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1.
ACS Nano ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990155

RESUMO

Photocatalysis with plasmonic nanostructures has lately emerged as a transformative paradigm to drive and alter chemical reactions using light. At the surface of metallic nanoparticles, photoexcitation results in strong near fields, short-lived high-energy "hot" carriers, and light-induced heating, thus creating a local environment where reactions can occur with enhanced efficiencies. In this context, it is critical to understand how to manipulate the nonequilibrium processes triggered by light, as their ultrafast (femto- to picoseconds) relaxation dynamics compete with the process of energy transfer toward the reactants. Accurate predictions of the plasmon photocatalytic activity can lead to optimized nanophotonic architectures with enhanced selectivity and rates, operating beyond the intrinsic limitations of the steady state. Here, we report on an original modeling approach to quantify, with space, time, and energy resolution, the ultrafast energy exchange from plasmonic hot carriers (HCs) to molecular systems adsorbed on the metal nanoparticle surface while consistently accounting for photothermal bond activation. Our analysis, illustrated for a few typical cases, reveals that the most energetic nonequilibrium carriers (i.e., with energies well far from the Fermi level) may introduce a wavelength-dependence of the reaction rates, and it elucidates on the role of the carriers closer to the Fermi energy and the photothermally heated lattice, suggesting ways to enhance and optimize each contribution. We show that the overall reaction rates can benefit strongly from using pulsed illumination with the optimal pulse width determined by the properties of the system. Taken together, these results contribute to the rational design of nanoreactors for pulsed catalysis, which calls for predictive modeling of the ultrafast HC-hot adsorbate energy transfer.

2.
J Cardiovasc Magn Reson ; 26(2): 101050, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909657

RESUMO

BACKGROUND: Disordered lymphatic drainage is common in congenital heart diseases (CHD), but thoracic duct (TD) drainage patterns in heterotaxy have not been described in detail. This study sought to describe terminal TD sidedness in heterotaxy and its associations with other anatomic variables. METHODS: This was a retrospective, single-center study of patients with heterotaxy who underwent cardiovascular magnetic resonance imaging at a single center between July 1, 2019 and May 15, 2023. Patients with (1) asplenia (right isomerism), (2) polysplenia (left isomerism) and (3) pulmonary/abdominal situs inversus (PASI) plus CHD were included. Terminal TD sidedness was described as left-sided, right-sided, or bilateral. RESULTS: Of 115 eligible patients, the terminal TD was visualized in 56 (49 %). The terminal TD was left-sided in 25 patients, right-sided in 29, and bilateral in two. On univariate analysis, terminal TD sidedness was associated with atrial situs (p = 0.006), abdominal situs (p = 0.042), type of heterotaxy (p = 0.036), the presence of pulmonary obstruction (p = 0.041), superior vena cava sidedness (p = 0.005), and arch sidedness (p < 0.001). On multivariable analysis, only superior vena cava and aortic arch sidedness were independently associated with terminal TD sidedness. CONCLUSIONS: Terminal TD sidedness is highly variable in patients with heterotaxy. Superior vena cava and arch sidedness are independently associated with terminal TD sidedness. Type of heterotaxy was not independently associated with terminal TD sidedness. This data improves the understanding of anatomic variation in patients with heterotaxy and may be useful for planning for lymphatic interventions.

3.
Arch. cardiol. Méx ; 94(2): 219-239, Apr.-Jun. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1556919

RESUMO

resumen está disponible en el texto completo


Abstract This consensus of nomenclature and classification for congenital bicuspid aortic valve and its aortopathy is evidence-based and intended for universal use by physicians (both pediatricians and adults), echocardiographers, advanced cardiovascular imaging specialists, interventional cardiologists, cardiovascular surgeons, pathologists, geneticists, and researchers spanning these areas of clinical and basic research. In addition, as long as new key and reference research is available, this international consensus may be subject to change based on evidence-based data1.

4.
Pathol Int ; 74(7): 379-386, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38712791

RESUMO

This paper illustrates a valve-sparing cardiac dissection technique that keeps the atrioventricular and semilunar valves and other important cardiac structures intact. The technique minimizes disruption in heart specimens, so they remain suitable for teaching, demonstration, and further research. When performed following the perfusion-distension method of fixation, as our group previously described, this technique could optimize the preservation of heart specimens for teaching and digital archiving postdissection.


