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1.
Front Cardiovasc Med ; 11: 1279298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374997

RESUMO

Introduction: Cardiac magnetic resonance (CMR) is of diagnostic and prognostic value in a range of cardiopulmonary conditions. Current methods for evaluating CMR studies are laborious and time-consuming, contributing to delays for patients. As the demand for CMR increases, there is a growing need to automate this process. The application of artificial intelligence (AI) to CMR is promising, but the evaluation of these tools in clinical practice has been limited. This study assessed the clinical viability of an automatic tool for measuring cardiac volumes on CMR. Methods: Consecutive patients who underwent CMR for any indication between January 2022 and October 2022 at a single tertiary centre were included prospectively. For each case, short-axis CMR images were segmented by the AI tool and manually to yield volume, mass and ejection fraction measurements for both ventricles. Automated and manual measurements were compared for agreement and the quality of the automated contours was assessed visually by cardiac radiologists. Results: 462 CMR studies were included. No statistically significant difference was demonstrated between any automated and manual measurements (p > 0.05; independent T-test). Intraclass correlation coefficient and Bland-Altman analysis showed excellent agreement across all metrics (ICC > 0.85). The automated contours were evaluated visually in 251 cases, with agreement or minor disagreement in 229 cases (91.2%) and failed segmentation in only a single case (0.4%). The AI tool was able to provide automated contours in under 90 s. Conclusions: Automated segmentation of both ventricles on CMR by an automatic tool shows excellent agreement with manual segmentation performed by CMR experts in a retrospective real-world clinical cohort. Implementation of the tool could improve the efficiency of CMR reporting and reduce delays between imaging and diagnosis.

2.
Nat Commun ; 14(1): 5065, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37604803

RESUMO

Pronounced immune escape by the SARS-CoV-2 Omicron variant has resulted in many individuals possessing hybrid immunity, generated through a combination of vaccination and infection. Concerns have been raised that omicron breakthrough infections in triple-vaccinated individuals result in poor induction of omicron-specific immunity, and that prior SARS-CoV-2 infection is associated with immune dampening. Taking a broad and comprehensive approach, we characterize mucosal and blood immunity to spike and non-spike antigens following BA.1/BA.2 infections in triple mRNA-vaccinated individuals, with and without prior SARS-CoV-2 infection. We find that most individuals increase BA.1/BA.2/BA.5-specific neutralizing antibodies following infection, but confirm that the magnitude of increase and post-omicron titres are higher in the infection-naive. In contrast, significant increases in nasal responses, including neutralizing activity against BA.5 spike, are seen regardless of infection history. Spike-specific T cells increase only in infection-naive vaccinees; however, post-omicron T cell responses are significantly higher in the previously-infected, who display a maximally induced response with a highly cytotoxic CD8+ phenotype following their 3rd mRNA vaccine dose. Responses to non-spike antigens increase significantly regardless of prior infection status. These findings suggest that hybrid immunity induced by omicron breakthrough infections is characterized by significant immune enhancement that can help protect against future omicron variants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/classificação , Vacinas contra COVID-19/administração & dosagem , Imunidade , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes , Imunoglobulina A , Linfócitos T/imunologia , Imunidade nas Mucosas , Masculino , Feminino , Adulto
3.
BJS Open ; 7(2)2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-37104754

RESUMO

BACKGROUND: Myocardial injury after non-cardiac surgery is diagnosed following asymptomatic troponin elevation in the perioperative interval. Myocardial injury after non-cardiac surgery is associated with high mortality rates and significant rates of major adverse cardiac events within the first 30 days following surgery. However, less is known regarding its impact on mortality and morbidity beyond this time. This systematic review and meta-analysis aimed to establish the rates of long-term morbidity and mortality associated with myocardial injury after non-cardiac surgery. METHODS: MEDLINE, Embase and Cochrane CENTRAL were searched, and abstracts screened by two reviewers. Observational studies and control arms of trials, reporting mortality and cardiovascular outcomes beyond 30 days in adult patients diagnosed with myocardial injury after non-cardiac surgery, were included. Risk of bias was assessed using the Quality in Prognostic Studies tool. A random-effects model was used for the meta-analysis of outcome subgroups. RESULTS: Searches identified 40 studies. The meta-analysis of 37 cohort studies found a rate of major adverse cardiac events-associated myocardial injury after non-cardiac surgery of 21 per cent and mortality following myocardial injury after non-cardiac surgery was 25 per cent at 1-year follow-up. A non-linear increase in mortality rate was observed up to 1 year after surgery. Major adverse cardiac event rates were also lower in elective surgery compared with a subgroup including emergency cases. The analysis demonstrated a wide variety of accepted myocardial injury after non-cardiac surgery and major adverse cardiac events diagnostic criteria within the included studies. CONCLUSION: A diagnosis of myocardial injury after non-cardiac surgery is associated with high rates of poor cardiovascular outcomes up to 1 year after surgery. Work is needed to standardize diagnostic criteria and reporting of myocardial injury after non-cardiac surgery-related outcomes. REGISTRATION: This review was prospectively registered with PROSPERO in October 2021 (CRD42021283995).


