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1.
Eur J Orthod ; 46(2)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376494

RESUMO

BACKGROUND: Facial appearance plays a significant role in the success of social interactions. There is a limited amount of evidence investigating the influence of combined orthodontic-orthognathic surgical treatment on the social judgments of lay people. OBJECTIVE: The aim of this study was to investigate whether changes in facial appearance following orthognathic surgery alter the social judgements made by lay people. ETHICAL APPROVAL: Ethical approval was granted from the University of Sheffield School of Clinical Dentistry Research Ethics Committee on 17th August 2020 (Reference: 033775). MATERIALS AND METHODS: This cross-sectional, web-based survey involved clinical photographs of six Caucasian female patients pre- and post-combined orthodontic-orthognathic treatment. Three patients had a pre-treatment class 2 skeletal pattern, and three patients had a pre-treatment class 3 skeletal pattern. Staff and students at the University of Sheffield, UK were invited to evaluate five personality traits: (i) friendliness, (ii) intelligence, (iii) attractiveness, (iv) self-confidence, and (5) trustworthiness using a 5-point Likert scale. The trait scores were summed to obtain a total social judgement score, and a paired t-test was used to compare the total scores from pre- and post-treatment images. RESULTS: There were 261 responses to the survey of which 181 (75%) were completed fully. The total social judgement scores from after treatment images were higher compared with the pre-treatment images (mean diff 1.6; P < .001) indicating more positive social judgements. The improvements in perceived social judgments were more notable for class 3 patients (mean diff 2.7) compared to class 2 patients (mean diff 0.7). CONCLUSION: Social judgement scores were higher (more positive) from post-treatment images of patient faces than their pre-treatment images. The findings highlight the possible indirect benefits combined orthodontic-orthognathic surgical treatment may have on an individual in a social setting.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Feminino , Julgamento , Estudos Transversais , Assistência Odontológica
2.
Am Heart J ; 266: 149-158, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37777041

RESUMO

BACKGROUND: For patients with nonischemic cardiomyopathy (NICM), current guidelines recommend implantable cardioverter defibrillators (ICD) when left ventricular ejection fraction (LVEF) is ≤35%, but the DANISH trial failed to confirm that ICDs reduced all-cause mortality for such patients. Circumstantial evidence suggests that scar on CMR is predictive of sudden and arrhythmic death in this population. The presence of myocardial scar identified by cardiac magnetic resonance imaging (CMR) in patients with NICM and an LVEF ≤35% might identify patients at higher risk of sudden arrhythmic death, for whom an ICD is more likely to reduce all-cause mortality. METHODS/DESIGN: The BRITISH trial is a prospective, multicenter, randomized controlled trial aiming to enrol 1,252 patients with NICM and an LVEF ≤35%. Patients with a nonischemic scar on CMR will be randomized to either: (1) ICD, with or without cardiac resynchronization (CRT-D), or (2) implantable loop recorder (ILR) or cardiac resynchronization (CRT-P). Patients who are screened for the trial but are found not to be eligible, predominantly due to an absence of scar or those who decline to be randomized will be enrolled in an observational registry. The primary endpoint is all-cause mortality, which we plan to assess at 3 years after the last participant is randomized. Secondary endpoints include clinical outcomes, appropriate and inappropriate device therapies, symptom severity and well-being, device-related complications, and analysis of the primary endpoint by subgroups with other risk markers. CONCLUSION: The BRITISH trial will assess whether the use of CMR-defined scar to direct ICD implantation in patients with NICM and an LVEF ≤35% is associated with a reduction in mortality.


Assuntos
Cardiomiopatias , Desfibriladores Implantáveis , Insuficiência Cardíaca Sistólica , Humanos , Volume Sistólico , Cicatriz/complicações , Benchmarking , Estudos Prospectivos , Função Ventricular Esquerda , Cardiomiopatias/complicações , Cardiomiopatias/diagnóstico , Cardiomiopatias/terapia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Fatores de Risco , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
3.
J Orthod ; 49(1): 24-31, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34308713

