Determination of the surface temperature of magnetically heated nanoparticles using a catalytic approach.

Herein we describe a new method for the determination of the surface temperature of magnetically heated nanoparticles in solution using the temperature dependency of the catalytic performances of iron carbide nanoparticles coated with ruthenium (Fe2.2C@Ru) for acetophenone hydrodeoxygenation. A correlation between nanoparticle surface temperature and magnetic field could be established. Very high surface temperatures could be estimated in different solvents, which were also found similar at a given magnetic field and well above some solvent boiling points.

Bimetallic Nanoparticles Associating Noble Metals and First-Row Transition Metals in Catalysis.

Bimetallic nanoparticles (NPs) are complex systems with properties that far exceed those of the individual constituents. In particular, association of a noble metal and a first-row transition metal are attracting increasing interest for applications in catalysis, electrocatalysis, and magnetism, among others. Such objects display a rich structural chemistry thanks to their ability to form intermetallic phases, random alloys, or core-shell species. However, under reaction conditions, the surface of these nanostructures may be modified due to migration, segregation, or isolation of single atoms, leading to the formation of original structures with enhanced catalytic activity. In this respect, Zakhtser et al. report in this issue of ACS Nano the synthesis and study of the chemical evolution of the surface of a series of PtZn nanostructured alloys. In this Perspective, we report some selected examples of bimetallic nanocatalysts and their increased activity compared to that of the corresponding pure noble metal, with a special focus on Pt-based systems. We also discuss the mobility of the species present on the catalyst surface and the electronic influence of one metal to the other.

Ultrastable Magnetic Nanoparticles Encapsulated in Carbon for Magnetically Induced Catalysis.

Magnetically induced catalysis using magnetic nanoparticles (MagNPs) as heating agents is a new efficient method to perform reactions at high temperatures. However, the main limitation is the lack of stability of the catalysts operating in such harsh conditions. Normally, above 500 °C, significant sintering of MagNPs takes place. Here we present encapsulated magnetic FeCo and Co NPs in carbon (Co@C and FeCo@C) as an ultrastable heating material suitable for high-temperature magnetic catalysis. Indeed, FeCo@C or a mixture of FeCo@C:Co@C (2:1) decorated with Ni or Pt-Sn showed good stability in terms of temperature and catalytic performances. In addition, consistent conversions and selectivities regarding conventional heating were observed for CO2 methanation (Sabatier reaction), propane dehydrogenation (PDH), and propane dry reforming (PDR). Thus, the encapsulation of MagNPs in carbon constitutes a major advance in the development of stable catalysts for high-temperature magnetically induced catalysis.

Chemoselective H/D exchange catalyzed by nickel nanoparticles stabilized by N-heterocyclic carbene ligands.

With this work, we report the synthesis and full characterization of nickel nanoparticles (NPs) stabilized by N-heterocyclic carbene (NHC) ligands, namely 1,3-bis(cyclohexyl)-1,3-dihydro-2H-imidazol-2-ylidene (ICy) and 1,3-bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene (IMes). Although the resulting NPs have the same size, they display different magnetic properties and different reactivities, which result from ligand effects. In the context of H/D exchange on pharmaceutically relevant heterocycles, Ni@NHC shows a high chemoselectivity, avoiding the formation of undesired reduced side-products and enabling a variety of H/D exchange on nitrogen-containing aromatic compounds. Using 2-phenylpyridine as a model substrate, it was observed that deuteration occurred preferably at the α position of the nitrogen atom, which is the most accessible position for the C-H activation. In addition, Ni@IMes NPs are also able to fully deuterate the ortho positions of the phenyl substituents.

Magnetically Induced CO2 Methanation Using Exchange-Coupled Spinel Ferrites in Cuboctahedron-Shaped Nanocrystals.

