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1.
J Cardiovasc Magn Reson ; 25(1): 12, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36755302

RESUMO

BACKGROUND: Data regarding cardiovascular magnetic resonance (CMR) reference values in athletes have not been well determined yet. Using CMR normal reference values derived from the general population may be misleading in athletes and may have clinical implications. AIMS: To determine reference ventricular dimensions and function parameters and ratios by CMR in high performance athletes. METHODS: Elite athletes and age- and gender-matched sedentary healthy controls were included. Anatomical and functional variables, including biventricular volumes, mass, systolic function, wall thickness, sphericity index and longitudinal function were determined by CMR. RESULTS: A total of 148 athletes (29.2 ± 9.1 years; 64.8% men) and 124 controls (32.1 ± 10.5 years; 67.7% men) were included. Left ventricular (LV) mass excluding papillary muscles was 67 ± 13 g/m2 in the control group and increased from 65 ± 14 g/m2 in the low intensity sport category to 83 ± 16 g/m2 in the high cardiovascular demand sport category; P < 0.001. Regarding right ventricular (RV) mass, the data were 20 ± 5, 31 ± 6, and 38 ± 8 g/m2, respectively; P < 0.001. LV and RV volumes, and wall thickness were higher in athletes than in the control group, and also increased with sport category. However, LV and RV ejection fractions were similar in both groups. LV and RV dimensions, wall thickness and LV/RV ratios reference parameters for athletes are provided. CONCLUSIONS: LV and RV masses, volumes, and wall thicknesses are higher in athletes than in sedentary subjects. Specific CMR reference ranges for athletes are provided and can be used as reference levels, rather than the standard upper limits used for the general population to exclude cardiomyopathy.


Assuntos
Coração , Imageamento por Ressonância Magnética , Masculino , Humanos , Feminino , Valor Preditivo dos Testes , Ventrículos do Coração/diagnóstico por imagem , Volume Sistólico , Atletas , Função Ventricular Direita , Espectroscopia de Ressonância Magnética , Função Ventricular Esquerda/fisiologia
2.
J Cardiovasc Magn Reson ; 22(1): 70, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32981526

RESUMO

BACKGROUND: Cocaine is an addictive, sympathomimetic drug with potentially lethal effects. We have previously shown with cardiovascular magnetic resonance (CMR) the presence of cardiovascular involvement in a significant percentage of consecutive asymptomatic cocaine addicts. CMR with feature-tracking analysis (CMR-FT) allows for the quantification of myocardial deformation which may detect preclinical involvement. Therefore, we aimed to assess the effects of cocaine on the left ventricular myocardium in a group of asymptomatic cocaine users with CMR-FT. METHODS: In a cohort of asymptomatic cocaine addicts (CA) who had been submitted to CMR at 3 T, we used CMR-FT to measure strain, strain rate and dyssynchrony index in CA with mildly decreased left ventricular ejection fraction (CA-LVEFd) and in CA with preserved ejection fraction (CA-LVEFp). We also measured these parameters in 30 age-matched healthy subjects. RESULTS: There were no differences according to age. Significant differences were seen in global longitudinal, radial and circumferential strain, in global longitudinal and radial strain rate and in radial and circumferential dyssynchrony index among the groups, with the lowest values in CA-LVEFd and intermediate values in CA-LVEFp. Longitudinal, radial and circumferential strain values were significantly lower in CA-LVEFp with respect to controls. CONCLUSIONS: CA-LVEFp show decreased systolic strain and strain rate values, with intermediate values between healthy controls and CA-LVEFd. Signs suggestive of dyssynchrony were also detected. In CA, CMR-FT based strain analysis can detect early subclinical myocardial involvement.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Usuários de Drogas , Imagem Cinética por Ressonância Magnética , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda/efeitos dos fármacos , Adulto , Doenças Assintomáticas , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sístole , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologia
3.
J Magn Reson Imaging ; 47(5): 1415-1425, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29205626

