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1.
J Clin Ultrasound ; 49(4): 423-427, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33037630

RESUMEN

We report the case of a fetus presenting aortic arch anomalies associated with a ventricular septal defect (VSD). This fetus, which was referred at 25 weeks of gestation, was suspected to have coarctation of aorta (CoA) evidenced by enlarged right chambers at the four-chamber view during a routine obstetric ultrasonographic scan. The prenatal diagnosis of CoA remains a challenge. Here, we review the ultrasonographic findings that could contribute to this diagnosis.


Asunto(s)
Aorta Torácica/anomalías , Aorta Torácica/diagnóstico por imagen , Defectos del Tabique Interventricular/diagnóstico por imagen , Aorta Torácica/embriología , Coartación Aórtica/diagnóstico por imagen , Coartación Aórtica/embriología , Angiografía por Tomografía Computarizada/métodos , Ecocardiografía Tridimensional/métodos , Femenino , Feto/diagnóstico por imagen , Humanos , Masculino , Embarazo , Diagnóstico Prenatal/métodos , Ultrasonografía Prenatal/métodos
2.
Radiology ; 265(3): 724-32, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23091172

RESUMEN

PURPOSE: To determine the utility of cardiac magnetic resonance (MR) T1 mapping for quantification of diffuse myocardial fibrosis compared with the standard of endomyocardial biopsy. MATERIALS AND METHODS: This HIPAA-compliant study was approved by the institutional review board. Cardiomyopathy patients were retrospectively identified who had undergone endomyocardial biopsy and cardiac MR at one institution during a 5-year period. Forty-seven patients (53% male; mean age, 46.8 years) had undergone diagnostic cardiac MR and endomyocardial biopsy. Thirteen healthy volunteers (54% male; mean age, 38.1 years) underwent cardiac MR as a reference. Myocardial T1 mapping was performed 10.7 minutes ± 2.7 (standard deviation) after bolus injection of 0.2 mmol/kg gadolinium chelate by using an inversion-recovery Look-Locker sequence on a 1.5-T MR imager. Late gadolinium enhancement was assessed by using gradient-echo inversion-recovery sequences. Cardiac MR results were the consensus of two radiologists who were blinded to histopathologic findings. Endomyocardial biopsy fibrosis was quantitatively measured by using automated image analysis software with digital images of specimens stained with Masson trichrome. Histopathologic findings were reported by two pathologists blinded to cardiac MR findings. Statistical analyses included Mann-Whitney U test, analysis of variance, and linear regression. RESULTS: Median myocardial fibrosis was 8.5% (interquartile range, 5.7-14.4). T1 times were greater in control subjects than in patients without and in patients with evident late gadolinium enhancement (466 msec ± 14, 406 msec ± 59, and 303 msec ± 53, respectively; P < .001). T1 time and histologic fibrosis were inversely correlated (r = -0.57; 95% confidence interval: -0.74, -0.34; P < .0001). The area under the curve for myocardial T1 time to detect fibrosis of greater than 5% was 0.84 at a cutoff of 383 msec. CONCLUSION: Cardiac MR with T1 mapping can provide noninvasive evidence of diffuse myocardial fibrosis in patients referred for evaluation of cardiomyopathy.


Asunto(s)
Biopsia/métodos , Cardiomiopatías/patología , Fibrosis Endomiocárdica/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Distribución de Chi-Cuadrado , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Coloración y Etiquetado , Estadísticas no Paramétricas
3.
Radiology ; 264(3): 876-83, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22771879

RESUMEN

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.


Asunto(s)
Fibrosis Endomiocárdica/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Imagen Sincronizada Cardíacas , Medios de Contraste , Femenino , Fibrosis , Humanos , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dosis de Radiación
4.
Radiol Bras ; 55(3): 156-160, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35795603

RESUMEN

Objective: To compare the degree of coronary stenosis (≥ 50% luminal narrowing) determined by coronary computed tomography angiography (CCTA) with that determined by invasive coronary angiography (ICA), using segment-by-segment analysis. Materials and Methods: This was a retrospective study of the records of patients who underwent CCTA and ICA between January 2014 and June 2018 at a general hospital in Brazil. Receiver operating characteristic curve analysis was applied, and the areas under the curve were used in order to assess the overall accuracy of the methods. Results: The degree of coronary stenosis was evaluated in a total of 844 arterial segments. The diagnostic performance of CCTA was good, with a sensitivity of 82.3%, a specificity of 96.4%, and a negative predictive value of 97.7% (95% CI: 96.5-98.5). In the segment-by-segment analysis, CCTA had excellent accuracy for the left main coronary artery and for other segments. Conclusion: In clinical practice at general hospitals, CCTA appears to have diagnostic performance comparable to that of ICA.


