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1.
BMJ Open Respir Res ; 9(1)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35297371

RESUMO

Machine learning (ML) holds great potential for predicting clinical outcomes in heterogeneous chronic respiratory diseases (CRD) affecting children, where timely individualised treatments offer opportunities for health optimisation. This paper identifies rate-limiting steps in ML prediction model development that impair clinical translation and discusses regulatory, clinical and ethical considerations for ML implementation. A scoping review of ML prediction models in paediatric CRDs was undertaken using the PRISMA extension scoping review guidelines. From 1209 results, 25 articles published between 2013 and 2021 were evaluated for features of a good clinical prediction model using the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines.Most of the studies were in asthma (80%), with few in cystic fibrosis (12%), bronchiolitis (4%) and childhood wheeze (4%). There were inconsistencies in model reporting and studies were limited by a lack of validation, and absence of equations or code for replication. Clinician involvement during ML model development is essential and diversity, equity and inclusion should be assessed at each step of the ML pipeline to ensure algorithms do not promote or amplify health disparities among marginalised groups. As ML prediction studies become more frequent, it is important that models are rigorously developed using published guidelines and take account of regulatory frameworks which depend on model complexity, patient safety, accountability and liability.


Assuntos
Lista de Checagem , Modelos Estatísticos , Algoritmos , Criança , Humanos , Aprendizado de Máquina , Prognóstico
2.
Nutr Neurosci ; 23(12): 983-992, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30794085

RESUMO

Objective: Habitual diet impacts mood and the human gastrointestinal (GI) microbiota. Yet, studies infrequently control for diet when evaluating associations between mood and GI microbiota. Accordingly, we aimed to investigate relationships among diet, GI microbiota, and mood in adults without mood disorders by conducting a cross-sectional examination of dietary intake, subjective emotional state, and fecal microbial taxa abundances. Methods: Adults (N = 133; 25-45 years of age) without physician-diagnosed mood disorders were studied. Fecal DNA was extracted, and the V4 region of the 16S rRNA gene was sequenced. Sequences were analyzed using QIIME2. Subjective mood state was assessed using the 42-item Depression, Anxiety, and Stress Scale (DASS-42). Habitual dietary intake was measured with the National Cancer Institute's Diet History Questionnaire II, and diet quality was evaluated with the 2010 Healthy Eating Index (HEI). Results: Relationships were observed between 28 bacterial taxa and DASS-42 scores. Sex-dependent associations were observed among 21 bacterial taxa and DASS-42 scores, including an inverse relationship between Anxiety scale scores and Bifidobacterium in females and an inverse relationship between Depression scale scores and Lactobacillus in males. HEI total fruit and dairy components were inversely associated with Depression and Stress scales, respectively. Conclusions: These results suggest GI microbes are related to mood in adults without diagnosed mood disorders and that these relationships differ by sex and are influenced by dietary fiber intake. Incorporating dietary intake data in gut-microbiota-brain studies may help clarify the roles of specific microbes and dietary components in mental health symptoms.


Assuntos
Dieta/psicologia , Emoções , Microbioma Gastrointestinal , Adulto , Afeto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Int J Artif Organs ; 42(10): 595-599, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31104546

RESUMO

In light of growing interest for three-dimensional printing technology in the cardiovascular community, this study focused on exploring the possibilities of providing training for cardiovascular three-dimensional printing in the context of a relevant international congress and providing considerations on the delivery of such courses. As a second objective, the study sought to capture preferences in relation to three-dimensional printing uses and set-ups from those attending the training session. A survey was administered to n = 30 professionals involved or interested in three-dimensional printing cardiovascular models following a specialised teaching session. Survey results suggest the potential for split training sessions, with a broader introduction for those with no prior experience in three-dimensional printing followed by a more in-depth and hands-on session. All participants agreed on the potential of the technology in all its applications, particularly for aiding decision-making around complex surgical or interventional cases. When exploring setting up an in-house three-dimensional printing service, the majority of participants reported that their centre was already equipped with an in-house facility or expressed a desire that such a facility should be available, with a minority preferring consigning models to an external third party for printing.