RESUMO

OBJECTIVE: To evaluate the impact of the coronavirus pandemic on patients in active orthodontic treatment. DESIGN: Digital online survey. SETTING: Two secondary care orthodontic departments in the United Kingdom. PARTICIPANTS: A prospective convenience sample of 103 patients in active orthodontic treatment. METHODS: A 12-item questionnaire developed using the platform SurveyMonkey was used to assess the following: (1) patient's feelings towards attending their orthodontic appointments; (2) their desire to continue with their treatment; (3) how many patients encountered problems with their appliance during the lockdown; (4) how patients sought help during the first national lockdown period; and (5) any other concerns regarding impact on their orthodontic treatment. RESULTS: A total of 103 participants responses were collected over a four-week period across two departments. Of them, 45% required a face-to-face appointment to solve a problem with their appliance; 45% of patients who had problems with their orthodontic appliance were able to resolve the issue through digital means either via telephone/email advice from their provider or from accessing help via the Internet; and 99% of patients wanted to continue with their orthodontic treatment. CONCLUSION: Our study has shown that a significantly higher percentage of patients are more concerned regarding attending face-to-face appointments after the first national lockdown due to the coronavirus pandemic. Providers of orthodontic care should ensure they support their patients by providing digital support and adopt virtual means of managing emergency cases patients in the event of any further imposed national or local lockdowns. Furthermore, access and availability of emergency face-to-face orthodontic care is necessary for many patients in active orthodontic treatment.


Assuntos
COVID-19 , Pandemias , Controle de Doenças Transmissíveis , Humanos , Estudos Prospectivos , SARS-CoV-2 , Atenção Secundária à Saúde
4.
J Cardiovasc Magn Reson ; 22(1): 31, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32375896

RESUMO

BACKGROUND: The T1 Mapping and Extracellular volume (ECV) Standardization (T1MES) program explored T1 mapping quality assurance using a purpose-developed phantom with Food and Drug Administration (FDA) and Conformité Européenne (CE) regulatory clearance. We report T1 measurement repeatability across centers describing sequence, magnet, and vendor performance. METHODS: Phantoms batch-manufactured in August 2015 underwent 2 years of structural imaging, B0 and B1, and "reference" slow T1 testing. Temperature dependency was evaluated by the United States National Institute of Standards and Technology and by the German Physikalisch-Technische Bundesanstalt. Center-specific T1 mapping repeatability (maximum one scan per week to minimum one per quarter year) was assessed over mean 358 (maximum 1161) days on 34 1.5 T and 22 3 T magnets using multiple T1 mapping sequences. Image and temperature data were analyzed semi-automatically. Repeatability of serial T1 was evaluated in terms of coefficient of variation (CoV), and linear mixed models were constructed to study the interplay of some of the known sources of T1 variation. RESULTS: Over 2 years, phantom gel integrity remained intact (no rips/tears), B0 and B1 homogenous, and "reference" T1 stable compared to baseline (% change at 1.5 T, 1.95 ± 1.39%; 3 T, 2.22 ± 1.44%). Per degrees Celsius, 1.5 T, T1 (MOLLI 5s(3s)3s) increased by 11.4 ms in long native blood tubes and decreased by 1.2 ms in short post-contrast myocardium tubes. Agreement of estimated T1 times with "reference" T1 was similar across Siemens and Philips CMR systems at both field strengths (adjusted R2 ranges for both field strengths, 0.99-1.00). Over 1 year, many 1.5 T and 3 T sequences/magnets were repeatable with mean CoVs < 1 and 2% respectively. Repeatability was narrower for 1.5 T over 3 T. Within T1MES repeatability for native T1 was narrow for several sequences, for example, at 1.5 T, Siemens MOLLI 5s(3s)3s prototype number 448B (mean CoV = 0.27%) and Philips modified Look-Locker inversion recovery (MOLLI) 3s(3s)5s (CoV 0.54%), and at 3 T, Philips MOLLI 3b(3s)5b (CoV 0.33%) and Siemens shortened MOLLI (ShMOLLI) prototype 780C (CoV 0.69%). After adjusting for temperature and field strength, it was found that the T1 mapping sequence and scanner software version (both P < 0.001 at 1.5 T and 3 T), and to a lesser extent the scanner model (P = 0.011, 1.5 T only), had the greatest influence on T1 across multiple centers. CONCLUSION: The T1MES CE/FDA approved phantom is a robust quality assurance device. In a multi-center setting, T1 mapping had performance differences between field strengths, sequences, scanner software versions, and manufacturers. However, several specific combinations of field strength, sequence, and scanner are highly repeatable, and thus, have potential to provide standardized assessment of T1 times for clinical use, although temperature correction is required for native T1 tubes at least.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/normas , Imagens de Fantasmas/normas , Consenso , Humanos , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
5.
J Adhes Dent ; 20(3): 205-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854993