Objetivo: O objetivo do estudo é comparar os graus de estenose coronariana (≥ 50% de redução luminal) determinados pela tomografia computadorizada e pelo cateterismo, utilizando uma análise segmento a segmento. Materiais e Métodos: Estudo retrospectivo conduzido em pacientes que foram submetidos a tomografia computadorizada e a cateterismo, de janeiro de 2014 a junho de 2018, em um hospital geral. A análise da curva característica de operação do receptor foi utilizada para a análise da acurácia. Resultados: Na avaliação dos vasos, em um total de 844 segmentos, o desempenho da tomografia computadorizada foi bom, com sensibilidade de 82,3%, especificidade de 96,4% e valor preditivo negativo de 97,7% (IC 95%: 96,5-98,5). Na análise segmento a segmento, o tronco da coronária esquerda, assim como outros segmentos, apresentaram excelente acurácia. Conclusão: A tomografia computadorizada mostrou bom desempenho diagnóstico quando comparada com o cateterismo na prática diária de um hospital geral.

5.
J Magn Reson Imaging ; 34(6): 1367-73, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21954119

RESUMEN

PURPOSE: To evaluate the relationship between "Look-Locker" (LL) and modified Look-Locker Inversion recovery (MOLLI) approaches for T1 mapping of the myocardium. MATERIALS AND METHODS: A total of 168 myocardial T1 maps using MOLLI and 165 maps using LL were obtained in human subjects at 1.5 Tesla. The T1 values of the myocardium were calculated before and at five time points after gadolinium administration. All time and heart rate normalizations were done. The T1 values obtained were compared to determine the absolute and bias agreement. RESULTS: The precontrast global T1 values were similar when measured by the LL and by MOLLI technique (mean, 1004.9 ms ± 120.3 versus 1034.1 ms ± 53.1, respectively, P = 0.26). Postcontrast myocardial T1 time from LL was significantly longer than MOLLI from 5 to 25 min (mean difference, LL - MOLLI was +61.8 ± 46.4 ms, P < 0.001). No significant differences in T1 values were noted between long and short axis measurements for either MOLLI or LL. CONCLUSION: Postcontrast LL and MOLLI showed very good agreement, although LL values are higher than MOLLI. Precontrast T1 values showed good agreement, however LL has greater limits of agreement. Short and long axis planes can reliably assess T1 values.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Miocardio/patología , Adolescente , Adulto , Medios de Contraste , Femenino , Gadolinio , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
6.
Radiol Bras ; 54(4): 261-264, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34393294

RESUMEN

Almost two decades ago, it became possible to use coronary computed tomography for the noninvasive assessment of the coronary arteries. That is an extremely accurate method for detecting or excluding coronary artery disease, even the subclinical forms. This pictorial essay aims to show the main imaging findings in 47 coronary computed tomography scans acquired at a general hospital between January 2014 and June 2018. The most common findings were atheromatous plaques (in 87%) and stents (in 34%). There were also incidental findings, not directly related to coronary artery disease, such as pulmonary nodules and aortic stenosis.


Há quase duas décadas, tornou-se possível a avaliação não invasiva das coronárias por meio da angiotomografia. Esta é bastante importante para excluir ou detectar doença arterial coronariana, mesmo que subclínica. Este ensaio tem o objetivo de mostrar os principais achados de imagem em 47 angiotomografias realizadas de janeiro de 2014 a junho de 2018 em um hospital geral. Os achados mais frequentes foram a presença de placas ateromatosas (87%) e stents (34%). Além desses, houve também achados incidentais não relacionados diretamente com doença arterial coronariana, como nódulos pulmonares e estenose aórtica.