Assuntos
Doenças Cardiovasculares , Procedimentos Cirúrgicos Eletivos , Adulto , Humanos , Doenças Cardiovasculares/etiologia
4.
Chest ; 164(3): 700-716, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36965765

RESUMO

BACKGROUND: Microvascular abnormalities and impaired gas transfer have been observed in patients with COVID-19. The progression of pulmonary changes in these patients remains unclear. RESEARCH QUESTION: Do patients hospitalized with COVID-19 without evidence of architectural distortion on structural imaging exhibit longitudinal improvements in lung function measured by using 1H and 129Xe MRI between 6 and 52 weeks following hospitalization? STUDY DESIGN AND METHODS: Patients who were hospitalized with COVID-19 pneumonia underwent a pulmonary 1H and 129Xe MRI protocol at 6, 12, 25, and 51 weeks following hospital admission in a prospective cohort study between November 2020 and February 2022. The imaging protocol was as follows: 1H ultra-short echo time, contrast-enhanced lung perfusion, 129Xe ventilation, 129Xe diffusion-weighted, and 129Xe spectroscopic imaging of gas exchange. RESULTS: Nine patients were recruited (age 57 ± 14 [median ± interquartile range] years; six of nine patients were male). Patients underwent MRI at 6 (n = 9), 12 (n = 9), 25 (n = 6), and 51 (n = 8) weeks following hospital admission. Patients with signs of interstitial lung damage were excluded. At 6 weeks, patients exhibited impaired 129Xe gas transfer (RBC to membrane fraction), but lung microstructure was not increased (apparent diffusion coefficient and mean acinar airway dimensions). Minor ventilation abnormalities present in four patients were largely resolved in the 6- to 25-week period. At 12 weeks, all patients with lung perfusion data (n = 6) showed an increase in both pulmonary blood volume and flow compared with 6 weeks, although this was not statistically significant. At 12 weeks, significant improvements in 129Xe gas transfer were observed compared with 6-week examinations; however, 129Xe gas transfer remained abnormally low at weeks 12, 25, and 51. INTERPRETATION: 129Xe gas transfer was impaired up to 1 year following hospitalization in patients who were hospitalized with COVID-19 pneumonia, without evidence of architectural distortion on structural imaging, whereas lung ventilation was normal at 52 weeks.


Assuntos
COVID-19 , Isótopos de Xenônio , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Pulmão/diagnóstico por imagem
5.
Int Urogynecol J ; 30(1): 33-41, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29951909

RESUMO

INTRODUCTION AND HYPOTHESIS: Understanding patients' concerns and goals is essential for providing individualised care in urogynaecology. The study objectives were to undertake a content analysis of free-text concerns and goals recorded by patients using an electronic pelvic-floor questionnaire (ePAQ-PF) and measure how these related to self-reported symptom and health-related quality-of-life (HRQOL) data also recorded using ePAQ-PF. METHODS: A total of 1996 consenting patients completed ePAQ-PF. Content analysis was undertaken of free-text responses to the item: 'Considering the issues that currently concern you the most, what do you hope to achieve from any help, advice or treatment?' Key content themes were identified by the lead researcher, and three researchers read and coded all recorded responses. Student's t test was used to compare ePAQ-PF domain scores for patients reporting concerns in the relevant domain with those who did not. RESULTS: In total, 63% of participants who completed the questionnaire, recorded at least one free-text item. Content analysis identified 1560 individual concerns coding into the 19 ePAQ-PF domains. Symptom scores were significantly higher for patients reporting free-text concerns in 18 domains (p < 0.05). Additional concerns relating specifically to body image were recorded by 11% of patients. Key areas of importance emerging for personal goals included cure/improvement, better understanding, incontinence pad use, sexual function and surgery. CONCLUSIONS: Free-text reporting in ePAQ-PF is utilised by patients and facilitates self-expression and discussion of issues impacting on HRQOL. The significant relationship between recorded free-text concerns and ePAQ-PF domain scores suggests convergent validity for the instrument. Development and psychometric testing of a domain to assess body image is proposed.


Assuntos
Distúrbios do Assoalho Pélvico/psicologia , Incontinência Fecal/psicologia , Feminino , Objetivos , Humanos , Inquéritos e Questionários , Incontinência Urinária/psicologia
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