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Background The recent release of large language models (LLMs) for public use, such as ChatGPT and Google Bard, has opened up a multitude of potential benefits as well as challenges. Purpose To evaluate and compare the accuracy and consistency of responses generated by publicly available ChatGPT-3.5 and Google Bard to non-expert questions related to lung cancer prevention, screening, and terminology commonly used in radiology reports based on the recommendation of Lung Imaging Reporting and Data System (Lung-RADS) v2022 from American College of Radiology and Fleischner society. Materials and Methods Forty of the exact same questions were created and presented to ChatGPT-3.5 and Google Bard experimental version as well as Bing and Google search engines by three different authors of this paper. Each answer was reviewed by two radiologists for accuracy. Responses were scored as correct, partially correct, incorrect, or unanswered. Consistency was also evaluated among the answers. Here, consistency was defined as the agreement between the three answers provided by ChatGPT-3.5, Google Bard experimental version, Bing, and Google search engines regardless of whether the concept conveyed was correct or incorrect. The accuracy among different tools were evaluated using Stata. Results ChatGPT-3.5 answered 120 questions with 85 (70.8%) correct, 14 (11.7%) partially correct, and 21 (17.5%) incorrect. Google Bard did not answer 23 (19.1%) questions. Among the 97 questions answered by Google Bard, 62 (51.7%) were correct, 11 (9.2%) were partially correct, and 24 (20%) were incorrect. Bing answered 120 questions with 74 (61.7%) correct, 13 (10.8%) partially correct, and 33 (27.5%) incorrect. Google search engine answered 120 questions with 66 (55%) correct, 27 (22.5%) partially correct, and 27 (22.5%) incorrect. The ChatGPT-3.5 is more likely to provide correct or partially answer than Google Bard, approximately by 1.5 folds (OR = 1.55, P = 0.004). ChatGPT-3.5 and Google search engine were more likely to be consistent than Google Bard by approximately 7 and 29 folds (OR = 6.65, P = 0.002 for ChatGPT and OR = 28.83, P = 0.002 for Google search engine, respectively). Conclusion Although ChatGPT-3.5 had a higher accuracy in comparison with the other tools, neither ChatGPT nor Google Bard, Bing and Google search engines answered all questions correctly and with 100% consistency.
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Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Ferramenta de Busca , Tomografia Computadorizada por Raios X , Idioma , Inteligência ArtificialRESUMO
PURPOSE: To evaluate the safety of MRI in patients with fragmented retained leads (FRLs) through numerical simulation and phantom experiments. METHODS: Electromagnetic and thermal simulations were performed to determine the worst-case RF heating of 10 patient-derived FRL models during MRI at 1.5 T and 3 T and at imaging landmarks corresponding to head, chest, and abdomen. RF heating measurements were performed in phantoms implanted with reconstructed FRL models that produced highest heating in numerical simulations. The potential for unintended tissue stimulation was assessed through a conservative estimation of the electric field induced in the tissue due to gradient-induced voltages developed along the length of FRLs. RESULTS: In simulations under conservative approach, RF exposure at B1+ ≤ 2 µT generated cumulative equivalent minutes (CEM)43 < 40 at all imaging landmarks at both 1.5 T and 3 T, indicating no thermal damage for acquisition times (TAs) < 10 min. In experiments, the maximum temperature rise when FRLs were positioned at the location of maximum electric field exposure was measured to be 2.4°C at 3 T and 2.1°C at 1.5 T. Electric fields induced in the tissue due to gradient-induced voltages remained below the threshold for cardiac tissue stimulation in all cases. CONCLUSIONS: Simulation and experimental results indicate that patients with FRLs can be scanned safely at both 1.5 T and 3 T with most clinical pulse sequences.