7.
Arq Bras Cardiol ; 115(3): 493-500, 2020 09.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-33027372

RESUMEN

BACKGROUND: Cardiovascular disease is the leading cause of mortality in the world. Parietal calcifications of the arteries may be visualized and quantified at initial and subclinical states by computed tomography (CT), and expressed as calcium score (CS). It is possible to estimate the prognosis of future cardiovascular events using this score. OBJECTIVES: To correlate the detection and quantification of the CS obtained by chest CT with that obtained by electrocardiography (ECG)-synchronized cardiac computed tomography (the gold-standard). METHOD: Cross-sectional, descriptive study of 73 consecutive patients in investigation for coronary artery disease who underwent cardiac CT between June 2013 and October 2014. Chest computed tomography and CS protocols were performed in a 64-channel TC scanner. P-values <0.05 were considered statistically significant. RESULTS: In the per-patient analysis, after logarithmic transformation, mean CS was 8.7 and 9.4 by the ECG-synchronized method and chest CT, respectively. The prevalence of disease was 49.3% (n=36), with a sensitivity of 97.2% and specificity of 100.0%. There was an excellent correlation between the methods (r= 0.993, p<0.001). In the per-segment analysis, after logarithmic transformation, mean CS was 3.0 and 3.2 by the ECG-synchronized method and chest CT, respectively. The prevalence of disease was 29.5% (n=86), with a sensitivity of 95.3% and specificity of 97.5%. There was an excellent correlation between the methods (r= 0.985, p<0.001). CONCLUSION: ECG-synchronized CT is well correlated with the non-ECG-synchronized CT for CS determination, without statistical difference between the methods. (Arq Bras Cardiol. 2020; 115(3):493-500).


FUNDAMENTO: A doença cardiovascular representa a principal causa de mortalidade no mundo. Calcificações parietais nas artérias podem ser visualizadas e quantificadas por tomografia computadorizada (TC) em estágios iniciais e subclínicos, sendo expressa em escore de cálcio (EC). Com esse número, é possível estimar o prognóstico de eventos cardiovasculares futuros. OBJETIVOS: Correlacionar a detecção e quantificação do EC pela TC do tórax utilizando como padrão-ouro a TC cardíaca sincronizada ao eletrocardiograma. MÉTODOS: Estudo transversal e descritivo que selecionou pacientes (n=73) consecutivos para investigação de doença arterial coronariana estável e que realizaram TC cardíaca no período de junho de 2013 a outubro de 2014. Realizado protocolo com TC do tórax e EC, em aparelho de 64 canais. Os valores de p<0,05 foram considerados estatisticamente significativos. RESULTADOS: Na avaliação por paciente, após a transformação logarítmica a média do EC sincronizado foi de 8,7 e na TC de tórax foi de 9,4. Prevalência de doença de 49,3% (n= 36). A sensibilidade foi de 97,2% e a especificidade de 100,0%. Observou-se excelente correlação entre os métodos (r= 0,993 com p<0,001). Na avaliação por segmento, a média do EC sincronizado foi de 3,0. Já a média do EC na TC de tórax foi de 3,2. Prevalência de doença de 29,5% (n= 86), com sensibilidade de 95,3% e especificidade de 97,5%. Observou-se também excelente correlação entre os métodos (r= 0,985 com p<0,001). CONCLUSÃO: O EC sincronizado e não sincronizado têm boa correlação entre si e não mostram resultados estatisticamente diferentes. (Arq Bras Cardiol. 2020; 115(3):493-500).


Asunto(s)
Calcio , Enfermedad de la Arteria Coronaria , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estudios Transversales , Humanos , Tórax , Tomografía Computarizada por Rayos X
8.
Magn Reson Imaging Clin N Am ; 27(3): 563-574, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31279457

RESUMEN

Cardiac fibrosis, characterized by net accumulation of extracellular matrix in the myocardium, is a common final pathway of heart failure. This myocardial fibrosis (MF) is not necessarily the primary cause of dysfunction; it often results from a reparative process activated in response to cardiomyocyte injury. In light of currently available treatments, late-identified MF could be definitive or irreversible, associated with worsening ventricular systolic function, abnormal cardiac remodeling, and increased ventricular stiffness and arrhythmia. T1 mapping should be used to detect incipient changes leading to myocardial damage in several clinical conditions and also in subclinical disease. This article reviews available techniques for MF detection, focusing on noninvasive quantification of diffuse fibrosis and clinical applications.