Assuntos
Atitude do Pessoal de Saúde , Cardiopatias Congênitas/cirurgia , Modelos Cardiovasculares , Impressão Tridimensional , Congressos como Assunto , Humanos , Inquéritos e Questionários
5.
Br J Radiol ; 92(1094): 20180389, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30325646

RESUMO

Three-dimensional (3D) printing technology in congenital cardiology and cardiac surgery has experienced a rapid development over the last decade. In presence of complex cardiac and extra-cardiac anatomies, the creation of a physical, patient-specific model is attractive to most clinicians. However, at the present time, there is still a lack of strong scientific evidence of the benefit of 3D models in clinical practice and only qualitative evaluation of the models has been used to investigate their clinical use. 3D models can be printed in rigid or flexible materials, and the original size can be augmented depending on the application the models are needed for. The most common applications of 3D models at present include procedural planning of complex surgical or interventional cases, in vitro simulation for research purposes, training and communication with patients and families. The aim of this pictorial review is to describe the basic principles of this technology and present its current and future applications.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas/patologia , Coração/anatomia & histologia , Modelos Anatômicos , Impressão Tridimensional , Cardiologia , Cardiopatias Congênitas/cirurgia , Humanos
6.
J Biomech ; 71: 236-244, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29482928

RESUMO

Patient-specific computational models are an established tool to support device development and test under clinically relevant boundary conditions. Potentially, such models could be used to aid the clinical decision-making process for percutaneous valve selection; however, their adoption in clinical practice is still limited to individual cases. To be fully informative, they should include patient-specific data on both anatomy and mechanics of the implantation site. In this work, fourteen patient-specific computational models for transcatheter aortic valve replacement (TAVR) with balloon-expandable Sapien XT devices were retrospectively developed to tune the material parameters of the implantation site mechanical model for the average TAVR population. Pre-procedural computed tomography (CT) images were post-processed to create the 3D patient-specific anatomy of the implantation site. Balloon valvuloplasty and device deployment were simulated with finite element (FE) analysis. Valve leaflets and aortic root were modelled as linear elastic materials, while calcification as elastoplastic. Material properties were initially selected from literature; then, a statistical analysis was designed to investigate the effect of each implantation site material parameter on the implanted stent diameter and thus identify the combination of material parameters for TAVR patients. These numerical models were validated against clinical data. The comparison between stent diameters measured from post-procedural fluoroscopy images and final computational results showed a mean difference of 2.5 ±â€¯3.9%. Moreover, the numerical model detected the presence of paravalvular leakage (PVL) in 79% of cases, as assessed by post-TAVR echocardiographic examination. The final aim was to increase accuracy and reliability of such computational tools for prospective clinical applications.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Modelagem Computacional Específica para o Paciente , Substituição da Valva Aórtica Transcateter/instrumentação , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/anatomia & histologia , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico por imagem , Valvuloplastia com Balão , Calcinose/diagnóstico por imagem , Calcinose/cirurgia , Ecocardiografia , Feminino , Análise de Elementos Finitos , Fluoroscopia , Humanos , Masculino , Reprodutibilidade dos Testes , Stents , Tomografia Computadorizada por Raios X
7.
Interface Focus ; 8(1): 20170021, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29285347

RESUMO

Patient-specific computational models have been extensively developed over the last decades and applied to investigate a wide range of cardiovascular problems. However, translation of these technologies into clinical applications, such as planning of medical procedures, has been limited to a few single case reports. Hence, the use of patient-specific models is still far from becoming a standard of care in clinical practice. The aim of this study is to describe our experience with a modelling framework that allows patient-specific simulations to be used for prediction of clinical outcomes. A cohort of 12 patients with congenital heart disease who were referred for percutaneous pulmonary valve implantation, stenting of aortic coarctation and surgical repair of double-outlet right ventricle was included in this study. Image data routinely acquired for clinical assessment were post-processed to set up patient-specific models and test device implantation and surgery. Finite-element and computational fluid dynamics analyses were run to assess feasibility of each intervention and provide some guidance. Results showed good agreement between simulations and clinical decision including feasibility, device choice and fluid-dynamic parameters. The promising results of this pilot study support translation of computer simulations as tools for personalization of cardiovascular treatments.

