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@#Objective To explore the relationship between myocardial viability in patients with coronary artery disease who underwent elective coronary artery bypass grafting (CABG) and early application of intra-aortic balloon pump (IABP) after coronary revascularization, and to provide relevant clinical reference for the pre-implantation of 16G single-lumen catheter in the femoral artery of high-risk patients to facilitate the addition of IABP after operation. Methods This retrospective study included 521 patients (414 males and 107 females, aged 62.50±8.82 years) who underwent positron emission tomography (PET)-computed tomography (CT) perfusion-metabolism imaging prior to CABG surgery in our institution from December 2015 to August 2020. The myocardial viability information and left ventricular functional parameters were measured, including the proportion of non-viable myocardium (perfusion-metabolic imaging match), hibernating myocardium (perfusion-metabolic imaging mismatch) and dysfunctional myocardium (non-viable+viable myocardium), left ventricular ejection fraction, left ventricular end-diastolic volume and left ventricular end-systolic volume (LVESV). The patients were divided into an IABP group and a non-IABP group according to whether they received IABP treatment after revascularization. The clinical data were reviewed and compared to explore significant impact factors between the two groups. And the multivariate logistic regression analysis was performed to investigate the correlation between preoperative myocardial viability and early use of IABP after CABG. Results In multivariate logistic regression analysis, the amount of non-viable, dysfunctional myocardium and LVESV value were identified as the independent predictors for the probability of IABP use in the initial postoperative period. Receiver operating characteristic analysis showed that 9.5% non-viable myocardium, 19.5% dysfunctional myocardium, and LVESV of 114.5 mL were the optimal cutoff for predicting early IABP implantation during CABG. Conclusion The myocardial survival status displayed by preoperative PET-CT myocardial perfusion-metabolism imaging can predict the possibility of applying IABP in CABG perioperative period. In addition to routine pre-anesthesia assessment, anesthesiologists can conduct risk stratification assessment for patients with CABG according to the results of preoperative myocardial viability imaging, which is of great significance to ensure the perioperative safety of high-risk patients with CABG.
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RESUMEN Introducción: Las técnicas de inteligencia artificial han demostrado tener un gran potencial en el área de la cardiología, especialmente para identificar patrones imperceptibles para el ser humano. En este sentido, dichas técnicas parecen ser las adecuadas para identificar patrones en la textura del miocardio con el objetivo de identificar y cuantificar la fibrosis. Objetivos: Proponer un nuevo método de inteligencia artificial para identificar fibrosis en imágenes cine de resonancia cardíaca. Materiales y métodos: Se realizó un estudio retrospectivo observacional en 75 sujetos del Sanatorio San Carlos de Bariloche. El método propuesto analiza la textura del miocardio en las imágenes cine CMR (resonancia magnética cardíaca) mediante el uso de una red neuronal convolucional que determinar el daño local del tejido miocárdico. Resultados: Se observó una precisión del 89% para cuantificar el daño tisular local en el conjunto de datos de validación y de un 70% para el conjunto de prueba. Además, el análisis cualitativo realizado muestra una alta correlación espacial en la localización de la lesión. Conclusiones: El método propuesto permite identificar espacialmente la fibrosis únicamente utilizando la información de los estudios de cine de resonancia magnética nuclear, mostrando el potencial de la técnica propuesta para cuantificar la viabilidad miocárdica en un futuro o estudiar la etiología de las lesiones.
ABSTRACT Background: Artificial intelligence techniques have demonstrated great potential in cardiology, especially to detect imperceptible patterns for the human eye. In this sense, these techniques seem to be adequate to identify patterns in the myocardial texture which could lead to characterize and quantify fibrosis. Purpose: The aim of this study was to postulate a new artificial intelligence method to identify fibrosis in cine cardiac magnetic resonance (CMR) imaging. Methods: A retrospective observational study was carried out in a population of 75 subjects from a clinical center of San Carlos de Bariloche. The proposed method analyzes the myocardial texture in cine CMR images using a convolutional neural network to determine local myocardial tissue damage. Results: An accuracy of 89% for quantifying local tissue damage was observed for the validation data set and 70% for the test set. In addition, the qualitative analysis showed a high spatial correlation in lesion location. Conclusions: The postulated method enables to spatially identify fibrosis using only the information from cine nuclear magnetic resonance studies, demonstrating the potential of this technique to quantify myocardial viability in the future or to study the etiology of lesions.
