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1.
Cardiovasc Diabetol ; 15: 34, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26892325

RESUMO

BACKGROUND: Diabetes mellitus (DM) is estimated to become the 7th leading cause of death by 2030. Right ventricular dysfunction (RVD) complicating ST elevation myocardial infarction (STEMI) is independently associated with a higher mortality; however the relationship between DM and RVD is currently unknown. The purpose of this study was to determine whether DM is an independent predictor for the presence of right ventricular dysfunction (RVD) post STEMI. METHODS: 106 patients post primary PCI for STEMI were enrolled in the study. Cardiac MRI was performed within 48-72 h after admission in order to assess ventricular function. Statistical analysis consisted initially of descriptive statistics including Chi square, Fisher's exact, or the Wilcoxon rank sum as appropriate. Subsequently, logistic regression analysis was performed to determine independent predictors of RVD. RESULTS: The median age in the study was 58 years (IQR 53, 67). 30 % of the patients had diabetes. Of 99 patients for which RV data was available, 40 had RVD and 59 did not. Patients with DM were significantly more likely to have RVD when compared to those without diabetes (45 vs 22 %, p = 0.03). There was no significant difference in age, hypertension, smoking status, dyslipidemia, serum creatinine or peak CK levels between the two groups. After adjusting for other factors, presence of DM remained an independent predictor for the presence of RV dysfunction (OR 2.78, 95 % CI 1.12, 6.87, p = 0.03). Amongst diabetic patients, those with HbA1C ≥ 7 % had greater odds of having RVD vs those with HbA1C < 7 % (OR 5.58 (1.20, 25.78), p = 0.02). CONCLUSIONS: The presence of DM conferred an approximately threefold greater odds of being associated with RVD post STEMI. No other major cardiovascular risk factors were independently associated with the presence of RVD.


Assuntos
Complicações do Diabetes/etiologia , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea/efeitos adversos , Disfunção Ventricular Direita/etiologia , Função Ventricular Direita , Idoso , Distribuição de Qui-Quadrado , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/fisiopatologia , Feminino , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Razão de Chances , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/fisiopatologia
2.
BMC Cardiovasc Disord ; 16(1): 198, 2016 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-27741939

RESUMO

BACKGROUND: Infarct heterogeneity, as assessed by determination of the peri-infarct zone (PIZ) by cardiac magnetic resonance imaging, has been shown to be an independent predictor for the development of cardiac arrhythmias and mortality post myocardial infarction (MI). The temporal evolution of the PIZ post MI is currently unknown. Thus, the main objective of our study was to describe the temporal evolution of the PIZ over a 6 month time period in contemporarily managed ST elevation myocardial infarction (STEMI) patients. Further, given the poor prognosis associated with microvascular obstruction (MVO) post STEMI, we sought to compare the temporal evolution of the PIZ in patients with and without MVO. We hypothesized that patients with MVO would show a relative persistence of PIZ over time when compared to those without MVO. METHODS: Twenty-one patients post primary percutaneous coronary intervention were enrolled and treated with evidence based therapy. Each patient had three cardiac MRI scans at 48 h, 3 weeks and 6 months post infarction. Repeated Measures Analysis of Variance (ANOVA) was used to assess the evolution of core infarct size and peri-infarct zone size across the three time frames. RESULTS: The patients in this study were predominantly male, with ~40 % LAD territory infarction and a mean LVEF of 46 ± 7 %. Core infarct size and PIZ size both decreased significantly across the three time frames. The presence of microvascular obstruction (MVO), a known adverse prognostic factor, influenced PIZ size. Both patients with and without MVO had a significant reduction in core infarct size over time. Patients with MVO did not have a significant change in PIZ size over time (11.9 ± 6.8 %, 12.2 ± 7.5 %, 10.7 ± 6.6 % p = 0.77). In contrast, non-MVO patients did have a significant decrease in PIZ size over time (7.0 ± 5.5 %, 7.1 ± 6.5 %, 2.7 ± 2.6 %, p = 0.01). CONCLUSIONS: Peri-infarct zone size, like core infarct size, varies depending upon the timing of measurement. Patients with MVO displayed a persistence of the PIZ over time.


