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1.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 36(4): 247-253, jul.-ago. 2017. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-163742

RESUMO

The prevalence and severity of obesity have increased over recent decades, reaching worldwide epidemics. Obesity is associated to coronary artery disease and other risk factors, including hypertension, heart failure and atrial fibrillation, which are all increased in the setting of obesity. Several noninvasive cardiac imaging modalities, such as echocardiography, cardiac computed tomography, magnetic resonance and cardiac gated single-photon emission computed tomography, are available in assessing coronary artery disease and myocardial dysfunction. Yet, in patients with excess adiposity the diagnostic accuracy of these techniques may be limited due to some issues. In this review, we analyze challenges and possibilities to find the optimal cardiac imaging approach to obese population (AU)


La prevalencia y la severidad de la obesidad se han incrementado en las últimas décadas, alcanzando el grado de epidemia a nivel mundial. La obesidad se asocia a enfermedades arteriales coronarias y otros factores de riesgo, incluyendo hipertensión, insuficiencia cardiaca y fibrilación auricular, que se incrementan en los casos de obesidad. Se dispone de diversas técnicas de imagen cardiaca no invasivas, tales como ecocardiografía, tomografía computarizada cardiaca, resonancia magnética y tomografía computarizada de emisión de fotón único cardiaca, para evaluar las enfermedades arteriales coronarias y la disfunción miocárdica. Sin embargo, en pacientes con exceso de adiposidad, la precisión diagnóstica de estas técnicas puede verse limitada debido a diversas cuestiones. En esta revisión analizamos las dificultades y las posibilidades de encontrar la técnica de imagen óptima en la población obesa (AU)


Assuntos
Humanos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca , Obesidade/complicações , Adiposidade/fisiologia , Doença das Coronárias , Fibrilação Atrial , Medicina Nuclear/métodos , Imageamento por Ressonância Magnética , Hipertensão/complicações , Ecocardiografia/métodos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares
2.
Rev Esp Med Nucl Imagen Mol ; 36(4): 247-253, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28262493

RESUMO

The prevalence and severity of obesity have increased over recent decades, reaching worldwide epidemics. Obesity is associated to coronary artery disease and other risk factors, including hypertension, heart failure and atrial fibrillation, which are all increased in the setting of obesity. Several noninvasive cardiac imaging modalities, such as echocardiography, cardiac computed tomography, magnetic resonance and cardiac gated single-photon emission computed tomography, are available in assessing coronary artery disease and myocardial dysfunction. Yet, in patients with excess adiposity the diagnostic accuracy of these techniques may be limited due to some issues. In this review, we analyze challenges and possibilities to find the optimal cardiac imaging approach to obese population.


Assuntos
Técnicas de Imagem Cardíaca , Doenças Cardiovasculares/diagnóstico por imagem , Obesidade/fisiopatologia , Adiposidade , Artefatos , Técnicas de Imagem Cardíaca/instrumentação , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Comorbidade , Vasos Coronários/diagnóstico por imagem , Tolerância ao Exercício , Reações Falso-Negativas , Reações Falso-Positivas , Coração/diagnóstico por imagem , Humanos , Obesidade/complicações , Obesidade/epidemiologia , Prevalência , Compostos Radiofarmacêuticos/farmacocinética , Fatores de Risco , Distribuição Tecidual
3.
J Nucl Cardiol ; 24(4): 1292-1301, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27052809

RESUMO

BACKGROUND: There are limited data on the impact of the imaging protocol (single-day stress-rest, SD, vs. dual-day, DD) on the change in left ventricular (LV) ejection fraction (EF) (post-stress-rest) in relation to ischemia and on outcome. METHODS: Using propensity score matching procedure, 490 of 1121 patients with known CAD, undergoing a SD or a DD in a multicenter study, were evaluated. Stress and rest gated-SPECT myocardial perfusion imaging was used to quantify LV perfusion, EF, and volumes. Outcome was assessed at an average follow-up time of 3.2 years. RESULTS: Post-stress LVEF in SD and DD were comparable across all degrees of ischemia. The change in LVEF in patients with severe ischemia was, however, higher in the DD protocol, independent of the extent of CAD. At follow-up, 240 patients (49.0%) required coronary revascularization (CR) and 52 patients (10.6%) had hard events. The ischemic burden was independently associated with CR and hard-events; the post-stress LVEF was associated with CR but the change in EF was not predictive of either CR or hard events. CONCLUSIONS: In patients with severe ischemia, underestimation of post-stress myocardial stunning could be observed with the SD protocol. Post-stress LVEF and the extent ischemia, but not the change in EF, are predictive of CR and hard events.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Protocolos Clínicos , Imagem de Perfusão do Miocárdio/métodos , Volume Sistólico , Função Ventricular Esquerda , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Nutr Metab Cardiovasc Dis ; 24(6): 588-93, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24472632

