Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Comput Methods Programs Biomed ; 211: 106373, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562717

RESUMO

BACKGROUND: Left and right ventricle automatic segmentation remains one of the more important tasks in computed aided diagnosis. Active contours have shown to be efficient for this task, however they often require user interaction to provide the initial position, which drives the tool substantially dependent on a prior knowledge and a manual process. METHODS: We propose to overcome this limitation with a Convolutional Neural Network (CNN) to reach the assumed target locations. This is followed by a novel multiphase active contour method based on texture that enhances whole heart patterns leading to an accurate identification of distinct regions, mainly left (LV) and right ventricle (RV) for the purposes of this work. RESULTS: Experiments reveal that the initial location and estimated shape provided by the CNN are of great concern for the subsequent active contour stage. We assessed our method on two short data sets with Dice scores of 93% (LV-CT), 91% (LV-MRI), 0.86% (RV-CT) and 0.85% (RV-MRI). CONCLUSION: Our approach overcomes the performance of other techniques by means of a multiregion segmentation assisted by a CNN trained with a limited data set, a typical issue in medical imaging.


Assuntos
Ventrículos do Coração , Redes Neurais de Computação , Ventrículos do Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Radiografia , Tomografia Computadorizada por Raios X
2.
Eur Heart J Case Rep ; 5(4): ytab139, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34268474

RESUMO

BACKGROUND: Evaluation of acute chest pain (ACP) in the emergency department is a major health issue and differential diagnosis remains challenging for the physician, particularly in patients with atypical symptoms and inconclusive changes in electrocardiogram (ECG) or biomarkers levels. CASE SUMMARY: We present the potential value of the two-phase computed tomography angiography (TP-CTA) imaging protocol done in six different patients evaluated with ACP and underwent non-gated or gated computed tomography angiography (CTA) to exclude pulmonary embolism (PE), acute aortic syndrome (AAS), or acute coronary syndrome (ACS). All patients had new-onset chest pain and atypical clinical presentation with non-diagnostic ECG and initially negative or near-normal cardiac biomarkers. DISCUSSION: The evaluation of myocardial computed tomography perfusion (MCTP) using TP-CTA imaging protocol might open a new diagnostic approach to evaluate MCTP in patients with ACP related to PE, AAS, or ACS.

5.
Sensors (Basel) ; 20(3)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973153

RESUMO

Heart diseases are the most important causes of death in the world and over the years, thestudy of cardiac movement has been carried out mainly in two dimensions, however, it is important toconsider that the deformations due to the movement of the heart occur in a three-dimensional space.The 3D + t analysis allows to describe most of the motions of the heart, for example, the twistingmotion that takes place on every beat cycle that allows us identifying abnormalities of the heartwalls. Therefore, it is necessary to develop algorithms that help specialists understand the cardiacmovement. In this work, we developed a new approach to determine the cardiac movement inthree dimensions using a differential optical flow approach in which we use the steered Hermitetransform (SHT) which allows us to decompose cardiac volumes taking advantage of it as a model ofthe human vision system (HVS). Our proposal was tested in complete cardiac computed tomography(CT) volumes ( 3D + t), as well as its respective left ventricular segmentation. The robustness tonoise was tested with good results. The evaluation of the results was carried out through errors inforwarding reconstruction, from the volume at time t to time t + 1 using the optical flow obtained(interpolation errors). The parameters were tuned extensively. In the case of the 2D algorithm, theinterpolation errors and normalized interpolation errors are very close and below the values reportedin ground truth flows. In the case of the 3D algorithm, the results were compared with another similarmethod in 3D and the interpolation errors remained below 0.1. These results of interpolation errorsfor complete cardiac volumes and the left ventricle are shown graphically for clarity. Finally, a seriesof graphs are observed where the characteristic of contraction and dilation of the left ventricle isevident through the representation of the 3D optical flow.