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Embora a avaliação da viabilidade miocárdica seja comum na prática do cardiologista, muitos médicos têm dúvidas a respeito dos resultados dos métodos diagnósticos. A medicina nuclear tem papel importante nos estudos de viabilidade, mas os laudos precisam ser interpretados num contexto clínico e fisiopatológico. Este artigo teve o objetivo de revisar a origem e a evolução do conceito da viabilidade miocárdica. São expostos os métodos diagnósticos com ênfase na medicina nuclear com uma explicação funcional sobre cada tipo de exame. A partir disso, são mostradas imagens como exemplos e é proposta uma maneira de atuar nesses casos baseada na clínica, na porcentagem de miocárdio acometido e na topografia das lesões coronarianas (proximais ou distais). (AU)
Although assessing myocardial viability is a common cardiology practice, many physicians question the results of diagnostic methods. Nuclear medicine plays an important role in viability studies, but the reports require interpretation in a clinical and pathophysiological context. this article was aimed at reviewing the origin and evolution of myocardial viability. Here we present diagnostic methods by emphasizing nuclear medicine and provide a functional explanation of each test type using example images. We also propose how to act in these cases based on clinic examination findings, the percentage of affected myocardium, and coronary lesion topography (proximal or distal).(AU)
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Humains , Échocardiographie/méthodes , Sidération myocardique/diagnostic , Sidération myocardique/physiopathologie , Dysfonction ventriculaire gauche/thérapie , Médecine nucléaire/instrumentation , Rubidium/administration et posologie , Thallium/administration et posologie , Tomographie par émission monophotonique/méthodes , Diagnostic Clinique , Échocardiographie de stress/méthodes , Tomographie par émission de positons/méthodes , Dobutamine/administration et posologie , Revascularisation myocardique/méthodesRésumé
@#Objective To explore the predictive value of myocardial vitality in the improvement of cardiac function after coronary artery bypass grafting (CABG) in patients with ischemic heart failure. Methods From December 8, 2015 to November 12, 2018, 46 patients with ischemic heart failure who underwent CABG operation alone were collected retrospectively. There were 41 males and 5 females with an average age of 60.4±8.0 years. The myocardial vitality and number of different types of myocardium were measured. The clinical data of patients in the left ventricular ejection fraction (LVEF) improvement group (≥5%) and non-improvement group (<5%) were compared and analyzed. The correlation between each index and LVEF improvement was analyzed by logistic multivariate regression analysis, and the boundary value of hibernating myocardium between LVEF improvement and non-improvement was obtained by receiver operating characteristic (ROC) curve. Results There were significant differences in the number of hibernating myocardium (15.0%±12.3% vs. 4.3%±4.5%, P=0.000), the number of normal myocardium (74.7%±13.7% vs. 82.4%±8.6%, P=0.027), and cardiac function classification (NYHA) development (−0.7±0.7 vs. −0.3±0.5, P=0.047) between the two groups, but there was no significant difference in other indexes between the two groups (P>0.05). Logistic regression analysis showed that the number of hibernating myocardium was an independent factor affecting the improvement of LVEF after CABG in patients with ischemic heart failure (OR=1.366, 95%CI 1.033-1.807, P=0.029). The ROC curve showed that the threshold value, sensitivity and specificity of hibernating myocardium were 15.0%, 43.8% and 100.0%, respectively. Conclusion The percentage of hibernating myocardium to left ventricular wall area ≥15.0% can accurately predict the improvement of LVEF in patients with ischemic heart failure after CABG. Preoperative myocardial vitality assessment has important diagnostic value in predicting the improvement of cardiac function in patients with ischemic heart failure after simple CABG.
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A 48-year old man consulted a doctor at a nearby medical clinic due to dyspnea and increased body mass which he began to experience in October, 2011. Further evaluation revealed the presence of three-vessel severe coronary artery disease, poor left ventricular function, and mitral valve regurgitation. Transthoracic echocardiography showed anterior wall asynergy and left ventricular enlargement. Reconstruction of the left ventricle was contemplated during the preoperative evaluation. The patient underwent hemodialysis for chronic renal failure prior to admission. Generally, delayed gadolinium-enhanced MRI is used for cardiac viability assessment. However, gadolinium is contraindicated in a patient with chronic renal failure owing to the risk of development of nephrogenic systemic fibrosis. Thus, gadolinium-enhanced MRI is contraindicated in the patient. Instead, we used fluorodeoxyglucose-positron emission tomography (FDG-PET) computed tomography (CT) to assess myocardial viability. Consequently, viability was assessed except for a part of the apical electrode in the left anterior descending artery territory. Subsequently, revascularization and mitral valve annuloplasty with coronary artery bypass grafting of five vessels were performed in January, 2012 without left ventricular reconstruction. A left ventricular assist device was used postoperatively, from which he was later weaned. The outcome was good because post-operative left ventriculography revealed improvement in left ventricular wall motion. This case is presented including bibliographical comments on the effectiveness of FDG PET-CT for assessment of myocardial viability.
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Introducción. La revascularización miocárdica es el tratamiento de elección en pacientes con disfunción sistólica isquémica. Objetivos. Determinar las variables asociadas al restablecimiento de la fracción de eyección en pacientes con disfunción ventricular isquémica sometidos a revascularización miocárdica. Materiales y métodos. Se incluyeron pacientes con fracción de eyección del ventrículo izquierdo (FEVI) <50% sometidos a cirugía por anatomía coronaria y seguimiento ecocardiográfico ≥6 meses. Se analizaron variables relacionadas con la mejoría de la FEVI (>5%). Resultados. Se incluyeron 95 pacientes, el 91,6% masculino, edad media de 63 años, 40% diabéticos, 27% con infarto previo y FEVI de 36 ± 6%. Se evaluó viabilidad en el 78%. Durante el postoperatorio, el 12% presentó isquemia perioperatoria y el 28% bajo gasto cardíaco. Tras análisis multivariado, la viabilidad y la ausencia de isquemia perioperatoria fueron predictores independientes de la mejoría de la FEVI. Conclusión. La viabilidad y la falta de isquemia durante el perioperatorio se asociaron con mejoría de la FEVI durante el postoperatorio alejado.