8.
Hypertension ; 69(3): 501-509, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28115510

RESUMO

Patients with repaired coarctation of the aorta are thought to have increased afterload due to abnormalities in vessel structure and function. We have developed a novel cardiovascular magnetic resonance protocol that allows assessment of central hemodynamics, including central aortic systolic blood pressure, resistance, total arterial compliance, pulse wave velocity, and wave reflections. The main study aims were to (1) characterize group differences in central aortic systolic blood pressure and peripheral systolic blood pressure, (2) comprehensively evaluate afterload (including wave reflections) in the 2 groups, and (3) identify possible biomarkers among covariates associated with elevated left ventricular mass (LVM). Fifty adult patients with repaired coarctation and 25 age- and sex-matched controls were recruited. Ascending aorta area and flow waveforms were obtained using a high temporal-resolution spiral phase-contrast cardiovascular magnetic resonance flow sequence. These data were used to derive central hemodynamics and to perform wave intensity analysis noninvasively. Covariates associated with LVM were assessed using multivariable linear regression analysis. There were no significant group differences (P≥0.1) in brachial systolic, mean, or diastolic BP. However central aortic systolic blood pressure was significantly higher in patients compared with controls (113 versus 107 mm Hg, P=0.002). Patients had reduced total arterial compliance, increased pulse wave velocity, and larger backward compression waves compared with controls. LVM index was significantly higher in patients than controls (72 versus 59 g/m2, P<0.0005). The magnitude of the backward compression waves was independently associated with variation in LVM (P=0.01). Using a novel, noninvasive hemodynamic assessment, we have shown abnormal conduit vessel function after coarctation of the aorta repair, including abnormal wave reflections that are associated with elevated LVM.


Assuntos
Coartação Aórtica/cirurgia , Pressão Sanguínea/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Complicações Pós-Operatórias , Resistência Vascular/fisiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Adulto , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Esquerda/etiologia , Angiografia por Ressonância Magnética , Masculino , Análise de Onda de Pulso , Fatores de Tempo , Adulto Jovem
9.
Eur Heart J Cardiovasc Imaging ; 18(8): 898-905, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27461210

RESUMO

AIMS: Cardiovascular magnetic resonance (CMR), using adenosine stress perfusion and late-gadolinium enhancement (LGE), is becoming the 'gold standard' non-invasive imaging modality in the assessment of adults with coronary artery disease (CAD). However, despite its proved feasibility in paediatric patients, clinical utility has not been demonstrated. Therefore, this study aims to establish the role of adenosine stress perfusion CMR as a screening test in paediatric patients with acquired or congenital CAD. METHODS AND RESULTS: A total of 58 paediatric patients underwent 61 consecutive clinically indicated coronary artery assessments for diagnostic and clinical decision-making purposes. The diagnosis was based on X-ray or computed tomography coronary angiography for anatomy, adenosine stress CMR imaging for myocardial perfusion and LGE for tissue characterization. Two studies were aborted because of unwanted side effects of adenosine stress, thus 59 studies were completed in 56 patients [median age 14.1 years (interquartile range 10.9-16.2)]. When compared with coronary anatomical imaging, adenosine stress perfusion CMR performed as follows: sensitivity 100% (95% confidence interval, CI: 71.6-100%), specificity 98% (95% CI: 86.7-99.9%), positive predictive value (PPV) 92.9% (95% CI: 64.2-99.6%), and negative predictive value 100% (95% CI: 89.9-100%). CONCLUSION: In paediatric CAD, adenosine stress perfusion CMR imaging is adequate as an initial, non-invasive screening test for the identification of significant coronary artery lesions, with anatomical imaging used to confirm the extent of the culprit lesion.


Assuntos
Adenosina , Angiografia por Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Intensificação de Imagem Radiográfica , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Intervalos de Confiança , Angiografia Coronária/métodos , Circulação Coronária/fisiologia , Teste de Esforço , Feminino , Humanos , Masculino , Imagem de Perfusão do Miocárdio/métodos , Pediatria , Valor Preditivo dos Testes , Estudos Retrospectivos
10.
Cardiovasc Eng Technol ; 8(1): 17-29, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27873180

RESUMO

Surgical aortic valve replacement is the most common procedure of choice for the treatment of severe aortic stenosis. Bioprosthetic valves are traditionally sewed-in the aortic root by means of pledget-armed sutures during open-heart surgery. Recently, novel bioprostheses which include a stent-based anchoring system have been introduced to allow rapid implantation, therefore reducing the duration and invasiveness of the intervention. Different effects on the hemodynamics were clinically reported associated with the two technologies. The aim of this study was therefore to investigate whether the differences in hemodynamic performances are an effect of different anchoring systems. Two commercially available bio-prosthetic aortic valves, one sewed-in with pledget-armed sutures and one rapid-deployment, were thus tested in this study by means of a combined approach of experimental and computational tools. In vitro experiments were performed to evaluate the overall hydrodynamic performance under identical standard conditions; computational fluid dynamics analyses were set-up to explore local flow variations due to different design of the anchoring system. The results showed how the performance of cardiac valve substitutes is negatively affected by the presence of pledget-armed sutures. These are causing flow disturbances, which in turn increase the mean pressure gradient and decrease the effective orifice area. The combined approach of experiments and numerical simulations can be effectively used to quantify the detailed relationship between local fluid-dynamics and overall performances associated with different valve technologies.