Magnetically induced catalysis can be promoted taking advantage of optimal heating properties from the magnetic nanoparticles to be employed. However, when unprotected, these heating agents that are usually air-sensitive, get sintered under the harsh catalytic conditions. In this context, we present, to the best of our knowledge, the first example of air-stable magnetic nanoparticles that: 1) show excellent performance as heating agents in the CO2 methanation catalyzed by Ni/SiRAlOx, with CH4 yields above 95 %, and 2) do not sinter under reaction conditions. To attain both characteristics we demonstrate, first the exchange-coupled magnetic approach as an alternative and effective way to tune the magnetic response and heating efficiency, and second, the chemical stability of cuboctahedron-shaped core-shell hard CoFe2 O4 -soft Fe3 O4 nanoparticles.

Engineering Iron-Nickel Nanoparticles for Magnetically Induced CO2 Methanation in Continuous Flow.

Induction heating of magnetic nanoparticles (NPs) is a method to activate heterogeneous catalytic reactions. It requires nano-objects displaying high heating power and excellent catalytic activity. Here, using a surface engineering approach, bimetallic NPs are used for magnetically induced CO2 methanation, acting both as heating agent and catalyst. The organometallic synthesis of Fe30 Ni70 NPs displaying high heating powers at low magnetic field amplitudes is described. The NPs are active but only slightly selective for CH4 after deposition on SiRAlOx owing to an iron-rich shell (25 mL min-1 , 25 mT, 300 kHz, conversion 71 %, methane selectivity 65 %). Proper surface engineering consisting of depositing a thin Ni layer leads to Fe30 Ni70 @Ni NPs displaying a very high activity for CO2 hydrogenation and a full selectivity. A quantitative yield in methane is obtained at low magnetic field and mild conditions (25 mL min-1 , 19 mT, 300 kHz, conversion 100 %, methane selectivity 100 %).

σ-H-H, σ-C-H, and σ-Si-H Bond Activation Catalyzed by Metal Nanoparticles.

Activation of H-H, Si-H, and C-H bonds through σ-bond coordination has grown in the past 30 years from a scientific curiosity to an important tool in the functionalization of hydrocarbons. Several mechanisms were discovered via which the initially σ-bonded substrate could be converted: oxidative addition, heterolytic cleavage, σ-bond metathesis, electrophilic attack, etc. The use of metal nanoparticles (NPs) in this area is a more recent development, but obviously nanoparticles offer a much richer basis than classical homogeneous and heterogeneous catalysts for tuning reactivity for such a demanding process as C-H functionalization. Here, we will review the surface chemistry of nanoparticles and catalytic reactions occurring in the liquid phase, catalyzed by either colloidal or supported metal NPs. We consider nanoparticles prepared in solution, which are stabilized and tuned by polymers, ligands, and supports. The question we have addressed concerns the differences and similarities between molecular complexes and metal NPs in their reactivity toward σ-bond activation and functionalization.

Hydrodeoxygenation Using Magnetic Induction: High-Temperature Heterogeneous Catalysis in Solution.

Magnetic heating has recently been demonstrated as an efficient way to perform catalytic reactions after deposition of the heating agent and the catalyst on a support. Here we show that in solution, and under mild conditions of mean temperature and pressure, it is possible to use magnetic heating to carry out transformations that are otherwise performed heterogeneously at high pressure and/or high temperature. As a proof of concept, we chose the hydrodeoxygenation of acetophenone derivatives and of biomass-derived molecules, namely furfural and hydroxymethylfurfural. These reactions are difficult, require heterogeneous catalysts and high pressures, and, to the best of our knowledge, have no precedent in standard solution. Here, hydrodeoxygenations are fully selective under mild conditions (3 bar H2 , moderate mean temperature of the solvent). The reason for this reactivity is the fast heating of the particles well above the boiling temperature of the solvent and the local creation of hot spots surrounded by a vapor layer, in which high temperature and pressure may be present. This technology may be practicable for many organic transformations.