Introduction. Myocardial revascularization is considered the best option for patients with ischemic left ventricular dysfunction. Objectives. To identify associated variables with the improvement of ejection fraction after surgical revascularization (CABG). Materials and methods. We included patients with ejection fraction (EF) <50% who underwent to CABG. We examine preoperative predictors of ventricular functional recovery. Results. We included 95 patients, 91.6% male, mean age of 63 years, 40% diabetes, 27% with prior myocardial infarction and EF average of 36 ± 6%. Myocardial viability was evaluated in 78%. After surgery, 12% presented postoperative ischemia and 28% low cardiac output syndrome. In a multivariate analysis, myocardial viability and absence of postoperative ischemia were both predictors of improvement in EF. Conclusion. Myocardial viability and absence of postoperative ischemia were both associated with improvement in post operative EF.
Introdução. A revascularização do miocárdio é considerada a melhor opção para pacientes com disfunção ventricular esquerda isquêmica. Objetivos. Determinar as variáveis associadas à melhora da fração de ejeção (FE) após a revascularização cirúrgica (CRM). Materiais e métodos. Foram incluídos pacientes com FE <50% submetidos à CRM de acordo com a anatomia coronariana e ecocardiográfica ≥6 meses. Foram analisadas as variáveis relacionadas à melhora da FE (>5%). Resultados. Foram incluídos 95 pacientes, 91,6% do sexo masculino, idade média 63 anos, 40% eram diabéticos, 27% com infarto do miocárdio prévio e FE média de 36 ± 6%. A viabilidade miocárdica foi avaliada em 78%. Após a cirurgia, 12% apresentaram isquemia peri-operatória e 28% síndrome de baixo débito cardíaco. Em uma análise multivariada, a viabilidade miocárdica e ausência de isquemia peri-operatória foram ambos preditores de melhora na FE. Conclusão. A viabilidade miocárdica e ausência de isquemia peri-operatória foram ambos associados com a melhora da FE durante o pós-operatório.
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Objective: To investigate the 18F-FDG PET myocardial scintigraphy and Coronary CT angiography (CTA) combination improve coronary heart disease clinical diagnosis level, and the diagnosis of coronary heart disease treatment technology of standardization for clinical application. Methods:The use of positron radionuclide drug 18F-fluorodeoxyglucose (18F-FDG) was made in 35 patients with myocardial metabolic imaging of coronary arteries and CTA examination, 20 patients with myocardial infarction patients, the FDG PET myocardial scintigraphy and coronary artery CTA combine examination results and confirmed case comparison of results. Results: 18F-FDG PETmyocardial scintigraphy and coronary artery CTA combination in the diagnosis of coronary heart disease, sensitivity and specificity of 100%and 96%. Conclusion: 18F-FDG PET data and coronary artery CTA precision data fusion, the fusion image is accurate, can not only provide clinicians reflect coronary artery anatomy indicators, can also provide reflect myocardial pathological physiology and metabolism index, to verify and supplement each other between the indicators.
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Objective To investigate the role of three-dimensional speckle tracking echocardiography (3D-STE) in providing a novel approach to assessing myocardial viability in patients with myocardial infarction (MI).Methods The subjects from the Department of Cardiology and the Department of Cardiac Surgery admitted from April 2010 through December 2012 were diagnosed as MI by electrocardiogram,myocardial enzymes and angiography.The clear imaging of angiography was selected out and collected.All patients had different degrees of segmental wall motion abnormalities,and some already had percutaneous transluminal coronary angioplasty and coronary stenting or coronary artery bypass grafting.Patients with diabetes,heart disease and severe valvular disease of heart were excluded.A total of 45 MI patients were checked with routine echocardiography,two-dimensional speckle tracking echocardiography (2D-STE) and 3D-STE.Then,radionuclide myocardial perfusion/metabolic imaging was served as a golden standard to distinguish the viable from nonviable myocardium in each patient within a day.In order to determine the most sensitivity and specificity threshold values of circumferential peak-systolic strain (Cs),longitudinal peak-systolic strain (Ls),radial peak-systolic strain (Rs),3D strain and area strain for viability detection from 3D-STE,the receiver operating characteristic curve was used to investigate the sensitivity and specificity of the detection of viable myocardium with strain parameters in the study.Comparisons between viable and non-viable groups were carried out with t test.Data were expressed as the mean value ± standard deviation (-x ± s).Results The ventricular wall motion abnormality by visual assessment was observed in 368 segments from 720 segments in 45 patients.Furthermore,204 segments were confirmed to be viable by radionuclide myocardial perfusion/metabolic imaging whereas the rest 164 segments were identified as nonviable among 368 abnormal segments.There were no significant differences in circumferential peaksystolic strain (Cs),longitudinal peak-systolic strain (Ls) and radial peak-systolic strain (Rs) by 2D-STE between viable and nonviable group.Compared with those in viable group,there wasn' t any difference in Cs,but Rs and Ls decreased significantly by 3D-STE in nonviable group.The 3D strain and area strain in absolute value decreased in nonviable group compared with viable group.According to 3D-STE,when Rs higher than 11.1%,the sensitivity was 95.1% and the specificity was 53.4% for identification of viable myocardium,whereas Ls higher than 14.3% resulted in sensitivity of 65.2% and a specificity of 65.7%.Besides,3D strain higher than 17.4% had a sensitivity of 70.6% and a specificity of 77.2% for detection of viable myocardium,while area strain higher than 23.2% allowed a sensitivity of 91.5% and a specificity of 78.8%.Conclusions The 3D-STE might have potential reliability of myocardial viability detection in the patients with left ventricular dysfunction after MI.