Asunto(s)
Cardiopatías/diagnóstico por imagen , Cardiopatías/patología , Imagen por Resonancia Magnética/métodos , Fibrosis , Corazón/diagnóstico por imagen , Humanos , Miocardio/patología
9.
Arq Bras Cardiol ; 113(4): 758-767, 2019.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-31691758

RESUMEN

Coronary computed tomography angiography (CCTA) has gained a prominent role in the evaluation of coronary artery disease. However, its anatomical nature does not allow the evaluation of the functional repercussion of coronary obstructions. It has been made possible to evaluate Myocardial computed tomography perfusion (Myocardial CTP) recently, based on myocardial contrast changes related to coronary stenoses. Several studies have validated this technique against the anatomical reference method (cardiac catheterization) and other functional methods, including myocardial perfusion scintigraphy and fractional flow reserve. The Myocardial CTP is performed in conjunction with the CCTA, a combined analysis of anatomy and function. The stress phase (with assessment of myocardial perfusion) can be performed before or after the resting phase (assessment of resting perfusion and coronary arteries), and different acquisition parameters are proposed according to the protocol and type of equipment used. Stressors used are based on coronary vasodilation (e.g. dipyridamole, adenosine). Image interpretation, similar to other perfusion assessment methods, is based on the identification and quantification of myocardial perfusion defects. The integration of both perfusion and anatomical findings is fundamental for the examination interpretation algorithm, allowing to define if the stenoses identified are hemodynamically significant and may be related to myocardial ischemia.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Imagen de Perfusión Miocárdica/métodos , Angiografía por Tomografía Computarizada/normas , Medios de Contraste , Angiografía Coronaria/normas , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Humanos , Isquemia Miocárdica/diagnóstico por imagen , Imagen de Perfusión Miocárdica/normas
10.
Arq Bras Cardiol ; 113(6): 1092-1101, 2019 12.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-31596324

RESUMEN

BACKGROUND: Functional assessment to rule out myocardial ischemia using coronary computed tomography angiography (CCTA) is extremely important and data on the Brazilian population are still limited. OBJECTIVE: To assess the diagnostic performance of myocardial perfusion by CCTA in the detection of severe obstructive coronary artery disease (CAD) compared with single-photon emission computerized tomography (SPECT). To analyze the importance of anatomical knowledge to understand the presence of myocardial perfusion defects on SPECT imaging that is not identified on computed tomography (CT) scan. METHOD: A total of 35 patients were evaluated by a simultaneous pharmacologic stress protocol. Fisher's exact test was used to compare proportions. The patients were grouped according to the presence or absence of significant CAD. The area under the ROC curve was used to identify the diagnostic performance of CCTA and SPECT in perfusion assessment. P < 0.05 values were considered statistically significant. RESULTS: For detection of obstructive CAD, CT myocardial perfusion analysis yielded an area under the ROC curve of 0.84 [a 95% confidence interval (CI95%): 0.67-0.94, p < 0.001]. SPECT myocardial perfusion imaging, on the other hand, showed an AUC of 0.58 (95% CI 0.40 - 0.74, p < 0.001). In this study, false-positive results with SPECT are described. CONCLUSION: Myocardial perfusion analysis by CTA displays satisfactory results compared to SPECT in the detection of obstructive CAD. CCTA can rule out false-positive results of SPECT.


Asunto(s)
Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Cineangiografía/métodos , Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Daño por Reperfusión Miocárdica/diagnóstico por imagen , Daño por Reperfusión Miocárdica/fisiopatología , Curva ROC , Sensibilidad y Especificidad
11.
Radiol Bras ; 51(1): 8-12, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29540942

RESUMEN

OBJECTIVE: To evaluate the accuracy of visual analysis and of the coronary artery calcium (CAC) score in nontriggered computed tomography (CT), in comparison with that of the CAC score in electrocardiogram-triggered CT, in identifying coronary calcification. MATERIALS AND METHODS: A total of 174 patients for whom CT was indicated for CAC scoring underwent nontriggered and triggered CT in a 64-channel multislice scanner, in a single session without a change in position. The images were interpreted by a radiologist with seven years of experience in thoracic and cardiovascular radiology. The measurement of coronary calcium was carried out by three methods: CAC score with dedicated software in nontriggered CT, CAC score with dedicated software in triggered CT, and visual analysis without dedicated software in nontriggered CT. RESULTS: In nontriggered CT, the CAC score presented an accuracy of 95.98% (95% CI: 91.93-98.04). The visual analysis showed an accuracy of 97.13% (95% CI: 93.45-98.77). CONCLUSION: Nontriggered CT showed excellent accuracy in the identification and exclusion of coronary calcification, either the CAC score was determined with dedicated software or through visual analysis.