RESUMO

PURPOSE: This in vitro study aimed to evaluate the shear bond strength (SBS) of particulate filler composite (PFC) to saliva- or water-contaminated fiber-reinforced composite (FRC). MATERIALS AND METHODS: One type of FRC substrate with semi-interpenetrating polymer matrix (semi-IPN) (everStick C&B) was used in this investigation. A microhybrid PFC (Filtek Z250) substrate served as control. Freshly cured PFC and FRC substrates were first subjected to different contamination and surface cleaning treatments, then the microhybrid PFC restorative material (Filtek Z250) was built up on the substrates in 2-mm increments and light cured. Uncontaminated and saliva- or water-contaminated substrate surfaces were either left untreated or were cleaned via phosphoric acid etching or water spray accompanied with or without adhesive composite application prior applying the adherent PFC material. SBS was evaluated after thermocycling the specimens (6000 cycles, 5°C and 55°C). RESULTS: Three-way ANOVA showed that both the surface contamination and the surface treatment signficantly affected the bond strength (p < 0.05). Saliva contamination reduced the SBS more than did the water contamination. SBS loss after saliva contamination was 73.7% and 31.3% for PFC and FRC, respectively. After water contamination, SBS loss was 17.2% and 13.3% for PFC and FRC, respectively. The type of surface treatment was significant for PFC (p < 0.05), but not for FRC (p = 0.572). CONCLUSION: Upon contamination of freshly cured PFC or semi-IPN FRC, surfaces should be re-prepared via phosphoric acid etching, water cleaning, drying, and application of adhesive composite in order to recover optimal bond strength.


Assuntos
Colagem Dentária , Saliva , Resinas Compostas , Teste de Materiais , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Água
6.
J Orthod ; 44(3): 174-182, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28708012

RESUMO

OBJECTIVES: To explore the accessibility, usability and relevance of the British Orthodontic Society (BOS) online information resource (OIR), Your Jaw Surgery. DESIGN: Qualitative, cross-sectional study. SETTING: 5 UK sites. PARTICIPANTS: Patients before, during and after treatment for non-cleft skeletal discrepancy. METHODS: Patients were identified at joint clinics and recruited after having time to view the OIR. Semi-structured interviews were conducted with 17 patients (aged 16-46 years). The interviews were transcribed and thematic analysis was undertaken using a framework approach. RESULTS: The main themes identified were the overall usefulness, personal relevance and positive perceptions of the OIR. The OIR was seen to be useful for patients considering treatment, and potentially useful for patients undergoing treatment. Participants were looking for a personally relevant resource that would give them the best possible idea of how they would look and feel after surgery. The OIR was perceived as trusted, positive and reassuring. CONCLUSIONS: Patients at different stages of treatment found the OIR helpful and reassuring. Clinicians may find it useful to direct patients to the OIR to complement a professional consultation, but should be aware that patients may perceive it as presenting a positive image of the long-term benefits of orthognathic surgery.


Assuntos
Procedimentos Cirúrgicos Ortognáticos , Sociedades Odontológicas , Adolescente , Adulto , Estudos Transversais , Etnicidade , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
7.
J Magn Reson Imaging ; 41(6): 1505-11, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25104503

RESUMO

PURPOSE: To explore the use and reproducibility of magnetic resonance-derived myocardial T1 mapping in patients with iron overload. MATERIALS AND METHODS: The research received ethics committee approval and all patients provided written informed consent. This was a prospective study of 88 patients and 67 healthy volunteers. Thirty-five patients underwent repeat scanning for reproducibility. T1 mapping used the shortened modified Look-Locker inversion recovery sequence (ShMOLLI) with a second, confirmatory MOLLI sequence in the reproducibility group. T2 * was performed using a commercially available sequence. The analysis of the T2 * interstudy reproducibility data was performed by two different research groups using two different methods. RESULTS: Myocardial T1 was lower in patients than healthy volunteers (836 ± 138 msec vs. 968 ± 32 msec, P < 0.0001). Myocardial T1 correlated with T2 * (R = 0.79, P < 0.0001). No patient with low T2 * had normal T1 , but 32% (n = 28) of cases characterized by a normal T2 * had low myocardial T1 . Interstudy reproducibility of either T1 sequence was significantly better than T2 *, with the results suggesting that the use of T1 in clinical trials could decrease potential sample sizes by 7-fold. CONCLUSION: Myocardial T1 mapping is an alternative method for cardiac iron quantification. T1 mapping shows the potential for improved detection of mild iron loading. The superior reproducibility of T1 has potential implications for clinical trial design and therapeutic monitoring.