Assuntos
Dissecação , Valvas Cardíacas , Humanos , Dissecação/métodos , Valvas Cardíacas/patologia , Valvas Cardíacas/cirurgia , Criança , Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
5.
Pediatr Transplant ; 28(4): e14742, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38702926

RESUMO

BACKGROUND: As more pediatric patients become candidates for heart transplantation (HT), understanding pathological predictors of outcome and the accuracy of the pretransplantation evaluation are important to optimize utilization of scarce donor organs and improve outcomes. The authors aimed to investigate explanted heart specimens to identify pathologic predictors that may affect cardiac allograft survival after HT. METHODS: Explanted pediatric hearts obtained over an 11-year period were analyzed to understand the patient demographics, indications for transplant, and the clinical-pathological factors. RESULTS: In this study, 149 explanted hearts, 46% congenital heart defects (CHD), were studied. CHD patients were younger and mean pulmonary artery pressure and resistance were significantly lower than in cardiomyopathy patients. Twenty-one died or underwent retransplantation (14.1%). Survival was significantly higher in the cardiomyopathy group at all follow-up intervals. There were more deaths and the 1-, 5- and 7-year survival was lower in patients ≤10 years of age at HT. Early rejection was significantly higher in CHD patients exposed to homograft tissue, but not late rejection. Mortality/retransplantation rate was significantly higher and allograft survival lower in CHD hearts with excessive fibrosis of one or both ventricles. Anatomic diagnosis at pathologic examination differed from the clinical diagnosis in eight cases. CONCLUSIONS: Survival was better for the cardiomyopathy group and patients >10 years at HT. Prior homograft use was associated with a higher prevalence of early rejection. Ventricular fibrosis (of explant) was a strong predictor of outcome in the CHD group. We presented several pathologic findings in explanted pediatric hearts.


Assuntos
Rejeição de Enxerto , Sobrevivência de Enxerto , Cardiopatias Congênitas , Transplante de Coração , Humanos , Criança , Masculino , Feminino , Pré-Escolar , Lactente , Adolescente , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/patologia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Seguimentos , Cardiomiopatias/cirurgia , Cardiomiopatias/patologia , Reoperação , Recém-Nascido , Análise de Sobrevida
6.
Pediatr Dev Pathol ; : 10935266241250235, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38762771

RESUMO

Ebstein anomaly (EA) is a rare congenital heart defect characterized by abnormal development of the tricuspid valve (TV) and right ventricular myocardium. This study documents 2 dramatic cases of fetal EA characterized by hydrops and cardiomegaly, leading to intrauterine or early neonatal death. These clinical outcomes were associated with morphological abnormalities including severe tricuspid regurgitation, unguarded TV orifice, pulmonary atresia, and flattened right ventricular myocardium. This study highlights that these adverse anatomical features may result in unfavorable clinical outcomes in fetal EA. While timely identification of such features by prenatal ultrasound is crucial for providing accurate prognostic stratification and guiding treatment decisions, fetopsy may be necessary to discern EA among the spectrum of right-heart anomalies.

7.
Arch Cardiol Mex ; 94(2): 219-239, 2024 02 07.
Artigo em Espanhol | MEDLINE | ID: mdl-38325117

RESUMO

This consensus of nomenclature and classification for congenital bicuspid aortic valve and its aortopathy is evidence-based and intended for universal use by physicians (both pediatricians and adults), echocardiographers, advanced cardiovascular imaging specialists, interventional cardiologists, cardiovascular surgeons, pathologists, geneticists, and researchers spanning these areas of clinical and basic research. In addition, as long as new key and reference research is available, this international consensus may be subject to change based on evidence-based data1.


Este consenso de nomenclatura y clasificación para la válvula aórtica bicúspide congénita y su aortopatía está basado en la evidencia y destinado a ser utilizado universalmente por médicos (tanto pediatras como de adultos), médicos ecocardiografistas, especialistas en imágenes avanzadas cardiovasculares, cardiólogos intervencionistas, cirujanos cardiovasculares, patólogos, genetistas e investigadores que abarcan estas áreas de investigación clínica y básica. Siempre y cuando se disponga de nueva investigación clave y de referencia, este consenso internacional puede estar sujeto a cambios de acuerdo con datos basados en la evidencia1.