Assuntos
Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Modelos Cardiovasculares , Suturas/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Hemodinâmica , Humanos
11.
Ann Thorac Surg ; 103(2): 645-654, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27592606

RESUMO

BACKGROUND: Aortic arch reconstruction after hypoplastic left heart syndrome (HLHS) palliation can vary widely in shape and dimensions between patients. Arch morphology alone may affect cardiac function and outcome. We sought to uncover the relationship of arch three-dimensional shape features with functional and short-term outcome data after total cavopulmonary connection (TCPC). METHODS: Aortic arch shape models of 37 patients with HLHS (age, 2.89 ± 0.99 years) were reconstructed from magnetic resonance data before TCPC completion. A novel, validated statistical shape analysis method was used to compute a three-dimensional anatomic mean shape from the cohort and calculate the deformation vectors of the mean shape toward each patient's specific anatomy. From these deformations, three-dimensional shape features most related to ventricular ejection fraction, indexed end-diastolic volume, and superior cavopulmonary pressure were extracted by partial least-square regression analysis. Shape patterns relating to intensive care unit and hospital lengths of stay after TCPC were assessed. RESULTS: Distinct deformation patterns, which result in an acutely mismatched aortic root and ascending aorta, and a gothic-like transverse arch, correlated with increased indexed end-diastolic volume and higher superior cavopulmonary pressure but not with ejection fraction. Specific arch morphology with pronounced transverse arch and descending aorta mismatch also correlated with longer intensive care unit and hospital lengths of stay after TCPC completion. CONCLUSIONS: Independent of hemodynamically important arch obstruction, altered aortic morphology in HLHS patients appears to have important associations with higher superior cavopulmonary pressure and with short-term outcomes after TCPC completion as highlighted by statistical shape analysis, which could act as adjunct to risk assessment in HLHS.


Assuntos
Aorta Torácica/diagnóstico por imagem , Técnica de Fontan/métodos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Imagem Cinética por Ressonância Magnética/métodos , Cuidados Paliativos/métodos , Volume Sistólico/fisiologia , Aorta Torácica/cirurgia , Pré-Escolar , Feminino , Seguimentos , Humanos , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico , Síndrome do Coração Esquerdo Hipoplásico/fisiopatologia , Imageamento Tridimensional , Masculino , Estudos Retrospectivos , Resultado do Tratamento
12.
J Thorac Cardiovasc Surg ; 153(2): 418-427, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27776913

RESUMO

OBJECTIVES: Even after successful aortic coarctation repair, there remains a significant incidence of late systemic hypertension and other morbidities. Independently of residual obstruction, aortic arch morphology alone may affect cardiac function and outcome. We sought to uncover the relationship of arch 3-dimensional shape features with functional data obtained from cardiac magnetic resonance scans. METHODS: Three-dimensional aortic arch shape models of 53 patients (mean age, 22.3 ± 5.6 years) 12 to 38 years after aortic coarctation repair were reconstructed from cardiac magnetic resonance data. A novel validated statistical shape analysis method computed a 3-dimensional mean anatomic shape of all aortic arches and calculated deformation vectors of the mean shape toward each patient's arch anatomy. From these deformations, 3-dimensional shape features most related to left ventricular ejection fraction, indexed left ventricular end-diastolic volume, indexed left ventricular mass, and resting systolic blood pressure were extracted from the deformation vectors via partial least-squares regression. RESULTS: Distinct arch shape features correlated significantly with left ventricular ejection fraction (r = 0.42, P = .024), indexed left ventricular end-diastolic volume (r = 0.65, P < .001), and indexed left ventricular mass (r = 0.44, P = .014). Lower left ventricular ejection fraction, larger indexed left ventricular end-diastolic volume, and increased indexed left ventricular mass were identified with an aortic arch shape that has an elongated ascending aorta with a high arch height-to-width ratio, a relatively short proximal transverse arch, and a relatively dilated descending aorta. High blood pressure seemed to be linked to gothic arch shape features, but this did not achieve statistical significance. CONCLUSIONS: Independently of hemodynamically important arch obstruction or residual aortic coarctation, specific aortic arch shape features late after successful aortic coarctation repair seem to be associated with worse left ventricular function. Analyzing 3-dimensional shape information via statistical shape modeling can be an adjunct to long-term risk assessment in patients after aortic coarctation repair.