Reducción de eventos a largo plazo tras el cierre de la orejuela izquierda. Resultados del Registro Ibérico II / Long-term event reduction after left atrial appendage closure. Results of the Iberian Registry II

Introducción y objetivos: Muchos pacientes con fibrilación auricular no valvular tienen contraindicados los anticoagulantes orales. El objetivo es estimar la incidencia de eventos tromboembólicos y hemorrágicos en pacientes con fibrilación auricular no valvular y cierre de la orejuela izquierda con seguimiento a largo plazo, y determinar los factores asociados con mayor mortalidad a largo plazo. Métodos: Cohorte prospectiva de pacientes reclutados desde 2009 a 2015. Se compararon los eventos tromboembólicos y hemorrágicos con los esperados según las escalas CHA2DS2-VASc y HAS-BLED. Se realizó un análisis multivariable para determinar las variables asociadas con la mortalidad. Resultados: Se reclutó a 598 pacientes (1.093 pacientes-año) con contraindicación de anticoagulantes (mediana de edad, 75,4 años). La tasa de éxito del cierre de la orejuela izquierda fue del 95,8%; 30 pacientes (5%) presentaron complicaciones. Las tasas de eventos (cada 100 pacientes-año) durante el seguimiento (media, 22,9 meses; mediana, 16,1 meses) fueron: muerte, 7,0%; ictus isquémico, 1,6% (frente al 8,5% esperado según CHA2DS2-VASc; p < 0,001); hemorragia intracraneal, 0,8%; hemorragia gastrointestinal, 3,2%, y hemorragia grave, 3,9% (frente al 6,3% esperado por HAS-BLED; p = 0,002). Estos resultados incluso mejoraron en el subgrupo de 176 pacientes con seguimiento > 24 meses (media, 46,6 meses; 683 pacientes-año) para las hemorragias graves, el 2,6% (frente al 6,3% esperado por HAS-BLED; p < 0,033). La edad (HR = 1,1), las hemorragias intracraneales (HR = 6,8) y el ictus (HR = 2,7) se asociaron con mayor mortalidad. Conclusiones: El cierre de la orejuela izquierda redujo significativamente las incidencias de ictus y de eventos hemorrágicos graves y el beneficio se mantuvo. La edad, las hemorragias intracraneales y el ictus se asociaron con mayor mortalidad

Introduction and objectives: Many patients with nonvalvular atrial fibrillation are still left without protection due to a contraindication for anticoagulants. This study aimed to establish the occurrence of stroke and major bleeding events in patients with nonvalvular atrial fibrillation and left atrial appendage closure with long-term follow-up and to explore the factors associated with higher long-term mortality. Methods: Analysis of a multicenter single cohort prospectively recruited from 2009 to 2015. Thromboembolic and bleeding events were compared with those expected from CHA2DS2-VASc and HAS-BLED scores. Multivariate analysis examined variables associated with mortality during follow-up. Results: A total of 598 patients (1093 patient-years) with a contraindication for anticoagulants were recruited (median 75.4 years). The success rate of left atrial appendage closure device implantation was 95.8%. Thirty patients (5%) experienced periprocedural complications. The rate of events (per 100 patient-years) during follow-up (mean 22.9 months; median 16.1 months) was as follows: death 7.0%; ischemic stroke 1.6% (vs 8.5% expected according to CHA2DS2-VASc; P < .001); intracranial hemorrhage 0.8%; gastrointestinal bleeding 3.2%; severe bleeding 3.9% (vs 6.3% expected by HAS-BLED, P = .002). These results were improved in the subgroup of 176 patients with follow-up > 24 months (mean follow-up 46.6 months, 683 patient-years) for severe bleeding 2.6% (vs 6.3% expected by HAS-BLED, P < .033). The factors significantly associated with higher mortality were age (HR, 1.1), intracranial hemorrhage (HR, 6.8), and stroke during follow-up (HR, 2.7). Conclusions: Left atrial appendage closure significantly reduced the incidence of stroke and bleeding events and the benefit was maintained. Intracranial hemorrhage, age and stroke were associated with higher mortality

Water-Dispersible and Biocompatible Iron Carbide Nanoparticles with High Specific Absorption Rate.