12.
Radiol Bras ; 51(4): 218-224, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30202124

RESUMEN

OBJECTIVE: To analyze the prevalence of cystic lesions of the pancreas on imaging exams and their association with signs of malignancy risk. MATERIALS AND METHODS: This was an observational cross-sectional study, in which we evaluated 924 sequential computed tomography and magnetic resonance imaging scans of the abdomen. For all of the patients included in the study, we reviewed the demographic data available in the medical records and evaluated the images. RESULTS: Cysts were observed in 4.5% of patients, the prevalence of cysts being highest (7.6%) in patients over 60 years of age. Lesions were detected at higher rates on magnetic resonance imaging and in patients with pancreatic symptoms (6.1% and 42.9%, respectively). Signs of malignancy risk were observed in 26.3% of the patients, more frequently in those who were male and over 60 years of age. CONCLUSION: The prevalence of pancreatic cysts was 4.5%. Signs of malignancy risk were observed in 26.3% of the cystic neoplasms identified.

13.
Arq Bras Cardiol ; 110(3): 278-288, 2018 Mar.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-29694555

RESUMEN

Many non-invasive methods, such as imaging tests, have been developed aiming to add a contribution to existing studies in estimating patients' prognosis after myocardial injury. This prognosis is proportional to myocardial viability, which is evaluated in coronary artery disease and left ventricular dysfunction patients only. While myocardial viability represents the likelihood of a dysfunctional muscle (resulting from decreased oxygen supply for coronary artery obstruction), hibernation represents post-interventional functional recovery itself. This article proposes a review of pathophysiological basis of viability, diagnostic methods, prognosis and future perspectives of myocardial viability. An electronic bibliographic search for articles was performed in PubMed, Lilacs, Cochrane and Scielo databases, according to pre-established criteria. The studies showed the ability of many imaging techniques in detecting viable tissues in dysfunctional areas of left ventricle resulting from coronary artery injuries. These techniques can identify patients who may benefit from myocardial revascularization and indicate the most appropriate treatment.


Asunto(s)
Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/patología , Miocardio/patología , Miocitos Cardíacos/patología , Supervivencia Tisular/fisiología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/fisiopatología , Ecocardiografía/métodos , Corazón/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Infarto del Miocardio/fisiopatología , Revascularización Miocárdica , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Pronóstico , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/patología
14.
Radiol Bras ; 51(1): 13-19, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29559761

RESUMEN

OBJECTIVE: To compare an albumin-bound gadolinium chelate (gadofosveset trisodium) and an extracellular contrast agent (gadobenate dimeglumine), in terms of their effects on myocardial longitudinal (T1) relaxation time and partition coefficient. MATERIALS AND METHODS: Study subjects underwent two imaging sessions for T1 mapping at 3 tesla with a modified look-locker inversion recovery (MOLLI) pulse sequence to obtain one pre-contrast T1 map and two post-contrast T1 maps (mean 15 and 21 min, respectively). The partition coefficient was calculated as ΔR1myocardium /ΔR1blood , where R1 is 1/T1. RESULTS: A total of 252 myocardial and blood pool T1 values were obtained in 21 healthy subjects. After gadolinium administration, the myocardial T1 was longer for gadofosveset than for gadobenate, the mean difference between the two contrast agents being -7.6 ± 60 ms (p = 0.41). The inverse was true for the blood pool T1, which was longer for gadobenate than for gadofosveset, the mean difference being 56.5 ± 67 ms (p < 0.001). The partition coefficient (λ) was higher for gadobenate than gadofosveset (0.41 vs. 0.33), indicating slower blood pool washout for gadofosveset than for gadobenate. CONCLUSION: Myocardial T1 times did not differ significantly between gadobenate and gadofosveset. At typical clinical doses of the contrast agents, partition coefficients were significantly lower for the intravascular contrast agent than for the extravascular agent.