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Objective To retrospectively study 50 children with anomalous origin of the left coronary artery from the pulmonary artery(ALCAPA) and find the simple and practical indexes that may predict myocardial viability and the possible risk factors that may affect the choice of operation and the recovery after surgery.Methods A retrospective study was performed in 50 children with ALCAPA [29 male,21 female,aged from 4 months to 18 years,average (4.49 ±4.30) years] between Apr.1999 and Mar.2013.The preoperative examination included electrocardiogram (ECG),echocardiography,chest X-ray,mutislice spiral computerized tomography (MSCT),angiocardiography et al.Follow-up data were obtained by reviewing the records made in out-patient and recent telephone call.According to myocardial 18F-FDG imaging,the extent of myocardial viability of 15 patients with ALCAPA was classified into 4 grades.0 normal myocardial; 1 viable myocardial ;2 partial viable myocardial;3 myocardial infarction.Meanwhile,the global clinical scores were calculated and divided into 10 levels according to the deviations of clinical manifestations which included abnormal Q waves,left ventricular ejection fraction (LVEF),left ventricular end-diastolic dimension (LVED),cardiothoracic ratio(CTR),intercoronary collaterals(ICC),mitral regurgitation(MR) and aneurysm.The relationship of the extent of myocardial viability and clinical features were studied.All patients with ALCAPA were classified into groups by the global clinical scores and the preoperative,perioperative and post operative clinical manifestations were compared among groups.Results The extent of myocardial viability was related well to the global clinical scores (r =0.936,P <0.001),LVEF(r =0.783,P < 0.001),CTR (r =0.770,P < 0.002),abnormal Q waves (r =0.667,P < 0.01) and LVED (r =0.637,P < 0.02),but was not related to age,MR and ICC (r =-0.206,-0.268,-0.342,all P > 0.05).The results showed that grade 0-1 equaled scores 0-3,grade 2 equaled scores 3-5,grade 3 equaled scores > 5.Chil-dren with less viable myocardium had more severe clinical symptoms.Among abnormal Q waves,LVEF < 50%,CTR >0.65,ICC dysplasia,median to severe MR and the global clinical scores > 3,the global clinical scores > 3 and LVEF <50% showed a good predict of myocardial infarction.The preoperative,perioperative and post operative clinical manifestations were compared between 2 groups divided by the global clinical scores (group A,scores ≤ 3 and group B,scores >3) in all patients.More infants and toddlers,abnormal Q waves,ICC dysplasia,RCA/AO <0.2,larger CTR and lower LVEF were found in group B than those in group A.The time of cross-clamp and CPB was not different between the 2 groups,but the postoperative ventilation time and postoperative ICU stay were longer in group B than in group A.Fortyseven patients underwent operation and there were no operative deaths.One infant with scores 9 died while waiting heart transplantation.Follow-ups from 1 to 168 months were conducted in 38 patients(80.9%,38/47 cases) and 1 patient with ligation of the left coronary artery (LCA) had a sudden death after 8 months of surgery.All patients had gotten smaller LVED after surgery.Nineteen patients had mild MR and 3 patients had mild supravalvular pulmonary stenosis in following-up.Of the 16 patients with LVEF < 50%,14 had a recovery of LVEF,2 patients still had LVEF < 50%.Conclusions In children with ALCAPA,the extent of myocardial viability evaluated by myocardial 18 F-FDG imaging is related closely to the preoperative clinical manifestations.The global clinical scores > 3 and LVEF < 50% have a good predict of myocardial infarction.Even in young children with severely depressed left ventricular function,higher global clinical scores and more myocardial infarction,median and long-term follow-ups showed satisfactory recovery of cardiac function after successful restoration of a dual coronary arterial system.
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Objetivos: Estandarizar un protocolo de adquisición para el estudio del metabolismo glucolítico, oxidativo y de perfusión miocárdicos en un modelo de rata. Métodos: Se realizaron estudios con los tres principales radiotrazadores usados para evaluar la función cardiaca: 18F-FDG para evaluar el metabolismo glucolítico en tres protocolos distintos; 1-11C-acetato para el metabolismo oxidativo y 13NH3 para la perfusión cardiaca. (18F-FDG)- cinco ratas Wistar macho en tres diferentes protocolos: con acceso a libre demanda de comida y agua; con ayuno de ocho horas y con ayuno de ocho horas más carga oral de glucosa al 50%. Se adquirieron imágenes del área torácica durante 30 minutos mediante microPET; 30 y 60 minutos post-administración de 370 - 555 MBq de 18F-FDG vía IP. (1-11C-acetato)- Se estudiaron ocho ratas. Cuatro estudios estáticos de 30 minutos y cuatro adquisiciones dinámicas de 30 minutos tras administración de 370 - 555 MBq de1-11C-acetato por vena caudal.(13NH3)- 10 estudios estáticos de 15 minutos después de una dosis IV de 370 - 555 MBq de 13NH3, bajo anestesia inhalada con isofluorano a 1.5% a 2%. Se realizó análisis comparativo y cualitativo de todas las imágenes obtenidas por dos médicos especialistas en el área y un análisis semi-cuantitativo mediante reconstrucciones 3D y selección de ROIs con el programa AMIDE en el caso de 18F-FDG. Resultados: Se determinó que las mejores imágenes para fines de evaluación metabólica del miocardio fueron las correspondientes a los 60 minutos post-administración de la 18F-FDG del protocolo sin ayuno. Se visualizó sin problemas el miocardio de rata de las imágenes estáticas con 1-11C-acetato, y mediante adquisición dinámica, se pudo apreciar la perfusión miocárdica. Las imágenes con 13NH3 permitieron observar una distribución homogénea del radiotrazador en los diferentes segmentos del ventrículo izquierdo en el eje corto, eje largo vertical y eje largo horizontal. Conclusiones: Se logró la estandarización de protocolos de adquisición de imágenes de los tres principales radiotrazadores utilizados para el estudio del metabolismo y perfusión cardiacos, en un modelo animal. Es factible establecer un protocolo válido para la valoración de perfusión, metabolismo glucolítico y oxidativo miocárdicos, con el fin de utilizarlo como punto de referencia para la evaluación de terapias génica, farmacológica o quirúrgica a nivel experimental.
