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Intracoronary continuous thermodilution has been recently proposed as an invasive method to quantify absolute coronary flow (Qabs) and resistance (Rabs) in vivo. The aim of the present study is to develop and validate of a novel pressure-wire- and microcatheter-free surrogate of coronary flow and resistance derived from a standard coronary angiogram. Angiography derived coronary flow (Qangio) and resistance (Rangio) was prospectively validated in a two-center cohort of patients from Oxford Heart Centre and the Essex Cardiothoracic Centre. Qabs and Rabs were measured during resting and hyperemic conditions with continuous thermodilution using the Rayflow microcatheter. Qangio and Rangio were computed from the diagnostic coronary angiogram in a blinded fashion in resting and hyperemic conditions. A total of 62 patients and 115 vessels were included in the present analysis. The median Qabs at rest was 75 ml/min (53-95) and 151 ml/min (105-203) during hyperemia; Qangio at rest was 84 ml/min (66-108) and 154 ml/min (115-195) during hyperemia. There was a strong correlation between Qabs and Qangio (R = 0,72; p < 0.001, R = 0,86; p < 0.001 respectively) with satisfactory interclass correlation (0.841, 95% CI 0.509-0.957; p = 0.0003). The median Rabs was 1111 mmHg/(L/min) (830-1581.4) at rest and 454 mmHg/(L/min) (348-610) during hyperemia; angiographic resistance (Rangio) was 937.4 mmHg/(L/min) (695.4-1261.9) at rest and 492.4 mmHg/(L/min) (406-697) during hyperemia. There was a strong correlation between Rabs and Rangio in both conditions (R = 0,81; p < 0.001 and R = 0,78; p < 0.001 respectively). The was a good correlation between absolute coronary flow reserve (CFR) and angiography-derived CFR (R = 0,61; p < 0.001) and between absolute microvascular resistance reserve (MRR) and angiography-derived MRR (R = 0,49; p < 0.001).
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After myocardial infarction (MI), patients with type 2 diabetes have an increased rate of adverse outcomes, compared to patients without. Diabetes confers a 1.5-2-fold increase in early mortality and, importantly, this discrepancy has been consistent over recent decades, despite advances in treatment and overall survival. Certain assumptions have emerged to explain this increased risk, such as differences in infarct size or coronary artery disease severity. Here, we re-evaluate that evidence and show how contemporary analyses using state-of-the-art characterization tools suggest that the received wisdom tells an incomplete story. Simultaneously, epidemiological and mechanistic biological data suggest additional factors relating to processes of diabetes-related inflammation might play a prominent role. Inflammatory processes after MI mediate injury and repair and are thus a potential therapeutic target. Recent studies have shown how diabetes affects immune cell numbers and drives changes in the bone marrow, leading to pro-inflammatory gene expression and functional suppression of healing and repair. Here, we review and re-evaluate the evidence around adverse prognosis in patients with diabetes after MI, with emphasis on how targeting processes of inflammation presents unexplored, yet valuable opportunities to improve cardiovascular outcomes in this vulnerable patient group.
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Acute coronary syndromes (ACS) are one of the leading causes of mortality worldwide, with atherosclerotic plaque rupture and subsequent thrombus formation as the main underlying substrate. Thrombus burden evaluation is important for tailoring treatment therapy and predicting prognosis. Coronary optical coherence tomography (OCT) enables in-vivo visualization of thrombus that cannot otherwise be achieved by other image modalities. However, automatic quantification of thrombus on OCT has not been implemented. The main challenges are due to the variation in location, size and irregularities of thrombus in addition to the small data set. In this paper, we propose a novel dual-coordinate cross-attention transformer network, termed DCCAT, to overcome the above challenges and achieve the first automatic segmentation of thrombus on OCT. Imaging features from both Cartesian and polar coordinates are encoded and fused based on long-range correspondence via multi-head cross-attention mechanism. The dual-coordinate cross-attention block is hierarchically stacked amid convolutional layers at multiple levels, allowing comprehensive feature enhancement. The model was developed based on 5,649 OCT frames from 339 patients and tested using independent external OCT data from 548 frames of 52 patients. DCCAT achieved Dice similarity score (DSC) of 0.706 in segmenting thrombus, which is significantly higher than the CNN-based (0.656) and Transformer-based (0.584) models. We prove that the additional input of polar image not only leverages discriminative features from another coordinate but also improves model robustness for geometrical transformation.Experiment results show that DCCAT achieves competitive performance with only 10% of the total data, highlighting its data efficiency. The proposed dual-coordinate cross-attention design can be easily integrated into other developed Transformer models to boost performance.