8.
J Educ Teach Emerg Med ; 9(1): C1-C15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38344053

RESUMO

Audience and Type of Curriculum: This longitudinal leadership curriculum is designed for emergency medicine residents at all levels, with individual sessions designed for each residency year. Length of Curriculum: This curriculum runs once annually over three to four years of emergency medicine residency. Introduction: Leadership is a vital skill for emergency physicians but is often passively taught during residency training. Strong leadership skills can lead to improved patient outcomes, but very few residency programs in any specialty and no emergency medicine residency programs have published comprehensive leadership training curricula. Educational Goals: The goals of this curriculum are to expose Emergency Medicine residents to the basics of leadership, to provide a graduated series of interactive, psychologically safe environments to explore individual leadership styles, to review interesting relevant literature, and to discuss leadership principles and experiences with senior leaders in our Emergency Department. Educational Methods: The educational strategies used in this curriculum include: brief lecture-style seminars, small group discussion and reflection, and a panel-style discussion. Research Methods: The educational content of this curriculum was evaluated by learners via feedback surveys after each session. Results: Course evaluations conducted in both 2017 and 2020 showed that more than 89% of resident participants found these sessions "useful" or "very useful." All residents surveyed agreed that leadership is an important topic for emergency medicine residency, and 76% felt that the inclusion of leadership content strengthened the residency's curriculum. Suggestions for future topics included handling personal conflict and discussing transitions in leadership during yearly residency promotions. Discussion: The curriculum has been successfully implemented for seven years. It has proven to be sustainable and requires minimal resources. The residents report high satisfaction with the curriculum and agree that formal instruction on the topic of leadership is important to their on-shift performance and careers. Topics: Leadership, communication.

9.
JMIR Hum Factors ; 11: e49331, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206662

RESUMO

BACKGROUND: Falls are common in people with multiple sclerosis (MS), causing injuries, fear of falling, and loss of independence. Although targeted interventions (physical therapy) can help, patients underreport and clinicians undertreat this issue. Patient-generated data, combined with clinical data, can support the prediction of falls and lead to timely intervention (including referral to specialized physical therapy). To be actionable, such data must be efficiently delivered to clinicians, with care customized to the patient's specific context. OBJECTIVE: This study aims to describe the iterative process of the design and development of Multiple Sclerosis Falls InsightTrack (MS-FIT), identifying the clinical and technological features of this closed-loop app designed to support streamlined falls reporting, timely falls evaluation, and comprehensive and sustained falls prevention efforts. METHODS: Stakeholders were engaged in a double diamond process of human-centered design to ensure that technological features aligned with users' needs. Patient and clinician interviews were designed to elicit insight around ability blockers and boosters using the capability, opportunity, motivation, and behavior (COM-B) framework to facilitate subsequent mapping to the Behavior Change Wheel. To support generalizability, patients and experts from other clinical conditions associated with falls (geriatrics, orthopedics, and Parkinson disease) were also engaged. Designs were iterated based on each round of feedback, and final mock-ups were tested during routine clinical visits. RESULTS: A sample of 30 patients and 14 clinicians provided at least 1 round of feedback. To support falls reporting, patients favored a simple biweekly survey built using REDCap (Research Electronic Data Capture; Vanderbilt University) to support bring-your-own-device accessibility-with optional additional context (the severity and location of falls). To support the evaluation and prevention of falls, clinicians favored a clinical dashboard featuring several key visualization widgets: a longitudinal falls display coded by the time of data capture, severity, and context; a comprehensive, multidisciplinary, and evidence-based checklist of actions intended to evaluate and prevent falls; and MS resources local to a patient's community. In-basket messaging alerts clinicians of severe falls. The tool scored highly for usability, likability, usefulness, and perceived effectiveness (based on the Health IT Usability Evaluation Model scoring). CONCLUSIONS: To our knowledge, this is the first falls app designed using human-centered design to prioritize behavior change and, while being accessible at home for patients, to deliver actionable data to clinicians at the point of care. MS-FIT streamlines data delivery to clinicians via an electronic health record-embedded window, aligning with the 5 rights approach. Leveraging MS-FIT for data processing and algorithms minimizes clinician load while boosting care quality. Our innovation seamlessly integrates real-world patient-generated data as well as clinical and community-level factors, empowering self-care and addressing the impact of falls in people with MS. Preliminary findings indicate wider relevance, extending to other neurological conditions associated with falls and their consequences.