Assuntos
Aorta Torácica/diagnóstico por imagem , Coartação Aórtica/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Volume Sistólico/fisiologia , Procedimentos Cirúrgicos Vasculares/métodos , Função Ventricular Esquerda/fisiologia , Adolescente , Adulto , Aorta Torácica/cirurgia , Coartação Aórtica/diagnóstico , Criança , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Imageamento Tridimensional , Masculino , Resultado do Tratamento , Adulto Jovem
13.
Eur J Cardiothorac Surg ; 48(5): 716-23, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25661076

RESUMO

OBJECTIVES: Twenty years ago our institution published an analysis of a cluster of failures associated with the arterial switch operation (ASO). The concept of 'near miss' was explored to detect warning signs of suboptimal performance. The aim of the current study was to review the parameters best suited to monitoring early ASO outcomes in the modern setting and re-examine the concept of near misses as failure equivalents. METHODS: All ASOs performed in our institution between 1983 and 2012 were reviewed. The experience was divided into three eras (1983-92, 1993-2002 and 2003-12). The cumulative sum graphic for sequential monitoring was used for early mortality. The need to re-establish cardiopulmonary bypass (CPB), CPB time >240 min and extracorporeal membrane oxygenation (ECMO) were explored as variables of near misses. RESULTS: The cohort consisted of 606 patients. The 30-day mortality rate was 23% (n = 29) in Era 1, 6% (n = 14) in Era 2 and 1% (n = 3) in Era 3. There were further 4, 8 and 6 deaths between 30 and 90 days in the three eras, respectively. In Era 3, the majority of deaths occurred between 30 and 90 days. In the current era, ECMO and CPB time >240 min as a marker of near miss was associated with an increased risk of death both within 30 days and 90 days after ASO. CONCLUSIONS: The 30-day outcomes of ASO have significantly improved over the last 30 years. As life-saving mechanical support after surgery has been implemented more often, an extended 90-day window of reporting can offer a more realistic outcome indicator of performance.


Assuntos
Transposição das Grandes Artérias/efeitos adversos , Transposição das Grandes Artérias/mortalidade , Transposição dos Grandes Vasos/mortalidade , Transposição dos Grandes Vasos/cirurgia , Transposição das Grandes Artérias/normas , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Transposição dos Grandes Vasos/epidemiologia , Resultado do Tratamento
14.
J Am Soc Echocardiogr ; 28(3): 363-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25499839

RESUMO

BACKGROUND: The right ventricle is a complex structure that is challenging to quantify by two-dimensional (2D) echocardiography. Unlike disk summation three-dimensional (3D) echocardiography (3DE), single-beat 3DE can acquire large volumes at high volume rates in one cardiac cycle, avoiding stitching artifacts or long breath-holds. The aim of this study was to assess the accuracy and test-retest reproducibility of single-beat 3DE for quantifying right ventricular (RV) volumes in adult populations of acquired RV pressure or volume overload, namely, pulmonary hypertension (PH) and carcinoid heart disease, respectively. Three-dimensional and 2D echocardiographic indices were also compared for identifying RV dysfunction in PH. METHODS: A prospective cross-sectional study was performed in 100 individuals who underwent 2D echocardiography, 3DE, and cardiac magnetic resonance imaging: 49 patients with PH, 20 with carcinoid heart disease, 11 with metastatic carcinoid tumors without cardiac involvement, and 20 healthy volunteers. Two operators performed test-retest acquisition and postprocessing for inter- and intraobserver reproducibility in 20 subjects. RESULTS: RV single-beat 3DE was attainable in 96% of cases, with mean volume rates of 32 to 45 volumes/sec. Bland-Altman analysis of all subjects (presented as mean bias ± 95% limits of agreement) revealed good agreement for end-diastolic volume (-2.3 ± 27.4 mL) and end-systolic volume (5.2 ± 19.0 mL) measured by 3DE and cardiac magnetic resonance imaging, with a tendency to underestimate stroke volume (-7.5 ± 23.6 mL) and ejection fraction (-4.6 ± 13.8%) by 3DE. Subgroup analysis demonstrated a greater bias for volumetric underestimation, particularly in healthy volunteers (end-diastolic volume, -11.9 ± 18.0 mL; stroke volume, -11.2 ± 20.2 mL). Receiver operating characteristic curve analysis showed that 3DE-derived ejection fraction was significantly superior to 2D echocardiographic parameters for identifying RV dysfunction in PH (sensitivity, 94%; specificity, 88%; area under the curve, 0.95; P = .031). There was significant interobserver test-retest bias for RV volume underestimation (end-diastolic volume, -12.5 ± 28.1 mL; stroke volume, -10.6 ± 23.2 mL). CONCLUSIONS: Single-beat 3DE is feasible and clinically applicable for volumetric quantification in acquired RV pressure or volume overload. It has improved limits of agreement compared with previous disk summation 3D echocardiographic studies and has incremental value over standard 2D echocardiographic measures for identifying RV dysfunction. Despite the ability to obtain and postprocess a full-volume 3D echocardiographic RV data set, the quality of the raw data did influence the accuracy of the data obtained. The technique performs better with dilated rather than nondilated RV cavities, with a learning curve that might affect the test-retest reproducibility for serial RV studies.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Ecocardiografia Tridimensional/métodos , Interpretação de Imagem Assistida por Computador/métodos , Volume Sistólico , Disfunção Ventricular Direita/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
J Thorac Cardiovasc Surg ; 148(6): 2627-33, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25224549