16.
Arq Bras Cardiol ; 108(5): 458-469, 2017 May.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-28591322

RESUMEN

The study of myocardial viability is of great importance in the orientation and management of patients requiring myocardial revascularization or angioplasty. The technique of delayed enhancement (DE) is accurate and has transformed the study of viability into an easy test, not only for the detection of fibrosis but also as a binary test detecting what is viable or not. On DE, fibrosis equal to or greater than 50% of the segmental area is considered as non-viable, whereas that below 50% is considered viable. During the same evaluation, cardiac magnetic resonance (CMR) may also use other techniques for functional and perfusion studies to obtain a global evaluation of ischemic heart disease. This study aims to highlight the current concepts and broadly emphasize the use of CMR as a method that over the last 20 years has become a reference in the detection of infarction and assessment of myocardial viability. Resumo O estudo de viabilidade miocárdica é de grande importância para a orientação e manejo de pacientes que necessitam de cirurgia de revascularização miocárdica ou angioplastia. A técnica de realce tardio (RT) é precisa e transformou o estudo de viabilidade em um teste fácil, não só para a detecção de fibrose, mas também como um modelo binário para a detecção do que é ou não é viável. Uma fibrose identificada pelo RT é considerada como não viável quando igual ou maior do que 50% da área segmentar e como viável quando menor que 50%. A ressonância magnética cardíaca (RMC) também pode lançar mão de outras técnicas para estudo funcional e de perfusão para uma avaliação global da doença isquêmica do coração no mesmo exame. Este estudo tem como objetivo destacar os conceitos atuais e enfatizar amplamente o uso da RMC como um método que nos últimos 20 anos se tornou referência na detecção de infarto e avaliação de viabilidade miocárdica.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Infarto del Miocardio/diagnóstico por imagen , Supervivencia Tisular/fisiología , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/fisiopatología , Medios de Contraste/normas , Humanos , Imagen por Resonancia Magnética/normas , Imagen por Resonancia Magnética/tendencias , Infarto del Miocardio/fisiopatología , Revascularización Miocárdica , Miocitos Cardíacos/patología
17.
Radiol. bras ; 55(3): 156-160, May-june 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1387084

RESUMEN

Abstract Objective: To compare the degree of coronary stenosis (≥ 50% luminal narrowing) determined by coronary computed tomography angiography (CCTA) with that determined by invasive coronary angiography (ICA), using segment-by-segment analysis. Materials and Methods: This was a retrospective study of the records of patients who underwent CCTA and ICA between January 2014 and June 2018 at a general hospital in Brazil. Receiver operating characteristic curve analysis was applied, and the areas under the curve were used in order to assess the overall accuracy of the methods. Results: The degree of coronary stenosis was evaluated in a total of 844 arterial segments. The diagnostic performance of CCTA was good, with a sensitivity of 82.3%, a specificity of 96.4%, and a negative predictive value of 97.7% (95% CI: 96.5-98.5). In the segment-by-segment analysis, CCTA had excellent accuracy for the left main coronary artery and for other segments. Conclusion: In clinical practice at general hospitals, CCTA appears to have diagnostic performance comparable to that of ICA.


Resumo Objetivo: O objetivo do estudo é comparar os graus de estenose coronariana (≥ 50% de redução luminal) determinados pela tomografia computadorizada e pelo cateterismo, utilizando uma análise segmento a segmento. Materiais e Métodos: Estudo retrospectivo conduzido em pacientes que foram submetidos a tomografia computadorizada e a cateterismo, de janeiro de 2014 a junho de 2018, em um hospital geral. A análise da curva característica de operação do receptor foi utilizada para a análise da acurácia. Resultados: Na avaliação dos vasos, em um total de 844 segmentos, o desempenho da tomografia computadorizada foi bom, com sensibilidade de 82,3%, especificidade de 96,4% e valor preditivo negativo de 97,7% (IC 95%: 96,5-98,5). Na análise segmento a segmento, o tronco da coronária esquerda, assim como outros segmentos, apresentaram excelente acurácia. Conclusão: A tomografia computadorizada mostrou bom desempenho diagnóstico quando comparada com o cateterismo na prática diária de um hospital geral.