RESUMO

BACKGROUND AND AIMS: Despite an extensive use of stress myocardial perfusion single-photon emission computed tomography (MPS), no study addressed the role of perfusion imaging in diabetic patients with abnormal resting electrocardiogram (ECG). We compared analytical approaches to assess the added value of stress MPS variables in estimating coronary heart disease outcomes in diabetic patients with abnormal resting ECG. METHODS AND RESULTS: A total of 416 patients with diabetes and abnormal resting ECG who underwent stress MPS were prospectively followed up after the index study. The end point was the occurrence of a major cardiac event, including cardiac death and nonfatal myocardial infarction. At the end of follow-up (median 58 months), 42 patients experienced events. MPS data increased the predictive value of a model including traditional cardiovascular risk factors and left ventricular (LV) ejection fraction (likelihood ratio χ² from 17.54 to 24.15, p < 0.05, with a C statistic of 0.72, 95% confidence interval: 0.65-0.79). The addition of MPS data resulted in reclassification of 25% of the sample with a net reclassification improvement of 0.20 (95% confidence interval: 0.05-0.36). Overall, 63 patients were reclassified to a lower risk category, with a 5-year event rate of 3.5%, and 40 patients were reclassified to a higher risk category, with a 5-year event rate of 20%. CONCLUSION: The addition of MPS findings to a model based on traditional cardiovascular risk factors and LV ejection fraction improves risk classification for incident cardiac events in diabetic patients with abnormal resting ECG.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/diagnóstico por imagem , Cardiomiopatias Diabéticas/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Idoso , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Estudos de Coortes , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/fisiopatologia , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/fisiopatologia , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Compostos Radiofarmacêuticos , Fatores de Risco , Estresse Fisiológico , Volume Sistólico , Tecnécio Tc 99m Sestamibi , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/fisiopatologia
5.
Q J Nucl Med Mol Imaging ; 54(2): 129-44, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20588210

RESUMO

Cardiac imaging with gated single-photon emission computed tomography (SPECT) allows the evaluation of myocardial perfusion and analysis of global and regional left ventricular function. Gated SPECT is a validated and established diagnostic and prognostic method for evaluation of patients with suspected and known coronary artery disease. Significant improvements in software and gamma camera technology in SPECT cardiac imaging have been obtained. New detectors open a scenario for faster imaging with lower radiation dose to the patient. Appropriate use of the SPECT imaging is regulated by evidence-based guidelines and appropriateness criteria as well as by third-party payers in an effort to restrain the unsustainable growth of imaging testing recently observed. Future of cardiac SPECT imaging will be driven by societal demand for cost effective, accurate, and safe testing, which will improve meaningfully patients' management and outcomes.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Tomografia por Emissão de Pósitrons , Prognóstico , Medição de Risco
6.
Minerva Endocrinol ; 34(3): 205-21, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19859044

RESUMO

Diabetes mellitus is a complex clinical entity that will grow in importance in the future. The complications of diabetes have a significant impact on patient survival and quality of life, particularly with respect to coronary artery disease (CAD). Appropriate screening and aggressive intervention can significantly benefit many patients with diabetes. In addition, it is important to consider strategies useful not only in the diagnosis of CAD but also in the prognostic evaluation of diabetic patients with coronary disease. Prognostic data are essential in defining risk categories and to apply appropriate treatment for the degree of risk. Therefore, accurate cardiovascular risk stratification of patients with type 2 diabetes is required. However, this can be a problematic issue because the clinical presentation and progression of CAD differs between diabetic and nondiabetic subjects. In addition to a higher prevalence of CAD, patients with diabetes experience more diffuse and extensive coronary artery involvement, more often have left ventricular dysfunction, a more advanced coronary disease at the time of diagnosis, and more often experience silent ischemia. Furthermore, diabetic patients have frequently a less favorable response to revascularization procedures and a poorer long-term outcome. The purpose of this review is to discuss the relative role of various procedures for diagnosis of CAD and for cardiac risk stratification in patients with diabetes.