RESUMO

OBJECTIVE: The aim of this study was to compare atrial switch and arterial switch operations for the repair of transposition of the great arteries (TGA), assessing cardiac function and ventriculoarterial (VA) coupling based on cardiac magnetic resonance (CMR) data. Using CMR-derived wave intensity analysis, this study provides a noninvasive comparison of the 2 systemic ventricles and evaluates the subclinical hemodynamic burden of these operations. METHODS: Fifty-four patients (18 controls, 18 atrial switches, 18 arterial switches) were studied. Dimensional and functional data, including the ejection fraction (EF) and end-diastolic volume, were derived from CMR, as well as aortic distensibility. Wave intensity was computed from CMR according to a formulation based on changes in area and velocity, and the peaks of the 2 major systolic waves (forward compression wave [FCW], and forward expansion wave [FEW]) were measured as indicators of ventricular function. RESULTS: Both switches exhibited significantly increased end-diastolic volume and enlarged aortic root areas, and atrial switches were also characterized by significantly lower EF. Patients with TGA presented stiffer ascending aortas, particularly those repaired with an arterial switch. Both FCW and FEW were significantly lower in both TGA cohorts than the controls, suggesting compromised VA coupling, likely a result of increased impedance caused by the stiffer ascending aorta. A significant difference between switch type was noticed in terms of the FEW peak, which was lower in the atrial switch group. CONCLUSIONS: These data highlight reduced aortic distensibility and abnormal VA coupling in repaired TGA. An intraoperational difference was noted in terms of EF and peak FEW, likely reflecting the different nature of the subaortic ventricle.


Assuntos
Aorta/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Átrios do Coração/cirurgia , Transposição dos Grandes Vasos/cirurgia , Função Ventricular , Adolescente , Adulto , Aorta/fisiopatologia , Pressão Arterial , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Estudos Transversais , Feminino , Átrios do Coração/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Cuidados Paliativos , Estudos Retrospectivos , Volume Sistólico , Transposição dos Grandes Vasos/diagnóstico , Transposição dos Grandes Vasos/fisiopatologia , Resultado do Tratamento , Rigidez Vascular , Adulto Jovem
16.
Ann Thorac Surg ; 98(2): 648-54, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24906601

RESUMO

BACKGROUND: The size of the modified Blalock-Taussig shunt and the additional presence of aortic coarctation can affect the hemodynamics of the Norwood physiology. Multiscale modeling was used to gather insight into the effects of these variables, in particular on coronary perfusion. METHODS: A model was reconstructed from cardiac magnetic resonance imaging data of a representative patient, and then simplified with computer-aided design software. Changes were systematically imposed to the semi-idealized three-dimensional model, resulting in a family of nine models (3-, 3.5-, and 4-mm shunt diameter; 0%, 60%, and 90% coarctation severity). Each model was coupled to a lumped parameter network representing the remainder of the circulation to run multiscale simulations. Simulations were repeated including the effect of preserved cerebral perfusion. RESULTS: The concomitant presence of a large shunt and tight coarctation was detrimental in terms of coronary perfusion (13.4% maximal reduction, 1.07 versus 0.927 mL/s) and oxygen delivery (29% maximum reduction, 422 versus 300 mL·min(-1)·m(-2)). A variation in the ratio of pulmonary to systemic blood flow from 0.9 to 1.6 also indicated a "stealing" phenomenon to the detriment of the coronary circulation. A difference could be further appreciated in the computational ventricular pressure-volume loops, with augmented systolic pressures and decreased stroke volumes for tighter coarctation. Accounting for constant cerebral perfusion did not produce substantially different results. CONCLUSIONS: Multiscale simulations performed in a parametric fashion revealed a reduction in coronary perfusion in the presence of a large modified Blalock-Taussig shunt and severe coarctation in Norwood patients.


Assuntos
Coartação Aórtica , Procedimento de Blalock-Taussig/métodos , Circulação Coronária , Imageamento Tridimensional , Modelos Cardiovasculares , Procedimentos de Norwood , Coartação Aórtica/fisiopatologia , Humanos , Índice de Gravidade de Doença
17.
J Thorac Cardiovasc Surg ; 148(4): 1526-33, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24629219

RESUMO

OBJECTIVE: To assess the coupling efficiency in hypoplastic left heart syndrome, considering the effect of surgical arch reconstruction and the shunt type received during the Norwood procedure. METHODS: Ventriculoarterial coupling was assessed before Fontan completion in 32 patients with hypoplastic left heart syndrome (19 modified Blalock-Taussig and 13 Sano shunts at stage 1). Cardiovascular magnetic resonance data were analyzed, deriving functional parameters and 3-dimensional volumes. Dimensional indexes were computed from 3-dimensional data sets as the area ratio of the isthmus to the descending aorta (Risthmus) and the isthmus to surgically enlarged transverse arch (Rarch). Wave intensity was calculated from cardiac magnetic resonance, using the peaks of the forward compression and expansion waves in early and late systole as surrogate indicators of ventriculoarterial coupling. RESULTS: Aortic distensibility (3.6±2.7×10(-3) 1/mm Hg) was not associated with the time elapsed from stage 1 palliation (P=.94), suggesting an early loss of elasticity that did not progress thereafter. Risthmus was 1.0±0.4, and Rarch was 0.3±0.1, indicating the dilated reconstructed arch was the main anatomic feature. The forward compression wave correlated significantly with Rarch (R2=0.23, P=.006) but not with Risthmus (R2<0.01, P=.63). Patients with a reduced ejection fraction exhibited a larger ventricular mass (R2=0.28, P=.003). The Sano shunt patients had a lower ejection fraction (51%±6% vs 57%±6%, P=.02); however, neither the forward compression nor expansion wave varied significantly between shunt type or the other functional parameters. CONCLUSIONS: Ventriculoarterial coupling in operated hypoplastic left heart syndrome was affected by aortic arch size mismatch but not by the type of shunt placed at the Norwood operation.


Assuntos
Técnica de Fontan , Síndrome do Coração Esquerdo Hipoplásico/fisiopatologia , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Procedimentos de Norwood , Pré-Escolar , Elasticidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Cuidados Paliativos , Análise de Onda de Pulso , Estudos Retrospectivos , Resultado do Tratamento , Rigidez Vascular
18.
J Bone Joint Surg Am ; 95(19): 1737-44, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24088965

RESUMO

BACKGROUND: The aim of this study was to compare the outcomes of displaced distal radial fractures treated with a volar locking plate with the results of such fractures treated with a conventional method of closed reduction and percutaneous wire fixation with supplemental bridging external fixation when required. Our aim was to ascertain whether the use of a volar locking plate improves functional outcomes. METHODS: A single-center, pragmatic, randomized controlled trial was conducted in a tertiary care institution. One hundred and thirty patients (eighteen to seventy-three years of age) who had a displaced distal radial fracture were randomized to treatment with either a volar locking plate (n = 66) or a conventional percutaneous fixation method (n = 64). Outcome assessments were conducted at six weeks, twelve weeks, and one year. Outcomes were measured on the basis of scores on the Patient Evaluation Measure (PEM) and QuickDASH questionnaire (a shortened version of the Disabilities of the Arm, Shoulder and Hand, or DASH, Outcome Measure), EuroQol-5D (EQ-5D) scores, wrist range of motion, grip strength, and radiographic parameters. RESULTS: The rate of follow-up at one year was 95%. Patients in the volar locking-plate group had significantly better PEM and QuickDASH scores and range of motion at six weeks compared with patients in the conventional-treatment group, but there were no significant differences between the two groups at twelve weeks or one year. Grip strength was better in the plate group at all time points. The volar locking plate was better at restoring palmar tilt and radial height. Significantly more patients in the plate group were driving at the end of six weeks, but this did not translate to a significant difference between groups in terms of those returning to work by that time. CONCLUSIONS: Use of a volar locking plate resulted in a faster early recovery of function compared with use of conventional methods. However, no functional advantage was demonstrated at or beyond twelve weeks. Use of the volar locking plate resulted in better anatomical reduction and grip strength, but there was no significant difference in function between the groups at twelve weeks or one year. The earlier recovery of function may be of advantage to some patients. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas do Rádio/cirurgia , Adolescente , Adulto , Idoso , Remoção de Dispositivo/estatística & dados numéricos , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Complicações Pós-Operatórias/etiologia , Qualidade de Vida , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Reoperação/estatística & dados numéricos , Resultado do Tratamento , Adulto Jovem
19.
Stress ; 16(4): 369-76, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23425242