RESUMO

BACKGROUND: The measurement of myocardial deformation by strain analysis is an evolving tool to quantify regional and global myocardial function. PURPOSE: To assess the feasibility and reproducibility of myocardial strain/strain rate measurements with magnetic resonance feature tracking (MR-FT) in healthy subjects and in patient groups. STUDY TYPE: Prospective study. POPULATION: Sixty patients (20 hypertensives with left ventricular (LV) hypertrophy (H); 20 nonischemic dilated cardiomyopathy (D); 20 ischemic heart disease (I); as well as 20 controls (C) were included, 10 men and 10 women in each group. FIELD STRENGTH/SEQUENCE: A 1.5T MR protocol including steady-state free precession (SSFP) cine sequences in the standard views and late enhancement sequences. ASSESSMENT: LV volumes, mass, global and regional radial, circumferential, and longitudinal strain/strain rate were measured using CVI42 software. The analysis time was recorded. STATISTICAL TESTS: Intraobserver and interobserver agreement and intraclass correlation coefficients (ICC) were obtained for reproducibility assessment as well as differences according to gender and group of pertinence. RESULTS: Strain/strain rate analysis could be achieved in all subjects. The average analysis time was 14 ± 3 minutes. The average intraobserver ICC was excellent (ICC >0.90) for strain and good (ICC >0.75) for strain rate. Reproducibility of strain measurements was good to excellent (ICC >0.75) for all groups of subjects and both genders. Reproducibility of strain measurements was good for basal segments (ICC >0.75) and excellent for middle and apical segments (ICC >0.90). Reproducibility of strain rate measurements was moderate for basal segments (ICC >0.50) and good for middle and apical segments. DATA CONCLUSION: MR-FT for strain/strain rate analysis is a feasible and highly reproducible technique. CVI42 FT analysis was equally feasible and reproducible in various pathologies and between genders. Better reproducibility was seen globally for middle and apical segments, which needs further clarification. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2018;47:1415-1425.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Imageamento por Ressonância Magnética , Isquemia Miocárdica/diagnóstico por imagem , Idoso , Eletrocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estresse Mecânico , Função Ventricular Esquerda
4.
J Cardiovasc Magn Reson ; 18(1): 64, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27719670

RESUMO

BACKGROUND: Left and right atrial function show a different pattern in advanced age in order to maintain adequate ventricular filling. It has been shown that left atrial (LA) function has a prognostic value in a number of heart conditions. Cardiovascular magnetic resonance (CMR) provides high quality images of the left and right atria using high temporal resolution steady state free precession (SSFP) cine sequences. We used SSFP cines to characterize atrial function in healthy, normotensive, volunteers. METHODS: We measured maximum, preatrial contraction and minimum left and right atrial volumes in 120 healthy subjects after careful exclusion of cardiovascular abnormality (60 men, 60 women; 20 subjects per age decile from 20 to 80 years). Data were generated from 3-dimensional modeling, including tracking of the atrioventricular ring motion and time-volume curves analysis. With those measurements, all the usual parameters for left and right atrial function were calculated. RESULTS: Gender had significant influence on some parameters of left and right atrial conduit and booster pump function. Age significantly influenced the majority of parameters of both left and right atrial function, with typically lower reservoir and conduit functions and higher booster pump function, both in males and females belonging to older age groups. CMR normal ranges were modelled for clinical use with normalization, where appropriate, for body surface area and gender, displaying parameters with respect to age. CONCLUSIONS: CMR normal reference ranges for components of left and right atrial function are provided for males and females for a wide age range.


Assuntos
Átrios do Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda , Função Ventricular Direita , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Fatores Sexuais , Adulto Jovem
5.
J Cardiovasc Magn Reson ; 17: 29, 2015 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-25928314

RESUMO

Morphological and functional parameters such as chamber size and function, aortic diameters and distensibility, flow and T1 and T2* relaxation time can be assessed and quantified by cardiovascular magnetic resonance (CMR). Knowledge of normal values for quantitative CMR is crucial to interpretation of results and to distinguish normal from disease. In this review, we present normal reference values for morphological and functional CMR parameters of the cardiovascular system based on the peer-reviewed literature and current CMR techniques and sequences.