Assuntos
Doenças Cardiovasculares/epidemiologia , Angiopatias Diabéticas/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/diagnóstico por imagem , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Prognóstico , Cintilografia , Medição de Risco
7.
Eur J Clin Invest ; 39(8): 664-70, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19490065

RESUMO

BACKGROUND: Reduced systolic reserve on effort may be present in subjects with hypertension but no evidence of hypertensive cardiomyopathy. We assessed the determinants of abnormal cardiac performance during exercise in hypertensive patients without left ventricular hypertrophy. MATERIALS AND METHODS: Thirty-five newly diagnosed, never-treated-earlier hypertensive patients without definite indication for left ventricular hypertrophy at echocardiography underwent radionuclide ambulatory monitoring of left ventricular function at rest and during upright bicycle exercise testing. RESULTS: The patients were classified into two groups according to their ejection fraction response to exercise. In 21 patients (group 1), the ejection fraction increased > or = 5% with exercise and in 14 patients (group 2), the ejection fraction either increased < 5% or decreased with exercise. Patients of group 1 had lower peak filling rate at rest and less augmentation in end-diastolic volume during exercise (both P < 0.01) when compared with patients of group 2. A significant relationship between the magnitude of change in ejection fraction with exercise and both peak filling rate at rest (r = 0.58, P < 0.01) and exercise-induced change in end-diastolic volume (r = 0.45, P < 0.01) was found. CONCLUSIONS: In newly diagnosed, never-treated-earlier hypertensive subjects with no evidence of hypertensive cardiomyopathy, the cardiac response to exercise is dependent on adequate diastolic filling volume to maintain systolic performance.


Assuntos
Diástole/fisiologia , Coração/fisiopatologia , Hipertensão/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Angiografia , Teste de Esforço , Tolerância ao Exercício , Feminino , Coração/diagnóstico por imagem , Humanos , Hipertensão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cintilografia
8.
Eur J Clin Invest ; 38(12): 910-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19021715

RESUMO

BACKGROUND: Fatigability and dyspnoea on effort are present in many patients with Fabry's disease. We assessed the determinants of cardiac performance during exercise in patients with Fabry's disease and preserved left ventricular ejection fraction at rest. MATERIALS AND METHODS: Sixteen patients with Fabry's disease and 16 control subjects underwent radionuclide angiography at rest and during exercise, tissue Doppler echocardiography and magnetic resonance imaging at rest. RESULTS: The exercise-induced change in stroke volume was +25 +/- 14% in controls and +5.8 +/- 19% in patients with Fabry's disease (P < 0.001). In 10 patients (group 1), the stroke volume increased (+19 +/- 10%), and in 6 patients (group 2) it decreased (-16 +/- 9%) with exercise. Patients of group 2 were older, had worse renal function, higher left ventricular mass and impaired diastolic function compared to group 1. The abnormal stroke volume response to exercise in group 2 was associated with a decrease in end-diastolic volume (P < 0.001) and a lack of reduction of end-systolic volume (P < 0.01) compared with both controls and group 1. The ratio of peak early-diastolic velocity from mitral filling to peak early-diastolic mitral annulus velocity was the only independent predictor of exercise-induced change in stroke volume (B -0.44; SE 0.119; beta-0.70; P < 0.005). CONCLUSIONS: The majority of patients with Fabry's disease were able to augment stroke volume during exercise by increasing end-diastolic volume, whereas patients with more advanced cardiac involvement may experience the inability to increase cardiac output by the Frank Starling mechanism.