6.
Arch Cardiol Mex ; 89(3): 248-253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31588134

RESUMO

Coronary artery aneurysms are described as a localized dilatation that exceeds the normal diameter by 1.5 times. This is a rare condition; its incidence varies from 0.3% up to 5.3% of all coronary angiographies. Those aneurysms that exceed 4 times the diameter of a normal artery are considered giant aneurysms, which are even more uncommon, presenting between 0.02% and 0.2% of all cases. There is controversy regarding its pathophysiology, however, up to 50% of the cases are related to atherosclerosis. They are diagnosed more frequently between the sixth and seventh decade of life. The main clinical manifestations are related to ischemic heart disease. Regarding their treatment, there is no general consensus towards its management in adult patients. The options are medical, surgical or percutaneous treatment. We report the presence of a giant aneurysm of the right coronary artery and giant ectasia of the left coronary system with active thrombosis in a man with history of an abdominal aortic aneurysm, with endovascular treatment and a non-ST segment elevation myocardial infarction with no reperfusion strategy, who required a coronary computed tomography, identifying the anatomical characteristics of this disease.


Los aneurismas de las arterias coronarias se definen como una dilatación localizada que excede el diámetro normal en 1.5 veces. Esta es una condición poco frecuente, su incidencia varía del 0.3 hasta el 5.3% de las angiografías coronarias. Los aneurismas que exceden cuatro veces el diámetro del vaso normal se consideran gigantes. Estos son aún más raros y se presentan en el 0.02 a 0.2% de todos los casos. Existe controversia en cuanto a su fisiopatología, sin embargo, hasta el 50% de los casos se relacionan con la aterosclerosis. Se diagnostican más frecuentemente entre la sexta y séptima décadas de vida. Las principales manifestaciones clínicas están relacionadas con la cardiopatía isquémica. Respecto a su tratamiento, no existe un consenso del manejo en los pacientes adultos, las opciones son: médico, quirúrgico o intervencionismo. Reportamos la presencia de un aneurisma gigante de la coronaria derecha y ectasia gigante del sistema izquierdo con trombosis activa en un hombre con antecedentes de un aneurisma en la aorta abdominal, tratado por vía endovascular, e infarto agudo al miocardio sin elevación del segmento ST no reperfundido. Requirió de estudio de angiotomografía coronaria, el cual permitió la identificación de las características anatómicas de esta enfermedad.

7.
Gac Med Mex ; 155(4): 436-444, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31486800

RESUMO

Positron-emission tomography (PET) is a medical diagnostic technique by means of which functional images are obtained by recording the spatio-temporal biodistribution of specific radiopharmaceuticals targeted at specific molecular objectives, which provides biochemical information at the molecular level. Early in the first decade of this 21st century, the Faculty of Medicine of the National Autonomous University of Mexico acquired the technology to implement this diagnostic technique in Mexico, thus becoming a pioneer in PET applications in the country and in Latin America. Almost two decades after its implementation in Mexico, PET has become an essential tool in medical clinics. This article describes the background, current state and perspectives of PET molecular imaging in Mexico, and the impact it has had on the management of patients with oncological, neurological and heart diseases.


La tomografía por emisión de positrones (PET) es una técnica de diagnóstico médico mediante la cual se obtienen imágenes funcionales a partir de registrar la biodistribución espacio-temporal de radiofármacos específicos dirigidos a blancos moleculares específicos, proveyendo información bioquímica a nivel molecular. A principios de la primera década de este siglo XXI, la Facultad de Medicina de la Universidad Nacional Autónoma de México implementó esta técnica de diagnóstico en México, convirtiéndose en pionera en aplicaciones PET en el país y Latinoamérica. Casi dos décadas después, la PET se ha convertido en una herramienta esencial en la clínica médica. En este artículo se describen los antecedentes, el estado actual, las perspectivas de la imagen molecular PET en México y el impacto que ha tenido en el manejo de pacientes con enfermedades oncológicas, neurológicas y cardiológicas.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Cardiopatias/diagnóstico por imagem , Humanos , México , Neoplasias/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem
8.
Arch. cardiol. Méx ; 89(3): 248-253, jul.-sep. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1149074