RESUMO

In contrast to heavy alcohol consumption, which is harmful, light to moderate drinking has been linked to reduced cardiovascular morbidity and mortality. Effects on lipid status or clotting do not fully explain these benefits. Exaggerated cardiovascular responses to mental stress are detrimental to cardiovascular health. We hypothesized that habitual alcohol consumption might reduce these responses, with potential benefits. Advanced magnetic resonance techniques were used to accurately measure cardiovascular responses to an acute mental stressor (Montreal Imaging Stress Task) in 88 healthy adults (∼1:1 male:female). Salivary cortisol and task performance measures were used to assess endocrine and cognitive responses. Habitual alcohol consumption and confounding factors were assessed by questionnaire. Alcohol consumption was inversely related to responses of heart rate (HR) (r = -0.31, p = 0.01), cardiac output (CO) (r = -0.32, p = 0.01), vascular resistance (r = 0.25, p = 0.04) and mean blood pressure (r = -0.31, p = 0.01) provoked by stress, but not to stroke volume (SV), or arterial compliance changes. However, high alcohol consumers had greater cortisol stress responses, compared to moderate consumers (3.5 versus 0.7 nmol/L, p = 0.04). Cognitive measures did not differ. Findings were not explained by variations in age, sex, social class, ethnicity, physical activity, adrenocortical activity, adiposity, smoking, menstrual phase and chronic stress. Habitual alcohol consumption is associated with reduced cardiac responsiveness during mental stress, which has been linked to lower risk of hypertension and vascular disease. Consistent with established evidence, our findings suggest a mechanism by which moderate alcohol consumption might reduce cardiovascular disease, but not high consumption, where effects such as greater cortisol stress responses may negate any benefits.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Estresse Psicológico/fisiopatologia , Adulto , Débito Cardíaco , Doenças Cardiovasculares , Sistema Cardiovascular/efeitos dos fármacos , Cognição , Etanol/farmacologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Saliva/química
20.
Eur Heart J Cardiovasc Imaging ; 14(10): 963-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23389732

RESUMO

AIMS: After atrial redirection surgery (Mustard-Senning operations) for transposition of the great arteries (TGA), the systemic right ventricle (RV) suffers from late systolic failure with high morbidity and mortality. Mechanisms of late RV failure are poorly characterized. We hypothesized that diffuse interstitial expansion representing diffuse fibrosis is greater in systemic RVs of patients following Mustard-Senning surgery and that it would be associated with other markers of heart failure and disease severity. METHODS AND RESULTS: We used equilibrium contrast cardiovascular magnetic resonance (CMR) imaging to quantify extracellular volume (ECV) in the septum and RV free wall of 14 adults presenting to a specialist clinic late after surgery for TGA (8 Mustard, 6 female, median age 33). These were compared with 14 age-and sex-matched healthy volunteers. Patients were assessed with a standardized CMR protocol, NT-brain natriuretic peptide (NT-proBNP), and cardiopulmonary exercise (CPEX) testing. The mean septal ECV was significantly higher in patients than controls (0.254 ± 0.036 vs. 0.230 ± 0.032; P = 0.03). NT-proBNP positively related to septal ECV (P = 0.04; r = 0.55). The chronotropic index (CI) during CPEX testing negatively related to the ECV (P = 0.04; r = -0.58). No relationship was seen with other CMR or CPEX parameters. R.V free wall ECV was difficult to measure (heavy trabeculation, sternal wires, blood pool in regions of interest) with high and poor inter-observer reproducibility: this analysis was abandoned. CONCLUSION: Septal interstitial expansion is seen in adults late after atrial redirection surgery for TGA. It correlates well with NT-proBNP and CI and may have a role in the development of RV systolic impairment. Measuring interstitial expansion in the RV free wall is difficult using this methodology.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cardiomiopatias/patologia , Ventrículos do Coração/patologia , Imagem Cinética por Ressonância Magnética , Transposição dos Grandes Vasos/cirurgia , Adulto , Análise de Variância , Procedimentos Cirúrgicos Cardíacos/métodos , Cardiomiopatias/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Meios de Contraste , Teste de Esforço , Feminino , Fibrose/patologia , Seguimentos , Gadolínio , Humanos , Aumento da Imagem , Masculino , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Valores de Referência , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Transposição dos Grandes Vasos/diagnóstico , Ultrassonografia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia
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