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Circulação Coronária , Edema Cardíaco , Cardiomiopatia de Takotsubo , Cardiomiopatia de Takotsubo/fisiopatologia , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Humanos , Edema Cardíaco/fisiopatologia , Edema Cardíaco/diagnóstico por imagem , Edema Cardíaco/etiologia , Miocárdio/patologia , Valor Preditivo dos Testes , Função Ventricular Esquerda , Angiografia Coronária , PrognósticoRESUMO
Background: The assessment of coronary microvascular dysfunction (CMD) using invasive methods is a field of growing interest, however the preferred method remains debated. Bolus and continuous thermodilution are commonly used methods, but weak agreement has been observed in patients with angina with non-obstructive coronary arteries (ANOCA). This study examined their agreement in revascularized acute coronary syndromes (ACS) and chronic coronary syndromes (CCS) patients. Objective: To compare bolus thermodilution and continuous thermodilution indices of CMD in revascularized ACS and CCS patients and assess their diagnostic agreement at pre-defined cut-off points. Methods: Patients from two centers underwent paired bolus and continuous thermodilution assessments after revascularization. CMD indices were compared between the two methods and their agreements at binary cut-off points were assessed. Results: Ninety-six patients and 116 vessels were included. The mean age was 64 ± 11 years, and 20 (21 %) were female. Overall, weak correlations were observed between the Index of Microcirculatory Resistance (IMR) and continuous thermodilution microvascular resistance (Rµ) (rho = 0.30p = 0.001). The median coronary flow reserve (CFR) from continuous thermodilution (CFRcont) and bolus thermodilution (CFRbolus) were 2.19 (1.76-2.67) and 2.55 (1.50-3.58), respectively (p < 0.001). Weak correlation and agreement were observed between CFRcont and CFRbolus (rho = 0.37, p < 0.001, ICC 0.228 [0.055-0.389]). When assessed at CFR cut-off values of 2.0 and 2.5, the methods disagreed in 41 (35 %) and 45 (39 %) of cases, respectively. Conclusions: There is a significant difference and weak agreement between bolus and continuous thermodilution-derived indices, which must be considered when diagnosing CMD in ACS and CCS patients.
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PURPOSE: To evaluate the prevalence and incidence of significant structural heart disease in targeted patients with cardiac symptoms referred by general practitioners (GPs) using open access echocardiography, without prior clinical evaluation by a cardiologist. DESIGN: Data were derived from 488 subjects who underwent transthoracic echocardiography between January and April 2018. Patients were referred directly by GPs in East Berkshire, South England, through an online platform. Echocardiography was performed within 4-6 weeks of referral and all reports were assessed by a consultant cardiologist with expedited follow-up facilitated pro re nata. Results were analysed to determine the frequency of detection of structural abnormalities, particularly of the left ventricle and cardiac valves. RESULTS: Echocardiography was prospectively performed in consecutive subjects (50% male, mean (±SD) age 68.5±22 years; 50% female; mean (±SD) 64.6 (±19.1)). At least one abnormality likely to change management was found in 133 (27.3%) of all open access echocardiograms. Clinical heart failure with left ventricular systolic dysfunction (LVSD) and diastolic dysfunction was confirmed in 46 (9%) and 69 (14%), respectively. Of the 46 patients with LVSD, 33 were new diagnoses. Significant cardiac valve disease was found in 42 (8.6%) patients. 12 of these had known valvular disease or previous valvular surgery, and 30 were new diagnoses. CONCLUSION: Major structural and functional cardiac abnormalities are common in late middle-aged patients who present to GPs with cardiac symptoms and signs. Reported, unrestricted open access echocardiography enables early detection of significant cardiac pathology and timely intervention may improve cardiovascular outcomes.