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Imageamento por Ressonância Magnética , Ondas de Rádio , Coração/diagnóstico por imagem , Calefação , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Imagens de FantasmasRESUMO
Transluminal attenuation gradient (TAG), defined as the gradient of the contrast agent attenuation drop along the vessel, is an imaging biomarker that indicates stenosis in the coronary arteries. The transluminal attenuation flow encoding (TAFE) equation is a theoretical platform that quantifies blood flow in each coronary artery based on computed tomography angiography (CTA) imaging. This formulation couples TAG (i.e., contrast dispersion along the vessel) with fluid dynamics. However, this theoretical concept has never been validated experimentally. The aim of this proof-of-principle phantom study is to validate TAFE based on CTA imaging. Dynamic CTA images were acquired every 0.5 s. The average TAFE estimated flow rates were compared against four predefined pump values in a straight (20, 25, 30, 35, and 40 ml/min) and a tapered phantom (25, 35, 45, and 55 ml/min). Using the TAFE formulation with no correction, the flow rates were underestimated by 33% and 81% in the straight and tapered phantoms, respectively. The TAFE formulation was corrected for imaging artifacts focusing on partial volume averaging and radial variation of contrast enhancement. After corrections, the flow rates estimated in the straight and tapered phantoms had an excellent Pearson correlation of r = 0.99 and 0.87 (p < 0.001), respectively, with only a 0.6%±0.2 mL/min difference in estimation of the flow rate. In this proof-of-concept phantom study, we corrected the TAFE formulation and showed a good agreement with the actual pump values. Future clinical validations are needed for feasibility of TAFE in clinical use.
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Angiografia por Tomografia Computadorizada , Vasos Coronários , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Imagens de Fantasmas , Tomografia Computadorizada por Raios XRESUMO
Coronary artery bypass grafting (CABG) surgery with two methods (on-pump or off-pump) can be used to rescue individuals with severe coronary artery disease (CAD). Each method might cause an inflammatory response, which can lead to some complications. The aim of this study was to compare the changes in serum concentrations of IFN-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, VEGF, MCP-1, and epidermal growth factor between the two CABG surgery methods. Forty-eight patients (22 = on-pump, 26 = off-pump) who underwent on-pump or off-pump CABG surgery were enrolled in this study. Serum cytokines levels were measured in two blood samples, the first sample was taken from each patient in the morning of the day of surgery after a 12-hr fasting and the second sample on the first postoperative day at 24-hr after surgery. In baseline, comparisons between the two groups of on-pump/off-pump surgery did not show any significant difference in demographic data, anthropometric parameters, lipid profile indices, and high-sensitivity C-reactive protein levels (p > .05). There was a significant difference between the serum levels of IL-4, IL-6, IL-10, vascular endothelial growth factor (VEGF), IFN-γ, and MCP-1 in patients with on-pump surgery and a significant increase in serum IL-6 (p < .001), IL8 (p < .05), VEGF (p < .001), and IFN-γ (p < .01) levels in patients with off-pump surgery in post-operation stage compared to pre-operation. Cardiopulmonary pump in patients under CABG surgery can activate systemic inflammation and the changes of serum cytokines levels in off-pump CABG were lower compared with on-pump CABG.
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Ponte de Artéria Coronária sem Circulação Extracorpórea , Citocinas , Quimiocinas , Ponte de Artéria Coronária/métodos , Humanos , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
Background The risks associated with MRI in individuals who have implanted cardiac devices are thought to arise from the interaction between the implanted device and static, gradient, and radiofrequency magnetic fields. Purpose To determine the relationship between the peak whole-body averaged specific absorption rate (SAR) and change in magnetic field per unit time (dB/dt), maximum specific energy dose, imaging region, and implanted cardiac device characteristics and their function in patients undergoing MRI. Materials and Methods This prospective observational cohort study was conducted from October 16, 2003, to January 22, 2015 (https://ClinicalTrials.gov, NCT01130896). Any individual with an implanted cardiac device who was referred for MRI was included. Clinical MRI protocols without SAR restriction were used. Exclusion criteria were newly implanted leads, abandoned or epicardial leads, and dependence on a pacemaker with an implantable cardioverter defibrillator without asynchronous pacing capability. For each MRI pulse sequence, the calculated whole-body values for SAR, dB/dt, and scan duration were collected. Atrial and ventricular sensing, lead impedance, and capture threshold were evaluated before and immediately after (within 10 minutes) completion of each MRI examination. Generalized estimating equations with Gaussian family, identity link, and an exchangeable working correlation matrix were used for statistical analysis. Results A total of 2028 MRI examinations were performed in 1464 study participants with 2755 device leads (mean age, 67 years ± 15 [standard deviation]; 930 men [64%]). There was no evidence of an association between radiofrequency energy deposition, dB/dt, or scan duration and changes in device parameters. Thoracic MRI was associated with decreased battery voltage immediately after MRI (ß = -0.008 V, P < .001). Additionally, right ventricular (RV) lead length was associated with decreased RV sensing (ß = -0.012 mV, P = .05) and reduced RV capture threshold (ß = -0.002 V, P < .01) immediately after MRI. Conclusion There was no evidence of an association between MRI parameters that characterize patient exposure to radiofrequency energy and changes in device and lead parameters immediately after MRI. Nevertheless, device interrogation before and after MRI remains mandatory due to the potential for device reset and changes in lead or generator parameters. © RSNA, 2020 See also the editorial by Shellock in this issue.
