete exclusion of aortic disease and without intraoperative mortality (primary technical success, 100%). One emergent patient died at 2 days of ongoing septic shock (clinical success at 30 days, 96.6%). Median follow-up was 107 days (range, 33-271 days); late mortality was 3.4% (one patient died of stent graft infection at 40 days). Freedom from type I and type III endoleak at the early follow-up was 100%. No patients required other surgical or endovascular procedures for the primary treated aortic disease. CONCLUSIONS: Our reported initial experience in 30 patients with the C-TAG ACTIVE CONTROL showed excellent early results, with high deployment accuracy and conformability. The additional features of staged deployment and angulation control may be of great help in challenging aortic arch diseases, allowing precise positioning and preventing bird-beak effect.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Idoso , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/mortalidade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
6.
Int J Cardiol ; 271: 31-35, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30223362

RESUMO

BACKGROUND: Nowadays, less invasive endovascular procedures have been employed in high risk patients for thoracoabdominal aortic aneurysm (TAAA) in order to try to reduce the risk of major complications. The aim of the study was to analyze the results of our hybrid 2-stage approach for TAAA repair. METHODS: Between July 2011 and September 2016, 17 consecutive high-risk patients received a hybrid 2-stage procedure for TAAA repair. Mean age of the population was 58.9 ±â€¯9.0 years and 16 (94.1%) were male. Of them, 7 (41.2%) suffered of chronic obstructive pulmonary disease and 15 (88.2%) had a previous history of aortic operation. Three patients had Marfan syndrome (17.6%). The preoperative anatomy of the aneurysms was classified according to "Crawford classification" in type II (n = 6, 35.3%), type III (n = 10, 58.8%) and type IV (n = 1, 5.9%). All patients were followed up with an angio CT-scan at 1, 3 months and yearly thereafter. RESULTS: In-hospital mortality was 11.8% (2 patient). None of the patients experienced paraplegia and paraparesis. Major post-operative complications were pancreatitis 17.6% (3/17). At follow-up (mean time of 23.3 ±â€¯21.7 months) 2 patient died (12.5%) waiting for the second stage endovascular completion. Median interval time between the 2 steps was 35 days. Overall survival at 1- and 3-years was 75.6 ±â€¯1.0. One type Ib and 1 type III endoleak were noted and successfully treated with an additional stent graft. CONCLUSIONS: The results of hybrid 2-stage TAAA repair on high-risk patients are satisfactory and therefore encouraging. The extremely low incidence of spinal cord injury could make this technique the technique of choice for this type of pathology in selected high-risk patients. At follow-up, residual endoleaks occur although surgical reoperations are not often needed.


Assuntos
Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Procedimentos Endovasculares/métodos , Complicações Pós-Operatórias/prevenção & controle , Idoso , Implante de Prótese Vascular , Estudos de Coortes , Procedimentos Endovasculares/normas , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Stents/normas , Resultado do Tratamento , Grau de Desobstrução Vascular/fisiologia
8.
Nanotechnology ; 29(40): 405707, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30015624

RESUMO

Three-dimensional (3D) graphene-based architectures can combine the two-dimensional properties of graphene with the high surface-to-volume ratio required for a large variety of technological applications. We present a spectro-microscopy study of stable microporous 3D few-layer graphene structures with a very low density of defects/edges and of unsaturated bonds, as deduced by Raman and core level photoemission spectroscopy. These qualities make these interconnected graphene networks ideal candidates to accommodate lithium adatoms, with a high density of Li per unit volume and a Li uptake per C atom higher than the value observed for graphite, as confirmed by core level photoemission spectroscopy.

9.
Interact Cardiovasc Thorac Surg ; 27(6): 836-841, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29901810

RESUMO

OBJECTIVES: If mitral valve repair is not feasible, mitral valve replacement remains the only option. Based on our overall experience with the On-X mitral valve, the aim of this study was to investigate early and late outcomes after mitral valve replacement using this latest generation prosthesis. METHODS: From 1998 to 2016, 600 patients received an On-X prosthesis in the mitral position. Of them, we excluded all patients who had combined aortic procedures and retrospectively analysed 318 consecutive patients who had a mitral valve replacement. Associated procedures (53.5%) were tricuspid valve repair, coronary artery bypass graft and the maze procedure. The mean follow-up time was 5.6 ± 4.0 years. RESULTS: The overall hospital mortality rate was 4.4%, including acute cases of ischaemic mitral regurgitation (9.4%) and infective endocarditis (9.4%). Survival rates at 1, 3, 5 and 10 years were 97.8 ± 1.0%, 92.4 ± 1.7%, 88.4 ± 2.2% and 70.9 ± 4.0%, respectively. Independent predictors of late mortality were hypertension [hazard ratio (HR) 1.91; P = 0.027], chronic obstructive pulmonary disease (HR 2.91; P = 0.003) and chronic renal failure (HR 5.27; P < 0.001). Freedom from reoperation was 99.3 ± 0.5%, 98.4 ± 0.8%, 97.2 ± 1.2% and 92.5 ± 2.4% at 1, 3, 5 and 10 years, respectively. At follow-up, 8.5% events were recognized as thromboembolic or haemorrhagic events; freedom from events related to anticoagulation therapy at 1, 3, 5 and 10 years was 99.0 ± 0.6%, 96.8 ± 1.1%, 93.7 ± 1.8% and 89.0 ± 2.7%, respectively. CONCLUSIONS: According to the results of this observational study, the unique design of the On-X valve works well with mitral valve diseases of various aetiologies, especially in cases with an unfavourable anatomy. This prosthesis also guarantees safe long-term durability associated with a low incidence of thromboembolism.


Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Feminino , Mortalidade Hospitalar/tendências , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/mortalidade , Complicações Pós-Operatórias/epidemiologia , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Resultado do Tratamento
10.
ASAIO J ; 64(6): e140-e147, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29746312

RESUMO

Right ventricular failure after continuous-flow left ventricular assist device (LVAD) implantation is still an unsolved issue and remains a life-threatening event for patients. We undertook this study to determine predictors of the patients who are candidates for isolated LVAD therapy as opposed to biventricular support (BVAD). We reviewed demographic, echocardiographic, hemodynamic, and laboratory variables for 258 patients who underwent both isolated LVAD implantation and unplanned BVAD because of early right ventricular failure after LVAD insertion, between 2006 and 2017 (LVAD = 170 and BVAD = 88). The final study patients were randomly divided into derivation (79.8%, n = 206) and validation (20.1%, n = 52) cohorts. Fifty-seven preoperative risk factors were compared between patients who were successfully managed with an LVAD and those who required a BVAD. Nineteen variables demonstrated statistical significance on univariable analysis. Multivariable logistic regression analysis identified destination therapy (odds ratio [OR] 2.0 [1.7-3.9], p = 0.003), a pulmonary artery pulsatility index <2 (OR 3.3 [1.7-6.1], p = 0.001), a right ventricle/left ventricle end-diastolic diameter ratio >0.75 (OR 2.7 [1.5-5.5], p = 0.001), an right ventricle stroke work index <300 mm Hg/ml/m (OR 4.3 [2.5-7.3], p < 0.001), and a United Network for Organ Sharing modified Model for End-Stage Liver Disease Excluding INR score >17 (OR 3.5 [1.9-6.9], p < 0.001) as the major predictors of the need for BVAD. Using these data, we propose a simple risk calculator to determine the suitability of patients for isolated LVAD support in the era of continuous-flow mechanical circulatory support devices.


Assuntos
Coração Auxiliar/efeitos adversos , Disfunção Ventricular Direita/epidemiologia , Disfunção Ventricular Direita/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
11.
J Vis Surg ; 4: 77, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780723

RESUMO

Stroke events are very common in acute type A aortic dissection. Cerebral malperfusion could manifest at presentation due to prolonged arch vessels hypoperfusion or develop after surgery for inadequate cerebral protection during arch repair. To reduce this detrimental complication there are several adjuncts that can be adopted for cerebral protection such as direct antegrade or retrograde cerebral perfusion (RCP) and use period of deep to moderate hypothermic circulatory arrest time; however, they are often insufficient as preoperative malperfusion already caused irreversible ischemic damages. The aim of the current review article is to analyze the principal series reporting on neurological injuries during type A aortic dissection to focus on the outcomes according to the type of surgical management and identify possible predictors to better manage this complication.

12.
Nanotechnology ; 29(2): 025603, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29160237

RESUMO

This work investigates the growth of B-C-N layers by chemical vapor deposition using methylamine borane (MeAB) as the single-source precursor. MeAB has been synthesized and characterized, paying particular attention to the analysis of its thermolysis products, which are the gaseous precursors for B-C-N growth. Samples have been grown on Cu foils and transferred onto different substrates for their morphological, structural, chemical, electronic and optical characterizations. The results of these characterizations indicate a segregation of h-BN and graphene-like (Gr) domains. However, there is an important presence of B and N interactions with C at the Gr borders, and of C interacting at the h-BN-edges, respectively, in the obtained nano-layers. In particular, there is a significant presence of C-N bonds, at Gr/h-BN borders and in the form of N doping of Gr domains. The overall B:C:N contents in the layers is close to 1:3:1.5. A careful analysis of the optical bandgap determination of the obtained B-C-N layers is presented, discussed and compared with previous seminal works with samples of similar composition.