Magnetic nanoparticles are important tools for biomedicine, where they serve as versatile multifunctional instruments for a wide range of applications. Among these applications, magnetic hyperthermia is of special interest for the destruction of tumors and triggering of drug delivery. However, many applications of magnetic nanoparticles require high-quality magnetic nanoparticles displaying high specific absorption rates (SARs), which remains a challenge today. We report here the functionalization and stabilization in aqueous media of highly magnetic 15 nm iron carbide nanoparticles featuring excellent heating power through magnetic induction. The challenge of achieving water solubility and colloidal stability was addressed by designing and using specific dopamine-based ligands. The resulting nanoparticles were completely stable for several months in water, phosphate, phosphate-buffered saline, and serum-containing media. Iron carbide nanoparticles displayed high SARs in water and viscous media (water/glycerol mixtures), even after extended exposition to water and oxygen (SAR up to 1000 W·g-1 in water at 100 kHz, 47 mT). The cytotoxicity and cellular uptake of iron carbide nanoparticles could be easily tuned and were highly dependent on the chemical structure of the ligands used.

To heat or not to heat: a study of the performances of iron carbide nanoparticles in magnetic heating.

Heating magnetic nanoparticles with high frequency magnetic fields is a topic of interest for biological applications (magnetic hyperthermia) as well as for heterogeneous catalysis. This study shows why FeC NPs of similar structures and static magnetic properties display radically different heating power (SAR from 0 to 2 kW g-1). By combining results from Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS) and static and time-dependent high-frequency magnetic measurements, we propose a model describing the heating mechanism in FeC nanoparticles. Using, for the first time, time-dependent high-frequency hysteresis loop measurements, it is shown that in the samples displaying the larger heating powers, the hysteresis is strongly time dependent. More precisely, the hysteresis area increases by a factor 10 on a timescale of a few tens of seconds. This effect is directly related to the ability of the nanoparticles to form chains under magnetic excitation, which depends on the presence or not of strong dipolar couplings. These differences are due to different ligand concentrations on the surface of the particles. As a result, this study allows the design of a scalable synthesis of nanomaterials displaying a controllable and reproducible SAR.

Long-term Event Reduction After Left Atrial Appendage Closure. Results of the Iberian Registry II.

INTRODUCTION AND OBJECTIVES: Many patients with nonvalvular atrial fibrillation are still left without protection due to a contraindication for anticoagulants. This study aimed to establish the occurrence of stroke and major bleeding events in patients with nonvalvular atrial fibrillation and left atrial appendage closure with long-term follow-up and to explore the factors associated with higher long-term mortality. METHODS: Analysis of a multicenter single cohort prospectively recruited from 2009 to 2015. Thromboembolic and bleeding events were compared with those expected from CHA2DS2-VASc and HAS-BLED scores. Multivariate analysis examined variables associated with mortality during follow-up. RESULTS: A total of 598 patients (1093 patient-years) with a contraindication for anticoagulants were recruited (median 75.4 years). The success rate of left atrial appendage closure device implantation was 95.8%. Thirty patients (5%) experienced periprocedural complications. The rate of events (per 100 patient-years) during follow-up (mean 22.9 months; median 16.1 months) was as follows: death 7.0%; ischemic stroke 1.6% (vs 8.5% expected according to CHA2DS2-VASc; P < .001); intracranial hemorrhage 0.8%; gastrointestinal bleeding 3.2%; severe bleeding 3.9% (vs 6.3% expected by HAS-BLED, P = .002). These results were improved in the subgroup of 176 patients with follow-up > 24 months (mean follow-up 46.6 months, 683 patient-years) for severe bleeding 2.6% (vs 6.3% expected by HAS-BLED, P < .033). The factors significantly associated with higher mortality were age (HR, 1.1), intracranial hemorrhage (HR, 6.8), and stroke during follow-up (HR, 2.7). CONCLUSIONS: Left atrial appendage closure significantly reduced the incidence of stroke and bleeding events and the benefit was maintained. Intracranial hemorrhage, age and stroke were associated with higher mortality.