Assuntos
Acidentes por Quedas , Geriatria , Aplicativos Móveis , Esclerose Múltipla , Humanos , Acidentes por Quedas/prevenção & controle , Medo , Esclerose Múltipla/terapia
10.
J Am Coll Cardiol ; 83(4): 516-527, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37939977

RESUMO

BACKGROUND: Neo-aortic root dilatation can lead to significant late morbidity after the arterial switch operation (ASO) for dextro-transposition of the great arteries (d-TGA). OBJECTIVES: We sought to examine the growth of the neo-aortic root in d-TGA. METHODS: A single-center, retrospective cohort study of patients who underwent the ASO between July 1, 1981 and September 30, 2022 was performed. Morphology was categorized as dextro-transposition of the great arteries with intact ventricular septum (d-TGA-IVS), dextro-transposition of the great arteries with ventricular septal defect (d-TGA-VSD), and double-outlet right ventricle-transposition of the great arteries type (DORV-TGA). Echocardiographically determined diameters and derived z scores were measured at the annulus, sinus of Valsalva, and sinotubular junction immediately before the ASO and throughout follow-up. Trends in root dimensions over time were assessed using linear mixed-effects models. The association between intrinsic morphology and the composite of moderate-severe aortic regurgitation (AR) and neo-aortic valve or root intervention was evaluated with univariable and multivariable Cox proportional hazards models. RESULTS: Of 1,359 patients who underwent the ASO, 593 (44%), 666 (49%), and 100 (7%) patients had d-TGA-IVS, d-TGA-VSD, and DORV-TGA, respectively. Each patient underwent a median of 5 echocardiograms (Q1-Q3: 3-10 echocardiograms) over a median follow-up of 8.6 years (range: 0.1-39.3 years). At 30 years, patients with DORV-TGA demonstrated greater annular (P < 0.001), sinus of Valsalva (P = 0.039), and sinotubular junction (P = 0.041) dilatation relative to patients with d-TGA-IVS. On multivariable analysis, intrinsic anatomy, older age at ASO, at least mild AR at baseline, and high-risk root dilatation were associated with moderate-severe AR and neo-aortic valve or root intervention at late follow-up (all P < 0.05). CONCLUSIONS: Longitudinal surveillance of the neo-aortic root is warranted long after the ASO.


Assuntos
Insuficiência da Valva Aórtica , Comunicação Interventricular , Transposição dos Grandes Vasos , Humanos , Lactente , Transposição dos Grandes Vasos/diagnóstico por imagem , Transposição dos Grandes Vasos/cirurgia , Estudos Retrospectivos , Aorta Torácica , Seguimentos , Prognóstico , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/epidemiologia , Dilatação Patológica , Resultado do Tratamento
12.
JTCVS Open ; 15: 412-423, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37808028

RESUMO

Objective: This study aimed to describe the histomorphologic characteristics of resected (unroofed) common wall tissue from repair of anomalous aortic origin of a coronary artery and to determine whether the histologic features correlate with clinical and imaging findings. Methods: The histology of resected tissue was analyzed and reviewed for the presence of fibrointimal hyperplasia, smooth muscle disarray, mucoid extracellular matrix accumulation, mural fibrosis, and elastic fiber disorganization and fragmentation using hematoxylin and eosin and special stains. Clinical, computed tomography imaging, and surgical data were correlated with the histopathologic findings. Results: Twenty specimens from 20 patients (age range, 7-18 years; 14 males) were analyzed. Anomalous aortic origin of a coronary artery involved the right coronary in 16 (80%), and a slit-like ostium was noted in 18 (90%). By computed tomography imaging, the median proximal coronary artery eccentricity index was 0.4 (range, 0.20-0.90). The median length of intramural course was 8.2 mm (range, 2.6-15.2 mm). The anomalous vessel was determined to be interarterial in 14 patients (93%, 15 had evaluable images). The median distance from a commissure was 2.5 mm above the sinotubular junction (STJ) (range: 2 mm below the STJ-14 mm above the STJ). Prominent histopathologic findings included elastic fiber alterations, mural fibrosis, and smooth muscle disarray. The shared wall of the aorta and intramural coronary artery is more similar to the aorta histologically. Mural fibrosis and elastic fiber abnormalities tended to be more severe in patients >10 years of age at the time of surgery, but this did not reach statistical significance. The extent of vascular changes did not appear to have a clear relationship with the imaging features. Conclusions: The findings confirm the aortic wall-like quality of the intramural segment of the coronary artery and the presence of pathologic alterations in the wall microstructure.