13.
J Chem Phys ; 147(21): 214706, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29221400

RESUMO

We report on the assembly of a highly ordered array of copper tetrameric clusters, coordinated into a metal-organic network. The ordered cluster array has been achieved by the deposition of tetrahydroxyquinone molecules on the Cu(111) surface at room temperature, and subsequent thermally activated dehydrogenation with the formation of tetraoxyquinone tetra-anions with a 4 × 4 periodicity. The supramolecular organic network acts as a spacer for the highly ordered two-dimensional network of copper tetramers at the very surface.

14.
Nanotechnology ; 28(11): 115601, 2017 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-28099157

RESUMO

Etching with atomic hydrogen, as a preparation step before the high-temperature growth process of graphene onto a thin 3C-SiC film grown on Si(111), greatly improves the structural quality of topmost graphene layers. Pit formation and island coalescence, which are typical of graphene growth by SiC graphitization, are quenched and accompanied by widening of the graphene domain sizes to hundreds of nanometers, and by a significant reduction in surface roughness down to a single substrate bilayer. The surface reconstructions expected for graphene and the underlying layer are shown with atomic resolution by scanning tunnelling microscopy. Spectroscopic features typical of graphene are measured by core-level photoemission and Raman spectroscopy.

15.
ACS Omega ; 2(7): 3691-3697, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457683

RESUMO

Scaling graphene from a two-dimensional (2D) ideal structure to a three-dimensional (3D) millimeter-sized architecture without compromising its remarkable electrical, optical, and thermal properties is currently a great challenge to overcome the limitations of integrating single graphene flakes into 3D devices. Herewith, highly connected and continuous nanoporous graphene (NPG) samples, with electronic and vibrational properties very similar to those of suspended graphene layers, are presented. We pinpoint the hallmarks of 2D ideal graphene scaled in these 3D porous architectures by combining the state-of-the-art spectromicroscopy and imaging techniques. The connected and bicontinuous topology, without frayed borders and edges and with low density of crystalline defects, has been unveiled via helium ion, Raman, and transmission electron microscopies down to the atomic scale. Most importantly, nanoscanning photoemission unravels a 3D NPG structure with preserved 2D electronic density of states (Dirac cone like) throughout the porous sample. Furthermore, the high spatial resolution brings to light the interrelationship between the topology and the morphology in the wrinkled and highly bent regions, where distorted sp2 C bonds, associated with sp3-like hybridization state, induce small energy gaps. This highly connected graphene structure with a 3D skeleton overcomes the limitations of small-sized individual graphene sheets and opens a new route for a plethora of applications of the 2D graphene properties in 3D devices.

16.
Nanotechnology ; 27(43): 435601, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27655270

RESUMO

High-temperature (1000 °C) thermolytic decomposition of ethane 1,2-diamineborane (BH3NH2CH2CH2NH2BH3) deposited onto a Cu foil has been performed in an ultra-high-vacuum environment. A combined thermolytic, structural (x-ray diffraction), microscopic (scanning electron microscopy) and spectroscopic (Raman, x-ray photoemission spectroscopy) analysis, has identified a ternary borocarbonitride (BCN) compound as a result of the process. The obtained BCN compound is nanocrystalline, surrounded by crystallites of ammonium hydroxide borate hydrate. The ternary compound presents a 0.2:0.6:0.2 B:C:N composition in the bulk and 0.11:0.76:0.13 stoichiometry at the very surface, richer in C-C networks with respect to the bulk. Furthermore, the resulting BCN compound does not show oxidation at the surface due to the in-vacuum thermolysis of the single precursor.

17.
Semin Thorac Cardiovasc Surg ; 27(3): 257-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26708365

RESUMO

Despite optimal hemodynamics at rest, the performance of the aortic valve under stress conditions long after David I procedure is still debated. From 2001-2014, 73 patients underwent reimplantation with David I technique. Aortic valve function of 13 patients (age 61.2 ± 8.72) with a follow-up of at least 5 years (6.3 ± 0.9 years) was assessed at exercise echocardiographic stress test on a stationary cycle. Patients who had undergone concomitant procedure, with recurrent aortic insufficiency or mitral valve incompetence, were excluded. In all, 8 healthy volunteers served as controls. Transvalvular gradients progressively increased during the steps in both groups (P-within < 0.001), being higher in David patients (P-between < 0.001), but never reaching a clinical significance (David Peak gradient 23.8 ± 9.3 mmHg; Mean gradient 13.2 ± 5.1 mmHg). Effective orifice area (EOA) and EOA index did not change during the test in David patients, whereas Controls showed a progressive increase of functional valve area to a peak at 50 W (Controls EOA 4.0 ± 0.5 cm(2); EOA index 2.0 ± 0.3 cm(2)/m(2)). In conclusion, David I procedure ensures good hemodynamics during high-flow conditions at long-term follow-up. The reimplantation of the functional aortic annulus inside a rigid tube determines a paradoxical reduction of functional aortic valve area, secondary to the increased stroke volume, without any clinically relevant increase in transvalvular gradients. These data confirm the reliability of David I in the long term, even under physical stress conditions.