Assuntos
Sobrecarga de Ferro/diagnóstico , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Sobrecarga de Ferro/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
8.
J Orthod ; 41(2): 88-97, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24521747

RESUMO

OBJECTIVES: To explore the views of potential orthognathic patients regarding the influence of the BOS Orthognathic DVD in their decision making process. DESIGN: Qualitative, cross-sectional study. SETTING: A UK dental teaching hospital. PARTICIPANTS: Patients considering orthognathic treatment. METHODS: New patients were recruited from orthognathic clinics following an initial consultation. After an appropriate time to view the DVD, in-depth interviews were conducted with 10 patients (aged 16-48 years) in their homes. Interviews explored the attitudes and perceptions that influenced decisions about surgery, with a focus on the role of the DVD in this process. The interviews were transcribed and a framework analysis was undertaken. RESULTS: The main themes identified were participant perceptions on the patient stories, use of images, the nature of the DVD itself and its usefulness in the decision making process. Participants reported they were heavily influenced by the patient stories. Virtual animations of surgery were seen as useful; whereas the before and after images of surgery were found to be disorientating. The design of the menu resulted in confusion or information being missed. The DVD was seen as a trusted resource, whereas the Internet was seen as biased, general and sensationalistic. CONCLUSIONS: The DVD gives trusted information that patients cannot obtain or process from professional sources or the Internet. If used properly it can have a role in the decision making process, but should be seen within the context of other influences on the patient. This research has highlighted some aspects of the DVD that could be improved upon.


Assuntos
Tomada de Decisões , Ortodontia , Procedimentos Cirúrgicos Ortognáticos , Educação de Pacientes como Assunto , Sociedades Odontológicas , Gravação de Videodisco , Adolescente , Adulto , Atitude Frente a Saúde , Informação de Saúde ao Consumidor , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Internet , Masculino , Má Oclusão Classe II de Angle/psicologia , Má Oclusão Classe III de Angle/psicologia , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Ortognáticos/psicologia , Estudos Prospectivos , Pesquisa Qualitativa , Reino Unido , Adulto Jovem
9.
Radiology ; 269(2): 396-403, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23878282

RESUMO

PURPOSE: To develop and validate equilibrium contrast material-enhanced computed tomography (CT) to measure myocardial extracellular volume (ECV) fraction by using a histologic reference standard and to compare equilibrium CT with equilibrium contrast-enhanced magnetic resonance (MR) imaging. MATERIALS AND METHODS: A local ethics committee approved the study, and all subjects gave fully informed written consent. An equilibrium CT protocol was developed using iohexol at 300 mg of iodine per milliliter (bolus of 1 mg per kilogram of body weight administered at a rate of 3 mL/sec, followed immediately by an infusion of 1.88 mL/kg per hour with CT imaging before and at 25 minutes after injection of bolus of contrast agent) and ECV within the myocardial septum measured using both equilibrium CT and equilibrium MR imaging in patients with severe aortic stenosis. Biopsy samples of the myocardial septum collected during valve replacement surgery were used for histologic quantification of extracellular fibrosis with picrosirius red staining. Equilibrium CT- and equilibrium MR imaging-derived ECV measurements were compared with histologically quantified fibrosis by using Pearson correlation. Agreement between equilibrium CT and equilibrium MR imaging was assessed by using Bland-Altman comparison. RESULTS: Twenty-three patients (16 male, seven female; mean age, 70.8 years; standard deviation, 8.3) were recruited. The mean percentage of histologic fibrosis was 18% (intersubject range, 5%-40%). There was a significant correlation between both equilibrium CT- and equilibrium MR imaging-derived ECV and percentage of histologic fibrosis (r = 0.71 [P < .001] and r = 0.84 [P < .0001], respectively). Equilibrium CT-derived ECV was significantly correlated to equilibrium MR imaging-derived ECV (r = 0.73). CONCLUSION: ECV measured by using equilibrium CT in patients with aortic stenosis correlates with histologic quantification of myocardial fibrosis and with ECV derived by using equilibrium MR imaging.


Assuntos
Fibrose Endomiocárdica/diagnóstico por imagem , Matriz Extracelular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Biópsia , Meios de Contraste , Fibrose Endomiocárdica/patologia , Matriz Extracelular/patologia , Feminino , Humanos , Iohexol , Imageamento por Ressonância Magnética/métodos , Masculino , Coloração e Rotulagem
10.
Radiology ; 268(3): 858-64, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23674785