Assuntos
Baixo Débito Cardíaco/fisiopatologia , Teste de Esforço , Tolerância ao Exercício/fisiologia , Doença de Fabry/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doença de Fabry/genética , Feminino , Coração , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Eur J Nucl Med Mol Imaging ; 35(4): 851-85, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18224320

RESUMO

Radionuclide imaging of cardiac function represents a number of well-validated techniques for accurate determination of right (RV) and left ventricular (LV) ejection fraction (EF) and LV volumes. These first European guidelines give recommendations for how and when to use first-pass and equilibrium radionuclide ventriculography, gated myocardial perfusion scintigraphy, gated PET, and studies with non-imaging devices for the evaluation of cardiac function. The items covered are presented in 11 sections: clinical indications, radiopharmaceuticals and dosimetry, study acquisition, RV EF, LV EF, LV volumes, LV regional function, LV diastolic function, reports and image display and reference values from the literature of RVEF, LVEF and LV volumes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "prevailing or general consensus". The guidelines are designed to assist in the practice of referral to, performance, interpretation and reporting of nuclear cardiology studies for the evaluation of cardiac performance.


Assuntos
Testes de Função Cardíaca , Coração/diagnóstico por imagem , Radioisótopos , Europa (Continente) , Coração/fisiologia , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Medicina Nuclear/normas , Cintilografia , Função Ventricular Esquerda
10.
Q J Nucl Med Mol Imaging ; 49(1): 4-18, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15724132

RESUMO

Myocardial perfusion imaging (MPI) is important for the management of patients with suspected or known coronary artery disease (CAD). Nuclear cardiology is the most widely used noninvasive approach for the assessment of myocardial perfusion. The available single-photon emission computed tomography (SPECT) flow agents are characterized by a rapid myocardial extraction and by a cardiac uptake proportional to blood flow. In addition, different positron emission tomography (PET) tracers may be used for the quantitative measurement of myocardial blood flow and coronary flow reserve. The decrease in blood flow, determined by coronary artery stenosis, produces myocardial ischemia leading to perfusion abnormalities detectable by SPECT or PET in the early phase of ischemia. Other imaging techniques, such as contrast echocardiography and magnetic resonance imaging (MRI) have been more recently proposed as alternative methods for the evaluation of myocardial perfusion. Although several technical aspects have to be better defined to use contrast echocardiography in clinical practice, this approach appears promising for the evaluation of myocardial perfusion. MRI has also been proposed for the assessment of myocardial perfusion by measuring the alteration of regional myocardial magnetic properties after the intravenous injection of contrast agents. Due to the high contrast and spatial resolution of the technique, MRI allows differentiating sub-endocardial and sub-epicardial perfusion, emerging as a potential alternative non-ionizing technique to evaluate myocardial perfusion. This review illustrates the noninvasive imaging modalities for the evaluation of myocardial perfusion, underlying advantages and disadvantages of each technique.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Ecocardiografia/métodos , Imageamento por Ressonância Magnética/métodos , Cintilografia/métodos , Disfunção Ventricular Esquerda/diagnóstico , Doença da Artéria Coronariana/complicações , Vasos Coronários/patologia , Ecocardiografia/tendências , Humanos , Imageamento por Ressonância Magnética/tendências , Cintilografia/tendências , Disfunção Ventricular Esquerda/etiologia
11.
Q J Nucl Med ; 46(4): 323-30, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12411873

RESUMO

The aim of evidence-based medicine is to integrate individual clinical expertise with the best available external clinical evidence from systematic research. The aim of this article is to introduce the concept of evidence based medicine and to review the evidence for applying cardiovascular nuclear medicine in various clinical settings. A systematic review is defined as a scientific technique to identify and summarize evidence on effectiveness of interventions and to allow the consistency of research. Different clinical applications of nuclear medicine procedures in cardiology have been reviewed. Radionuclide imaging techniques appear to be appropriate in risk assessment, prognosis and evaluation of therapy in patients after acute myocardial infarction. In patients with unstable angina, radionuclide testing is indicated in the identification of ischemia within the distribution of the "culprit" lesion or in remote areas. Exercise and pharmacological cardiac perfusion imaging are appropriate and useful in the diagnosis and prognosis of chronic coronary artery disease. Nuclear medicine procedures are also useful in the assessment of myocardial viability in patients with left ventricular dysfunction, in the assessment of interventions for the evaluation of patients after percutaneous transluminal coronary angioplasty and coronary artery bypass grafting. There has been rapid evolution in radionuclide imaging technologies and both the number and the complexity of choices for the clinician have increased. Further progress in technology and clinical applications of nuclear cardiology may be expected. The development of new instrumentation and of new agents will allow consistent progress and improve the state-of-art of nuclear cardiology. Thus, guidelines for the use of cardiac radionuclide imaging have been difficult to develop and apply. An evidence-based approach may be useful for the best use of nuclear medicine procedures in cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Coração/diagnóstico por imagem , Medicina Nuclear/métodos , Doença Aguda , Angina Instável/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Doença Crônica , Medicina Baseada em Evidências , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico por imagem , Cintilografia
12.
Tumori ; 88(3): S43-5, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12365387