Objective: To standardize an acquisition protocol for the study of myocardial glucolitic and oxidative metabolism and perfusion in a rat model. Methods: Studies were carried out with the three main radiopharmaceuticals used to assess heart function:[18F]-FDG for glucolitic metabolism; [1-11C]-acetate for oxidative metabolism and [13N]-NH3for myocardial perfusion.[18F]-FDG -Five Wistar adult male rats were studied in three different protocols: non-fasting group, fasting group,8 h before the study with water provided ad libitum, and a fasting group by the same time receiving an oral 50%-glucose solution. Thirty-minute scans were performed with a microPET Focus 120, 30 and 60 min after the administration of 370-555 MBq 18F-FDG. [1-11C]-Acetate -Eight rats were studied. Four static and four dynamic 30 min acquisitions after a 370-555 MBq of [1-11C]-acetate caudal vein administration.[13N]-NH3-Ten static studies were acquired 15 min post-administration of 370555 MBqof13NH3, under 1.5-2% isofluorane anesthesia. Comparative and visual analyses were performed by two experts in the field. A semi-quantitative analysis was performed using 3D reconstructions and ROI selections with AMIDE software. Results: The best images were those obtained from the non-fasting group, especially those taken at 60 min after the [18F]-FDG administration. High quality myocardial, static images were obtained with [1-11C]-acetate, and the dynamic acquisitions allowed the identification of myocardial perfusion. The 13NH3images showed a homogeneous distribution of the radiotracer in different segments of the short, long and horizontal axes in the left ventricle. Conclusions: It is possible to standardize the microPET acquisition protocols for the three main radiopharmaceuticals to evaluate the heart function in a rat model. It is feasible to establish a valid protocol for measuring glucolitic and oxidative myocardial metabolism and perfusion for gene, drug or surgical therapy assessment.
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Animaux , Mâle , Rats , Acétates , Circulation coronarienne , Carbone , Myocarde/métabolisme , Radio-isotopes de l'azote , Tomographie par émission de positons , Radiopharmaceutiques , Ammoniac , Modèles animaux , Tomographie par émission de positons/méthodes , Rat WistarRésumé
The clinical utility of radiotracer study of heart in nuclear cardiology must always be considered in the of context of other cardiac diagnostic procedures, including ECG, Echo, ETT,CAG and cardiac enzymes or serum cardiac protein. So one should not be a hop cardiologist. Two modalities in Nuclear Cardiology: 1).Radionuclide Angiography (RNA) or Radionuclide Ventriculography. 2).Myocardial Perfusion Imaging (MPI). Radionuclide Angiography (RNA) or Radionuclide Ventriculography: This procedure is designed to provide measurement of LVEF in patient of coronary artery disease, valvular heart disease or cardiomyopathy. In our setting we determine EF from MPI, so Radionuclide Angiography routinely not do in many centre of world including NICVD, Dhaka. Myocardial Perfusion Imaging (MPI): MPI, more specifically myocardial perfusion single photon emission computed tomography (SPECT) is a nice tool for the noninvasive assessment of myocardial perfusion, ejection fraction, wall motion, and wall thickness. Why not perform cardiac catheterization and coronary angiography in all patients suspected of having coronary artery diseases? The contrast coronary angiogram displays the anatomic extent of epicardial coronary artery disease, the severity of luminal narrowing, and the number of diseased vessels. Stress radionuclide myocardial perfusion imaging, on the other hand, displays the downstream functional consequences of epicardial coronary artery disease in the myocardium. It also may visualize the regional effects of micro vascular endothelial dysfunction and impairment of regional coronary flow reserve. Application of MPI: The diagnosis of coronary artery disease remain common application of MPI ,but it is increasingly being used for the diagnosis of acute MI, risk stratification after infarction, and assessment of viable myocardium versus scar in patients in chronic coronary artery disease.
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Objective To explore the relationship between the index of SPECT myocardial viability teat of the left ventricle and long-term cardiovascular adverse events following the coronary artery bypass graft.Methods Clinical data were selected from the coronary-heart-disease patients with CABG and the isotopic SPECT test of myocardial viability prior to the operation in the Fuwai Cardiovascular Hospital,the Chinese Academy of Medical Science from January 1,1999 to December 31,2005.Total 709 patients were included in this study.Regular follow-up in patients was performed following operation.Investigate the nuclear medicine documents of the patients above;make the semi-quantitative scores of myocardial viability prior to operation by the 17-segment method of ventricle.Through the COX multi-factor analysis of the statistical methods to explore the relationship between the index of the myocardial viability and the long-term cardiac adverse events selected in advance.Results The mean duration of follow-up was(3.43±2.42)years.The COX multi-analysis revealed that the total score of left ventricular myocardial viability is the independent impact factors for long term cardiac death,long terrm re-hospitalization rate and long term composite end points events.The cut off values of total score of left ventricular myocardial viability for long term cardiac death,long term re-hospitalization rate and long term composite end points events is 15,9,13 respectively.Conclusion The total score of left ventricular myocardial viability of SPECT is independently associated with long-term events,and the cut values of myocardial viability total score for long-term cardiac death,re-hospitalization and composite MACE events are 15,9,and 13 respectively.For the groups with total scores above and below the cut off values,there is significant difference of long term cardiac events risk between groups.