TIOMAX: A Spanish Multicenter Registry of the real-world use of the TItanium OptiMAX® biostent: TIOMAX: Registro Español Multicéntrico Del Biostent De Titanio OptiMAX® En La Vida Real.

OBJECTIVES: To compare the safety and efficacy of the new cobalt-chromium bioactive stent Titan Optimax® (Hexacath, France) with its predecessor, Titan-2® . BACKGROUND: The TIOMAX registry includes 784 patients who underwent percutaneous coronary intervention with these stents in 21 Spanish hospitals. METHODS: Analysis of all patients in the registry without exclusion criteria, candidates for revascularization (March-2013/July-2014). Initially 273 patients received Titan-2® , and the next 511 received the Optimax® after its launch. RESULTS: Mean age was 65.8 ± 13.0 (78.1% men); 49.2% were STEACS patients (n = 322), 29.8% NSTEACS, and 27.3% had stable angina or silent ischemia. Most STEACS patients (76.4% of n = 322) were treated <24 hr after developing symptoms. All-cause death (D), cardiac death (CD), acute myocardial infarction (AMI), and stent thrombosis (ST) at 1 month were 1.1, 0.8, 0.1, and 0.5%, respectively, with no significant differences between groups. At 1 year, the death rate was 5.5% for Titan-2 vs. 4.1% for Optimax® , CD was 1.8% for both groups, ST 1.1 vs. 0.6%, new AMI 3.3 vs. 2.5% and target lesion revascularization (TLR) 3.7 vs. 2.9%. The primary endpoint of the composite event (CE) of D/AMI/TLR/ST occurred in 10.3% vs. 7.6% (p = 0.211). Patients with STEACS (N = 322: Titan-2/Optimax: 103/209) had better outcomes for secondary events, device-oriented failure CD/AMI/TLR (7.8% vs. 5.0%; p = 0.330), and non-fatal CE of AMI/ST/TLR (7.8% vs. 2.7%, p = 0.039). CONCLUSIONS: The Titan Optimax retains the efficacy and safety of Titan 2. It appears to perform better in the subgroup of STEACS patients, by reducing the non-fatal CE of AMI/ST/TLR.

Synthesis of Water-Soluble Palladium Nanoparticles Stabilized by Sulfonated N-Heterocyclic Carbenes.

A strategy involving the decomposition of palladium(II) organometallic complexes with sulfonated N-heterocyclic carbene ligands leads to the formation of stable and water-soluble Pd nanoparticles. Three different methodologies (thermal decomposition, reduction under 13 CO atmosphere, and reduction with H2 ) gave particles with different shapes and sizes, ranging from 1.5 to 7 nm. The structures of the organometallic intermediates and organic decomposition products were elucidated by NMR spectroscopy. To check the accessibility of the surface, the nanoparticles were tested as catalysts for the chemoselective hydrogenation of styrene in water. An effect of the particle size on the catalyst activity was observed. The aqueous phase was recycled up to ten times without any precipitation of metallic palladium.

Synthesis of water-soluble palladium(ii) complexes with N-heterocyclic carbene chelate ligands and their use in the aerobic oxidation of 1-phenylethanol.

The synthesis of palladium(ii) complexes containing N-heterocyclic carbene chelate ligands is reported. These chelate ligands have methylene or ethylene ring bridges and sulfonate, carbonate or ammonium functionalities to render the complexes soluble in water. Bis- [(bis-NHC)PdX2] (X = Cl, Br or I) and tetra-carbene [(bis-NHC)2Pd] complexes have been prepared and the crystal structures of two of them have been determined. The NHC ligand is coordinated to the metal center in normal (C2-bound) or abnormal (C4-bound) mode. Processes involving the formation of NHC-Pd bonds or the transfer of NHC ligands have been explored in water. The behavior of the bis-carbene complexes as catalysts for the aerobic oxidation of 1-phenylethanol is also discussed.

Knight Shift in 13 C†NMR Resonances Confirms the Coordination of N-Heterocyclic Carbene Ligands to Water-Soluble Palladium Nanoparticles.