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Cardiopatias Congênitas , Insuficiência Cardíaca , Doenças das Valvas Cardíacas , Disfunção Ventricular Esquerda , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Acesso à Informação , Ecocardiografia/métodos , Insuficiência Cardíaca/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologiaRESUMO
PURPOSE: To evaluate the prevalence and incidence of significant structural heart disease in targeted patients with cardiac symptoms referred by general practitioners (GPs) using open access echocardiography, without prior clinical evaluation by a cardiologist. DESIGN: Data were derived from 488 subjects who underwent transthoracic echocardiography between January and April 2018. Patients were referred directly by GPs in East Berkshire, South England, through an online platform. Echocardiography was performed within 4-6 weeks of referral and all reports were assessed by a consultant cardiologist with expedited follow-up facilitated pro re nata. Results were analysed to determine the frequency of detection of structural abnormalities, particularly of the left ventricle and cardiac valves. RESULTS: Echocardiography was prospectively performed in consecutive subjects (50% male, mean (±SD) age 68.5±22 years; 50% female; mean (±SD) 64.6 (±19.1)). At least one abnormality likely to change management was found in 133 (27.3%) of all open access echocardiograms. Clinical heart failure with left ventricular systolic dysfunction (LVSD) and diastolic dysfunction was confirmed in 46 (9%) and 69 (14%), respectively. Of the 46 patients with LVSD, 33 were new diagnoses. Significant cardiac valve disease was found in 42 (8.6%) patients. 12 of these had known valvular disease or previous valvular surgery, and 30 were new diagnoses. CONCLUSION: Major structural and functional cardiac abnormalities are common in late middle-aged patients who present to GPs with cardiac symptoms and signs. Reported, unrestricted open access echocardiography enables early detection of significant cardiac pathology and timely intervention may improve cardiovascular outcomes.
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BACKGROUND: Diagnostic errors are well documented in the literature and emphasise the need to teach diagnostic skills at an early stage in medical school to create effective and safe clinicians. Hence, there may be a place for diagnostic aids (such as the Surgical Sieve) that provide a framework for generating ideas about diagnoses. With repeated use of the Surgical Sieve in teaching sessions with students, and prompted by the traditional handheld wheels used in antenatal clinics, we developed the Compass Medicine, a handheld diagnostic wheel comprising three concentric discs attached at the centre. We report a preliminary study comparing the Surgical Sieve and the Compass Medicine in generating differential diagnoses. METHODS: A total of 48 third-year medical students from Cardiff University participated in a study aimed at measuring the efficacy of diagnostic aids (Surgical Sieve and Compass Medicine) in generating diagnoses. We quantified the effect each aid had on the number of diagnoses generated, and compared the size of the effect between the two diagnostic aids. There may be a place for diagnostic aids that provide a framework for generating ideas about diagnoses RESULTS: The study suggests that both diagnostic aids prompted users to generate a greater number of diagnoses, but there was no significant difference in the size of effect between the two diagnostic aids. DISCUSSION: We hope that our study with diagnostic aids will encourage the use of robust tools to teach medical students an easily visualised framework for diagnostic thinking.
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Competência Clínica , Diagnóstico , Educação de Graduação em Medicina/métodos , Estudantes de Medicina/psicologia , Diagnóstico Diferencial , Humanos , Medicina , Faculdades de MedicinaRESUMO
BACKGROUND: Although the majority of thyroid nodules are benign the process of excluding malignancy is challenging and sometimes involves unnecessary surgical procedures. We explored the development of a predictive model for malignancy in thyroid nodules by integrating a combination of simple demographic, biochemical, and ultrasound characteristics. METHODS: Retrospective case-record review. We reviewed records of patients with thyroid nodules referred to our institution from 2004 to 2011 (n = 536; female 84 %, mean age 51 years). All malignancy was proven histologically while benign disease was either confirmed histologically, or on cytology with minimum 36-month observation period. We focused on the following predictors: age, sex, smoking status, thyroid hormones (FT4 and TSH) and nodule characteristics on ultrasound. Variables were included in a multivariate logistic regression and bootstrap analyses were used to confirm results. RESULTS: Independent predictors of malignancy in the fully adjusted model were TSH (OR 1.53, 95 % CI 1.10, 2.12, p = 0.01), male gender (OR 3.45, 95 % CI 1.33, 8.92, p = 0.01), microcalcifications (OR 6.32, 95 % CI 2.82, 14.1, p < 0.001), and irregular nodule margins (OR 5.45, 95 % CI 1.61, 18.6, p = 0.006) Bootstrap analyses strengthened these associations and a parsimonious analysis consisting of these variables and age-group demonstrated an area under the curve of 0.77. A predictive score was sensitive (86.9 %) at low scores and highly specific (94.87 %) at higher scores for distinguishing benign from malignant disease. CONCLUSIONS: A predictive model for malignancy using a combination of clinical, biochemical, and radiological characteristics may support clinicians in reducing unnecessary invasive procedures in patients with thyroid nodules.