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Desfibriladores Implantáveis , Imageamento por Ressonância Magnética/métodos , Marca-Passo Artificial , Segurança do Paciente , Idoso , Protocolos Clínicos , Segurança de Equipamentos , Feminino , Humanos , Masculino , Estudos Prospectivos , Ondas de RádioRESUMO
BACKGROUND: The effect of different expressions of aortic valve disease on 3D aortic hemodynamics is unclear. PURPOSE: To investigate changes in aortic hemodynamics in patients with dilated ascending aorta (AAo) but different severity of aortic valve stenosis (AS) and/or regurgitation (AR). STUDY TYPE: Retrospective. POPULATION: A total of 111 subjects (86 patients with AAo diameter ≥ 40 mm and 25 healthy controls, all with trileaflet aortic valve [TAV]). Patients were further stratified by TAV dysfunction: n = 9 with combined moderate or severe AS and AR (ASR, 56 ± 13 years), n = 14 with moderate or severe AS (AS, 64 ± 14 years), n = 33 with moderate or severe AR (AR, 62 ± 14 years), n = 30 with neither AS nor AR (no AS/AR, 63 ± 9 years). FIELD STRENGTH/SEQUENCE: 4D flow MRI on 1.5/3T systems for the in vivo analysis of aortic blood flow dynamics. ASSESSMENT: Data analysis included grading of 3D AAo vortex/helix flow and AAo flow eccentricity as well as quantification of systolic peak velocities and wall shear stress (WSS). STATISTICAL TESTS: Continuous variables were compared by one-way analysis of variance or Kruskal-Wallis, followed by a pairwise Tukey or Dunn test if there was a significant difference. RESULTS: All patients demonstrated markedly elevated vortex and helix flow compared with controls (P < 0.05). Peak velocities were significantly elevated in ASR, AS, and AR patients compared with controls (P < 0.05). Increased flow eccentricity was observed in entire AAo for AR, at the mid and distal AAo for ASR and AS, and at the proximal AAo for no AS/AR. Compared with controls, WSS in the AAo was significantly elevated in ASR and AS patients (P < 0.05) and reduced in no AS/AR patients (P < 0.05). DATA CONCLUSION: The presence of TAV dysfunction is associated with aberrant hemodynamics and altered WSS, which may play a role in the development of aortopathy. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:481-491.
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Valvopatia Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Valva Aórtica/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Dilatação , Hemodinâmica , Humanos , Estudos RetrospectivosRESUMO
PURPOSE: To evaluate the local specific absorption rate (SAR) and heating around retained cardiac leads during MRI at 64 MHz (1.5T) and 127 MHz (3T) as a function of RF coil type and imaging landmark. METHODS: Numerical models of retained cardiac leads were built from CT and X-ray images of 6 patients with retained cardiac leads. Electromagnetic simulations and bio-heat modeling were performed with MRI RF body and head coils tuned to 64 MHz and 127 MHz and positioned at 9 different imaging landmarks covering an area from the head to the lower limbs. RESULTS: For all patients and at both 1.5T and 3T, local transmit head coils produced negligible temperature rise ( Δ T < 0.1 ° C ) for â â B 1 + â â ≤ 3 µ T . For body imaging with quadrature-driven coils at 1.5T, Δ T during a 10-min scan remained < 3°C at all imaging landmarks for â â B 1 + â â ≤ 3 µ T and <6°C for â â B 1 + â â ≤ 4 µ T . For body imaging at 3T, Δ T during a 10-min scan remained < 6°C at all imaging landmarks for â â B 1 + â â ≤ 2 µ T . For shorter pulse sequences up to 2 min, Δ T remained < 6°C for â â B 1 + â â ≤ 3 µ T . CONCLUSION: For the models based on 6 patients studied, simulations suggest that MRI could be performed safely using a local head coil at both 1.5T and 3T, and with a body coil at 1.5T with pulses that produced â â B 1 + â â ≤ 4 µ T . MRI at 3T could be performed safely in these patients using pulses with â â B 1 + â â ≤ 2 µ T .