Assuntos
Circulação Coronária/fisiologia , Vasos Coronários/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Miocárdio/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Vasos Coronários/fisiopatologia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Índice de Gravidade de Doença , Fatores de Tempo
3.
J Heart Valve Dis ; 25(4): 417-423, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-28009943

RESUMO

BACKGROUND AND AIM OF THE STUDY: A major drawback of the transcatheter aortic valve replacement (TAVR) procedure using the self-expandable Medtronic CoreValve (MCV) prosthesis is the high incidence of conduction disturbances and the need for postprocedural permanent pacemaker (PPM) implantation. The depth of prosthesis implantation may be an important contributing factor. The study aim was to determine the relationship between angiographic measurements of the MCV prosthesis depth and the occurrence of new conduction disturbances and need for PPM after TAVR. METHODS: A retrospective analysis was conducted of 157 consecutive patients who had undergone TAVR procedures with the MCV between 2009 and 2013. Patients with pre-existing pacemakers (n = 27) were excluded. Prosthesis depth was defined as the angiographic distance from the lowest part of the prosthesis to the base of the non-coronary cusp (NCcD) and the base of the left coronary cusp (LCcD). RESULTS: A 26 mm MCV was implanted in 50% of patients, and a 29 mm MCV in 38%. The rate of new ≥2nd degree atrioventricular block (AVB) after TAVR was 5%, and the incidence of new left ventricular bundle branch block (LBBB) was 23%. PPMs were implanted in 13 patients (10%) within 30 days after the procedure. Freedom from new ≥2nd degree AVB, LBBB and the need for PPM after TAVR was significantly higher among patients with NCcD <6 mm or LCcD <8 mm (90% and 89%, respectively) compared to patients with NCcD ≥6 mm or LCcD ≥8 mm (53% and 54%, respectively) (p <0.0001). CONCLUSIONS: Prosthesis depth, measured relative to either the NCcD or LCcD, strongly predicted the occurrence of conduction disturbances and the need for PPM following TAVR with the MCV prosthesis.


Assuntos
Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Complicações Pós-Operatórias/diagnóstico por imagem , Substituição da Valva Aórtica Transcateter/instrumentação , Idoso de 80 Anos ou mais , Angiografia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/terapia , Bloqueio de Ramo/etiologia , Bloqueio de Ramo/terapia , Estimulação Cardíaca Artificial , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Substituição da Valva Aórtica Transcateter/efeitos adversos
4.
Circulation ; 130(23): 2031-9, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25239440

RESUMO

BACKGROUND: Patients with chronic granulomatous disease (CGD) experience immunodeficiency because of defects in the phagocyte NADPH oxidase and the concomitant reduction in reactive oxygen intermediates. This may result in a reduction in atherosclerotic injury. METHODS AND RESULTS: We prospectively assessed the prevalence of cardiovascular risk factors, biomarkers of inflammation and neutrophil activation, and the presence of magnetic resonance imaging and computed tomography quantified subclinical atherosclerosis in the carotid and coronary arteries of 41 patients with CGD and 25 healthy controls in the same age range. Univariable and multivariable associations among risk factors, inflammatory markers, and atherosclerosis burden were assessed. Patients with CGD had significant elevations in traditional risk factors and inflammatory markers compared with control subjects, including hypertension, high-sensitivity C-reactive protein, oxidized low-density lipoprotein, and low high-density lipoprotein. Despite this, patients with CGD had a 22% lower internal carotid artery wall volume compared with control subjects (361.3±76.4 mm(3) versus 463.5±104.7 mm(3); P<0.001). This difference was comparable in p47(phox)- and gp91(phox)-deficient subtypes of CGD and independent of risk factors in multivariate regression analysis. In contrast, the prevalence of coronary arterial calcification was similar between patients with CGD and control subjects (14.6%, CGD; 6.3%, controls; P=0.39). CONCLUSIONS: The observation by magnetic resonance imaging and computerized tomography of reduced carotid but not coronary artery atherosclerosis in patients with CGD despite the high prevalence of traditional risk factors raises questions about the role of NADPH oxidase in the pathogenesis of clinically significant atherosclerosis. Additional high-resolution studies in multiple vascular beds are required to address the therapeutic potential of NADPH oxidase inhibition in cardiovascular diseases. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01063309.


Assuntos
Doenças das Artérias Carótidas , Doença da Artéria Coronariana , Doença Granulomatosa Crônica , Glicoproteínas de Membrana/imunologia , NADPH Oxidases/deficiência , Adulto , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/imunologia , Doenças das Artérias Carótidas/patologia , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/imunologia , Doença da Artéria Coronariana/patologia , Estudos Transversais , Feminino , Doença Granulomatosa Crônica/epidemiologia , Doença Granulomatosa Crônica/imunologia , Doença Granulomatosa Crônica/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , NADPH Oxidase 2 , NADPH Oxidases/genética , NADPH Oxidases/imunologia , NADPH Oxidases/metabolismo , Fagócitos/imunologia , Prevalência , Fatores de Risco , Calcificação Vascular/epidemiologia , Calcificação Vascular/imunologia , Calcificação Vascular/patologia , Adulto Jovem
5.
Radiology ; 271(2): 381-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24592924