RESUMO

PURPOSE: To investigate equilibrium contrast material-enhanced magnetic resonance (MR) imaging measurement of extracellular volume (ECV) fraction within healthy abdominal tissues and to test the hypotheses that tissue ECV in systemic amyloid light-chain (AL) amyloidosis is greater than in healthy patients and show that this increase correlates with organ amyloid burden. MATERIALS AND METHODS: A local ethics committee approved the study and all patients gave written informed consent. Forty healthy volunteers (18 men, 22 women; median age, 43 years; age range, 24-88 years) and 67 patients with AL amyloidosis (43 men, 24 women; median age, 65 years; age range, 38-81 years) underwent equilibrium MR imaging of the upper abdomen. ECV was measured in the liver, spleen, and paravertebral muscle. Patients with amyloidosis also underwent serum amyloid P (SAP) component scintigraphy so that specific organ involvement by amyloid could be scored. Variation in ECV between tissues was assessed by using a Friedman Test. Tissue ECV in healthy and amyloidosis groups were compared by using a Mann-Whitney U test. Spearman correlation was used to test for an association between the organ SAP score and ECV. RESULTS: ECV measured at equilibrium MR imaging varied significantly between organs in healthy volunteers (χ(2) = 31.0; P < .001). ECV was highest in the spleen (0.34), followed by liver (0.29) and muscle (0.09). ECVs measured within the spleen (0.39; P< .001), liver (0.31; P = .005), and muscle (0.16; P< .001) were significantly higher in patients with amyloidosis than in healthy control subjects. ECV measured in the liver and spleen showed increasing organ amyloid burden assessed at SAP scintigraphy (liver, rs = 0.54; spleen, rs = 0.57). CONCLUSION: Equilibrium MR imaging can be used to define ECV within healthy tissues. ECV is increased in amyloidosis compared with healthy tissues, and this increase correlates with rising tissue amyloid burden.


Assuntos
Amiloidose/patologia , Líquido Extracelular/citologia , Aumento da Imagem/métodos , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Meglumina , Compostos Organometálicos , Baço/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
11.
J Cardiovasc Magn Reson ; 15: 16, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23398958

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) is commonly used in patients with suspected arrhythmogenic right ventricular cardiomyopathy (ARVC) based on ECG, echocardiogram and Holter. However, various diseases may present with clinical characteristics resembling ARVC causing diagnostic dilemmas. The aim of this study was to explore the role of CMR in the differential diagnosis of patients with suspected ARVC. METHODS: 657 CMR referrals suspicious for ARVC in a single tertiary referral centre were analysed. Standardized CMR imaging protocols for ARVC were performed. Potential ARVC mimics were grouped into: 1) displacement of the heart, 2) right ventricular overload, and 3) non ARVC-like cardiac scarring. For each, a judgment of clinical impact was made. RESULTS: Twenty patients (3.0%) fulfilled imaging ARVC criteria. Thirty (4.6%) had a potential ARVC mimic, of which 25 (3.8%) were considered clinically important: cardiac displacement (n=17), RV overload (n=7) and non-ARVC like myocardial scarring (n=4). One patient had two mimics; one patient had dual pathology with important mimic and ARVC. RV overload and scarring conditions were always thought clinically important whilst the importance of cardiac displacement depended on the degree of displacement from severe (partial absence of pericardium) to epiphenomenon (minor kyphoscoliosis). CONCLUSIONS: Some patients referred for CMR with suspected ARVC fulfil ARVC imaging criteria (3%) but more have otherwise unrecognised diseases (4.6%) mimicking potentially ARVC. Clinical assessment should reflect this, emphasising the assessment and/or exclusion of potential mimics in parallel with the detection of ARVC major and minor criteria.


Assuntos
Displasia Arritmogênica Ventricular Direita/diagnóstico , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Displasia Arritmogênica Ventricular Direita/patologia , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Diagnóstico Diferencial , Eletrocardiografia , Humanos , Londres , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Centros de Atenção Terciária , Função Ventricular Esquerda , Função Ventricular Direita
12.
J Cardiovasc Magn Reson ; 15: 36, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23663522

RESUMO

BACKGROUND: Left ventricular noncompaction (LVNC) is a myocardial disorder characterized by excessive left ventricular (LV) trabeculae. Current methods for quantification of LV trabeculae have limitations. The aim of this study is to describe a novel technique for quantifying LV trabeculation using cardiovascular magnetic resonance (CMR) and fractal geometry. Observing that trabeculae appear complex and irregular, we hypothesize that measuring the fractal dimension (FD) of the endocardial border provides a quantitative parameter that can be used to distinguish normal from abnormal trabecular patterns. METHODS: Fractal analysis is a method of quantifying complex geometric patterns in biological structures. The resulting FD is a unitless measure index of how completely the object fills space. FD increases with increased structural complexity. LV FD was measured using a box-counting method on CMR short-axis cine stacks. Three groups were studied: LVNC (defined by Jenni criteria), n=30(age 41±13; men, 16); healthy whites, n=75(age, 46±16; men, 36); healthy blacks, n=30(age, 40±11; men, 15). RESULTS: In healthy volunteers FD varied in a characteristic pattern from base to apex along the LV. This pattern was altered in LVNC where apical FD were abnormally elevated. In healthy volunteers, blacks had higher FD than whites in the apical third of the LV (maximal apical FD: 1.253±0.005 vs. 1.235±0.004, p<0.01) (mean±s.e.m.). Comparing LVNC with healthy volunteers, maximal apical FD was higher in LVNC (1.392±0.010, p<0.00001). The fractal method was more accurate and reproducible (ICC, 0.97 and 0.96 for intra and inter-observer readings) than two other CMR criteria for LVNC (Petersen and Jacquier). CONCLUSIONS: FD is higher in LVNC patients compared to healthy volunteers and is higher in healthy blacks than in whites. Fractal analysis provides a quantitative measure of trabeculation and has high reproducibility and accuracy for LVNC diagnosis when compared to current CMR criteria.