RESUMO

Resumen Los aneurismas de las arterias coronarias se definen como una dilatación localizada que excede el diámetro normal en 1.5 veces. Esta es una condición poco frecuente, su incidencia varía del 0.3 hasta el 5.3% de las angiografías coronarias. Los aneurismas que exceden cuatro veces el diámetro del vaso normal se consideran gigantes. Estos son aún más raros y se presentan en el 0.02 a 0.2% de todos los casos. Existe controversia en cuanto a su fisiopatología, sin embargo, hasta el 50% de los casos se relacionan con la aterosclerosis. Se diagnostican más frecuentemente entre la sexta y séptima décadas de vida. Las principales manifestaciones clínicas están relacionadas con la cardiopatía isquémica. Respecto a su tratamiento, no existe un consenso del manejo en los pacientes adultos, las opciones son: médico, quirúrgico o intervencionismo. Reportamos la presencia de un aneurisma gigante de la coronaria derecha y ectasia gigante del sistema izquierdo con trombosis activa en un hombre con antecedentes de un aneurisma en la aorta abdominal, tratado por vía endovascular, e infarto agudo al miocardio sin elevación del segmento ST no reperfundido. Requirió de estudio de angiotomografía coronaria, el cual permitió la identificación de las características anatómicas de esta enfermedad.


Abstract Coronary artery aneurysms are described as a localized dilatation that exceeds the normal diameter by 1.5 times. This is a rare condition; its incidence varies from 0.3% up to 5.3% of all coronary angiographies. Those aneurysms that exceed 4 times the diameter of a normal artery are considered giant aneurysms, which are even more uncommon, presenting between 0.02% and 0.2% of all cases. There is controversy regarding its pathophysiology, however, up to 50% of the cases are related to atherosclerosis. They are diagnosed more frequently between the sixth and seventh decade of life. The main clinical manifestations are related to ischemic heart disease. Regarding their treatment, there is no general consensus towards its management in adult patients. The options are medical, surgical or percutaneous treatment. We report the presence of a giant aneurysm of the right coronary artery and giant ectasia of the left coronary system with active thrombosis in a man with history of an abdominal aortic aneurysm, with endovascular treatment and a non-ST segment elevation myocardial infarction with no reperfusion strategy, who required a coronary computed tomography, identifying the anatomical characteristics of this disease.


Assuntos
Humanos , Masculino , Idoso , Trombose/diagnóstico por imagem , Aneurisma Coronário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Aneurisma da Aorta Abdominal/terapia , Dilatação Patológica/diagnóstico por imagem , Infarto do Miocárdio sem Supradesnível do Segmento ST/fisiopatologia
9.
Gac. méd. Méx ; 155(4): 436-444, jul.-ago. 2019. tab, graf
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1286530

RESUMO

Resumen La tomografía por emisión de positrones (PET) es una técnica de diagnóstico médico mediante la cual se obtienen imágenes funcionales a partir de registrar la biodistribución espacio-temporal de radiofármacos específicos dirigidos a blancos moleculares específicos, proveyendo información bioquímica a nivel molecular. A principios de la primera década de este siglo XXI, la Facultad de Medicina de la Universidad Nacional Autónoma de México implementó esta técnica de diagnóstico en México, convirtiéndose en pionera en aplicaciones PET en el país y Latinoamérica. Casi dos décadas después, la PET se ha convertido en una herramienta esencial en la clínica médica. En este artículo se describen los antecedentes, el estado actual, las perspectivas de la imagen molecular PET en México y el impacto que ha tenido en el manejo de pacientes con enfermedades oncológicas, neurológicas y cardiológicas.


Abstract Positron-emission tomography (PET) is a medical diagnostic technique by means of which functional images are obtained by recording the spatio-temporal biodistribution of specific radiopharmaceuticals targeted at specific molecular objectives, which provides biochemical information at the molecular level. Early in the first decade of this 21st century, the Faculty of Medicine of the National Autonomous University of Mexico acquired the technology to implement this diagnostic technique in Mexico, thus becoming a pioneer in PET applications in the country and in Latin America. Almost two decades after its implementation in Mexico, PET has become an essential tool in medical clinics. This article describes the background, current state and perspectives of PET molecular imaging in Mexico, and the impact it has had on the management of patients with oncological, neurological and heart diseases.