13.
J Am Coll Cardiol ; 82(11): 1108-1120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37673512

RESUMO

Patients with congenital heart disease associated with a higher risk for ventricular arrhythmias (VA) and sudden cardiac death (SCD) can be divided conceptually into those with discrete mechanisms for reentrant monomorphic ventricular tachycardia (VT) (Group A) and those with more diffuse substrates (Group B). Part I of this review addresses Group A lesions, which predominantly consist of tetralogy of Fallot and related variants. Well-defined anatomic isthmuses for reentrant monomorphic VT are interposed between surgical scars and the pulmonary or tricuspid annulus. The most commonly implicated critical isthmus for VT is the conal septum that divides subpulmonary from subaortic outlets. Programmed ventricular stimulation can be helpful in risk stratification. Although catheter ablation is not generally considered an alternative to the implantable cardioverter-defibrillator (ICD) for prevention of SCD, emerging data suggest that there is a subset of carefully selected patients who may not require ICDs after successful monomorphic VT ablation.


Assuntos
Ablação por Cateter , Desfibriladores Implantáveis , Cardiopatias Congênitas , Humanos , Adulto , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/terapia
14.
J Am Coll Cardiol ; 82(11): 1121-1130, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37673513

RESUMO

There are marked variations in the incidence of sudden cardiac death (SCD) and in the substrates for ventricular arrhythmias (VAs) across the gamut of congenital heart defects. In this 2-part review, patients with higher-risk forms of congenital heart disease (CHD) were conceptually categorized into those with discrete anatomic isthmuses for macro-reentrant ventricular tachycardia (VT) (Group A) and those with more diffuse or less well-defined substrates (Group B) that include patchy or extensive myocardial fibrosis. The latter category encompasses CHD lesions such as Ebstein anomaly, transposition of the great arteries with a systemic right ventricle (RV), and congenital aortic stenosis. For Group B patients, polymorphic VT and ventricular fibrillation account for a higher proportion of VA. The prognostic value of programmed ventricular stimulation is less well established, and catheter ablation plays a less prominent role. As cardiomyopathies evolve over time, pathophysiological mechanisms for VA among Groups A and B become increasingly blurred.


Assuntos
Anomalia de Ebstein , Cardiopatias Congênitas , Taquicardia Ventricular , Transposição dos Grandes Vasos , Humanos , Adulto , Cardiopatias Congênitas/complicações , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia
15.
J Phys Chem Lett ; 14(33): 7574-7580, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37589653

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is enabled by local surface plasmon resonances (LSPRs) in metallic nanogaps. When SERS is excited by direct illumination of the nanogap, the background heating of the lattice and electrons can prevent further manipulation of the molecules. To overcome this issue, we report SERS in electromigrated gold molecular junctions excited remotely: surface plasmon polaritons (SPPs) are excited at nearby gratings, propagate to the junction, and couple to the local nanogap plasmon modes. Like direct excitation, remote excitation of the nanogap can generate both SERS emission and an open-circuit photovoltage (OCPV). We compare the SERS intensity and the OCPV in both direct and remote illumination configurations. SERS spectra obtained by remote excitation are much more stable than those obtained through direct excitation when the photon count rates are comparable. By statistical analysis of 33 devices, the coupling efficiency of remote excitation is calculated to be around 10%, consistent with the simulated energy flow.

16.
Heart Rhythm ; 20(12): 1739-1749, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37390910

RESUMO

BACKGROUND: Ventricular pacing can cause myocardial dysfunction, but how lead anchoring to the myocardium affects function has not been studied. OBJECTIVE: The purpose of this study was to evaluate patterns of regional and global ventricular function in patients with a ventricular lead using cine cardiac computed tomography (CCT) and histology. METHODS: This was a single-center retrospective study with 2 groups of patients with a ventricular lead: (1) those who underwent cine CCT from September 2020 to June 2021 and (2) those whose cardiac specimen was analyzed histologically. Regional wall motion abnormalities on CCT were assessed in relation to lead characteristics. RESULTS: For the CCT group, 122 ventricular lead insertion sites were analyzed in 43 patients (47% female; median age 19 years; range 3-57 years). Regional wall motion abnormalities were present at 51 of 122 lead insertion sites (42%) in 23 of 43 patients (53%). The prevalence of a lead insertion-associated regional wall motion abnormality was higher with active pacing (55% vs 18%; P < .001). Patients with lead insertion-associated regional wall motion abnormalities had a lower systemic ventricular ejection fraction (median 38% vs 53%; P < .001) than did those without regional wall motion abnormalities. For the histology group, 3 patients with 10 epicardial lead insertion sites were studied. Myocardial compression, fibrosis, and calcifications were commonly present directly under active leads. CONCLUSION: Lead insertion site-associated regional wall motion abnormalities are common and associated with systemic ventricular dysfunction. Histopathological alterations including myocardial compression, fibrosis, and calcifications beneath active leads may explain this finding.