RESUMO

AIMS AND BACKGROUND: Sentinel lymph node (SLN) detection is currently employed in patients with malignant melanoma (MM) to spare them unnecessary lymph node dissection. METHODS AND STUDY DESIGN: We investigated 241 patients (130 men and 111 women, median age, 50 years (range, 14-92) with MM (192 before and 51 after surgical biopsy); two of them had more than one melanoma lesion. In each patient approx. 10 MBq of 99mTc Nanocoll in 0.1 mL (Nycomed Amersham Sorin; particle size range, 3-80 nm) was injected intradermally around the MM lesion or surgical scar. Dynamic acquisition was performed for 20 minutes (20 frames/min) and the study was concluded within four hours of injection. Using an external radioactive marker, the skin over the SLN was marked with China ink. RESULTS: 294 SLNs were scintigraphically identified: 117 in the inguinal region, 147 in the axillae, four in the submandibular region, three in the laterocervical region and 23 at other sites. In two patients no drainage was detected. In 43 patients more than one sentinel node was identified. In 13 patients with lesions located in the trunk the tracer drained towards multiple lymph node stations or unexpected lymph nodes (nine cases). Histology and immunohistochemistry diagnosed MM in 25 SLNs; 19 were positive for metastasis with hematoxylin-eosin staining, five with Hmb45 and one with CD68 immunostaining. All 25 detected lymphatic basins were excised. In nine of these basins there was metastatic involvement of at least one other lymph node besides the SLN. During follow-up which ranged from six to 86 months, metastatic disease was found in only one patient with a histologically negative SLN six months after surgery. CONCLUSIONS: This study confirms the utility of scintigraphic SLN detection in patients with MM. In most of the cases the procedure led the surgeon to evaluate the drainage area, which is unpredictable for lesions in the trunk and may be difficult to delineate using only patent blue dye. Furthermore, in approximately 10% of cases we observed dual drainage from individual lesions, mainly those located on the trunk. We will proceed to compare the results obtained during follow-up with those of an investigational group of patients with melanoma who were not subjected to lymphoscintigraphy for SLN detection in order to obtain well-founded information on the prognostic value of this technique.


Assuntos
Linfonodos/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cintilografia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/patologia
13.
Tumori ; 88(4): 352-3, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12400991

RESUMO

AIMS AND BACKGROUND: The aim of our study was to assess the feasibility of sentinel lymph node (SLN) detection in colon cancer using a radiochromoguided technique. The regional lymph node status is crucial for colorectal cancer staging and the stage of disease at the time of diagnosis is the main factor influencing therapeutic decision-making and patient survival. METHODS AND STUDY DESIGN: Between April and June 2001 eight patients with colon cancer were studied by radiochromoguided sentinel lymph node mapping. At the time of surgery 2 ml of patent blue dye was injected around the tumor, followed after 10 minutes by 2 ml of 99mTc-labeled albumin. After 30 minutes the SLN was identified by a gamma probe. Surgery was completed by standard resection. The SLN was processed for permanent hematoxylin and eosin staining and for immunohistochemical examination with anti-CEA and anti-cytokeratin antibodies. RESULTS: SLNs were identified in six patients; two were negative for metastasis by hematoxylin-eosin and immunohistochemical examination, two were positive for metastasis by both methods, and two were negative for metastasis by hematoxylin-eosin but positive by immunohistochemical examination. There were no false negative SLNs and no complications occurred. CONCLUSION: The actual utility of SLN detection for prognostic purposes is still unknown, but intraoperative radiochromoguided SLN mapping is technically feasible in colon cancer, although it is associated with more technical difficulties than in breast cancer and malignant melanoma.