Assuntos
Humanos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Cardiopatias/diagnóstico por imagem , México , Neoplasias/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem
10.
Arch Cardiol Mex ; 89(3): 227-232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31967588

RESUMO

Coronary artery aneurysms are described as a localized dilatation that exceeds the normal diameter by 1.5 times. This is a rare condition; its incidence varies from 0.3% up to 5.3% of all coronary angiographies. Those aneurysms that exceed 4 times the diameter of a normal artery are considered giant aneurysms, which are even more uncommon, presenting between 0.02% and 0.2% of all cases. There is controversy regarding its pathophysiology, however, up to 50% of the cases are related to atherosclerosis. They are diagnosed more frequently between the sixth and seventh decade of life. The main clinical manifestations are related to ischemic heart disease. Regarding their treatment, there is no general consensus toward its management in adult patients. The options are medical, surgical, or percutaneous treatment. We report the presence of a giant aneurysm of the right coronary artery and giant ectasia of the left coronary system with active thrombosis in a man with a history of an abdominal aortic aneurysm, with endovascular treatment and a non-ST segment elevation myocardial infarction with no reperfusion strategy, who required a coronary computed tomography, identifying the anatomical characteristics of this disease.


Los aneurismas de las arterias coronarias se definen como una dilatación localizada que excede el diámetro normal en 1.5 veces. Esta es una condición poco frecuente, su incidencia varía del 0.3 hasta el 5.3% de las angiografías coronarias. Los aneurismas que exceden cuatro veces el diámetro del vaso normal se consideran gigantes. Estos son aún más raros y se presentan en el 0.02 a 0.2% de todos los casos. Existe controversia en cuanto a su fisiopatología, sin embargo, hasta el 50% de los casos se relacionan con la aterosclerosis. Se diagnostican más frecuentemente entre la sexta y séptima décadas de vida. Las principales manifestaciones clínicas están relacionadas con la cardiopatía isquémica. Respecto a su tratamiento, no existe un consenso del manejo en los pacientes adultos, las opciones son: médico, quirúrgico o intervencionismo. Reportamos la presencia de un aneurisma gigante de la coronaria derecha y ectasia gigante del sistema izquierdo con trombosis activa en un hombre con antecedentes de un aneurisma en la aorta abdominal, tratado por vía endovascular, e infarto agudo al miocardio sin elevación del segmento ST no reperfundido. Requirió de estudio de angiotomografía coronaria, el cual permitió la identificación de las características anatómicas de esta enfermedad.


Assuntos
Aneurisma Coronário/diagnóstico por imagem , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Aneurisma da Aorta Abdominal/terapia , Dilatação Patológica/diagnóstico por imagem , Humanos , Masculino , Infarto do Miocárdio sem Supradesnível do Segmento ST/fisiopatologia
11.
Comput Biol Med ; 87: 236-249, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28618336

RESUMO

In recent years, computed tomography (CT) has become a standard technique in cardiac imaging because it provides detailed information that may facilitate the diagnosis of the conditions that interfere with correct heart function. However, CT-based cardiac diagnosis requires manual segmentation of heart cavities, which is a difficult and time-consuming task. Thus, in this paper, we propose a novel technique to segment endocardium and epicardium boundaries based on a 2D approach. The proposal computes relevant information of the left ventricle and its adjacent structures using the Hermite transform. The novelty of the work is that the information is combined with active shape models and level sets to improve the segmentation. Our database consists of mid-third slices selected from 28 volumes manually segmented by expert physicians. The segmentation is assessed using Dice coefficient and Hausdorff distance. In addition, we introduce a novel metric called Ray Feature error to evaluate our method. The results show that the proposal accurately discriminates cardiac tissue. Thus, it may be a useful tool for supporting heart disease diagnosis and tailoring treatments.