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Desfibriladores Implantáveis/efeitos adversos , Remoção de Dispositivo , Corpos Estranhos , Insuficiência Cardíaca/cirurgia , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ondas de Rádio , Adulto , Algoritmos , Simulação por Computador , Feminino , Análise de Elementos Finitos , Frequência Cardíaca , Transplante de Coração , Temperatura Alta , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Perna (Membro)/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial/efeitos adversos , Segurança do Paciente , Complicações Pós-Operatórias/cirurgia , Próteses e Implantes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto JovemRESUMO
PURPOSE: Late gadolinium enhancement cardiac MR (LGE-CMR) and extracellular volume fraction (ECV-CMR) are widely used to evaluate macroscopic and microscopic myocardial fibrosis. Macrocyclic contrast media are increasingly used off-label for myocardial scar assessment, given the superior safety profile of these agents. We aimed to assess the performance of two macrocyclic contrast agents, gadoterate meglumine and gadobutrol, for the evaluation of myocardial scar. MATERIAL AND METHODS: Forty subjects (61 ± 11 years, 67.5% men) who underwent LGE-CMR using gadobutrol were prospectively recruited for a research CMR scan using same-dose gadoterate meglumine (0.2 mmol/kg) at 1.5 T. Myocardial scar quantification was performed using a short-axis phase-sensitive inversion recovery (PSIR) Turbo-FLASH and steady-state free precession (SSFP) images. Pre- and post-contrast T1-mapping was employed to assess myocardial ECV. An intraclass correlation coefficient (ICC) was used to check for reliability between the two contrast agents. RESULTS: Using manual thresholding on PSIR Turbo-FLASH images, mean LGE scar percentage (LGE%) was 9.9 ± 9.7% and 9.4 ± 9.7% for gadobutrol and gadoterate meglumine, respectively (p > 0.05) (ICC: 0.99, 95% CI: 0.97-0.99). Using the PSIR SSFP technique and manual thresholding, LGE% averaged 7.5 ± 9.0% and 7.1 ± 8.6% for gadobutrol and gadoterate meglumine, respectively (p > 0.05) (ICC: 0.99, 95% CI: 0.98-0.99). Average ECV with gadobutrol and gadoterate meglumine were similar at 28.40 ± 4.88 and 28.46 ± 4.73 (p > 0.05) with a strong correlation (ICC: 0.98, 95% CI: 0.94-0.99). CONCLUSION: We found LGE- and ECV-CMR values derived from gadoterate meglumine comparable to values derived from gadobutrol. Gadoterate meglumine has a comparable performance to gadobutrol in identifying LGE-derived myocardial scar both qualitatively and quantitatively. KEY POINTS: ⢠Late gadolinium-enhancement cardiac MR (LGE-MR) and extracellular volume (ECV) fraction are widely used to evaluate macroscopic and microscopic myocardial fibrosis. ⢠Macrocyclic contrast media are increasingly used off-label for myocardial scar assessment, given the presumed superior safety profile of these agents. ⢠LGE- and ECV-CMR values derived from gadoterate meglumine are comparable to values derived from gadobutrol.
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Cardiomiopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cicatriz/diagnóstico por imagem , Meios de Contraste , Feminino , Fibrose , Coração/diagnóstico por imagem , Humanos , Masculino , Meglumina , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Compostos Organometálicos , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Recent computed tomography coronary angiography (CCTA) studies have noted higher transluminal contrast agent gradients in arteries with stenotic lesions, but the physical mechanism responsible for these gradients is not clear. We use computational fluid dynamics (CFD) modeling coupled with contrast agent dispersion to investigate the mechanism for these gradients. Simulations of blood flow and contrast agent dispersion in models of coronary artery are carried out for both steady and pulsatile flows, and axisymmetric stenoses of severities varying from 0% (unobstructed) to 80% are considered. Simulations show the presence of measurable gradients with magnitudes that increase monotonically with stenotic severity when other parameters are held fixed. The computational results enable us to examine and validate the hypothesis that transluminal contrast gradients (TCG) are generated due to the advection of the contrast bolus with time-varying contrast concentration that appears at the coronary ostium. Since the advection of the bolus is determined by the flow velocity in the artery, the magnitude of the gradient, therefore, encodes the coronary flow velocity. The correlation between the flow rate estimated from TCG and the actual flow rate in the computational model of a physiologically realistic coronary artery is 96% with a R2 value of 0.98. The mathematical formulae connecting TCG to flow velocity derived here represent a novel and potentially powerful approach for noninvasive estimation of coronary flow velocity from CT angiography.