Assuntos
Fractais , Interpretação de Imagem Assistida por Computador/métodos , Miocárdio Ventricular não Compactado Isolado/patologia , Imagem Cinética por Ressonância Magnética/métodos , Disfunção Ventricular Esquerda/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , População Negra/estatística & dados numéricos , Distribuição de Qui-Quadrado , Ecocardiografia , Humanos , Miocárdio Ventricular não Compactado Isolado/etnologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/etnologia , População Branca/estatística & dados numéricos
13.
J Cardiovasc Magn Reson ; 14: 88, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23272651

RESUMO

BACKGROUND: Myocardial extracellular volume (ECV) is elevated in fibrosis or infiltration and can be quantified by measuring the haematocrit with pre and post contrast T1 at sufficient contrast equilibrium. Equilibrium CMR (EQ-CMR), using a bolus-infusion protocol, has been shown to provide robust measurements of ECV using a multibreath-hold T1 pulse sequence. Newer, faster sequences for T1 mapping promise whole heart coverage and improved clinical utility, but have not been validated. METHODS: Multibreathhold T1 quantification with heart rate correction and single breath-hold T1 mapping using Shortened Modified Look-Locker Inversion recovery (ShMOLLI) were used in equilibrium contrast CMR to generate ECV values and compared in 3 ways.Firstly, both techniques were compared in a spectrum of disease with variable ECV expansion (n=100, 50 healthy volunteers, 12 patients with hypertrophic cardiomyopathy, 18 with severe aortic stenosis, 20 with amyloid). Secondly, both techniques were correlated to human histological collagen volume fraction (CVF%, n=18, severe aortic stenosis biopsies). Thirdly, an assessment of test:retest reproducibility of the 2 CMR techniques was performed 1 week apart in individuals with widely different ECVs (n=10 healthy volunteers, n=7 amyloid patients). RESULTS: More patients were able to perform ShMOLLI than the multibreath-hold technique (6% unable to breath-hold). ECV calculated by multibreath-hold T1 and ShMOLLI showed strong correlation (r(2)=0.892), little bias (bias -2.2%, 95%CI -8.9% to 4.6%) and good agreement (ICC 0.922, range 0.802 to 0.961, p<0.0001). ECV correlated with histological CVF% by multibreath-hold ECV (r(2)= 0.589) but better by ShMOLLI ECV (r(2)= 0.685). Inter-study reproducibility demonstrated that ShMOLLI ECV trended towards greater reproducibility than the multibreath-hold ECV, although this did not reach statistical significance (95%CI -4.9% to 5.4% versus 95%CI -6.4% to 7.3% respectively, p=0.21). CONCLUSIONS: ECV quantification by single breath-hold ShMOLLI T1 mapping can measure ECV by EQ-CMR across the spectrum of interstitial expansion. It is procedurally better tolerated, slightly more reproducible and better correlates with histology compared to the older multibreath-hold FLASH techniques.


Assuntos
Amiloidose/diagnóstico , Estenose da Valva Aórtica/diagnóstico , Suspensão da Respiração , Cardiomiopatia Hipertrófica/diagnóstico , Meios de Contraste , Compostos Heterocíclicos , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Compostos Organometálicos , Adulto , Idoso , Amiloidose/metabolismo , Amiloidose/patologia , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Biópsia , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/patologia , Estudos de Casos e Controles , Colágeno/análise , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/química , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
14.
ESC Heart Fail ; 9(1): 48-56, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34882989