The coordination of N-heterocyclic carbene (NHC) ligands to the surface of 3.7 nm palladium nanoparticles (PdNPs) can be unambiguously established by observation of Knight shift (KS) in the 13 C resonance of the carbenic carbon. In order to validate this coordination, PdNPs with sizes ranging from 1.3 to 4.8 nm were prepared by thermal decomposition or reduction with CO of a dimethyl NHC PdII complex. NMR studies after 13 CO adsorption established that the KS shifts the 13 C resonances of the chemisorbed molecules several hundreds of ppm to high frequencies only when the particle exceeds a critical size of around 2 nm. Finally, the resonance of a carbenic carbon is reported to be Knight-shifted to 600 ppm for 13 C-labelled NHCs bound to PdNPs of 3.7 nm. The observation of these very broad KS resonances was facilitated by using Car-Purcell-Meiboom-Gill (CPMG) echo train acquisition NMR experiments.

Estudio aleatorizado para comparar el stentbioactivo de titanio con el stent de everolimus en pacientes diabéticos (TITANIC XV), resultados a 1 año / A Randomized Study to Compare Bioactive Titanium Stents and Everolimus-eluting Stents in Diabetic Patients (TITANIC XV): 1-year Results

Introducción y objetivos Hasta un 25% de los pacientes sometidos a intervencionismo coronario percutáneo presentan alguna limitación para la utilización de los stents farmacoactivos. Nuestro objetivo es evaluar si el stent bioactivo de titanio y óxido nítrico podía ser una buena alternativa al stent de everolimus para pacientes diabéticos.MétodosSe aleatorizó a 173 pacientes diabéticos con lesiones de riesgo de reestenosis intermedio (criterios de exclusión: diámetro < 2,5 mm o longitud > 28 mm en vasos < 3 mm, oclusión crónica): 83 pacientes en el grupo con titanio y 90 en el grupo con everolimus.ResultadosLas variables basales estaban bien equilibradas, el 28,3% eran insulinodependientes. Al año, las incidencias de eventos adversos cardiacos mayores (muerte, infarto de miocardio no fatal, ictus o nueva revascularización del vaso tratado) eran significativamente más frecuente en el grupo con titanio que en el grupo con everolimus (total, el 14,5 frente al 4,4%; p = 0,02; subgrupo no insulinodependiente, el 9,7 frente al 3,2%; p = 0,14; insulinodependiente, el 28,6 frente al 7,1%; p = 0,04) y de muerte, infarto de miocardio no fatal, ictus o cualquier revascularización, del 16,9% en el grupo con titanio y el 7,8% en el grupo con everolimus (p = 0,06). La revascularización de la lesión diana se produjo en el 8,4 frente al 3,3% (p = 0,15), y la del vaso tratado, el 13,3 frente al 3,3% (p = 0,01). El seguimiento angiográfico a 9 meses mostró una pérdida luminal tardía significativamente menor en el grupo con everolimus (en el segmento, 0,52 ± 0,58 frente a -0,05 ± 0,32 mm; en el stent, 0,76 ± 0,54 frente a 0,13 ± 0,31 mm; p < 0,0001). ConclusionesEl stent de everolimus fue superior al titanio en pacientes diabéticos incluso con lesiones de riesgo de eventos clínicos y angiográficos intermedio (AU)