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Meios de Contraste/metabolismo , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/metabolismo , Modelos Biológicos , Tomografia Computadorizada por Raios X , Transporte Biológico , Estenose Coronária/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/metabolismo , Vasos Coronários/fisiopatologia , Reserva Fracionada de Fluxo Miocárdico , Hemodinâmica , Humanos , HidrodinâmicaRESUMO
OBJECTIVE: To compare the changes in anti-malondialdehyde-modified low-density lipoprotein (MDA-LDL) IgG levels among patients undergoing off-pump and on-pump coronary artery bypass grafting (CABG) or valvuloplasty. SUBJECTS AND METHODS: A total of 38, 39 and 34 patients who underwent off-pump CABG, on-pump CABG and valvuloplasty, respectively, were enrolled in this study. Serum anti-MDA-LDL IgG values were measured 24 h before and after the operative procedures and at discharge. Echocardiography was also done before surgery and before discharge. The results were compared with values from 50 healthy controls. RESULTS: In all patients, a reduction in antibody titers was observed post-operatively. However, the decrease was significant only in the off-pump CABG - before surgery: 42.33 (25.83-58.51), after surgery: 30.86 (16.36-51.33) and at discharge: 10.96 (6.82-23.57; p = 0.027). There was a significant positive association between anti-MDA-LDL IgG levels and ejection fraction (r = 0.248, p = 0.036) and a negative association with E/E', a marker of pulmonary capillary wedge pressure, in the coronary patients (r = -0.345, p = 0.012), but no significant associations were found in patients with valvular heart disease. CONCLUSIONS: Serum anti-MDA-LDL IgG levels were associated with cardiac function indices in coronary patients undergoing CABG.
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Autoanticorpos/imunologia , Procedimentos Cirúrgicos Cardíacos/métodos , Doença da Artéria Coronariana/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Imunoglobulina G/imunologia , Lipoproteínas LDL/imunologia , Malondialdeído/análogos & derivados , Adulto , Idoso , Biomarcadores , Débito Cardíaco , Anuloplastia da Valva Cardíaca/métodos , Ponte de Artéria Coronária/métodos , Ecocardiografia , Feminino , Humanos , Masculino , Malondialdeído/imunologia , Pessoa de Meia-IdadeRESUMO
RATIONALE AND OBJECTIVES: This study aimed to evaluate the accuracy and reliability of educational patient pamphlets created by ChatGPT, a large language model, for common interventional radiology (IR) procedures. METHODS AND MATERIALS: Twenty frequently performed IR procedures were selected, and five users were tasked to independently request ChatGPT to generate educational patient pamphlets for each procedure using identical commands. Subsequently, two independent radiologists assessed the content, quality, and accuracy of the pamphlets. The review focused on identifying potential errors, inaccuracies, the consistency of pamphlets. RESULTS: In a thorough analysis of the education pamphlets, we identified shortcomings in 30% (30/100) of pamphlets, with a total of 34 specific inaccuracies, including missing information about sedation for the procedure (10/34), inaccuracies related to specific procedural-related complications (8/34). A key-word co-occurrence network showed consistent themes within each group of pamphlets, while a line-by-line comparison at the level of users and across different procedures showed statistically significant inconsistencies (P < 0.001). CONCLUSION: ChatGPT-generated education pamphlets demonstrated potential clinical relevance and fairly consistent terminology; however, the pamphlets were not entirely accurate and exhibited some shortcomings and inter-user structural variabilities. To ensure patient safety, future improvements and refinements in large language models are warranted, while maintaining human supervision and expert validation.