Assuntos
Miocárdio , Marca-Passo Artificial , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Estudos Retrospectivos , Miocárdio/patologia , Coração , Marca-Passo Artificial/efeitos adversos , Fibrose
17.
Cardiovasc Pathol ; 65: 107528, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36841268

RESUMO

Formalin-fixed whole heart specimens are essential for studying the anatomy of congenital heart defects. Because of the improvement in diagnostic imaging and treatment, and cultural transition, heart specimens with congenital heart defects have become more and more rare and irreplaceable but are at risk of accidental deterioration through dehydration during long-term storage. In this article, we share our experience in reconditioning our inadvertently dehydrated heart specimens using a simple Formol-Glycerol solution that allowed for rehydration and recovery of such specimens.


Assuntos
Formaldeído , Cardiopatias Congênitas , Humanos , Glicerol , Coração
18.
JACC Case Rep ; 6: 101704, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36704056

RESUMO

Spontaneous coronary artery dissection in infants is a rare phenomenon. We present 2 neonates with severe ventricular dysfunction due to coronary artery dissection. Neither patient had evidence of extracardiac fibromuscular dysplasia or other comorbidities that would explain the presentation. (Level of Difficulty: Advanced.).

19.
Cardiovasc Res ; 119(1): 302-315, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35020813

RESUMO

AIMS: Bioprosthetic heart valves (BHVs), made from glutaraldehyde-fixed heterograft materials, are subject to more rapid structural valve degeneration (SVD) in paediatric and young adult patients. Differences in blood biochemistries and propensity for disease accelerate SVD in these patients, which results in multiple re-operations with compounding risks. The goal of this study is to investigate the mechanisms of BHV biomaterial degeneration and present models for studying SVD in young patients and juvenile animal models. METHODS AND RESULTS: We studied SVD in clinical BHV explants from paediatric and young adult patients, juvenile sheep implantation model, rat subcutaneous implants, and an ex vivo serum incubation model. BHV biomaterials were analysed for calcification, collagen microstructure (alignment and crimp), and crosslinking density. Serum markers of calcification and tissue crosslinking were compared between young and adult subjects. We demonstrated that immature subjects were more susceptible to calcification, microstructural changes, and advanced glycation end products formation. In vivo and ex vivo studies comparing immature and mature subjects mirrored SVD in clinical observations. The interaction between host serum and BHV biomaterials leads to significant structural and biochemical changes which impact their functions. CONCLUSIONS: There is an increased risk for accelerated SVD in younger subjects, both experimental animals and patients. Increased calcification, altered collagen microstructure with loss of alignment and increased crimp periods, and increased crosslinking are three main characteristics in BHV explants from young subjects leading to SVD. Together, our studies establish a basis for assessing the increased susceptibility of BHV biomaterials to accelerated SVD in young patients.


Assuntos
Bioprótese , Calcinose , Próteses Valvulares Cardíacas , Animais , Ratos , Ovinos , Valvas Cardíacas , Materiais Biocompatíveis , Colágeno
20.
Pediatr Cardiol ; 44(1): 245-248, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36178496

RESUMO

A 2-month-old male infant, born premature with a birth weight of 865 g, was found to have a tricuspid valve mass mimicking thrombus and vegetation by echocardiogram on the fourth day of life. The patient was treated with antibiotics and anticoagulation with no change in the size of the mass on serial follow-up echocardiography. The patient died of severe pulmonary vein stenosis and complex neurological disability. Postmortem cardiac examination revealed numerous cardiac blood cysts with two dominant ones (1.6 and 1.5 mm) on the septal leaflet of the tricuspid valve, which based on the location and position corresponded to the suspected vegetation and thrombus on imaging. Cardiac blood cysts on valve leaflets are a common incidental finding during autopsy within the first 6 months of life; however, they are rarely detected on imaging because of their minute size, often < 0.5 mm. In this case, the sizable blood cysts were thought to represent thrombus or vegetation on echocardiogram, which influenced the patient management.


Assuntos
Cistos , Trombose , Lactente , Recém-Nascido , Masculino , Humanos , Valva Tricúspide/diagnóstico por imagem , Ecocardiografia , Cistos/diagnóstico por imagem , Trombose/diagnóstico por imagem , Coagulação Sanguínea
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