Assuntos
Aorta/fisiologia , Imageamento por Ressonância Magnética , Função Ventricular Esquerda , Função Ventricular Direita , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Fatores Sexuais , Rigidez Vascular , Adulto Jovem
6.
J Cardiovasc Magn Reson ; 16: 26, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24758161

RESUMO

BACKGROUND: Cocaine is an addictive, sympathomimetic drug with potentially lethal effects. The prevalence and features of cocaine cardiotoxicity are not well known. We aimed to assess these effects using a comprehensive cardiovascular magnetic resonance (CMR) protocol in a large group of asymptomatic cocaine users. METHODS: Consecutive (n = 94, 81 males, 36.6 ±7 years), non-selected, cocaine abusers were recruited and had a medical history, examination, ECG, blood test and CMR. The CMR study included measurement of left and right ventricular (LV, RV) dimensions and ejection fraction (EF), sequences for detection of myocardial oedema and late gadolinium enhancement (LGE). Images were compared to a cohort of healthy controls. RESULTS: Years of regular cocaine use were 13.9 ± 9. When compared to the age-matched healthy cohort, the cocaine abusers had increased LV end-systolic volume, LV mass index and RV end-systolic volume, with decreased LVEF and RVEF. No subject had myocardial oedema, but 30% had myocardial LGE indicating myocardial damage. CONCLUSIONS: CMR detected cardiovascular disease in 71% of this cohort of consecutive asymptomatic cocaine abusers and mean duration of abuse was related to probability of LV systolic dysfunction.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Direita/diagnóstico , Adulto , Doenças Assintomáticas , Estudos de Casos e Controles , Meios de Contraste , Edema Cardíaco/diagnóstico , Edema Cardíaco/etiologia , Edema Cardíaco/patologia , Eletrocardiografia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/patologia , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Esquerda , Função Ventricular Direita , Adulto Jovem
7.
ESC Heart Fail ; 11(2): 1258-1262, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38115745

RESUMO

AIMS: Iron deficiency (ID) is associated with an impaired cardiac function and remodelling in heart failure (HF). Treatment with ferric carboxymaltose (FCM) has been showed recently to improve biventricular systolic function and ventricular strain parameters in patients with HF with reduced ejection fraction and ID, but there is no evidence on the benefit of FCM on the left atrium (LA). In this study, we aimed to evaluate the effect of FCM on LA longitudinal strain (LA-LS). METHODS AND RESULTS: This is a post hoc subanalysis of a double-blind, placebo-controlled, randomized clinical trial that enrolled 53 ambulatory patients with HF, left ventricular ejection fraction (LVEF) < 50%, and ID [Myocardial-IRON trial (NCT03398681)], treated with FCM or placebo. Cardiac magnetic resonance-featured tracking (CMR-FT) strain changes were evaluated before and 7 and 30 days after randomization using linear mixed regression analysis. The median age of the sample was 68 years (interquartile range: 64-76), and 20 (69%) were men. Mean ± standard deviation of LVEF was 39 ± 11%, and most (97%) were in stable New York Heart Association class II. At baseline, mean LA-LS was -8.9 ± 3.5%. At 30 days, and compared with placebo, LA-LS significantly improved in those allocated to FCM treatment arm (LA-LS = -12.0 ± 0.5 and -8.5 ± 0.6, respectively; - ∆ 3.55%, P < 0.001). CONCLUSIONS: In patients with stable HF, LVEF < 50%, and ID, treatment with FCM was associated with short-term improvements in LA-LS assessed by CMR-FT. Future works should assess the potential benefit of iron repletion on LA function.


Assuntos
Compostos Férricos , Insuficiência Cardíaca , Deficiências de Ferro , Maltose/análogos & derivados , Masculino , Humanos , Idoso , Feminino , Volume Sistólico , Função Ventricular Esquerda , Átrios do Coração
8.
Eur Heart J Cardiovasc Imaging ; 25(4): e116-e136, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38198766

RESUMO

Cardiovascular diseases (CVD) represent an important cause of mortality and morbidity in women. It is now recognized that there are sex differences regarding the prevalence and the clinical significance of the traditional cardiovascular (CV) risk factors as well as the pathology underlying a range of CVDs. Unfortunately, women have been under-represented in most CVD imaging studies and trials regarding diagnosis, prognosis, and therapeutics. There is therefore a clear need for further investigation of how CVD affects women along their life span. Multimodality CV imaging plays a key role in the diagnosis of CVD in women as well as in prognosis, decision-making, and monitoring of therapeutics and interventions. However, multimodality imaging in women requires specific consideration given the differences in CVD between the sexes. These differences relate to physiological changes that only women experience (e.g. pregnancy and menopause) as well as variation in the underlying pathophysiology of CVD and also differences in the prevalence of certain conditions such as connective tissue disorders, Takotsubo, and spontaneous coronary artery dissection, which are all more common in women. This scientific statement on CV multimodality in women, an initiative of the European Association of Cardiovascular Imaging of the European Society of Cardiology, reviews the role of multimodality CV imaging in the diagnosis, management, and risk stratification of CVD, as well as highlights important gaps in our knowledge that require further investigation.