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La insuficiencia cardíaca es la primera causa de discapacidad y muerte, que afecta a más de cinco millones de individuos en los Estados Unidos. La morbilidad de esta patología está dada por hospitalizaciones recurrentes, lo que eleva los costos en salud. Los nuevos tratamientos para la insuficiencia cardíaca han mejorado los resultados; pero a pesar de ello, la mortalidad continúa siendo elevada. Debido a que el riesgo operatorio de la cirugía de revascularización es alto en los pacientes con disfunción ventricular izquierda y el beneficio de la misma no siempre está asegurado, la estratificación del riesgo no-invasiva para definir la existencia de miocardio viable es esencial. La detección de miocardio viable en pacientes con enfermedad coronaria y disfunción ventricular izquierda (con estudios de perfusión SPECT o con imágenes metabólica con FDG) es considerada una recomendación clase I (nivel de evidencia B). La disfunción ventricular izquierda en la cardiopatía isquémica puede ser debida a tejido fibrótico, necrótico o a tejido viable que puede estar atontado o hibernado. Aproximadamente el 70% de la causa de insuficiencia cardíaca es la enfermedad coronaria, y un número significativo de estos pacientes tienen miocardio hibernado.
Chronic heart failure (CHF) is a leading cause of death and disability affecting more than 5 million individuals in the United States. The morbidity of CHF includes recurrent hospitalizations, which also drive up health care costs. New therapies for CHF have improved outcomes, but mortality remains high. Because perioperative risk for revascularization is higher in patients who have reduced systolic dysfunction and the benefit may not always be certain; noninvasive risk stratification for patients who have viable myocardium becomes essential. Detection of myocardial viability in patients who have coronary artery disease (CAD) and left ventricular (LV) systolic dysfunction (with either MPI or FDG imaging) is generally regarded as a class I recommendation (level B evidence). LV dysfunction in ischemic heart disease may be due to prior infarct and scar or viable tissue that can be stunned, hibernating, or normal remodeled myocardium. Approximately 70% of CHF is secondary to CAD and a significant number of these patients have myocardial hibernation.
A insuficiência cardíaca é a primeira causa de discapacidade e morte que afeta a mais de cinco milhões de indivíduos nos Estados Unidos. A morbilidade desta patologia está dada por hospitalizações recorrentes, o que eleva os custos em saúde. Os novos tratamentos para a insuficiência cardíaca têm melhorado os resultados; apesar disso, a mortalidade continua sendo elevada. Devido ao risco operatório da cirurgia de revascularização ser alto nos pacientes com disfunção ventricular esquerda e o benefício da mesma nem sempre está assegurado, a estratificação do risco não-invasivo para definir a existência de um miocárdio viável é essencial. A detecção de um miocárdio viável em pacientes com doença coronária e disfunção ventricular esquerda (com estudos de perfusão SPECT ou com imagens metabólica com FDG) é considerada uma recomendação classe I (nível de evidência B). A disfunção ventricular esquerda na cardiopatia isquêmica pode ser devida ao tecido fibrótico, necrótico ou ao tecido viável que pode estar atordoado ou hibernado. Aproximadamente 70% da causa de insuficiência cardíaca é a doença coronária, e um número significativo destes pacientes têm miocárdio hibernado.
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Objective To seek a new method to identify viability of myocardium by adenosine stress echocardiography combined with quantitative tissue velocity imaging(QTVI)and tissue tracking(TT).Methods Fifteen healthy canines were selected to establish the models of acute myocardial infarction and reperfusion by ligating anterior descending branch of coronary artery for 90 minutes and then releasing the artery to get reperfusion.After reperfusion.peak velocity in systole(Vs),peak velocity in isovolumic contraction(VIVC)and the displacement in systole(Ds)were measured on anterior wall and anterior septum at baseline.The 2,3,5-triphenyl tetrazolium chloride(TTC)staining was set as a"gold standard"for defining the viable and non-viable groups.The sensitivity and specificity of assessing myocardial viability were determined with QTVI and TT.Comparison of variables between viable and non-viable group was made by using t test.One way analysis of variance and LSD-t test were used to estimate the significance of differences in different states.Results Compared with baseline,Vs,VIVC and Ds decreased significantly(P<0.01)after reperfusion in both viable and non-viable group.After administration of adenosine,Vs and Ds increased(P<0.05),but VIVC didn't change significantly compared with that before administration of adenosine in viable group(P>0.05).Variables in non-viable group didn't change significantly after administration of adenosine(P>0.05).By receiver operating characteristic(ROC)analysis for predicting myocardial viability,when a cutoff value of △Vs(%)rate was 17.9,the sensitivity and the specificity was 78.6%and 81.1%,respectively,and when the cutoff value of △Ds(%)rate was 18.4,the sensitivity and the specificity was 75.0%,83.6%,respectively.Combined △Vs(%)with △Ds(%),the sensitivity and specificity to prediction of myocardium viability could reach 94.6%and 68.0%,respectively.Conclusions When the viability of myocardium after myocardial infarction is assessed by using the method of adenosine stress echocardiography with QTVI and TT,the sensitivity and the specificity are greatly enhanced.