Assuntos
Ventrículos do Coração/patologia , Humanos , Modelos Biológicos , Tomografia Computadorizada por Raios X/métodos
12.
Comput Math Methods Med ; 2017: 3087407, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28348637

RESUMO

Cardiac resynchronization therapy (CRT) improves functional classification among patients with left ventricle malfunction and ventricular electric conduction disorders. However, a high percentage of subjects under CRT (20%-30%) do not show any improvement. Nonetheless the presence of mechanical contraction dyssynchrony in ventricles has been proposed as an indicator of CRT response. This work proposes an automated classification model of severity in ventricular contraction dyssynchrony. The model includes clinical data such as left ventricular ejection fraction (LVEF), QRS and P-R intervals, and the 3 most significant factors extracted from the factor analysis of dynamic structures applied to a set of equilibrium radionuclide angiography images representing the mechanical behavior of cardiac contraction. A control group of 33 normal volunteers (28 ± 5 years, LVEF of 59.7% ± 5.8%) and a HF group of 42 subjects (53.12 ± 15.05 years, LVEF < 35%) were studied. The proposed classifiers had hit rates of 90%, 50%, and 80% to distinguish between absent, mild, and moderate-severe interventricular dyssynchrony, respectively. For intraventricular dyssynchrony, hit rates of 100%, 50%, and 90% were observed distinguishing between absent, mild, and moderate-severe, respectively. These results seem promising in using this automated method for clinical follow-up of patients undergoing CRT.


Assuntos
Insuficiência Cardíaca/diagnóstico por imagem , Coração/diagnóstico por imagem , Informática Médica/métodos , Processamento de Sinais Assistido por Computador , Adulto , Algoritmos , Angiografia , Arritmias Cardíacas/fisiopatologia , Calibragem , Terapia de Ressincronização Cardíaca/métodos , Processamento Eletrônico de Dados , Feminino , Voluntários Saudáveis , Coração/fisiopatologia , Sistema de Condução Cardíaco , Insuficiência Cardíaca/terapia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Contração Miocárdica , Reprodutibilidade dos Testes , Resultado do Tratamento , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda
13.
Arch. cardiol. Méx ; 83(3): 176-182, jul.-sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-703013

RESUMO

Objective: Cardiopulmonary exercise testing is a tool that helps clinicians to establish diagnosis and calculate risk stratification in adults. However, the utility of this test among children with congenital heart disease has not been fully explored. The goal of this study was to describe reference values for cardiopulmonary performance of healthy children. Methods: This study included 103 apparently healthy children (aged from 4 to 18 years; 61 boys), who underwent cardiopulmonary test using a treadmill protocol. All tests took place at 2240m above sea level (Mexico City). Results: Exercise time was 11 ± 4 min. There were no complications. Peak oxygen uptake correlated closely with height in both genders (girls r = 0.84; boys r = 0.84, p < 0.001). A multivariable linear regression model showed that body surface area, exercise time, gender and heart rate reserve were significant predictors of peak oxygen uptake (R² =0.815, p<0.001). Peak oxygen uptake was strongly associated with age even among children younger than thirteen years (r = 0.74, p <0.001). Conclusion: This study provides physiological values for the major cardiopulmonary variables obtained from exercise testing using a treadmill among healthy children. Cardiopulmonary exercise test can be safely and effectively performed in young children even as young as 4 years old. Variables including age, gender and height are strongly associated with exercise time, peak heart rate and peak oxygen uptake. Regression equations for predicting peak heart rate and peak oxygen uptake are presented as reference values that allow researchers to compare children with heart disease versus those who are healthy.


Objetivo: La prueba de esfuerzo cardiopulmonar es una herramienta que ayuda a los médicos a establecer el diagnóstico y estratificar el riesgo en adultos. Sin embargo, su utilidad en los niños no se ha explorado a fondo. El objetivo fue describir los valores de esta prueba en niños sanos en altitud moderadamente alta. Métodos: Se realizaron pruebas de esfuerzo cardiopulmonar a 103 niños sanos (4 a 18 años, 61 varones) mediante tapiz rodante y a 2240m sobre el nivel del mar (Ciudad de México). Resultados: El tiempo de ejercicio fue de 11 ± 4 min, sin complicaciones. El consumo de oxígeno pico se correlacionó estrechamente con la talla en ambos géneros (niñas r = 0.84; niños r = 0.84, p < 0.001). El modelo multivariado que incluyó superficie corporal, tiempo de ejercicio, género y la frecuencia cardíaca de reserva fue un fuerte predictor del consumo de oxígeno pico (R²=0.815, p<0.001). Conclusión: Las pruebas de esfuerzo cardiopulmonar mediante tapiz rodante se pueden realizar con seguridad y eficacia en niños, incluso de 4 años de edad. Variables como la edad, el género y la talla están fuertemente asociados con el tiempo de ejercicio, la frecuencia cardiaca máxima y el de oxígeno pico. Las ecuaciones de regresión obtenidas para calcular la frecuencia cardíaca máxima y el consumo de oxígeno pico pueden ayudar, tanto a clínicos como a investigadores, a comparar el comportamiento de niños con cardiopatías frente a los que no las tienen.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Altitude , Teste de Esforço , Valores de Referência
14.
Arch Cardiol Mex ; 83(3): 176-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23856318