Introduction and objectives Up to 25% of patients who undergo a percutaneous coronary intervention show some limitation in the use of drug-eluting stents. The aim of this study was to evaluate if titanium-nitride-oxide-coated stents could be a good alternative to everolimus-eluting stents in diabetic patients.MethodsA total of 173 diabetic patients with lesions at moderate risk of restenosis (exclusion criteria: diameter < 2.5 mm or length > 28 mm in vessels < 3 mm, chronic occlusion) were randomized to a titanium group (83 patients) or an everolimus group (90 patients).ResultsBaseline characteristics were well balanced; 28.3% of patients were insulin dependent. At 1 year, the incidence of major adverse cardiac events (death, nonfatal myocardial infarction, stroke, or repeat target vessel revascularization) was significantly higher in the titanium group than in the everolimus group (total, 14.5% vs 4.4%; P = .02; noninsulin-dependent subgroup, 9.7% vs 3.2%; P = .14; insulin-dependent subgroup, 28.6% vs 7.1%; P = .04). The incidence of death, nonfatal myocardial infarction, stroke, or any revascularization was 16.9% in the titanium group and 7.8% in the everolimus group (P = .06). Target lesion and vessel revascularizations occurred in 8.4% compared with 3.3% (P = .15) and in 13.3% compared with 3.3% (P = .01) in the titanium and everolimus groups, respectively. Angiographic follow-up at 9 months showed significantly less late lumen loss in the everolimus group (in-segment, 0.52 [standard deviation, 0.58) mm vs -0.05 [0.32] mm; in-stent, 0.76 [0.54] mm vs 0.13 [0.31] mm; P < .0001).ConclusionsThe everolimus-eluting stent is superior to the titanium stent for clinical and angiographic end points in diabetic patients with lesions at moderate risk of restenosis (AU)

A randomized study to compare bioactive titanium stents and everolimus-eluting stents in diabetic patients (TITANIC XV): 1-year results.

INTRODUCTION AND OBJECTIVES: Up to 25% of patients who undergo a percutaneous coronary intervention show some limitation in the use of drug-eluting stents. The aim of this study was to evaluate if titanium-nitride-oxide-coated stents could be a good alternative to everolimus-eluting stents in diabetic patients. METHODS: A total of 173 diabetic patients with lesions at moderate risk of restenosis (exclusion criteria: diameter < 2.5 mm or length > 28 mm in vessels < 3mm, chronic occlusion) were randomized to a titanium group (83 patients) or an everolimus group (90 patients). RESULTS: Baseline characteristics were well balanced; 28.3% of patients were insulin dependent. At 1 year, the incidence of major adverse cardiac events (death, nonfatal myocardial infarction, stroke, or repeat target vessel revascularization) was significantly higher in the titanium group than in the everolimus group (total, 14.5% vs 4.4%; P = .02; noninsulin-dependent subgroup, 9.7% vs 3.2%; P = .14; insulin-dependent subgroup, 28.6% vs 7.1%; P = .04). The incidence of death, nonfatal myocardial infarction, stroke, or any revascularization was 16.9% in the titanium group and 7.8% in the everolimus group (P = .06). Target lesion and vessel revascularizations occurred in 8.4% compared with 3.3% (P = .15) and in 13.3% compared with 3.3% (P = .01) in the titanium and everolimus groups, respectively. Angiographic follow-up at 9 months showed significantly less late lumen loss in the everolimus group (in-segment, 0.52 [standard deviation, 0.58) mm vs -0.05 [0.32] mm; in-stent, 0.76 [0.54] mm vs 0.13 [0.31] mm; P < .0001). CONCLUSIONS: The everolimus-eluting stent is superior to the titanium stent for clinical and angiographic end points in diabetic patients with lesions at moderate risk of restenosis.

Anatomical classification of left atrial appendages in specimens applicable to CT imaging techniques for implantation of amplatzer cardiac plug.

BACKGROUND: Certain anatomical characteristics of the left atrial appendage (LAA) are associated with complexity in the implantation of occluder devices. OBJECTIVE: The aim was to define characteristics measurable by three-dimensional imaging that would predict complexities both in the implantation procedure and the selection of the appropriate device size. METHODS: An anatomical study was performed of 50 postmortem hearts, of which 15 had a history of atrial fibrillation, and of 30 consecutive patients undergoing LAA occlusion with the Amplatzer cardiac plug (ACP). The specimens were classified according to variables that can be visualized using computerized tomography (CT). The CT scans of 30 consecutive patients were classified according to the level of the LAA ostium, the left lateral ridge (LLR), the LAA limbus and distance from LAA to the mitral annulus before undergoing LAA occlusion, and the results were correlated. RESULTS: Three types of LAA orifice were defined: type I, with a usually higher, anterior LAA ostium, a short, flattened and wide LLR and almost nonexistent limbus; type II, presenting a long, pointed and narrow LLR, and a longer, more defined limbus; type III, with a lower LAA ostium, close to the left atrium floor and the mitral annulus, a marked separation from the left pulmonary vein orifices and a limbus of intermediate length. CONCLUSION: LAA with lower ostia are more difficult to occlude. Types II and III have very prominent LLRs with longer limbi, which may increase the difficulty of inserting the guide and making measurements for selection of the right ACP size.

Resultados inmediatos y a más de un año en 35 pacientes consecutivos a los que se realiza cierre de orejuela izquierda con el dispositivo Amplatzer Cardiac Plug / Immediate and one-year results in 35 consecutive patients after closure of left atrial appendage with the amplatzer cardiac plug

Introducción y objetivos. El cierre del apéndice auricular izquierdo puede ser una opción terapéutica atractiva para pacientes con fibrilación auricular no valvular y contraindicación para tomar anticoagulantes orales, siempre que se obtengan buenos resultados durante la implantación y en el seguimiento. Métodos. Se analizó a 35 pacientes consecutivos y no elegibles para los estudios aleatorizados con anticoagulantes orales a los que se implantó el dispositivo oclusor Amplatzer. Tras los primeros 5 casos, se incorporó una técnica de imagen 3D. Se analizaron los resultados de la implantación y de seguimiento durante 1 año. Resultados. La media de edad era 74,65 ± 7,61 años, con un CHADS2 de 2,41 ± 1,53 y un CHA2DS2-VASc de 3,17 ± 1,60. No se pudo implantar el dispositivo en 1 caso y en 5 fue necesario cambiar la medida seleccionada. No hubo ninguna complicación cardiaca durante la implantación ni durante la estancia hospitalaria. Hubo una complicación vascular (fístula arteriovenosa). Se realizó seguimiento con ecocardiografía transesofágica a las 24 h y tras 1, 3, 6 y 12 meses; se documentaron 5 trombos, que se resolvieron con heparina. En el seguimiento de 21,14 ± 10,09 meses, hubo 3 muertes de pacientes mayores de 80 años, ninguna de ellas cardiológica, y un accidente isquémico transitorio sin secuelas. Conclusiones. El cierre del apéndice auricular izquierdo por un operador con cierta experiencia puede ser una opción terapéutica con pocas complicaciones y con resultados a más de 1 año eficaces en la reducción de complicaciones tromboembólicas y hemorrágicas, incluso en poblaciones de muy alto riesgo (AU)

Introduction and objectives. Left atrial appendage closure can be an attractive option for patients with nonvalvular atrial fibrillation and a contraindication to oral anticoagulants, provided that satisfactory results can be achieved during implantation and follow-up. Methods. Thirty-five consecutive patients, not eligible for randomized trials with oral anticoagulants, had an Amplatzer occlusion device implanted under general anesthesia. After the first 5 patients, 3-dimensional imaging was incorporated. The results of the implantation and the follow-up were analyzed over a 1-year period. Results. The mean age was 74.65 (7.61) years, with a CHADS2 score of 2.41 (1.53) and a CHA2DS2-VASc score of 3.17 (1.60). Implantation failed in 1 patient and 5 needed a change in the selected plug size. There were no cardiac complications during the implantation or hospital stay. There was 1 vascular complication (arteriovenous fistula). Transesophageal echocardiography monitoring was performed at 24h, 1, 3, 6, and 12 months and we found 5 thrombi which were resolved with heparin. In the follow-up period of 21.14 (10.09) months, 3 patients aged>80 years died, none of them due to heart problems, and one transient ischemic stroke without further consequences. Conclusions. Left atrial appendage closure by an experienced operator can be a treatment option with few complications and with efficient results at>1 year in reducing thromboembolic and hemorrhagic complications, even in very high-risk groups (AU)