18.
Arq Bras Cardiol ; 108(1): 21-30, 2017 Jan.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-27992035

RESUMEN

BACKGROUND: Amyloidosis is a disease caused by deposits of insoluble fibrils in extracellular spaces. The most common type of familial amyloidosis is mediated by mutation of transthyretin, especially Val30Met. Symptoms and ejection fraction decrease may occur in cardiac amyloidosis only in case of poor prognosis. Myocardial strain detected by two-dimensional speckle tracking echocardiography can indicate changes in myocardial function at early stages of the disease. OBJECTIVE: To determine the accuracy of left ventricular longitudinal strain by two-dimensional speckle tracking echocardiography in patients with familial amyloidosis caused by Val30Met transthyretin mutation. METHODS: Eighteen consecutive patients, carriers of transthyretin mutation, were evaluated by two-dimensional speckle tracking echocardiography, by which myocardial strain curves were obtained, following the American Society of Echocardiography recommendations. RESULTS: Patients were divided into three groups: 1- Val30Met with cardiac amyloidosis; 2-Val30Met with extracardiac amyloidosis; 3 - Val30Met without evidence of disease. As the three groups were compared by the Mann-Whitney test, we found a statistically significant difference between groups 1 and 2 in the mean longitudinal tension (p=0.01), mean basal longitudinal strain (p=0.014); in mean longitudinal tension and mean longitudinal strain between groups 1 and 3 (p=0.005); and in the ratio of longitudinal strain of apical septum segment to longitudinal strain of basal septum (p=0.041) between groups 2 and 3. CONCLUSION: Left ventricular longitudinal strain detected by two-dimensional speckle tracking echocardiography is able to diagnose left ventricular dysfunction in early stages of familial amyloidosis caused by transthyretin Val30Met mutation.


Asunto(s)
Neuropatías Amiloides Familiares/diagnóstico por imagen , Cardiomiopatía Dilatada/diagnóstico por imagen , Ecocardiografía/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adulto , Neuropatías Amiloides Familiares/genética , Neuropatías Amiloides Familiares/fisiopatología , Cardiomiopatía Dilatada/fisiopatología , Estudios de Casos y Controles , Estudios Transversales , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Prealbúmina/genética , Valores de Referencia , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Volumen Sistólico , Disfunción Ventricular Izquierda/fisiopatología
19.
Arq Bras Cardiol ; 107(4): 365-374, 2016 Oct.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-27437867

RESUMEN

Half the patients with coronary artery disease present with sudden death - or acute infarction as first symptom, making early diagnosis pivotal. Myocardial perfusion scintigraphy is frequently used in the assessment of these patients, but it does not detect the disease without flow restriction, exposes the patient to high levels of radiation and is costly. On the other hand, with less radiological exposure, calcium score is directly correlated to the presence and extension of coronary atherosclerosis, and also to the risk of cardiovascular events. Even though calcium score is a tried-and-true method for stratification of asymptomatic patients, its use is still reduced in this context, since current guidelines are contradictory to its use on symptomatic diseases. The aim of this review is to identify, on patients under investigation for coronary artery disease, the main evidence of the use of calcium score associated with functional evaluation and scintigraphy.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Medición de Riesgo/métodos , Tomografía Computarizada por Rayos X/métodos , Calcificación Vascular/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Humanos , Pronóstico , Factores de Riesgo
20.
Radiol Bras ; 49(1): 26-34, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26929458

RESUMEN

Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI) and cardiac computed tomography (CCT) are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complementarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies.


A cardiomiopatia isquêmica é um dos principais problemas de saúde no mundo, representando significativa parcela da mortalidade. A ressonância magnética cardíaca (RMC) e a tomografia computadorizada cardíaca (TCC) são métodos de imagem não invasivos úteis no diagnóstico da doença arterial coronariana e também podem auxiliar no rastreamento de indivíduos com fatores de risco para o desenvolvimento de cardiomiopatia induzida por isquemia/infarto. Os avanços tecnológicos da RMC e da TCC contribuíram para o surgimento de diversas indicações clínicas para aplicação desses métodos de imagem de forma complementar a outros exames, principalmente quando estes se mostram inconclusivos. A RMC e a TCC apresentam acurácia semelhante aos demais métodos de imagem, poucas contraindicações absolutas e mínimos riscos de efeitos adversos, o que os fortalecem como ferramentas seguras no manejo dos pacientes. O presente estudo tem por objetivo descrever o papel da RMC e da TCC no diagnóstico das cardiomiopatias isquêmicas.

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