RESUMO

OBJECTIVE: Cardiopulmonary exercise testing is a tool that helps clinicians to establish diagnosis and calculate risk stratification in adults. However, the utility of this test among children with congenital heart disease has not been fully explored. The goal of this study was to describe reference values for cardiopulmonary performance of healthy children. METHODS: This study included 103 apparently healthy children (aged from 4 to 18 years; 61 boys), who underwent cardiopulmonary test using a treadmill protocol. All tests took place at 2240m above sea level (Mexico City). RESULTS: Exercise time was 11±4min. There were no complications. Peak oxygen uptake correlated closely with height in both genders (girls r=0.84; boys r=0.84, p<0.001). A multivariable linear regression model showed that body surface area, exercise time, gender and heart rate reserve were significant predictors of peak oxygen uptake (R(2)=0.815, p<0.001). Peak oxygen uptake was strongly associated with age even among children younger than thirteen years (r=0.74, p<0.001). CONCLUSION: This study provides physiological values for the major cardiopulmonary variables obtained from exercise testing using a treadmill among healthy children. Cardiopulmonary exercise test can be safely and effectively performed in young children even as young as 4 years old. Variables including age, gender and height are strongly associated with exercise time, peak heart rate and peak oxygen uptake. Regression equations for predicting peak heart rate and peak oxygen uptake are presented as reference values that allow researchers to compare children with heart disease versus those who are healthy.


Assuntos
Altitude , Teste de Esforço , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Valores de Referência
15.
Comput Math Methods Med ; 2013: 617604, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23634177

RESUMO

Radionuclide-based imaging is an alternative to evaluate ventricular function and synchrony and may be used as a tool for the identification of patients that could benefit from cardiac resynchronization therapy (CRT). In a previous work, we used Factor Analysis of Dynamic Structures (FADS) to analyze the contribution and spatial distribution of the 3 most significant factors (3-MSF) present in a dynamic series of equilibrium radionuclide angiography images. In this work, a probability density function model of the 3-MSF extracted from FADS for a control group is presented; also an index, based on the likelihood between the control group's contraction model and a sample of normal subjects is proposed. This normality index was compared with those computed for two cardiopathic populations, satisfying the clinical criteria to be considered as candidates for a CRT. The proposed normality index provides a measure, consistent with the phase analysis currently used in clinical environment, sensitive enough to show contraction differences between normal and abnormal groups, which suggests that it can be related to the degree of severity in the ventricular contraction dyssynchrony, and therefore shows promise as a follow-up procedure for patients under CRT.


Assuntos
Função Ventricular/fisiologia , Algoritmos , Terapia de Ressincronização Cardíaca , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/terapia , Biologia Computacional , Análise Fatorial , Análise de Fourier , Imagem do Acúmulo Cardíaco de Comporta/estatística & dados numéricos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Modelos Estatísticos , Contração Miocárdica/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia
16.
Gac Med Mex ; 148(1): 6-13, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-22367303