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PURPOSE: The purpose of this study was to systematically review the reported performances of ChatGPT, identify potential limitations, and explore future directions for its integration, optimization, and ethical considerations in radiology applications. MATERIALS AND METHODS: After a comprehensive review of PubMed, Web of Science, Embase, and Google Scholar databases, a cohort of published studies was identified up to January 1, 2024, utilizing ChatGPT for clinical radiology applications. RESULTS: Out of 861 studies derived, 44 studies evaluated the performance of ChatGPT; among these, 37 (37/44; 84.1%) demonstrated high performance, and seven (7/44; 15.9%) indicated it had a lower performance in providing information on diagnosis and clinical decision support (6/44; 13.6%) and patient communication and educational content (1/44; 2.3%). Twenty-four (24/44; 54.5%) studies reported the proportion of ChatGPT's performance. Among these, 19 (19/24; 79.2%) studies recorded a median accuracy of 70.5%, and in five (5/24; 20.8%) studies, there was a median agreement of 83.6% between ChatGPT outcomes and reference standards [radiologists' decision or guidelines], generally confirming ChatGPT's high accuracy in these studies. Eleven studies compared two recent ChatGPT versions, and in ten (10/11; 90.9%), ChatGPTv4 outperformed v3.5, showing notable enhancements in addressing higher-order thinking questions, better comprehension of radiology terms, and improved accuracy in describing images. Risks and concerns about using ChatGPT included biased responses, limited originality, and the potential for inaccurate information leading to misinformation, hallucinations, improper citations and fake references, cybersecurity vulnerabilities, and patient privacy risks. CONCLUSION: Although ChatGPT's effectiveness has been shown in 84.1% of radiology studies, there are still multiple pitfalls and limitations to address. It is too soon to confirm its complete proficiency and accuracy, and more extensive multicenter studies utilizing diverse datasets and pre-training techniques are required to verify ChatGPT's role in radiology.
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Radiologia , Humanos , PrevisõesRESUMO
BACKGROUND AND AIM OF THE STUDY: Cardiopulmonary bypass (CPB) is used during on-pump coronary artery bypass grafting (CABG) and heart valvular replacement surgery, and is associated with the induction of oxidative stress. The aim of the study was to assess the association between indices of cardiac function and prooxidant-antioxidant balance (PAB) values in patients undergoing valve replacement surgery and on-or off-pump CABG. METHODS: Data were obtained from 44, 33, and 41 patients undergoing off-pump CABG, on-pump CABG, and valve replacement surgery, respectively. The PAB values were measured 24 h before and after the operative procedure, and at the time of discharge. Echocardiography was performed before surgery and before discharge. RESULTS: The changes in E/E', end-diastolic volume, end-systolic volume, left ventricular diastolic and systolic diameter were significantly related to baseline PAB values. In the valve replacement group, neither baseline nor changes in PAB values were associated with echocardiographic measurements. Also, neither off-pump nor on-pump CABG were significantly different in inducing oxidative stress (p = 0.596). When PAB values were measured in CABG patients, there was a significant difference in values between the three time points (p = 0.013). In the valve replacement group, PAB values were not significantly different between the preoperative and postoperative samples. CONCLUSION: The inverse association between the level of oxidative stress and cardiac function measurement may indicate that high levels of oxidative stress may be a predictor of the deterioration of cardiac function in CABG patients. However, in valvular heart disease patients the serum PAB value was not associated with changes in cardiac function. Levels of oxidative stress, as assessed by the PAB assay, were not significantly different for patients undergoing surgery with or without CPB.
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Antioxidantes , Ponte Cardiopulmonar/efeitos adversos , Ponte de Artéria Coronária , Implante de Prótese de Valva Cardíaca , Oxidantes/metabolismo , Estresse Oxidativo , Idoso , Antioxidantes/análise , Antioxidantes/metabolismo , Benzidinas , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/cirurgia , Compostos Cromogênicos , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Feminino , Testes de Função Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Estatística como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: It has been reported that obesity is associated with higher levels of oxidative stress. We aimed to evaluate the hypothesis that pro-oxidant antioxidant balance (PAB) values could be affected by adiposity and to assess the association between PAB levels and indices of obesity. METHODS: Subjects (n = 733) were recruited and tlen were divided into 3 groups of normal-weight (BMI < 25, n = 207), overweight (25 < BMI < 30, n = 375), and obese (BMI > 30, n = 151). PAB values were measured in all participants. RESULTS: There was a significant association between PAB values and weight when the correlation was determined for all subjects (p < 0.05). Obese subject had significantly higher levels of PAB values [40.8 (34.3 - 51.1) HK unit] compared with overweight [37.5 (29.7 - 47.3) HK unit] and normal-weight subjects [37.2 (29.6 - 45.2) HK unit] (p < 0.05 in each case). However, there was no significant difference in PAB values between normal and over-weight subjects (p > 0.05). On performing the analysis of covariance, low-density lipoprotein-cholesterol (LDL-C) was found to have a significant independent association with PAB values (j = 0.046, p = 0.04). CONCLUSIONS: The high levels of PAB values in obese subjects without overt signs/symptoms of cardiovascular disease may be related to a heightened state of oxidative stress associated with obesity.