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La toma de decisiones en la enfermedad coronaria debe basarse en datos clínicos, evidencia de isquemia inducible, función ventricular izquierda y anatomía coronaria; sin embargo, en pacientes con antecedente de infarto de miocardio extenso y disfunción ventricular izquierda severa en quienes no se ha demostrado isquemia residual, la viabilidad miocárdica adquiere gran relevancia clínica, pues es el hallazgo que nos indicará si es necesaria y beneficiosa la revascularización. La viabilidad miocárdica nos permitirá predecir con gran exactitud la recuperación del miocardio disfuncionante como la mejoría de la sobrevida y la calidad de vida de los pacientes, luego de la revascularización. Dentro del área de cardiología nuclear, el estudio más sensible para la detección de miocardio viable es la tomografía por emisión de positrones con flúor 18 desoxi-glucosa.
Revascularization in coronary artery disease should be based on clinical data, evidence of inducible ischemia, left ventricular function and coronary anatomy; however in patients with history of extended acute myocardial infarction and severe left ventricular dysfunction in whom no residual ischemia has been demonstrated, myocardial viability acquires great clinical relevance because it´s presence will indicate us if it is necessary and beneficial the revascularization. Myocardial viability will allow us to predict with great accuracy the recovery of the dysfunctional myocardium, like the improvement of survival and the quality of the patients life after the revascularization. Inside the area of nuclear cardiology, the most sensitive study for detection of viable myocardium is the Positron Emission Tomography with Fluorine 18 Deoxi-glucose.
A tomada de decisões na doença coronária deve basear-se em dados clínicos, evidência de isquemia induzível, função ventricular esquerda e anatomia coronária; entretanto, nos pacientes com antecedente de enfarto de miocárdio extenso e disfunção ventricular esquerda severa em quem não se demonstrou isquemia residual, a viabilidade miocárdica adquire uma grande relevância clínica, pois é o achado que nos indicará se a revascularização é necessária e benéfica. A viabilidade miocárdica nos permitirá predizer a recuperação do miocárdio disfuncionante com grande exatidão assim como a melhora da sobrevida e da qualidade de vida dos pacientes, após a revascularização. Dentro da área da cardiologia nuclear, o estudo mais sensível para a detecção de um miocárdio viável é a tomografia por emissão de pósitrons com flúor 18 desoxi-glicose.
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Humains , Tomographie par émission monophotonique , Maladie coronarienne , Tomographie par émission de positonsRésumé
Obiective To compare the sensitivity and specificity of strain imaging(SI)and restredistribution Tl-201(RR-201 TI)SPECT imaging in evaluating myocardial viability among patients with STelevation acute myocardial infarction(AMI).Methods Twenty-six AMI patients underwent echocardiography and RR-201 Tl-SPECT imaging a week(baseline)after percutaneous coronary intervention(PCI)therapy.At baseline,wall motion score(WMS)and systolic strain were assessed,SPECT scoring were performed on 16 segments of left ventricle(LV).WMS was repeated more than 3 months later to assess myocardial viability,which is deemed as reference.Results ①Two hundred and sixty segments in the"at risk"regions were followed up for(5±2)months,among which 201 were identified as viable and 59 were not,according to the WMS.②In comparison to the reference standard,the sensitivity and specificity of RR-201 Tl-SPECT to predict myocardial viability were 87%(175/201)and 58%(34/59)respectively.③The sensitivity and specificity of systolic strain(Set)to predict myocardial viability after AMl were 81% and 66% respectively at the optimal cut-off value of-60%.④Set was moderately concordant with SPECT scoring(Kappa=0.40)and the agreement between the two methods was 77%(199/260).Conclusions In ST-elevation AMI,SI and RR-201 Tl-SPECT appears equivalent in predicting segmental recovery after reperfusion,and SI could be a convenient and low-cost alternative for the non-invasive evaluation of myocardial viability.
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Objective To detect the clinical value of evaluating myocardial viability in patients with old myocardial infaretion(OMI) by measuring myocardial isovolumie contraction motion indices with tissue Doppler imaging(TDI) under the quiescent condition. Methods The myocardial isovolumic contraction motion indices of 30 normal subjects and 30 patients with OMI were examined by TDI. The sample gate was located at left ventricular postero-septal,lateral,anterior,inferior,antero-septal and posterior walls in basal and middle segments separately. The peak positive and negative veiocities(VIVC1 ,VIVC2 ) during myocardial isovohimic contraction phase, and the difference(DIVC) between VIVC1 and VIVC2 were measured, which were analysed combined with the viable fraction(VF) calculated by single photon emission computed tomography (SPECT). Results VIVC1, DIVC were significantly decreased,and VIVC2 was significantly increased in infarct zones of patients with OMI than those of the normal subjects( P <0.05). Compared with normal subjects, myocardial isovolumic contraction motion indices of non-infarct wails in patients with OMI were steady( P >0.05). In OMI group,DIVC of short axis was significantly decreased than that in long axis( P <0.05). Statistic analysis showed that DIVC values on both of short and long axis had significant positive correlations with VF derived from SPECT,and the correlation coefficients were 0. 837 ( P<0. 001) and 0. 797( P<0. 001 ) ,respectively. The sensibility and specificity of evaluating viable myocardium was 75% and 75% separately supposing the cutoff of DIVC on short axis was more than - 1.50,and the sensibility and specificity was 77. 8% and 87.5% separately if the cutoff of DIVC on long axis was more than 0.92. Conclusions Myocardial isovolumic contraction's TDI of infarct zones in patients with OMI had characteristic changes. DIVC on both of short and long axis could be as a new method of evaluating myocardial viability.