RESUMO

PURPOSE: To determine if carotid plaque morphology and composition with magnetic resonance (MR) imaging can be used to identify asymptomatic subjects at risk for cardiovascular events. MATERIALS AND METHODS: Institutional review boards at each site approved the study, and all sites were Health Insurance Portability and Accountability Act (HIPAA) compliant. A total of 946 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) were evaluated with MR imaging and ultrasonography (US). MR imaging was used to define carotid plaque composition and remodeling index (wall area divided by the sum of wall area and lumen area), while US was used to assess carotid wall thickness. Incident cardiovascular events, including myocardial infarction, resuscitated cardiac arrest, angina, stroke, and death, were ascertained for an average of 5.5 years. Multivariable Cox proportional hazards models, C statistics, and net reclassification improvement (NRI) for event prediction were determined. RESULTS: Cardiovascular events occurred in 59 (6%) of participants. Carotid IMT as well as MR imaging remodeling index, lipid core, and calcium in the internal carotid artery were significant predictors of events in univariate analysis (P < .001 for all). For traditional risk factors, the C statistic for event prediction was 0.696. For MR imaging remodeling index and lipid core, the C statistic was 0.734 and the NRI was 7.4% and 15.8% for participants with and those without cardiovascular events, respectively (P = .02). The NRI for US IMT in addition to traditional risk factors was not significant. CONCLUSION: The identification of vulnerable plaque characteristics with MR imaging aids in cardiovascular disease prediction and improves the reclassification of baseline cardiovascular risk.


Assuntos
Estenose das Carótidas/etnologia , Estenose das Carótidas/epidemiologia , Doença da Artéria Coronariana/etnologia , Doença da Artéria Coronariana/epidemiologia , Imageamento por Ressonância Magnética/métodos , Placa Aterosclerótica/etnologia , Placa Aterosclerótica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Espessura Intima-Media Carotídea , Meios de Contraste , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
6.
J Magn Reson Imaging ; 40(3): 709-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24470317

RESUMO

PURPOSE: To characterize the evolution of right ventricular (RV) function post-myocardial infarction (MI), to describe the culprit vessel involved with RV injury and to assess the concordance between RV injury on magnetic resonance imaging (MRI) and RV infarct on electrocardiogram (EKG). MATERIALS AND METHODS: Thirty-one patients underwent cardiovascular magnetic resonance (CMR) examinations at three time frames post-ST elevation MI (STEMI). RESULTS: Of those with an initial normal scan, RV function did not significantly change over time (60.6 ± 6.3, 57.8 ± 6.0, 55.4 ± 5.7, P > 0.05). However, in those whose RVEF (RV ejection fraction) was initially low, it significantly increased from the first scan to the third scan (46.2 ± 3.6, 50 ± 6.6, 51.3 ± 5.2, P < 0.01). Post-hoc testing revealed a significant difference between the 48-hour and the 6-month scan, and between the 48-hour and the 3-week scan; however, there was no significant difference between the 3-week and 6-month scans. Interestingly, 23% of patients with low RVEF at baseline had the left anterior descending (LAD) as the culprit vessel. Only 15% of the low RVEF at baseline group were classified as having an RVMI by EKG criteria. CONCLUSIONS: The optimal timepoint to assess for RV injury via CMR may be 3 weeks post-acute MI. Standard EKG criteria may underestimate RV injury when compared to CMR.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Disfunção Ventricular Direita/fisiopatologia , Meios de Contraste , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos , Intervenção Coronária Percutânea/métodos , Prognóstico , Estudos Prospectivos
7.
Can Assoc Radiol J ; 65(3): 218-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24650872

RESUMO

PURPOSE: To assess ultrasound intrascan variability and the potential error rate of serial ultrasounds in the diagnosis of deep venous thrombosis in children. METHODS: A retrospective cohort review of imaging results of children having at least 3 serial ultrasound examinations of the same region within a 2-month period. The results were interpreted as either (1) inadequately visualized or (2) the absence or presence of deep venous thrombosis, and were categorized by location. Serial imaging findings then were further categorized based on results and clinical information. RESULTS: Sixty-four patients and 157 vessel segments were included in the study. Deep venous thrombosis was documented in 58 patients. Concordant results were observed in 26 patients (40.1%), clot resolution in 17 patients (26.6%), clot formation in 12 patients (18.8%), and discordant results in 9 patients (14%). Twenty-one of 64 patients (32.8%) had at least 1 vessel inadequately imaged. CONCLUSIONS: The inconsistency of serial ultrasound results in up to 25% of patients calls attention to the potential inaccuracy of ultrasound for diagnosis and follow-up of deep venous thrombosis in children. The high proportion of patients with at least 1 inadequately visualized vessel also highlights the limitation of ultrasound in the diagnosis of pediatric deep venous thrombosis.


Assuntos
Trombose Venosa/diagnóstico por imagem , Adolescente , Alberta/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ultrassonografia , Trombose Venosa/epidemiologia
9.
ACS Appl Nano Mater ; 6(17): 15385-15396, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37706067

RESUMO

Characterizing complex biofluids using surface-enhanced Raman spectroscopy (SERS) coupled with machine learning (ML) has been proposed as a powerful tool for point-of-care detection of clinical disease. ML is well-suited to categorizing otherwise uninterpretable, patient-derived SERS spectra that contain a multitude of low concentration, disease-specific molecular biomarkers among a dense spectral background of biological molecules. However, ML can generate false, non-generalizable models when data sets used for model training are inadequate. It is thus critical to determine how different SERS experimental methodologies and workflow parameters can potentially impact ML disease classification of clinical samples. In this study, a label-free, broadband, Ag nanoparticle-based SERS platform was coupled with ML to assess simulated clinical samples for cardiovascular disease (CVD), containing randomized combinations of five key CVD biomarkers at clinically relevant concentrations in serum. Raman spectra obtained at 532, 633, and 785 nm from up to 300 unique samples were classified into physiological and pathological categories using two standard ML models. Label-free SERS and ML could correctly classify randomized CVD samples with high accuracies of up to 90.0% at 532 nm using as few as 200 training samples. Spectra obtained at 532 nm produced the highest accuracies with no significant increase achieved using multiwavelength SERS. Sample preparation and measurement methodologies (e.g., different SERS substrate lots, sample volumes, sample sizes, and known variations in randomization and experimental handling) were shown to strongly influence the ML classification and could artificially increase classification accuracies by as much as 27%. This detailed investigation into the proper application of ML techniques for CVD classification can lead to improved data set acquisition required for the SERS community, such that ML on labeled and robust SERS data sets can be practically applied for future point-of-care testing in patients.

10.
Radiology ; 264(3): 876-83, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22771879

RESUMO

PURPOSE: To develop a cardiac computed tomographic (CT) method with which to determine extracellular volume (ECV) fraction, with cardiac magnetic resonance (MR) imaging as the reference standard. MATERIALS AND METHODS: Study participants provided written informed consent to participate in this institutional review board-approved study. ECV was measured in healthy subjects and patients with heart failure by using cardiac CT and cardiac MR imaging. Paired Student t test, linear regression analysis, and Pearson correlation analysis were used to determine the relationship between cardiac CT and MR imaging ECV values and clinical parameters. RESULTS: Twenty-four subjects were studied. There was good correlation between myocardial ECV measured at cardiac MR imaging and that measured at cardiac CT (r = 0.82, P < .001). As expected, ECV was higher in patients with heart failure than in healthy control subjects for both cardiac CT and cardiac MR imaging (P = .03, respectively). For both cardiac MR imaging and cardiac CT, ECV was positively associated with end diastolic and end systolic volume and inversely related to ejection fraction (P < .05 for all). Mean radiation dose was 1.98 mSv ± 0.16 (standard deviation) for each cardiac CT acquisition. CONCLUSION: ECV at cardiac CT and that at cardiac MR imaging showed good correlation, suggesting the potential for myocardial tissue characterization with cardiac CT.


Assuntos
Fibrose Endomiocárdica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem de Sincronização Cardíaca , Meios de Contraste , Feminino , Fibrose , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doses de Radiação
11.
J Cardiovasc Magn Reson ; 14: 27, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22548832

RESUMO

BACKGROUND: Myocardial T1 relaxation time (T1 time) and extracellular volume fraction (ECV) are altered in the presence of myocardial fibrosis. The purpose of this study was to evaluate acquisition factors that may result in variation of measured T1 time and ECV including magnetic field strength, cardiac phase and myocardial region. METHODS: 31 study subjects were enrolled and underwent one cardiovascular MR exam at 1.5 T and two exams at 3 T, each on separate days. A Modified Look-Locker Inversion Recovery (MOLLI) sequence was acquired before and 5, 10, 12, 20, 25 and 30 min after administration of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist) at 1.5 T (exam 1). For exam 2, MOLLI sequences were acquired at 3 T both during diastole and systole, before and after administration of Gd-DTPA (0.15 mmol/kg Magnevist).Exam 3 was identical to exam 2 except gadobenate dimeglumine was administered (Gd-BOPTA; 0.1 mmol/kg Multihance). T1 times were measured in myocardium and blood. ECV was calculated by (ΔR1myocardium/ΔR1blood)*(1-hematocrit). RESULTS: Before gadolinium, T1 times of myocardium and blood were significantly greater at 3 T versus 1.5 T (28% and 31% greater, respectively, p < 0.001); after gadolinium, 3 T values remained greater than those at 1.5 T (14% and 12% greater for myocardium and blood at 3 T with Gd-DTPA, respectively, p < 0.0001 and 18% and 15% greater at 3 T with Gd-BOPTA, respectively, p < 0.0001). However, ECV did not vary significantly with field strength when using the same contrast agent at equimolar dose (p = 0.2). Myocardial T1 time was 1% shorter at systole compared to diastole pre-contrast and 2% shorter at diastole compared to systole post-contrast (p < 0.01). ECV values were greater during diastole compared to systole on average by 0.01 (p < 0.01 to p < 0.0001). ECV was significantly higher for the septum compared to the non-septal myocardium for all three exams (p < 0.0001-0.01) with mean absolute differences of 0.01, 0.004, and 0.07, respectively, for exams 1, 2 and 3. CONCLUSION: ECV is similar at field strengths of 1.5 T and 3 T. Due to minor variations in T1 time and ECV during the cardiac cycle and in different myocardial regions, T1 measurements should be obtained at the same cardiac phase and myocardial region in order to obtain consistent results.


Assuntos
Cardiopatias/diagnóstico , Aumento da Imagem/métodos , Imagem Cinética por Ressonância Magnética/métodos , Contração Miocárdica/fisiologia , Miocárdio/patologia , Adulto , Meios de Contraste , Feminino , Fibrose , Gadolínio , Gadolínio DTPA , Cardiopatias/fisiopatologia , Humanos , Masculino , Meglumina/análogos & derivados , Compostos Organometálicos , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Adulto Jovem
12.
J Cardiovasc Magn Reson ; 14: 26, 2012 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-22540153

RESUMO

PURPOSE: Myocardial T1 relaxation time (T1 time) and extracellular volume fraction (ECV) are altered in patients with diffuse myocardial fibrosis. The purpose of this study was to perform an intra-individual assessment of normal T1 time and ECV for two different contrast agents. METHODS: A modified Look-Locker Inversion Recovery (MOLLI) sequence was acquired at 3 T in 24 healthy subjects (8 men; 28 ± 6 years) at mid-ventricular short axis pre-contrast and every 5 min between 5-45 min after injection of a bolus of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist®) (exam 1) and 0.1 mmol/kg gadobenate dimeglumine (Gd-BOPTA; Multihance®) (exam 2) during two separate scanning sessions. T1 times were measured in myocardium and blood on generated T1 maps. ECVs were calculated as ΔR1 myocardium/ΔR1 blood*1-hematocrit. RESULTS: Mean pre-contrast T1 relaxation times for myocardium and blood were similar for both the first and second CMR exam (p > 0.5). Overall mean post-contrast myocardial T1 time was 15 ± 2 ms (2.5 ± 0.7%) shorter for Gd-DTPA at 0.15 mmol/kg compared to Gd-BOPTA at 0.1 mmol/kg (p < 0.01) while there was no significant difference for T1 time of blood pool (p > 0.05). Between 5 and 45 minutes after contrast injection, mean ECV values increased linearly with time for both contrast agents from 0.27 ± 0.03 to 0.30 ± 0.03 (p < 0.0001). Mean ECV values were slightly higher (by 0.01, p < 0.05) for Gd-DTPA compared to Gd-BOPTA. Inter-individual variation of ECV was higher (CV 8.7% [exam 1, Gd-DTPA] and 9.4% [exam 2, Gd-BOPTA], respectively) compared to variation of pre-contrast myocardial T1 relaxation time (CV 4.5% [exam 1] and 3.0% [exam 2], respectively). ECV with Gd-DTPA was highly correlated to ECV by Gd-BOPTA (r = 0.803; p < 0.0001). CONCLUSION: In comparison to pre-contrast myocardial T1 relaxation time, variation in ECV values of normal subjects is larger. However, absolute differences in ECV between Gd-DTPA and Gd-BOPTA were small and rank correlation was high. There is a small and linear increase in ECV over time, therefore ideally images should be acquired at the same delay after contrast injection.


Assuntos
Meios de Contraste , Gadolínio DTPA , Cardiopatias/diagnóstico , Imageamento por Ressonância Magnética , Meglumina/análogos & derivados , Miocárdio/patologia , Compostos Organometálicos , Adulto , Fibrose , Cardiopatias/patologia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Maryland , Variações Dependentes do Observador , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
13.
Sci Rep ; 12(1): 21130, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476715

RESUMO

Ingestible robotic capsules with locomotion capabilities and on-board sampling mechanism have great potential for non-invasive diagnostic and interventional use in the gastrointestinal tract. Real-time tracking of capsule location and operational state is necessary for clinical application, yet remains a significant challenge. To this end, we propose an approach that can simultaneously determine the mechanism state and in-plane 2D pose of millimeter capsule robots in an anatomically representative environment using ultrasound imaging. Our work proposes an attention-based hierarchical deep learning approach and adapts the success of transfer learning towards solving the multi-task tracking problem with limited dataset. To train the neural networks, we generate a representative dataset of a robotic capsule within ex-vivo porcine stomachs. Experimental results show that the accuracy of capsule state classification is 97%, and the mean estimation errors for orientation and centroid position are 2.0 degrees and 0.24 mm (1.7% of the capsule's body length) on the hold-out test set. Accurate detection of the capsule while manipulated by an external magnet in a porcine stomach and colon is also demonstrated. The results suggest our proposed method has the potential for advancing the wireless capsule-based technologies by providing accurate detection of capsule robots in clinical scenarios.


Assuntos
Aprendizado Profundo , Robótica , Animais , Suínos , Ultrassonografia
14.
Nephrol Dial Transplant ; 26(9): 3038-45, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21321005

RESUMO

BACKGROUND: Clinical- and histopathology-based scores are limited predictors of allograft outcome. In addition, more objective markers of early transplant function are needed to identify and validate biomarkers and predictive scores. We evaluated existing scores and transcriptome biomarkers of kidney injury as predictors of early transplant function measured by renal scan. METHODS: Clinical, histopathologic and transcriptome data were collected in 143 consecutive kidney transplant recipients. A post-operative renal scan was performed within 48 h. Prediction scores for early outcomes were calculated. RESULTS: Patients were stratified into three groups by renal scan: normal, mild-to-moderate or severe dysfunction. Kidneys with severe dysfunction were more often from deceased donors (P < 0.001), had greater HLA antigen mismatches (P < 0.001), were transplanted into older recipients (P = 0.040), had lower urine output during the first 8 h (P < 0.001), higher Day 7 serum creatinine (P < 0.001) and higher incidence of delayed graft function (P < 0.001). Clinical- and pathology-based scores did not discriminate between scan groups. In contrast, the overall transcriptome (P < 0.001) and transcripts of preselected acute kidney injury (AKI) genes were significantly different between the groups, with kidney injury molecule 1 (P = 0.001) and neutrophil gelatinase-associated lipocalin (P = 0.002) being most highly expressed and genes associated with glutathione metabolism (GSTA1, 3 and 4) most down-regulated in kidneys with subsequent severe dysfunction. CONCLUSIONS: Renal scans reflect early transplant function and allow for a more objective assessment of scores predicting early outcome and for identification of biomarkers. The study shows that transcript levels of AKI genes correlate better with renal scans than clinical- or histopathology-based scores.


Assuntos
Injúria Renal Aguda/diagnóstico , Biomarcadores/metabolismo , Função Retardada do Enxerto/diagnóstico , Rejeição de Enxerto/diagnóstico , Transplante de Rim , Rim/fisiopatologia , Imageamento por Ressonância Magnética , Injúria Renal Aguda/etiologia , Adulto , Biomarcadores/análise , Função Retardada do Enxerto/etiologia , Feminino , Seguimentos , Perfilação da Expressão Gênica , Rejeição de Enxerto/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/genética , Taxa de Sobrevida , Transplante Homólogo
15.
J Med Case Rep ; 10: 153, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27268217

RESUMO

BACKGROUND: Spontaneous coronary artery dissection is a rare cause of myocardial infarction that must always be considered on a clinician's differential diagnosis, particularly in patients <50-years old with a paucity of typical vascular risk factors. CASE PRESENTATION: We describe a case of a 33-year-old white woman, 3 weeks postpartum, presenting with retrosternal chest and back pain, neck pain and stiffness, and intermittent headaches. Subsequent workup revealed concurrent spontaneous dissections in three separate medium-sized arterial beds. CONCLUSIONS: She was successfully managed in a conservative fashion, highlighting that percutaneous or surgical revascularization can often be foregone in favor of conservative medical therapy.


Assuntos
Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/fisiopatologia , Vasos Coronários/fisiopatologia , Artérias Mesentéricas/fisiopatologia , Infarto do Miocárdio/etiologia , Transtornos Puerperais/fisiopatologia , Doenças Vasculares/congênito , Adulto , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Diagnóstico Diferencial , Eletrocardiografia , Feminino , Humanos , Artérias Mesentéricas/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Período Pós-Parto , Transtornos Puerperais/diagnóstico por imagem , Doenças Vasculares/complicações , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/fisiopatologia , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiopatologia
16.
Int J Cardiovasc Imaging ; 32(1): 83-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26293362

RESUMO

Atherosclerosis is the ubiquitous underling pathological process that manifests in heart attack and stroke, cumulating in the death of one in three North American adults. High-resolution magnetic resonance imaging (MRI) is able to delineate atherosclerotic plaque components and total plaque burden within the carotid arteries. Using dedicated hardware, high resolution images can be obtained. Combining pre- and post-contrast T1, T2, proton-density, and magnetization-prepared rapid acquisition gradient echo weighted fat-saturation imaging, plaque components can be defined. Post-processing software allows for semi- and fully automated quantitative analysis. Imaging correlation with surgical specimens suggests that this technique accurately differentiates plaque features. Total plaque burden and specific plaque components such as a thin fibrous cap, large fatty or necrotic core and intraplaque hemorrhage are accepted markers of neuroischemic events. Given the systemic nature of atherosclerosis, emerging science suggests that the presence of carotid plaque is also an indicator of coronary artery plaque burden, although the preliminary data primarily involves patients with stable coronary disease. While the availability and cost-effectiveness of MRI will ultimately be important determinants of whether carotid MRI is adopted clinically in cardiovascular risk assessment, the high accuracy and reliability of this technique suggests that it has potential as an imaging biomarker of future risk.


Assuntos
Artérias Carótidas/patologia , Doenças das Artérias Carótidas/patologia , Angiografia por Ressonância Magnética , Placa Aterosclerótica , Automação , Doenças das Artérias Carótidas/terapia , Desenho de Equipamento , Fibrose , Humanos , Interpretação de Imagem Assistida por Computador , Angiografia por Ressonância Magnética/instrumentação , Angiografia por Ressonância Magnética/métodos , Necrose , Neovascularização Patológica , Valor Preditivo dos Testes , Prognóstico , Software
17.
J Clin Imaging Sci ; 5: 48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26430541

RESUMO

Blunt and penetrating cardiovascular (CV) injuries are associated with a high morbidity and mortality. Rapid detection of these injuries in trauma is critical for patient survival. The advent of multi-detector computed tomography (MDCT) has led to increased detection of CV injuries during rapid comprehensive scanning of stabilized major trauma patients. MDCT has the ability to acquire images with a higher temporal and spatial resolution, as well as the capability to create multiplanar reformats. This pictorial review illustrates several common and life-threatening traumatic CV injuries from a regional trauma center.

18.
J Am Soc Echocardiogr ; 26(5): 548-55, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23522805

RESUMO

BACKGROUND: Carotid and coronary atherosclerosis are associated with each other in imaging and autopsy studies. The aim of this study was to evaluate whether carotid artery plaque seen on carotid ultrasound can predict incident coronary artery calcification (CAC). METHODS: Agatston calcium score measurements were repeated in 5,445 participants of the Multi-Ethnic Study of Atherosclerosis (MESA; mean age, 57.9 years; 62.9% women). Internal carotid artery lesions were graded as 0%, 1% to 24%, or >25% diameter narrowing, and intima-media thickness (IMT) was measured. Plaque was present for any stenosis >0%. CAC progression was evaluated with multivariate relative risk regression for CAC scores of 0 at baseline and with multivariate linear regression for CAC score > 0, adjusting for cardiovascular risk factors, body mass index, ethnicity, and common carotid IMT. RESULTS: CAC was positive at baseline in 2,708 of 5,445 participants (49.7%) and became positive in 458 of 2,837 (16.1%) at a mean interval of 2.4 years between repeat examinations. Plaque and internal carotid artery IMT were both strongly associated with the presence of CAC. After statistical adjustment, the presence of carotid artery plaque significantly predicted incident CAC with a relative risk of 1.37 (95% confidence interval, 1.12-1.67). Incident CAC was associated with internal carotid artery IMT, with a relative risk of 1.13 (95% confidence interval, 1.03-1.25) for each 1-mm increase. Progression of CAC was also significantly associated (P < .001) with plaque and internal carotid artery IMT. CONCLUSIONS: In individuals free of cardiovascular disease, subjective and quantitative measures of carotid artery plaques by ultrasound imaging are associated with CAC incidence and progression.


Assuntos
Calcinose , Estenose das Carótidas/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/diagnóstico por imagem , Progressão da Doença , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
19.
Int J Cardiovasc Imaging ; 29(7): 1477-83, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23624959

RESUMO

Intraplaque hemorrhage (IPH), a component of late-stage complicated plaque, identified within carotid endarterectomy surgical specimens has been recently demonstrated to predict cardiovascular (CV) events. MRI is able to depict carotid IPH. We investigated the ability of carotid MR-depicted IPH (MR-IPH) to identify high-risk CV patients. From January 2008 to April 2011, 216 patients (mean age, 67.5 years; range 31-100) referred for neurovascular MRI at an academic tertiary care centre, underwent 3T carotid MRI with adjunct 3D high-spatial-resolution coronal imaging to detect MR-IPH. Five experienced neuroradiologists made a binary decision on the presence or absence of MR-IPH. Patients' charts were reviewed blindly for demographic and CV outcomes data. Of the patients with and without MR-IPH, 62.5 % (15/24) and 19.8 % (38/192) had a composite CV event (defined as a past myocardial infarction, coronary intervention (i.e., angioplasty, stenting or bypass graft) and/or peripheral vascular disease), respectively. The odds ratio (OR) of a composite CV event in the MR-IPH group was 6.75 (Bivariable analysis, 95 % CI 2.75-16.6, p < 0.0001) and 3.25 (Multivariable regression analysis, 1.14-9.37, p = 0.028). MR-IPH had the highest OR of a prior CV event compared to other variables including age, sex, hypertension and stenosis. The OR of individual CV events was also significant: MI (3.35, 95 % CI 2.11-14.2, p < 0.01), coronary stenting (26.4, 95 % CI 8.80-79.4, p < 0.01), coronary angioplasty (21, 95 % CI 4.84-91.1, p < 0.01), and PVD (3.35, 95 % CI 1.09-10.3, p < 0.05). MR-IPH is independently associated with prior CV events in patients who are evaluated for neurovascular disease. Carotid MR-IPH, employed easily in routine clinical practice, is emerging as an indicator of systemic vascular disease and may potentially be a useful surrogate marker of CV risk including in those already undergoing neurovascular imaging.


Assuntos
Artérias Carótidas/patologia , Doenças das Artérias Carótidas/diagnóstico , Hemorragia/diagnóstico , Angiografia por Ressonância Magnética , Placa Aterosclerótica , Centros Médicos Acadêmicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/instrumentação , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/patologia , Distribuição de Qui-Quadrado , Ponte de Artéria Coronária , Feminino , Hemorragia/complicações , Hemorragia/patologia , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Razão de Chances , Doenças Vasculares Periféricas/complicações , Fenótipo , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Stents , Centros de Atenção Terciária
20.
J Am Heart Assoc ; 2(2): e000087, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23568342

RESUMO

BACKGROUND: Carotid artery plaques are associated with coronary artery atherosclerotic lesions. We evaluated various ultrasound definitions of carotid artery plaque as predictors of future cardiovascular disease (CVD) and coronary heart disease (CHD) events. METHODS AND RESULTS: We studied the risk factors and ultrasound measurements of the carotid arteries at baseline of 6562 members (mean age 61.1 years; 52.6% women) of the Multi-Ethnic Study of Atherosclerosis (MESA). ICA lesions were defined subjectively as >0% or ≥25% diameter narrowing, as continuous intima-media thickness (IMT) measurements (maximum IMT or the mean of the maximum IMT of 6 images) and using a 1.5-mm IMT cut point. Multivariable Cox proportional hazards models were used to estimate hazard ratios for incident CVD, CHD, and stroke. Harrell's C-statistics, Net Reclassification Improvement, and Integrated Discrimination Improvement were used to evaluate the incremental predictive value of plaque metrics. At 7.8-year mean follow-up, all plaque metrics significantly predicted CVD events (n=515) when added to Framingham risk factors. All except 1 metric improved the prediction of CHD (by C-statistic, Net Reclassification Improvement, and Integrated Discrimination Improvement. Mean of the maximum IMT had the highest NRI (7.0%; P=0.0003) with risk ratio of 1.43/mm; 95% CI 1.26-1.63) followed by maximum IMT with an NRI of 6.8% and risk ratio of 1.27 (95% CI 1.18-1.38). CONCLUSION: Ultrasound-derived plaque metrics independently predict cardiovascular events in our cohort and improve risk prediction for CHD events when added to Framingham risk factors.


Assuntos
Estenose das Carótidas/epidemiologia , Doença das Coronárias/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/epidemiologia , Doenças Cardiovasculares/epidemiologia , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Estenose das Carótidas/diagnóstico por imagem , Estudos de Coortes , Doença das Coronárias/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade
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