RESUMO

UNLABELLED: Single photon emission computed tomography (SPECT) myocardial perfusion imaging is widely used for diagnosing coronary artery disease (CAD). However, SPECT costs, imaging time, and radiation exposure, limit SPECT indications. OBJECTIVE: Determine whether a stress-only SPECT imaging would be enough to obtain a diagnosis of CAD improving nuclear laboratory efficiency. METHODS: 122 patients with unknown CAD were evaluated with stress-only SPECT imaging. In order to evaluate diagnostic accuracy and the prognostic value of the stress-only protocol, patients with abnormal SPECT underwent invasive angiography and patients with normal SPECT were followed-up during 3 years. RESULTS: Diagnosis time, SPECT cost, and radiopharmaceutical dosage were significantly lower as compared with the conventional SPECT imaging protocol (30, 40 and 55%, respectively). Diagnostic accuracy and cardiac prognosis information were comparable to those obtained with the conventional imaging protocol (positive predictive value for CAD of 85% and negative predictive value for cardiac events of 97%). CONCLUSIONS: In patients with intermediate risk for CAD, stress-only SPECT imaging will significantly improve nuclear laboratory efficiency, and with similar accuracy than that the one obtained with the conventional protocol.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/economia , Tomografia Computadorizada de Emissão de Fóton Único/economia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Arch Cardiol Mex ; 81(2): 75-81, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21775239

RESUMO

INTRODUCTION: Significant Coronary Artery Disease (CAD>50%) it can easily detected with Multislice Computed Tomography (MSCT), nevertheless if MSCT may replace Invasive Coronary Angiography (ICA) in the preoperative assessment of the patient undergoing to non-coronary cardiac surgery is not well defined. The objective of this study was to know if the MSCT can replace ICA in the preoperative valuation of patients who go to cardiac surgery METHOD: 64 consecutive patients in Class I recommendation of American College of Cardiology / American Heart Association (ACC/AHA) guidelines for preoperative ICA were evaluated. Patients with angina, contrast medium allergy, serum creatinine up to 2.0 mg/dL, previous coronary cardiac surgery or coronary angioplasty and supraventricular arrhythmias were excluded. Both, Coronary artery calcium (CAC) and coronary angiography were evaluated. RESULTS: The prevalence of significant (>50%) CAD was 12.5%. The Sensitivity of MSCT to detect significant CAD was 87.5%, its Specificity of 92.8%, Predictive Negative Value was 98.1% and Area Under the Curve (ROC analysis) = 0.90. Anyone with Rheumatic Valvular Disease had significant CAD or CAC>400 UA (RR = 0.80, IC95% 0.69-0.94). Degenerative Aortic Valve Stenosis had a major probability of significant CAD (RR of 9.0; IC 95% 1.64-49.80). Logistic Regression Analysis showed than CAC>400 UA (Coef ß 0,351, t = 4.402 p = 0.000) and male gender (Coef ß 0,179, t = 2.445, p = 0.017), were the best predicting variables of CAD. This study shows different populations in patients undergoing to non-coronary cardiac surgery. CONCLUSIONS: Gender, CAC> 400 UA and type of cardiac disease previously surgery may be useful for triage to MSCT or ICA in the preoperative assessment. This study shows that ICA may be necessarily indicated in some patients in assessment of non-coronary cardiac surgery but not absolutely indicated in all patients that Guidelines of ACC/AHA have recommended.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Cuidados Pré-Operatórios , Angiografia Coronária/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
18.
Arch. cardiol. Méx ; 81(2): 75-81, abr.-jun. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-632024