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Antioxidantes/metabolismo , Peso Corporal , Espécies Reativas de Oxigênio/sangue , Adulto , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Obesidade , Valores de ReferênciaRESUMO
PURPOSE: We assessed the impact of bicuspid aortic valve (BAV), aortic stenosis (AS), and regurgitation (AR) on the metrics of left ventricular (LV) remodeling, as measured by electrocardiogram (ECG), transthoracic echocardiography (TTE), and cardiac magnetic resonance (CMR). METHODS: This retrospective CMR study included 11 patients with both AS and AR (BAV-ASR), 30 with AS (BAV-AS), 28 with AR (BAV-AR), 47 with neither AS nor AR (BAV-no_AS/AR), and 40 with trileaflet aortic valve (TAV-no_AS/AR). CMR analysis included the LV end-diastolic volume index (LVEDVi), mass index (LVMi), and extracellular volume fraction (ECV). The Sokolow-Lyon and Cornell products by ECG and TTE-derived E/e' were measured. RESULTS: There were no differences in the ECG, TTE, and CMR parameters between BAV-no_AS/AR and TAV-no_AS/AR. However, the presence of aortic valve dysfunction resulted in an elevated Sokolow-Lyon product for BAV-ASR (p = 0.017) and BAV-AR (p = 0.001), as well as increased Cornell product (p = 0.04) and E/e' (p < 0.001) for BAV-AS compared with BAV-no_AS/AR. LVEDVi and LVMi were elevated in patients with BAV-ASR and BAV-AR compared with those with BAV-no_AS/AR (LVEDVi: 101 ± 29 ml/m2 and 112 ± 32 ml/m2 vs. 74 ± 15 ml/m2, p = 0.005 and p < 0.001, LVMi: 75 ± 7 g/m2 and 64 ± 14 g/m2 vs. 47 ± 9 g/m2, respectively; p < 0.001). There was no difference in ECV between the BAV and TAV-no_AS/AR subgroups. CONCLUSION: Normally functioning BAV did not result in LV remodeling. However, concomitant AV dysfunction was associated with statistically significant morphological remodeling.
Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Estenose da Valva Mitral , Humanos , Doença da Válvula Aórtica Bicúspide/complicações , Estudos Retrospectivos , Remodelação Ventricular , Valor Preditivo dos Testes , Valva AórticaRESUMO
OBJECTIVES: Cardiac surgeries initiate oxidative stress, increasing organ dysfunction development and mortality. The present study investigated the superoxide dismutase (SOD) activity, as an antioxidant enzyme, in patients undergoing coronary artery bypass (CABG) and heart valve replacement surgeries. METHODS: A prospective study was performed on patients with proven coronary artery disease (CAD) or valvular heart disease (VHD) candidates for on- or off-pump CABG and valve replacement surgery. Serum SOD activity was measured preoperatively, at 24 h postoperatively, and at the time of discharge. In addition, echocardiography was performed before surgery and at discharge. RESULTS: A total of 48, 51, and 47 patients were enrolled in the on-pump, off-pump CABG, and valve replacement groups, respectively. Baseline serum SOD activity showed no significant association with BMI, age, and blood pressure in either CAD or VHD patients. The SOD values decreased at the 24 h postoperative time and then increased at the time of discharge in all groups, except for a slight decrease in the on-pump group. The changes in serum SOD values were not significantly different for the three surgical groups. CONCLUSIONS: The serum SOD activities fell significantly after CABG and valve replacement surgery. Further investigation is emphasized for the role of SOD in oxidative stress after cardiac surgery.
Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana , Humanos , Antioxidantes , Estudos Prospectivos , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Superóxido Dismutase , Resultado do TratamentoRESUMO
OBJECTIVES: We studied the association between the prooxidant-antioxidant balance (PAB), anti-malondialdehyde-modified low-density lipoprotein (oxidized LDL, ox-LDL) IgG antibody and indices of cardiac function (systolic and diastolic function) in patients with coronary artery disease (CAD). METHODS: Fifty-five patients with established CAD were selected, and serum levels of anti-ox-LDL IgG and PAB values were measured and compared with 40 matched healthy controls. Systolic and diastolic functions were determined for all patients. RESULTS: PAB values were significantly higher in patients than in controls (p < 0.001), whilst serum anti-ox-LDL concentrations were not statistically different between the 2 groups (p = 0.821). However, after adjustment for high-density lipoprotein cholesterol, the patients had higher anti-ox-LDL levels (p = 0.04). Total PAB values were inversely associated with ejection fraction (r = -0.326, p = 0.031), but this was not the case for anti-ox-LDL in either group (p > 0.05). CONCLUSION: Serum concentrations of a marker of oxidative stress (PAB values) are inversely associated with cardiac function. PAB is a relatively simple index that could be incorporated into risk assessment in CAD patients. Anti-ox-LDL IgG antibody concentration does not appear to reflect total oxidative stress as assessed by PAB.
Assuntos
Anticorpos/metabolismo , Antioxidantes/metabolismo , Doença da Artéria Coronariana/fisiopatologia , Imunoglobulina G/metabolismo , Lipoproteínas LDL/imunologia , Biomarcadores/metabolismo , Doença da Artéria Coronariana/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/imunologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
A randomized controlled clinical trial in 196 obese subjects was performed to examine the effectiveness of body acupuncture on body weight loss, lipid profile and immunogenic and inflammatory markers. Subjects received authentic (cases) or sham (controls) acupuncture for 6 weeks in combination with a low-calorie diet. In the following 6 weeks, they received the low-calorie diet alone. Subjects were assessed at the beginning, 6 and 12 weeks later. Heat shock protein (Hsps)-27, 60, 65, 70 antibody titers and high sensitivity C-reactive protein (hs-CRP) levels were also assessed. A significant reduction in measures of adiposity and improvement in lipid profile were observed in both groups, but the levels of anti-Hsp-antibodies decreased in cases only. A reduction in anthropometric and lipid profile in cases were sustained in the second period, however, only changes in lipid profile were observed in the control group. Anti-Hsp-antibodies and hs-CRP levels continued to be reduced in cases but in controls only the reduction in hs-CRP remained. Changes in anthropometric parameters, lipid profile, and anti-Hsp-antibodies were more evident in cases. Body acupuncture in combination with diet restriction was effective in enhancing weight loss and improving dyslipidemia.
Assuntos
Terapia por Acupuntura , Antropometria , Proteínas de Choque Térmico/imunologia , Lipídeos/sangue , Obesidade/terapia , Redução de Peso , Adolescente , Adulto , Biomarcadores , Índice de Massa Corporal , Peso Corporal , Proteína C-Reativa/metabolismo , Restrição Calórica , Humanos , Pessoa de Meia-IdadeRESUMO
The trace elements copper (Cu) and zinc (Zn) are essential for maintaining oxidative balance, and cardiac surgery is known to provoke an increase in oxidative stress. We investigated the variations in serum Zn and Cu concentrations before and after surgery in patients undergoing on- and off-pump CABG and heart valve replacement. We performed a prospective study on patients undergoing on- or off-pump CABG, or heart valve replacement surgery (48, 51, and 47 patients, respectively). Venous blood samples were obtained, and serum Cu and Zn concentrations were measured preoperatively, 24 h postoperatively, and the time of discharge. In addition, echocardiography was carried out on all patients before surgery and again on the day of discharge. We found the temporal changes in Cu, Zn, and Zn/Cu ratio were significantly different in all three groups of surgery (p < 0.05). In each group, Cu and Zn values and Zn/Cu ratio decreased at the 24-h postoperative time and rose at the discharge time. There were no significant differences between surgery groups in the changes induced in Zn or Cu values (p > 0.05). In conclusion, the concentrations of Cu and Zn were markedly reduced after on- and off-pump CABG and valve replacement surgery. This may suggest that supplementary Zn and Cu administration could be beneficial during open-heart surgeries. However, more long-term studies with more patients are needed to confirm this hypothesis.