Assuntos
Aorta Torácica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Ecocardiografia sob Estresse/métodos , Implante de Prótese de Valva Cardíaca/métodos , Hemodinâmica/fisiologia , Procedimentos Cirúrgicos Vasculares/métodos , Valva Aórtica/fisiopatologia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
18.
J Phys Chem Lett ; 6(9): 1690-5, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-26263335

RESUMO

A single layer of flat-lying iron phthalocyanine (FePc) molecules assembled on graphene grown on Ir(111) preserves the magnetic moment, as deduced by X-ray magnetic circular dichroism from the Fe L2,3 edges. Furthermore, the FePc molecules in contact with the graphene buffer layer exhibit an enhancement of the magnetic anisotropy, with emergence of an in-plane easy magnetic axis, reflected by an increased orbital moment of the FePc molecules in contact with the C atoms in the graphene sheet. The origin of the increased magnetic anisotropy is discussed, considering the absence of electronic state hybridization, and the breaking of symmetry upon FePc adsorption on graphene.

19.
J Cardiothorac Vasc Anesth ; 29(2): 275-82, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25791689

RESUMO

OBJECTIVES: The aim of this study was to evaluate the immediate and late outcome of emergency coronary artery bypass grafting (CABG) in a multicenter setting. DESIGN: Multicenter, retrospective study. SETTING: Four university hospitals. PARTICIPANTS: 596 patients were included in this study. INTERVENTIONS: Included patients underwent isolated, emergency CABG. MEASUREMENTS AND MAIN RESULTS: Sixty patients (absolute rate: 10.1%, pooled rate: 8.7%) died during the in-hospital stay period. Increasing emergency CABG classes (p<0.0001), recent myocardial infarction (p=0.019), left ventricular ejection fraction≤30% (p=0.034), on-pump surgery (p=0.012), and participating centers (p<0.0001) were independent predictors of in-hospital mortality. Survival rates at 1, 3, and 5 years were 86.4%, 81.6%, and 76.1%, respectively. Extracorporeal membrane oxygenation was used in 6 patients and 3 of them (50.0%) survived the immediate postoperative period. Patient populations of participating centers differed significantly in most of baseline characteristics. The preoperative use of intra-aortic balloon pump (8% to 51%) and off-pump surgery (2.8% to 56.3%) varied significantly between institutions. In-hospital mortality (2.8%, 5.9%, 7.7% and 19.8%, p<0.0001), as well as midterm survival, significantly differed between institutions (at 3 years, 90.6%, 89.8%, 81.2%, and 67.2%, p<0.0001). CONCLUSIONS: The outcome after emergency CABG is satisfactory despite a significant operative risk. However, the results of emergency CABG significantly differed between the participating institutions, likely due to differences in the referral pathways and perioperative treatment strategies. Evaluation of these factors is crucial for implementation of treatment in centers with suboptimal results.


Assuntos
Ponte de Artéria Coronária/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Idoso , Ponte de Artéria Coronária sem Circulação Extracorpórea/estatística & dados numéricos , Feminino , Finlândia/epidemiologia , Mortalidade Hospitalar , Humanos , Balão Intra-Aórtico/estatística & dados numéricos , Itália/epidemiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Estudos Retrospectivos , Taxa de Sobrevida
20.
Materials (Basel) ; 8(9): 5974-5985, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-28793545

RESUMO

Ethane 1,2-diamineborane (EDAB) is an alkyl-containing amine-borane adduct with improved hydrogen desorption properties as compared to ammonia borane. In this work, it is reported the high temperature thermolytic decomposition of EDAB. Thermolysis of EDAB has been investigated by concomitant thermogravimetry-differential thermal analysis-mass spectrometry experiments. EDAB shows up to four H2 desorption events below 1000 °C. Small fractions of CH4, C2H4 and CO/CO2 are also observed at moderate-high temperatures. The solid-state thermolysis product has been characterized by means of different structural and chemical methods, such as X-ray diffraction, Raman spectroscopy, Scanning electron microscopy, Elemental analysis, and X-ray photoelectron spectroscopy (XPS). The obtained results indicate the formation of a ternary borocarbonitride compound with a poorly-crystalline graphitic-like structure. By contrast, XPS measurements show that the surface is rich in carbon and nitrogen oxides, which is quite different to the bulk of the material.

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