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PURPOSE: To investigate the feasibility of Tl-201 SPECT with intracoronary injection (IC-I) in the detection of viable myocardium, we have performed SPECT imaging after direct intracoronary injection of Tl-201 and images were compared with those of stress-reinjection (Re-I) SPECT. METHODS: Fourteen coronary artery disease patients (male 11, mean age 54 years) who had myocardial infarction or demonstrated left ventricular wall motion abnormality on echocardiography were enrolled. Three mCi of Tl-201 was injected into both coronary arteries during angiography and images were acquired between 6- and 24-hour after injection. Reinjection imaging with 1 mCi of Tl-201 was performed at 4-hour after adenosine stress imaging with 3 mCi of Tl-201. Images were interpreted according to 4-grade visual scoring system (grade 0-3). Segments with mild to moderated uptake (< or=grade 1), and upgraded more than one score with reinjection, and were defined as viable myocardium. RESULTS: Image quality was poor in two cases with IC-I. Numbers of non-viable segments were 60 (23.8%) with IC-I, and 38 (15.1%) with Re-I, respectively. Overall agreement for perfusion grade per myocardial segment in each IC-I and Re-I was 76.5%. Overall agreement for viable segment between IC-I and Re-I was 90.5%. Only one out of 38 segments interpreted as non-viable with Re-I were interpretated as viable with IC-I. And 23 out of 214 segments interpreted as viable with Re-I were interpreted as non-viable with IC-I. CONCLUSION: Intracoronary Tl-201 SPECT seemed to be not advantageous over stress-rest reinjection imaging in the assessment of myocardial viability, mainly due to low count statistics at 6-hour or 24-hour delayed time points. The feasibility of intracoronary Tl-201 SPECT is considered to be limited.
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Humains , Adénosine , Angiographie , Maladie des artères coronaires , Vaisseaux coronaires , Échocardiographie , Infarctus du myocarde , Myocarde , Perfusion , Tomographie par émission monophotoniqueRésumé
PURPOSE: To investigate the feasibility of Tl-201 SPECT with intracoronary injection (IC-I) in the detection of viable myocardium, we have performed SPECT imaging after direct intracoronary injection of Tl-201 and images were compared with those of stress-reinjection (Re-I) SPECT. METHODS: Fourteen coronary artery disease patients (male 11, mean age 54 years) who had myocardial infarction or demonstrated left ventricular wall motion abnormality on echocardiography were enrolled. Three mCi of Tl-201 was injected into both coronary arteries during angiography and images were acquired between 6- and 24-hour after injection. Reinjection imaging with 1 mCi of Tl-201 was performed at 4-hour after adenosine stress imaging with 3 mCi of Tl-201. Images were interpreted according to 4-grade visual scoring system (grade 0-3). Segments with mild to moderated uptake (< or=grade 1), and upgraded more than one score with reinjection, and were defined as viable myocardium. RESULTS: Image quality was poor in two cases with IC-I. Numbers of non-viable segments were 60 (23.8%) with IC-I, and 38 (15.1%) with Re-I, respectively. Overall agreement for perfusion grade per myocardial segment in each IC-I and Re-I was 76.5%. Overall agreement for viable segment between IC-I and Re-I was 90.5%. Only one out of 38 segments interpreted as non-viable with Re-I were interpretated as viable with IC-I. And 23 out of 214 segments interpreted as viable with Re-I were interpreted as non-viable with IC-I. CONCLUSION: Intracoronary Tl-201 SPECT seemed to be not advantageous over stress-rest reinjection imaging in the assessment of myocardial viability, mainly due to low count statistics at 6-hour or 24-hour delayed time points. The feasibility of intracoronary Tl-201 SPECT is considered to be limited.
Sujets)
Humains , Adénosine , Angiographie , Maladie des artères coronaires , Vaisseaux coronaires , Échocardiographie , Infarctus du myocarde , Myocarde , Perfusion , Tomographie par émission monophotoniqueRésumé
The imaging technique that can provide detailed information on the left ventricular function, myocardial perfusion and viability at the same time will not only be helpful for the prognostic assessment of patients with ischemic heart disease but also be valuable in choosing appropriate therapeutic strategies. In recent years, multidetector CT (MDCT) has been proposed as a useful non-invasive imaging method of evaluating both coronary artery stenoses and cardiac morphology at the same time. MDCT has proved to be in excellent agreement with echocardiography and magnetic resonance imaging in the assessment of the left ventricular function. In addition, MDCT can provide information on myocardial viability, which can be assessed from the left ventricular wall thickness, myocardial perfusion, and a delayed contrast enhancement pattern. Despite several shortcomings to be the first-line modality for the assessment of ischemic heart disease, MDCT can provide valuable additional dynamic information in patients undergoing MDCT coronary angiography.