RESUMO

Introducción: En la actualidad la enfermedad coronaria obstructiva (obstrucción mayor de 50%) puede ser fácilmente evaluada por medio de la tomografía coronaria multicorte. Sin embargo, aún no se define si ésta puede reemplazar a la angiografía coronaria invasiva, en pacientes que van a cirugía cardiaca no coronaria. Objetivo: Conocer si la tomografía coronaria multicorte puede sustituir a la angiografía coronaria invasiva en la detección de enfermedad coronaria en pacientes que van a ser operados de cirugía cardiaca no coronaria; comparando entre si la sensibilidad y especificidad de ambos métodos en la detección de enfermedad coronaria. Método: Se incluyeron consecutivamente 64 pacientes con edades de 55.17 ± 12.73 años, en Clase I de las guías del Colegio Americano de Cardiología/Asociación Americana de Corazón para realizar angiografía coronaria en el preoperatorio de cirugía cardiaca no coronaria. Se excluyeron enfermos con angina de pecho, alergia al medio de contraste, creatinina sérica por arriba de 2.0 mg/dL, que tuvieran previamente cirugía cardiaca o angioplastia coronaria y arritmias supra-ventriculares. Se analizó la anatomía coronaria y se cuantificó la cantidad de calcio coronario. Resultados: La prevalencia de obstrucción coronaria mayor de 50% fue 12.5%. La tomografía coronaria multicorte mostró sensibilidad de 87.5%, especificidad de 92.8%, valor predictivo negativo de 98.1% y área bajo la curva de 0.90, para predecir obstrucción coronaria. Ningún paciente con valvulopatía reumática tuvo obstrucción coronaria mayor de 50% o score de calcio > 400 U A (RR = 0.80, IC 95% 0.69-0.94). La estenosis valvular aórtica degenerativa tuvo mayor probabilidad de obstrucción coronaria mayor de 50% (RR = 9.0: IC 95% 1.64-49.8). Con análisis multivariado usando regresión logística, el score de calcio mayor de 400 UA (Coef ß 0.342, t = 4.297, p = 0.000) y sexo masculino (Coef ß 0.174, t = 2.214, p = 0.031), fueron las variables predictoras de más peso. Este estudio muestra poblaciones diferentes en el grupo de pacientes que van a cirugía cardiaca no coronaria. Conclusiones: El género masculino, el calcio coronario mayor de 400 UA y el tipo de enfermedad cardiaca previa a la cirugía cardiaca no coronaria pueden ser variables útiles para realizar la selección de pacientes que pueden evaluarse con tomografía coronaria multicorte o con angiografía coronaria invasiva. La angiografía coronaria invasiva puede indicarse necesariamente en algunos pacientes que van a cirugía cardiaca no coronaria, pero no es absolutamente necesaria en todos los enfermos como hasta hoy se recomienda en las guías del Colegio Americano de Cardiología y la Asociación Americana de Corazón.


Introduction: Significant Coronary Artery Disease (CAD>50%) it can easily detected with Multislice Computed Tomography (MSCT), nevertheless if MSCT may replace Invasive Coronary Angiography (ICA) in the preoperative assessment of the patient undergoing to non-coronary cardiac surgery is not well defined. The objective of this study was to know if the MSCT can replace ICA in the preoperative valuation of patients who go to cardiac surgery Method: 64 consecutive patients in Class I recommendation of American College of Cardiology / American Heart Association (ACC/AHA) guidelines for preoperative ICA were evaluated. Patients with angina, contrast medium allergy, serum creatinine up to 2.0 mg/dL, previous coronary cardiac surgery or coronary angioplasty and supraventricular arrhythmias were excluded. Both, Coronary artery calcium (CAC) and coronary angiography were evaluated. Results: The prevalence of significant (>50%) CAD was 12.5%. The Sensitivity of MSCT to detect significant CAD was 87.5%, its Specificity of 92.8%, Predictive Negative Value was 98.1% and Area Under the Curve (ROC analysis) = 0.90. Anyone with Rheumatic Valvular Disease had significant CAD or CAC>400 UA (RR = 0.80, IC95% 0.69-0.94). Degenerative Aortic Valve Stenosis had a major probability of significant CAD (RR of 9.0; IC 95% 1.64-49.80). Logistic Regression Analysis showed than CAC>400 UA (Coef ß 0,351, t = 4.402 p = 0.000) and male gender (Coef ß 0,179, t = 2.445, p = 0.017), were the best predicting variables of CAD. This study shows different populations in patients undergoing to non-coronary cardiac surgery. Conclusions: Gender, CAC> 400 UA and type of cardiac disease previously surgery may be useful for triage to MSCT or ICA in the preoperative assessment. This study shows that ICA may be necessarily indicated in some patients in assessment of non-coronary cardiac surgery but not absolutely indicated in all patients that Guidelines of ACC/AHA have recommended.


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Cardíacos , Doença da Artéria Coronariana , Tomografia Computadorizada Multidetectores , Cuidados Pré-Operatórios , Angiografia Coronária/métodos , Valor Preditivo dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA