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1.
Circulation ; 149(6): 417-426, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-37970713

RESUMO

BACKGROUND: Tools for mortality prediction in patients with the severe hypercholesterolemia phenotype (low-density lipoprotein cholesterol ≥190 mg/dL) are limited and restricted to specific racial and ethnic cohorts. We sought to evaluate the predictors of long-term mortality in a large racially and ethnically diverse US patient cohort with low-density lipoprotein cholesterol ≥190 mg/dL. METHODS: We conducted a retrospective analysis of all patients with a low-density lipoprotein cholesterol ≥190 mg/dL seeking care at Montefiore from 2010 through 2020. Patients <18 years of age or with previous malignancy were excluded. The primary end point was all-cause mortality. Analyses were stratified by age, sex, and race and ethnicity. Patients were stratified by primary and secondary prevention. Cox regression analyses were used to adjust for demographic, clinical, and treatment variables. RESULTS: A total of 18 740 patients were included (37% non-Hispanic Black, 30% Hispanic, 12% non-Hispanic White, and 2% non-Hispanic Asian patients). The mean age was 53.9 years, and median follow-up was 5.2 years. Both high-density lipoprotein cholesterol and body mass index extremes were associated with higher mortality in univariate analyses. In adjusted models, higher low-density lipoprotein cholesterol and triglyceride levels were associated with an increased 9-year mortality risk (adjusted hazard ratio [HR], 1.08 [95% CI, 1.05-1.11] and 1.04 [95% CI, 1.02-1.06] per 20-mg/dL increase, respectively). Clinical factors associated with higher mortality included male sex (adjusted HR, 1.31 [95% CI, 1.08-1.58]), older age (adjusted HR, 1.19 per 5-year increase [95% CI, 1.15-1.23]), hypertension (adjusted HR, 2.01 [95% CI, 1.57-2.57]), chronic kidney disease (adjusted HR, 1.68 [95% CI, 1.36-2.09]), diabetes (adjusted HR, 1.79 [95% CI, 1.50-2.15]), heart failure (adjusted HR, 1.51 [95% CI, 1.16-1.95]), myocardial infarction (adjusted HR, 1.41 [95% CI, 1.05-1.90]), and body mass index <20 kg/m2 (adjusted HR, 3.36 [95% CI, 2.29-4.93]). A significant survival benefit was conferred by lipid-lowering therapy (adjusted HR, 0.57 [95% CI, 0.42-0.77]). In the primary prevention group, high-density lipoprotein cholesterol <40 mg/dL was independently associated with higher mortality (adjusted HR, 1.49 [95% CI, 1.06-2.09]). Temporal trend analyses showed a reduction in statin use over time (P<0.001). In the most recent time period (2019-2020), 56% of patients on primary prevention and 85% of those on secondary prevention were on statin therapy. CONCLUSIONS: In a large, diverse cohort of US patients with the severe hypercholesterolemia phenotype, we identified several patient characteristics associated with increased 9-year all-cause mortality and observed a decrease in statin use over time, in particular for primary prevention. Our results support efforts geared toward early recognition and consistent treatment for patients with severe hypercholesterolemia.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Humanos , Masculino , Pessoa de Meia-Idade , Hipercolesterolemia/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estudos Retrospectivos , LDL-Colesterol , HDL-Colesterol , Fenótipo , Fatores de Risco
2.
Artigo em Inglês | MEDLINE | ID: mdl-38841916

RESUMO

BACKGROUND: Residual transprosthetic gradient (TG) after transcatheter aortic valve replacement (TAVR) with balloon-expandable valves (BEV) may be due to suboptimal valve expansion. AIMS: To compare hemodynamics after TAVR with small BEV according to postdilation strategy. METHODS: This observational, retrospective cohort study included 184 consecutive patients from a single center treated with 23 mm Sapien 3 Ultra (Edwards Lifesciences) BEV implantation in the aortic position and enrolled between January 2020 and April 2023. Patients treated with routine postdilation (RP, n = 73) were compared to patients treated according to local standard practice (SP, n = 111). Primary endpoint was 30-day mean TG. Secondary endpoints were incidence of 30-day prosthesis-patient mismatch (PPM), technical success and device success. RESULTS: Thirty-day mean TG was lower in RP versus SP (12.3 ± 4.6 mmHg vs. 14.1 ± 5.7 mmHg, p = 0.031), and incidence of PPM was less common with RP versus SP (47.3% vs. 71.0%, p = 0.006). Technical success (98.6% vs. 99.1%, p = 0.637) and device success (93.1% vs. 90.1%, p = 0.330) did not differ between groups. Differences in 30-day mean TG were driven by patients at normal flow (12.1 ± 4.0 mmHg vs. 15.0 ± 5.5 mmHg, p = 0.014), while no differences were evident among patients at low flow (12.5 ± 5.5 mmHg vs. 11.7 ± 5.5 mmHg, p = 0.644). RP decreased height and increased width of BEV, and a linear regression established that final BEV width could predict 30-day mean TG (r = -0.6654, p < 0.0001). CONCLUSIONS: RP after TAVR with small BEV was associated with more favorable forward-flow hemodynamics than SP.

3.
Soft Matter ; 20(17): 3653-3665, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623629

RESUMO

Deformable colloids and macromolecules adsorb at interfaces as they decrease the interfacial energy between the two media. The deformability, or softness, of these particles plays a pivotal role in the properties of the interface. In this study, we employ a comprehensive in situ approach, combining neutron reflectometry with molecular dynamics simulations, to thoroughly examine the profound influence of softness on the structure of microgel Langmuir monolayers under compression. Lateral compression of both hard and soft microgel particle monolayers induces substantial structural alterations, leading to an amplified protrusion of the microgels into the aqueous phase. However, a critical distinction emerges: hard microgels are pushed away from the interface, in stark contrast to the soft ones, which remain firmly anchored to it. Concurrently, on the air-exposed side of the monolayer, lateral compression induces a flattening of the surface of the hard monolayer. This phenomenon is not observed for the soft particles as the monolayer is already extremely flat even in the absence of compression. These findings significantly advance our understanding of the key role of softness on both the equilibrium phase behavior of the monolayer and its effect when soft colloids are used as stabilizers of responsive interfaces and emulsions.

4.
Soft Matter ; 20(40): 8125-8135, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39364605

RESUMO

Soft colloids are widely used to study glass transition, aging and jamming. A high size polydispersity is typically introduced in these systems to avoid crystal formation. Here, we use binary mixtures of hollow and regular microgels with comparable sizes to inhibit crystallization. The phase behavior of the mixture is probed as a function of the number fraction of hollow microgels and characterized by small-angle X-ray scattering. Molecular dynamic simulations are used to extract the particle-particle pair potential and obtain insight on their deformation. The results suggest that the high deformability of the hollow microgels offers an alternative route to maximize the entropy without crystal formation.

5.
Chem Rev ; 122(13): 11675-11700, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35671377

RESUMO

Softness plays a key role in determining the macroscopic properties of colloidal systems, from synthetic nanogels to biological macromolecules, from viruses to star polymers. However, we are missing a way to quantify what the term "softness" means in nanoscience. Having quantitative parameters is fundamental to compare different systems and understand what the consequences of softness on the macroscopic properties are. Here, we propose different quantities that can be measured using scattering methods and microscopy experiments. On the basis of these quantities, we review the recent literature on micro- and nanogels, i.e. cross-linked polymer networks swollen in water, a widely used model system for soft colloids. Applying our criteria, we address the question what makes a nanomaterial soft? We discuss and introduce general criteria to quantify the different definitions of softness for an individual compressible colloid. This is done in terms of the energetic cost associated with the deformation and the capability of the colloid to isotropically deswell. Then, concentrated solutions of soft colloids are considered. New definitions of softness and new parameters, which depend on the particle-to-particle interactions, are introduced in terms of faceting and interpenetration. The influence of the different synthetic routes on the softness of nanogels is discussed. Concentrated solutions of nanogels are considered and we review the recent results in the literature concerning the phase behavior and flow properties of nanogels both in three and two dimensions, in the light of the different parameters we defined. The aim of this review is to look at the results on micro- and nanogels in a more quantitative way that allow us to explain the reported properties in terms of differences in colloidal softness. Furthermore, this review can give researchers dealing with soft colloids quantitative methods to define unambiguously which softness matters in their compound.


Assuntos
Nanogéis/química , Polietilenoglicóis/química , Polietilenoimina , Coloides , Polietilenoimina/química , Polímeros/química
6.
Macromol Rapid Commun ; 45(13): e2400043, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38613338

RESUMO

The compressibility of soft colloids influences their phase behavior and flow properties, especially in concentrated suspensions. Particle compressibility, which is proportional to the reciprocal of the bulk modulus K, is a key parameter for soft polymer-based particles that can be compressed in crowded environments. Here, microgels with different degrees of cross-linking, i.e., softness, are investigated below and above their volume phase transition temperature (VPTT). By combining molecular dynamics simulations with small-angle neutron scattering with contrast variation, a change in the particle bulk moduli of two orders of magnitude is observed. The degree of cross-linking has a significant impact on the bulk modulus of the swollen microgel, while above the VPTT the values of K are almost independent of the cross-linking density. The excellent agreement between experimental results and simulations also highlight that the model microgels from computer simulations possess both the internal architecture and the elastic properties of real polymeric networks. This paves the way to a systematic use of simulations to investigate the behavior of dense microgel suspensions below and above their VPTT.


Assuntos
Microgéis , Simulação de Dinâmica Molecular , Transição de Fase , Microgéis/química , Polímeros/química , Espalhamento a Baixo Ângulo , Géis/química
7.
Eur Heart J ; 44(15): 1331-1339, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36883599

RESUMO

AIMS: Paravalvular regurgitation (PVR) after transcatheter aortic valve implantation (TAVI) is associated with increased morbidity and mortality. The effect of transcatheter interventions to treat PVR after the index TAVI was investigated. METHODS AND RESULTS: A registry of consecutive patients who underwent transcatheter intervention for ≥ moderate PVR after the index TAVI at 22 centers. The principal outcomes were residual aortic regurgitation (AR) and mortality at 1 year after PVR treatment. A total of 201 patients were identified: 87 (43%) underwent redo-TAVI, 79 (39%) plug closure, and 35 (18%) balloon valvuloplasty. Median TAVI-to-re-intervention time was 207 (35; 765) days. The failed valve was self-expanding in 129 (63.9%) patients. The most frequent devices utilized were a Sapien 3 valve for redo-TAVI (55, 64%), an AVP II as plug (33, 42%), and a True balloon for valvuloplasty (20, 56%). At 30 days, AR ≥ moderate persisted in 33 (17.4%) patients: 8 (9.9%) after redo-TAVI, 18 (25.9%) after plug, and 7 (21.9%) after valvuloplasty (P = 0.036). Overall mortality was 10 (5.0%) at 30 days and 29 (14.4%) at 1 year: 0, 8 (10.1%), and 2 (5.7%) at 30 days (P = 0.010) and 11 (12.6%), 14 (17.7%), and 4 (11.4%) at 1 year (P = 0.418), after redo-TAVI, plug, and valvuloplasty, respectively. Regardless of treatment strategy, patients in whom AR was reduced to ≤ mild had lower mortality at 1 year compared with those with AR persisting ≥ moderate [11 (8.0%) vs. 6 (21.4%); P = 0.007]. CONCLUSION: This study describes the efficacy of transcatheter treatments for PVR after TAVI. Patients in whom PVR was successfully reduced had better prognosis. The selection of patients and the optimal PVR treatment modality require further investigation.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Prognóstico , Resultado do Tratamento , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia
8.
Eur Heart J ; 44(10): 822-832, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36445158

RESUMO

AIMS: The impact of sexuality in patients with significant tricuspid regurgitation (TR) undergoing transcatheter tricuspid valve intervention (TTVI) is unknown. The aim of this study was to investigate sex-specific outcomes in patients with significant TR treated with TTVI vs. medical therapy alone. METHODS AND RESULTS: The Transcatheter Tricuspid Valve Therapies (TriValve) registry collected data on patients with significant TR from 24 centres who underwent TTVI from 2016 to 2021. A control cohort was formed by medically managed patients with ≥severe isolated TR diagnosed in 2015-18. The primary endpoint was freedom from all-cause mortality. Secondary endpoints were heart failure (HF) hospitalization, New York Heart Association (NYHA) functional status, and TR severity. One-year outcomes were assessed for the TriValve cohort and compared with the control cohort with the inverse probability of treatment weighting (IPTW). A total of 556 and 2072 patients were included from the TriValve and control groups, respectively. After TTVI, there was no difference between women and men in 1-year freedom from all-cause mortality 80.9% vs. 77.9%, P = 0.56, nor in HF hospitalization (P = 0.36), NYHA Functional Classes III and IV (P = 0.17), and TR severity >2+ at last follow-up (P = 0.42). Multivariable Cox-regression weighted by IPTW showed improved 1-year survival after TTVI compared with medical therapy alone in both women (adjusted hazard ratio 0.45, 95% confidence interval 0.23-0.83, P = 0.01) and men (adjusted hazard ratio 0.42, 95% confidence interval 0.18-0.89, P = 0.03). CONCLUSION: After TTVI in high-risk patients, there were no sex-related differences in terms of survival, HF hospitalization, functional status, and TR reduction up to 1 year. The IPTW analysis shows a survival benefit of TTVI over medical therapy alone in both women and men.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Masculino , Humanos , Feminino , Valva Tricúspide/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Resultado do Tratamento , Sistema de Registros , Insuficiência Cardíaca/complicações
9.
Phys Rev Lett ; 131(25): 258202, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38181345

RESUMO

In situ interfacial rheology and numerical simulations are used to investigate microgel monolayers in a wide range of packing fractions, ζ_{2D}. The heterogeneous particle compressibility determines two flow regimes characterized by distinct master curves. To mimic the microgel architecture and reproduce experiments, an interaction potential combining a soft shoulder with the Hertzian model is introduced. In contrast to bulk conditions, the elastic moduli vary nonmonotonically with ζ_{2D} at the interface, confirming long-sought predictions of reentrant behavior for Hertzian-like systems.

10.
Langmuir ; 39(22): 7530-7538, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37220302

RESUMO

The softness of microgels depends on many aspects, such as particle characteristic lengths, sample concentration, chemical composition of the sample, and elastic moduli of the particle. Here, the response to crowding of ionic microgels is studied. Charged and uncharged ionic microgels are studied in concentrated suspensions of both neutral and ionic microgels with the same swollen size. The combination of small-angle X-ray and neutron scattering with contrast variation allows us to probe both the particle-to-particle arrangement and the response of individual ionic microgels to crowding. When the ionic microgels are uncharged, initial isotropic deswelling followed by faceting is observed. Therefore, the ionizable groups in the polymeric network do not affect the response of the ionic microgel to crowding, which is similar to what has been reported for neutral microgels. In contrast, the kind of microgels composing the matrix plays a key role once the ionic microgels are charged. If the matrix is composed of neutral microgels, a pronounced faceting and negligible deswelling is observed. When only charged ionic microgels are present in the suspension, isotropic deswelling without faceting is dominant.

11.
Phys Chem Chem Phys ; 25(4): 2810-2820, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36052753

RESUMO

Micro- and nanogels are widely used to stabilise emulsions and simultaneously implement their responsiveness to the external stimuli. One of the factors that improves the emulsion stability is the nanogel softness. Here, we study how the softest nanogels that can be synthesised with precipitation polymerisation of N-isopropylacrylamide (NIPAM), the ultra-low crosslinked (ULC) nanogels, stabilise oil-in-water emulsions. We show that ULC nanogels can efficiently stabilise emulsions already at low mass concentrations. These emulsions are resistant to droplet flocculation, stable against coalescence, and can be easily broken upon an increase in temperature. The resistance to flocculation of the ULC-stabilised emulsion droplets is similar to the one of emulsions stabilised by linear pNIPAM. In contrast, the stability against coalescence and the temperature-responsiveness closely resemble those of emulsions stabilised by regularly crosslinked pNIPAM nanogels. The reason for this combination of properties is that ULC nanogels can be thought of as colloids in between flexible macromolecules and particles. As a polymer, ULC nanogels can efficiently stretch at the interface and cover it uniformly. As a regularly crosslinked nanogel particle, ULC nanogels protect emulsion droplets against coalescence by providing a steric barrier and rapidly respond to changes in external stimuli thus breaking the emulsion. This polymer-particle duality of ULC nanogels can be exploited to improve the properties of emulsions for various applications, for example in heterogeneous catalysis or in food science.

12.
Nano Lett ; 22(6): 2412-2418, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35258981

RESUMO

Particle size disparities suppress crystallization. However, soft deformable nanogels can change the size of the larger particles in suspension and crystallize even at a high initial size-polydispersity. Using neutron scattering with contrast variation, the response of individual nanogels in crowded environments was probed, and an increase of the parameter describing size-polydispersity was found, which is often interpreted as deformation. Here, computer simulations are used to generate deformed nanogels and the corresponding form factor. The data are fitted with the spherical model used to analyze scattering data. The fits show the same qualitative increase of the parameter related to the size-polydispersity with increasing particle deformation. Starting from the simulated deformed spheres, we also reproduce experimental scattering data. A further analysis of the particle shows that the size disparities between nanogels do not increase significantly. In contrast, their shapes strongly vary from one nanogel to the other.


Assuntos
Nanogéis , Cristalização , Tamanho da Partícula
13.
Heart Fail Clin ; 19(4): 491-504, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37714589

RESUMO

Current guidelines of aortic stenosis (AS) management focus on valve parameters, LV systolic dysfunction, and symptoms; however, emerging data suggest that there may be benefit of aortic valve replacement before it becomes severe by present criteria. Myocardial assessment using novel multimodality imaging techniques exhibits subclinical myocardial injury and remodeling at various stages before guideline-directed interventions, which predicts adverse outcomes. This raises the question of whether implementing serial myocardial assessment should become part of the standard appraisal, thereby identifying high-risk patients aiming to minimize adverse outcomes.


Assuntos
Estenose da Valva Aórtica , Imagem Multimodal , Humanos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Miocárdio
14.
Heart Fail Rev ; 27(4): 1193-1200, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34291400

RESUMO

A severe secondary mitral regurgitation (SMR) can be found in a significant portion of patients affected by advanced heart failure (AHF). Conventional therapies (optimal medical therapy, devices, surgery) present restricted clinical efficacy in this stage of the left ventricle disease which is burdened by high mortality and morbidity rates. Although the treatment of choice is represented by heart transplantation (HTx), there is an unmet need related to the limited supply of donor hearts (as opposed to the growing prevalence of AHF) and the low eligibility of highly symptomatic patients. In case of concomitant severe SMR, transcatheter mitral valve therapies (repair and replacement) may play a crucial role in this setting. While a direct prognostic improvement after correction of SMR has yet to be proved, AHF patients can benefit from the following: hemodynamic stabilization, symptomatic relief, normalization of pulmonary arterial pressures, and reduction in hospitalizations for acute heart failure. Obtaining these results may lead to the clinical consequences of reaching the HTx in good enough clinical status (bridge to heart transplantation), becoming eligible for the HTx (bridge to HTx candidacy), and being delisted for clinical improvement (bridge to recovery). Therefore, achieving traditional secondary endpoints in patients with AHF and SMR can translate into significant clinical implications.


Assuntos
Insuficiência Cardíaca , Transplante de Coração , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Cateterismo Cardíaco/métodos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Doadores de Tecidos , Resultado do Tratamento
15.
Rev Cardiovasc Med ; 23(5): 163, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-39077595

RESUMO

Background and Objective: As one of the most prevalent valvular pathologies affecting millions globally, moderate-to-severe tricuspid regurgitation (TR) predisposes to increased mortality. Despite the well-established risk of adverse outcomes, an overwhelming majority of TR patients are managed conservatively due to challenges associated with timely diagnosis, clinical course of the disease, competing comorbities that carry prohibitive surgical risk, and poor surgical outcomes. These challenges highlight the importance of transcatheter tricuspid valve replacement (TTVR) which has restructured TR management in promising and innovative ways. Methods: We start with an overview of the pathophysiology of TR considering its implications in management. We then elaborate on the current state of TR management, including its limitations, thereby highlighting the unique role of TTVR. This is followed by a review of perioperative considerations such as careful patient selection, role of multimodality imaging, the various imaging techniques that are available and their contribution towards successful TTVR. We then review the valves that are currently available and under investigation, including the latest data available on device efficacy and safety, and highlight the ongoing clinical trials. Results and Conclusions: TTVR is evolving at an exponential pace and has made its mark in the treatment of severe symptomatic tricuspid regurgitation. The promising results sustained by currently available devices and ongoing investigation of valves under development continue to pave the path for further innovation in transcatheter interventions. However, it is important to acknowledge and appreciate the novelty of this approach, the lack of long-term data on safety, efficacy, morbidity, and mortality, and use the lessons learned from real-world experiences to provide a definitive and reproducible solution for patients with symptomatic TR.

16.
Catheter Cardiovasc Interv ; 100(4): 620-627, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35842775

RESUMO

OBJECTIVES: To assess feasibility and safety of second-generation left atrial appendage closure (LAAC) Ultraseal device in patients with nonvalvular atrial fibrillation (NVAF). BACKGROUND: LAAC with first-generation Ultraseal device (Cardia, Eagan, Minnesota) has been shown to be a feasible therapeutic option in patients with NVAF. However, there is a paucity of data regarding the novel second-generation Ultraseal device. METHODS: All patients with NVAF undergoing second-generation Ultraseal device implantation between February 2018 and September 2020 were included in a multicenter international registry. Periprocedural and post-discharge events were collected through 6-month follow-up. Co-primary efficacy endpoints were device success and technical success while primary safety endpoint was in-hospital major adverse event (MAE) occurrence. RESULTS: A total of 52 patients were included: mean age 75 ± 8, 30.8% women, mean HAS-BLED 3 ± 1. The device was successfully implanted in all patients. Technical success was achieved in 50 patients (96.1%). In-hospital MAEs occurred in three patients (5.8%). The incidence of 6-month all-cause death and major bleeding was 11.6% and 2.1%, respectively. No strokes, transient ischemic attacks, systemic embolisms, or device embolization were reported after discharge. CONCLUSIONS: Second-generation Ultraseal device implantation was associated with high success rates and a low incidence of peri-procedural complications. Larger studies with longer follow-up are warranted to further evaluate the safety and the efficacy of this device, especially at long-term follow-up.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Assistência ao Convalescente , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Feminino , Humanos , Masculino , Alta do Paciente , Sistema de Registros , Resultado do Tratamento
17.
Soft Matter ; 18(31): 5750-5758, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35899831

RESUMO

The softness of an object can be quantified by one of the fundamental elastic moduli. The bulk modulus of the particle is most appropriate in the presence of isotropic compressions. Here, we use small-angle neutron scattering with contrast variation to directly access the bulk modulus of polymeric nanocapsules - pNIPAM-based hollow nanogels. We show that the size of the cavity is the most important quantity that determines the softness of hollow nanogels. During initial compression, the polymer collapses into the cavity and leads to a large change in the particle volume, resulting in a very small initial bulk modulus. Once the cavity is partially occupied by the polymer, the hollow nanogels become significantly stiffer since now the highly crosslinked network has to be compressed. Furthermore, we show that the larger the cavity, the softer the nanogel.

18.
J Chem Phys ; 157(19): 194901, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414436

RESUMO

The response of soft colloids to crowding depends sensitively on the particles' compressibility. Nanogel suspensions provide model systems that are often studied to better understand the properties of soft materials and complex fluids from the formation of colloidal crystals to the flow of viruses, blood, or platelet cells in the body. Large spherical nanogels, when embedded in a matrix of smaller nanogels, have the unique ability to spontaneously deswell to match their size to that of the nanogel composing the matrix. In contrast to hard colloids, this self-healing mechanism allows for crystal formation without giving rise to point defects or dislocations. Here, we show that anisotropic ellipsoidal nanogels adapt both their size and their shape depending on the nature of the particles composing the matrix in which they are embedded. Using small-angle neutron scattering with contrast variation, we show that ellipsoidal nanogels become spherical when embedded in a matrix of spherical nanogels. In contrast, the anisotropy of the ellipsoid is enhanced when they are embedded in a matrix of anisotropic nanogels. Our experimental data are supported by Monte Carlo simulations that reproduce the trend of decreasing aspect ratio of ellipsoidal nanogels with increasing crowding by a matrix of spherical nanogels.


Assuntos
Coloides , Polietilenoglicóis , Nanogéis , Anisotropia , Polietilenoglicóis/química , Coloides/química
19.
Catheter Cardiovasc Interv ; 97(4): E536-E543, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32584507

RESUMO

BACKGROUND: Stroke is a feared complication of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR). OBJECTIVES: With this meta-analysis we aimed to evaluate the incidence of 30-day stroke with TAVR and SAVR focusing on its possible correlation with surgical risk. METHODS: Major electronic databases were searched for studies published between January 2002 and October 2019 reporting the rates of 30-day stroke after TAVR and SAVR. Data were pooled using fixed- and random-effects models. The primary outcome of the study was stroke rate within 30-day from TAVR or SAVR. Results were stratified according to surgical risk score (high, intermediate and low). RESULTS: A total of 23 studies were identified (TAVR: 14,589 patients; SAVR: 11,681 patients). Regardless of the model used, in the overall population TAVR was associated with a significant reduction in the risk of stroke compared with SAVR (fixed effect: OR 0.78, 95% CI 0.66-0.92, p = .003; random-effects: OR 0.80, 95% CI 0.64-1.00, p = .045). Rates of 30-day stroke after TAVR and SAVR were not significantly different in the high- (OR 1.01, 95% CI 0.44-1.98, p = .105) and intermediate-risk groups (OR 0.92, 95% CI 0.63-1.36, p = .319), while low-risk patients had a lower rate of 30-day stroke after TAVR than SAVR (OR 0.65, 95% CI 0.50-0.83, p < .001). Meta-regression showed a significant association between surgical risk score and 30-day stroke rate (p = .007). CONCLUSIONS: TAVR is associated with a lower risk of 30-day stroke compared with SAVR, mainly as a result of the significant advantage observed in patients at low surgical risk.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
20.
Catheter Cardiovasc Interv ; 97(6): E789-E800, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33332744

RESUMO

BACKGROUND: The role of the target vessel in percutaneous revascularization of chronic total occlusion (CTO) is unclear. OBJECTIVE: We sought to assess the long-term results of percutaneous coronary intervention (PCI) for CTO lesions in each coronary artery and to investigate the impact of successful revascularization and previous myocardial infarction (MI) in the territory of the target vessel. METHODS AND RESULTS: Cohort observational study on 1,124 patients who have undergone CTO PCI attempt: 371 on left anterior descending artery (LAD), 485 right coronary artery, and 268 left circumflex. Patients were further stratified by successfully revascularized and not-revascularized CTO (CTO-NR). Vessels affected by a previous MI were defined as infarct-related artery (IRA). The primary endpoint was cardiac death; the secondary endpoint was the combined rate of sudden cardiac-death and sustained ventricular-arrhythmias (SCD/SVAs). Propensity score-matching was performed to evaluate LAD versus NON-LAD CTO. Up to 12-year follow-up, the clinical benefit associated with successful PCI was consistent across the three groups. CTO-NR had the greatest association with cardiac death and SCD/SVAs in each coronary artery and in IRA-CTO patients. CONCLUSIONS: Unsuccessful percutaneous CTO revascularization was associated with lower cardiac survival and freedom from SCD/SVAs, irrespective of the vessel treated. This result was mainly driven by patients with an IRA CTO.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/cirurgia , Morte Súbita Cardíaca/etiologia , Seguimentos , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Resultado do Tratamento
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