Assuntos
Cardiologia , Doenças Cardiovasculares , Feminino , Humanos , Masculino , Doenças Cardiovasculares/epidemiologia , Imagem Multimodal , Sociedades Médicas , Fatores de Risco
9.
J Cardiovasc Magn Reson ; 15: 29, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23566426

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) steady state free precession (SSFP) cine sequences with high temporal resolution and improved post-processing can accurately measure RA dimensions. We used this technique to define ranges for normal RA volumes and dimensions normalized, when necessary, to the influence of gender, body surface area (BSA) and age, and also to define the best 2D images-derived predictors of RA enlargement. METHODS: For definition of normal ranges of RA volume we studied 120 healthy subjects (60 men, 60 women; 20 subjects per age decile from 20 to 80 years), after careful exclusion of cardiovascular abnormality. We also studied 120 patients (60 men, 60 women; age range 20 to 80 years) with a clinical indication for CMR in order to define the best 1D and 2D predictors of RA enlargement. Data were generated from SSFP cine CMR, with 3-dimensional modeling, including tracking of the atrioventricular ring motion and time-volume curves analysis. RESULTS: In the group of healthy individuals, age influenced RA 2-chamber area and transverse diameter. Gender influenced most absolute RA dimensions and volume. Interestingly, right atrial volumes did not change with age and gender when indexed to body surface area. New CMR normal ranges for RA dimensions were modeled and displayed for clinical use with normalization for BSA and gender and display of parameter variation with age. Finally, the best 2D images-derived independent predictors of RA enlargement were indexed area and indexed longitudinal diameter in the 2-chamber view. CONCLUSION: Reference RA dimensions and predictors of RA enlargement are provided using state-of-the-art CMR techniques.


Assuntos
Cardiopatias/diagnóstico , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Superfície Corporal , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Átrios do Coração/patologia , Cardiopatias/patologia , Humanos , Modelos Lineares , Modelos Logísticos , Imagem Cinética por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Variações Dependentes do Observador , Razão de Chances , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Fatores Sexuais , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-38083249

RESUMO

Contrast-enhanced magnetic resonance (MR) breast imaging represents a tool with great potential for the detection, evaluation and diagnosis of breast cancer (BC). Due to its high sensitivity and in combination with medical imaging biomarkers, it can overcome setbacks and limitations manifested in other diagnostic modalities such as mammography or ultrasound. In order to aid and assist clinicians in the diagnosis of BC, a methodology based on the extraction of 2D texture and 3D shape features in MR images is proposed. To categorize breast tumor malignancy, we considered its location in the coronal plane, divided into 4 quadrants (UOQ, UIQ, LOQ and LOQ), and the tumor type according to its genetic information (positive HER2 and Luminal B with negative HER2). In this regard, six different studies were conducted: one per feature type (texture and shape), as well as the combination of both features (texture + shape) for each of the two covariables (tumor type and location in the coronal plane). A dataset of 43 BC patients were considered. A radiomics approach was implemented extracting 43 texture and 17 shape features and using to train 5 different predictive models (Linear SVM, Gaussian SVM, Bagged Tree, KNN and Naïve Bayes). The highest precision result for the tumor type study (74.04% in terms of AUC) was obtained with 43 texture features. Whereas for the quadrant localization study, the highest precision result (67.99% AUC) was obtained as a combination of 3 textures and shape features. Both results were achieved with the SVM with Linear Kernel classification model.Clinical Relevance- This work emphasizes the use of quantitative biomarkers as texture and shape features in combination with machine learning techniques to aid in breast tumor malignancy diagnosis on MR imaging. Moreover, considering the location of the tumor in the coronal plane and its type according to its genetic information may improve the selection of appropriate treatments, survival rate, and quality of life for breast cancer patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Teorema de Bayes , Qualidade de Vida , Imageamento por Ressonância Magnética/métodos , Biomarcadores
11.
Med Sci Sports Exerc ; 55(2): 151-157, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36136597

RESUMO

PURPOSE: This study aimed to compare the prevalence of myocardial fibrosis and coronary calcification in individuals who have performed very high levels of strenuous endurance exercise (SEE; former male professional cyclists) and sex/age-matched controls. METHODS: We used a retrospective cohort study design, where cases were former finishers of ≥1 Grand Tour (Tour de France, Giro d' Italia or Vuelta a España) and controls were untrained individuals free of cardiovascular risk. All participants underwent cardiac magnetic resonance and cardiac computer tomography in the same center during years 2020-2021 to detect myocardial fibrosis (late gadolinium enhancement) and to quantify coronary calcium, respectively. RESULTS: Twenty-three cases (age, 46 ± 6 yr) and 59 controls (47 ± 7 yr) were studied. Fibrotic patches were evidenced only in the left ventricle, with a higher prevalence in cases (23% vs 2% in controls, P = 0.006). However, fibrotic tissue was nonischemic and of low extension (0.6% ± 0.4% of left ventricle mass), and no significant differences were found between cases and controls for native T1 or T2 values. No between-group differences were found for coronary calcium indicators, including Agatston or density scores. Subanalyses revealed no differences attending to whether cases were still performing regular SEE ( n = 8) or not ( n = 15) after professional retirement. CONCLUSIONS: Although former professional cyclists seemed to show a greater prevalence of myocardial fibrosis, the extension of fibrotic tissue was minimal and no alterations were found in coronary calcification indicators. While keeping in mind the low sample size of the cases' group, our results do not support evidence for major cardiac maladaptations with long-term exposure to SEE, at least in middle-age adults.


Assuntos
Cardiomiopatias , Resistência Física , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Meios de Contraste , Cálcio , Estudos Retrospectivos , Ciclismo , Gadolínio , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/epidemiologia , Cardiomiopatias/patologia , Fibrose , Miocárdio/patologia , Valor Preditivo dos Testes
12.
Med Sci Sports Exerc ; 55(11): 1945-1951, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37319411

RESUMO

PURPOSE: Concerns on whether athletes--particularly older ones--are at an increased risk of pathological aortic dilation exist, and the prevalence of aortic calcifications in these individuals is unknown. We aimed to compare the dimensions, distensibility, and prevalence of calcifications in the thoracic aorta between former male professional cyclists (cases) and sex/age-matched controls. METHODS: We used a retrospective cohort design, where cases were former finishers of at least one Grand Tour (Tour de France, Giro d' Italia or Vuelta a España) and controls were untrained individuals with no previous sports history and free of cardiovascular risk. All participants underwent magnetic resonance and computer tomography assessments for the measurement of aortic dimensions and calcifications, respectively. RESULTS: Cases showed larger ( P < 0.05) dimensions than controls for aortic annulus, sinus, and arch, as well as for ascending and descending aorta. However, none of the participants presented with pathological aortic dilation (all diameters <40 mm). A slightly higher prevalence of calcifications in the ascending aorta was observed in cases (13% vs 0% in controls, P = 0.020). Subanalyses confirmed that cases who were still competing (masters category, n = 8) had larger aortic diameters ( P < 0.05) and a greater presence of calcifications in the ascending/descending aorta (38% vs 0% for both segments, P = 0.032) than those who had become inactive ( n = 15). No between-group differences were found for aortic distensibility. CONCLUSIONS: Former professional cyclists, particularly those who are still competing after retirement, show enlarged aortic diameters (albeit without exceeding upper limits of normality). Former professional cyclists also showed a slightly higher prevalence of calcifications in the ascending aorta than controls, although aortic distensibility was not compromised. The clinical relevance of these findings should be the subject of future studies.


Assuntos
Calcinose , Esportes , Humanos , Masculino , Estudos Retrospectivos , Aorta/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Calcinose/epidemiologia
13.
J Cardiovasc Magn Reson ; 14: 28, 2012 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-22559053

RESUMO

Systemic hypertension is a highly prevalent potentially modifiable cardiovascular risk factor. Imaging plays an important role in the diagnosis of underlying causes for hypertension, in assessing cardiovascular complications of hypertension, and in understanding the pathophysiology of the disease process. Cardiovascular magnetic resonance (CMR) provides accurate and reproducible measures of ventricular volumes, mass, function and haemodynamics as well as uniquely allowing tissue characterization of diffuse and focal fibrosis. In addition, CMR is well suited for exclusion of common secondary causes for hypertension. We review the current and emerging clinical and research applications of CMR in hypertension.