RESUMO

AIMS: The CardioMEMS HF System Post-Market Study (COAST) was designed to evaluate the safety, effectiveness, and feasibility of haemodynamic-guided heart failure (HF) management using a small sensor implanted in the pulmonary artery of New York Heart Association (NYHA) Class III HF patients in the UK, Europe, and Australia. METHODS AND RESULTS: COAST is a prospective, international, multicentre, open-label clinical study (NCT02954341). The primary clinical endpoint compares annualized HF hospitalization rates after 1 year of haemodynamic-guided management vs. the year prior to sensor implantation in patients with NYHA Class III symptoms and a previous HF hospitalization. The primary safety endpoints assess freedom from device/system-related complications and pressure sensor failure after 2 years. Results from the first 100 patients implanted at 14 out of the 15 participating centres in the UK are reported here. At baseline, all patients were in NYHA Class III, 70% were male, mean age was 69 ± 12 years, and 39% had an aetiology of ischaemic cardiomyopathy. The annualized HF hospitalization rate after 12 months was 82% lower [95% confidence interval 72-88%] than the previous 12 months (0.27 vs. 1.52 events/patient-year, respectively, P < 0.0001). Freedom from device/system-related complications and pressure sensor failure at 2 years was 100% and 99%, respectively. CONCLUSIONS: Remote haemodynamic-guided HF management, using frequent assessment of pulmonary artery pressures, was successfully implemented at 14 specialist centres in the UK. Haemodynamic-guided HF management was safe and significantly reduced hospitalization in a group of high-risk patients. These results support implementation of this innovative remote management strategy to improve outcome for patients with symptomatic HF. Clinical registration number: ClinicalTrials.gov identifier: NCT02954341.


Assuntos
Insuficiência Cardíaca , Medicina Estatal , Idoso , Idoso de 80 Anos ou mais , Monitorização Ambulatorial da Pressão Arterial/métodos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reino Unido/epidemiologia
15.
Circulation ; 122(2): 138-44, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20585010

RESUMO

BACKGROUND: Diffuse myocardial fibrosis is a final end point in most cardiac diseases. It is missed by the cardiovascular magnetic resonance (CMR) late gadolinium enhancement technique. Currently, quantifying diffuse myocardial fibrosis requires invasive biopsy, with inherent risk and sampling error. We have developed a robust and noninvasive technique, equilibrium contrast CMR (EQ-CMR) to quantify diffuse fibrosis and have validated it against the current gold standard of surgical myocardial biopsy. METHODS AND RESULTS: The 3 principles of EQ-CMR are a bolus of extracellular gadolinium contrast followed by continuous infusion to achieve equilibrium; a blood sample to measure blood volume of distribution (1-hematocrit); and CMR to measure pre- and postequilibrium T1 (with heart rate correction). The myocardial volume of distribution is calculated, reflecting diffuse myocardial fibrosis. Clinical validation occurred in patients undergoing aortic valve replacement for aortic stenosis or myectomy in hypertrophic cardiomyopathy (n=18 and n=8, respectively). Surgical biopsies were analyzed for picrosirius red fibrosis quantification on histology. The mean histological fibrosis was 20.5+/-11% in aortic stenosis and 17.1+/-7.4% in hypertrophic cardiomyopathy. EQ-CMR correlated strongly with biopsy histological fibrosis: aortic stenosis, r(2)=0.86, Kendall Tau coefficient (T)=0.71, P<0.001; hypertrophic cardiomyopathy, r(2)=0.62, T=0.52, P=0.08; combined r(2)=0.80, T=0.67, P<0.001. CONCLUSIONS: We have developed and validated a new technique, EQ-CMR, to measure diffuse myocardial fibrosis as an add-on to a standard CMR scan, which allows for the noninvasive quantification of the diffuse fibrosis burden in myocardial diseases.


Assuntos
Estenose da Valva Aórtica/patologia , Cardiomiopatia Hipertrófica/patologia , Meios de Contraste/administração & dosagem , Fibrose Endomiocárdica/patologia , Gadolínio DTPA/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Estenose da Valva Aórtica/cirurgia , Biópsia , Cardiomiopatia Hipertrófica/cirurgia , Feminino , Humanos , Masculino
16.
Balkan Med J ; 37(5): 260-268, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32319279