Assuntos
Doenças Cardiovasculares/diagnóstico , Hipertensão/diagnóstico , Imageamento por Ressonância Magnética , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/fisiopatologia , Fibrose , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Hipertensão/epidemiologia , Hipertensão/patologia , Hipertensão/fisiopatologia , Miocárdio/patologia , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Função Ventricular
14.
J Cardiovasc Magn Reson ; 14: 50, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22839417

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) is the gold standard non-invasive method for determining left ventricular (LV) mass and volume but has not been used previously to characterise the LV remodeling response in aortic stenosis. We sought to investigate the degree and patterns of hypertrophy in aortic stenosis using CMR. METHODS: Patients with moderate or severe aortic stenosis, normal coronary arteries and no other significant valve lesions or cardiomyopathy were scanned by CMR with valve severity assessed by planimetry and velocity mapping. The extent and patterns of hypertrophy were investigated using measurements of the LV mass index, indexed LV volumes and the LV mass/volume ratio. Asymmetric forms of remodeling and hypertrophy were defined by a regional wall thickening ≥ 13 mm and >1.5-fold the thickness of the opposing myocardial segment. RESULTS: Ninety-one patients (61 ± 21 years; 57 male) with aortic stenosis (aortic valve area 0.93 ± 0.32 cm2) were recruited. The severity of aortic stenosis was unrelated to the degree (r2=0.012, P=0.43) and pattern (P=0.22) of hypertrophy. By univariate analysis, only male sex demonstrated an association with LV mass index (P=0.02). Six patterns of LV adaption were observed: normal ventricular geometry (n=11), concentric remodeling (n=11), asymmetric remodeling (n=11), concentric hypertrophy (n=34), asymmetric hypertrophy (n=14) and LV decompensation (n=10). Asymmetric patterns displayed considerable overlap in appearances (wall thickness 17 ± 2mm) with hypertrophic cardiomyopathy. CONCLUSIONS: We have demonstrated that in patients with moderate and severe aortic stenosis, the pattern of LV adaption and degree of hypertrophy do not closely correlate with the severity of valve narrowing and that asymmetric patterns of wall thickening are common.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Cardiomiopatia Hipertrófica/diagnóstico , Hipertrofia Ventricular Esquerda/diagnóstico , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular Esquerda , Remodelação Ventricular , Idoso , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/fisiopatologia , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/fisiopatologia , Diagnóstico Diferencial , Feminino , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 493-496, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086525

RESUMO

Osteoarthritis is one of the most disabling diseases in developed countries. Its etiology is not firmly established, and the diagnosis is made by observing radiographs, assigning a degree of severity based on the information displayed. For this reason, the diagnosis is usually late and determined by the subjectivity of the doctor, which implies a restriction of the treatment. Magnetic resonance imaging (MRI) has allowed us to see in greater detail the alterations produced in soft joint structures. In this work, biomarkers for an early diagnosis of knee osteoarthritis have been developed by means of textures analysis on MRI. For this purpose, 50 subjects underwent T1-weighted MR image acquisitions: 25 controls and 25 diagnosed with knee osteoarthritis between grades I and III. Six regions were segmented on these images, corresponding to the femorotibial cartilage, femoral condyles, and tibial plateau. 43 textures were extracted for each region of interest (ROI) employing 5 statistical methods and 5 different predictive models were trained and compared. In addition, a study of the thickness of the cartilage was carried out to make a comparison with the texture analysis. The best result has been obtained using a K-nearest neighbor model with the combination of 33 textures (maximum value of AUC = 0.7684). Furthermore, in the analysis of the cartilage thickness, no statistically significant differences were found. Finally, it is concluded that the texture analysis has great potential for the diagnosis of knee osteoarthritis. Clinical Relevance - The current study establishes a methodology for an early diagnosis of knee osteoarthritis by means of MRI-based texture analysis, in a fast and objective manner.


Assuntos
Osteoartrite do Joelho , Diagnóstico Precoce , Humanos , Articulação do Joelho , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico por imagem , Tíbia
17.
Comput Med Imaging Graph ; 99: 102085, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35689982

RESUMO

The correct assessment and characterization of heart anatomy and functionality is usually done through inspection of magnetic resonance image cine sequences. In the clinical setting it is especially important to determine the state of the left ventricle. This requires the measurement of its volume in the end-diastolic and end-systolic frames within the sequence trough segmentation methods. However, the first step required for this analysis before any segmentation is the detection of the end-systolic and end-diastolic frames within the image acquisition. In this work we present a fully convolutional neural network that makes use of dilated convolutions to encode and process the temporal information of the sequences in contrast to the more widespread use of recurrent networks that are usually employed for problems involving temporal information. We trained the network in two different settings employing different loss functions to train the network: the classical weighted cross-entropy, and the weighted Dice loss. We had access to a database comprising a total of 397 cases. Out of this dataset we used 98 cases as test set to validate our network performance. The final classification on the test set yielded a mean frame distance of 0 for the end-diastolic frame (i.e.: the selected frame was the correct one in all images of the test set) and 1.242 (relative frame distance of 0.036) for the end-systolic frame employing the optimum setting, which involved training the neural network with the Dice loss. Our neural network is capable of classifying each frame and enables the detection of the end-systolic and end-diastolic frames in short axis cine MRI sequences with high accuracy.


Assuntos
Imagem Cinética por Ressonância Magnética , Redes Neurais de Computação , Diástole , Coração , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos , Sístole
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2084-2087, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086174

RESUMO

The number of studies in the medical field that uses machine learning and deep learning techniques has been increasing in the last years. However, these techniques require a huge amount of data that can be difficult and expensive to obtain. This specially happens with cardiac magnetic resonance (MR) images. One solution to the problem is raise the dataset size by generating synthetic data. Convolutional Variational Autoencoder (CVAe) is a deep learning technique which allows to generate synthetic images, but sometimes the synthetic images can be slightly blurred. We propose the combination of the CVAe technique combined with Style Transfer technique to generate synthetic realistic cardiac MR images. Clinical Relevance-The current work presents a tool to increase in a simple easy and fast way the cardiac magnetic resonance images dataset with which perform machine learning and deep learning studies.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética , Coração/diagnóstico por imagem , Aprendizado de Máquina
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 1436-1439, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086478

RESUMO

Prostate cancer is one of the most common cancers in men, with symptoms that may be confused with those caused by benign prostatic hyperplasia. One of the key aspects of treating prostate cancer is its early detection, increasing life expectancy and improving the quality of life of those patients. However, the tests performed are often invasive, resulting in a biopsy. A non-invasive alternative is the magnetic resonance imaging (MRI)-based PI-RADS v2 classification. The aim of this work was to find objective biomarkers that allow the PI-RADS classification of prostate lesions using a radiomics approach on Multiparametric MRI. A total of 90 subjects were analyzed. From each segmented lesion, 609 different texture features were extracted using five different statistical methods. Two feature selection methods and eight multiclass predictive models were evaluated. This was a multiclass study in which the best AUC result was 0.7442 ± 0.0880, achieved with the Naïve Bayes model using a subset of 120 features. Valuable results were also obtained using the Random Forests model, obtaining an AUC of 0.7394 ± 0.0965 with a lower number of features (52). Clinical Relevance- The current study establishes a methodology for classifying prostate cancer and supporting clinical decision-making in a fast and efficient manner and avoiding additional invasive procedures using MRI.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Teorema de Bayes , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Qualidade de Vida
20.
JACC Cardiovasc Imaging ; 15(12): 2127-2138, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34922874

RESUMO

Over the past 2 decades, cardiac magnetic resonance (CMR) has become an essential component of cardiovascular clinical care and contributed to imaging-guided diagnosis and management of coronary artery disease, cardiomyopathy, congenital heart disease, cardio-oncology, valvular, and vascular disease, amongst others. The widespread availability, safety, and capability of CMR to provide corresponding anatomical, physiological, and functional data in 1 imaging session can improve the design and conduct of clinical trials through both a reduction of sample size and provision of important mechanistic data that may augment clinical trial findings. Moreover, prospective imaging-guided strategies using CMR can enhance safety, efficacy, and cost-effectiveness of cardiovascular pathways in clinical practice around the world. As the future of large-scale clinical trial design evolves to integrate personalized medicine, cost-effectiveness, and mechanistic insights of novel therapies, the integration of CMR will continue to play a critical role. In this document, the attributes, limitations, and challenges of CMR's integration into the future design and conduct of clinical trials will also be covered, and recommendations for trialists will be explored. Several prominent examples of clinical trials that test the efficacy of CMR-imaging guided pathways will also be discussed.


Assuntos
Estudos Prospectivos , Humanos , Valor Preditivo dos Testes , Espectroscopia de Ressonância Magnética
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