RESUMO

Background: One of the most important techniques of cardiac magnetic resonance in assessment of coronary heart diseases is adenosine stress myocardial first-pass perfusion imaging. Using this imaging method, there should be an adequate response to the drug adenosine to make an accurate evaluation. The conventional signs of drug response are not always observed and are often subjective. Methods based on splenic perfusion might possess limitations as well. Therefore, T1 mapping presents as a novel, quantitative and reliable method. There are several studies analyzing this newly discovered property of different T1 mapping sequences. However most of these studies are enrolling only one of the techniques. Aims: To compare modified look-locker inversion recovery and shortened modified look-locker inversion recovery sequences in terms of T1 reactivity and to determine the relationship between T1 reactivity and conventional stress adequacy assessment methods in adenosine stress perfusion cardiac magnetic resonance. Study Design: A cross-sectional study using STARD reporting guideline. Methods: Thirty-four consecutive patients, who were referred for adenosine stress perfusion cardiac magnetic resonance with suspect of myocardial ischemia, were prospectively enrolled into the study. Four patients were disqualified, and thirty patients were included in the final analysis. Using both modified look-locker inversion recovery and shortened modified look-locker inversion recovery, midventricular short axis slices of T1 maps were acquired at rest and during peak adenosine stress before gadolinium administration. Then, they were divided into six segments according to the 17-segment model proposed by the American Heart Association, and separate measurements were made from each segment. Mean rest and mean stress T1 values of remote, ischemic, and infarcted myocardium were calculated individually per subject. During adenosine administration, patients' heart rates and blood pressures are measured and recorded every one minute. Adenosine stress perfusion images were examined for the presence of splenic switch-off. Results: There was a significant difference between rest and stress T1 values of remote myocardium in both modified look-locker inversion recovery and shortened modified look-locker inversion recovery (p<0.001). In both modified look-locker inversion recovery and shortened modified look-locker inversion recovery there was no significant correlation between T1 reactivity and heart rates response (modified look-locker inversion recovery p=0.30, shortened modified look-locker inversion recovery p=0.10), blood pressures response (modified look-locker inversion recovery p=0.062, shortened modified look-locker inversion recovery p=0.078), splenic perfusion (modified look-locker inversion recovery p=0.35, shortened modified look-locker inversion recovery p=0.053). There was no statistically significant difference between modified look-locker inversion recovery and shortened modified look-locker inversion recovery regarding T1 reactivity of remote (p=0.330), ischemic (p=0.068), and infarcted (p=0.116) myocardium. Conclusion: T1 reactivity is independent of the other stress response signs and modified look-locker inversion recovery and shortened modified look-locker inversion recovery do not differ in terms of T1 reactivity.


Assuntos
Adenosina/administração & dosagem , Imageamento por Ressonância Magnética/normas , Imagem de Perfusão do Miocárdio/normas , Adenosina/farmacologia , Adenosina/uso terapêutico , Idoso , Análise de Variância , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Estudos Transversais , Teste de Esforço/métodos , Teste de Esforço/normas , Teste de Esforço/estatística & dados numéricos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Valor Preditivo dos Testes
17.
Heart ; 106(20): 1579-1585, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32690621

RESUMO

OBJECTIVE: To describe the population, heart failure (HF) diagnosis rate, and 1-year hospitalisation and mortality of patients with suspected HF and elevated N-terminal pro B-type natriuretic peptide (NTproBNP) investigated according to UK National Institute for Health and Care Excellence (NICE) guidelines. METHODS: NICE recommends patients with suspected HF, based on clinical presentation and elevated NTproBNP, are referred for specialist assessment and echocardiography. Patients should be seen within 2 weeks when NTproBNP is >2000 pg/mL (2-week pathway: 2WP) or within 6 weeks when NTproBNP is 400-2000 pg/mL (6-week pathway: 6WP). This is a retrospective, multicentre, observational study of consecutive patients with suspected HF referred from primary care between 2014 and 2016 to dedicated secondary care HF clinics based on the NICE 2WP and 6WP. Data were obtained from hospital records and episode statistics. Mortality and hospitalisation rates were calculated 1 year from NTproBNP measurement. RESULTS: 1271 patients (median age 80; IQR 73-85) were assessed, 680 (53%) of whom were female. 667 (53%) were referred on the 2WP and 604 (47%) on the 6WP. 698 (55%) were diagnosed with HF (369 HF with reduced ejection fraction) and 566 (45%) as not HF (NHF). 1-year mortality was 10% (n=129) and hospitalisation was 33% (n=413). Patients on the 2WP had higher mortality and hospitalisation rates than those on the 6WP, 14% vs 6% (p<0.001) and 38% vs 27% (p<0.001), respectively. All-cause mortality (11% vs 9%; p=0.306) and hospitalisation rates (35% vs 29%; p=0.128) did not differ between HF and NHF patients, respectively. CONCLUSIONS: Outcomes using the NICE approach of short waiting time targets for specialist assessment of patients with suspected HF and raised NTproBNP are not known. The model identifies an elderly population a high proportion of whom have HF. Irrespective of diagnosis, patients have high rates of adverse outcomes. These contemporary real-world data provide a platform for discussions with patients and shaping HF services.


Assuntos
Academias e Institutos/normas , Ecocardiografia/normas , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Guias de Prática Clínica como Assunto/normas , Encaminhamento e Consulta/normas , Medicina Estatal/normas , Listas de Espera , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Masculino , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Tempo para o Tratamento , Reino Unido , Regulação para Cima
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