Assuntos
Neoplasias do Colo/cirurgia , Biópsia de Linfonodo Sentinela , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregado de Albumina Marcado com Tecnécio Tc 99m
14.
Eur J Nucl Med ; 28(11): 1616-23, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702102

RESUMO

It is known that contractile reserve may be blunted if perfusion and coronary flow reserve are reduced. Thus, it is conceivable that the predictive accuracy of dobutamine echocardiography may differ according to perfusion tracer uptake. The aim of this study was therefore to assess the relationship between the level of thallium-201 uptake and the accuracy of dobutamine echocardiography in identifying reversible dysfunction. Sixty-nine patients (age 59+/-8 years, ejection fraction 40%+/-11%) with chronic coronary artery disease scheduled for coronary revascularisation were studied. All patients underwent rest 201Tl single-photon emission tomography and two-dimensional echocardiography at rest and during low-dose dobutamine infusion on the same day before revascularisation and repeated echocardiography at least 30 days thereafter. At follow-up, recovery of function was observed in 49% of 339 dysfunctional segments. The percentage of segments with post-revascularisation recovery of function and the percentage with contractile reserve increased in parallel with 201Tl uptake both in the total group of segments (chi2=35.5, P<0.0001 and chi2=35.9, P<0.0001, respectively) and among the 183 akinetic segments (chi2=44.4, P<0.0001 and chi2=14.6, P<0.05, respectively). The dysfunctional segments were divided into three groups according to 201Tl uptake: (a) uptake <65%, (b) uptake between 65% and 79%, (c) uptake >80%. The positive predictive value increased significantly with the level of 201Tl uptake, and was suboptimal (46%) in akinetic segments with severely reduced 201Tl uptake. The negative predictive value decreased significantly with 201Tl uptake, and it was less than suboptimal (29%) in akinetic segments with normal tracer uptake. Sensitivity was lower in the subset of akinetic segments (42%-63%) than in all dyssynergic segments (63%-76%), whereas specificity was very high in akinetic segments (80%-84%). It is concluded that the accuracy of low-dose dobutamine echocardiography in predicting reversibility of regional dysfunction varies considerably according to 201Tl uptake at rest and to the severity of regional dysfunction.


Assuntos
Doença das Coronárias/terapia , Dobutamina , Ecocardiografia sob Estresse , Revascularização Miocárdica , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Sensibilidade e Especificidade
18.
J Nucl Cardiol ; 7(5): 406-13, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11083188

RESUMO

BACKGROUND: Technetium 99m sestamibi cardiac scintigraphy is widely used as a means of predicting myocardial viability in patients with chronic ischemic left ventricular (LV) dysfunction. No data are available comparing the results of visual and quantitative analysis of tomographic imaging in the assessment of myocardial viability. The aim of this study was to directly compare visual and quantitative analysis of resting sestamibi single photon emission computed tomography in the identification of viable myocardium in patients with chronic LV dysfunction. METHODS AND RESULTS: Sixty-five patients with an earlier myocardial infarction and LV dysfunction that had occurred within 1 week underwent echocardiography and resting sestamibi SPECT. In each patient, regional tracer distribution was visually assessed and quantitatively measured in 13 segments. Regional LV function was evaluated in corresponding segments by means of echocardiography. All patients underwent revascularization, and echocardiography was repeated 12 months later as a means of assessing the recovery of regional LV function. Among all akinetic or dyskinetic revascularized segments, 66 of 112 viable segments (59%) and 85 of 100 nonviable segments (81%) were identified by means of visual analysis. Eighty-two of 112 viable segments (73%; P<.05 vs. visual analysis) and 74 of 100 nonviable segments (74%; P = .3 vs. visual analysis) were identified by means of quantitative analysis, with a threshold of 55%. Receiver operating characteristic curve areas constructed by using visual and quantitative analyses for the detection of myocardial viability in all 212 akinetic or dyskinetic segments were 0.79+/-0.04 and 0.81+/-0.03, respectively (P = not significant). Overall concordance in the detection of myocardial viability between visual and quantitative analysis was observed in 165 of akinetic or dyskinetic dysfunctional segments (78%), with a kappa value of 0.6. CONCLUSIONS: The results of this study demonstrate that, in patients with chronic myocardial infarction and LV dysfunction, visual and quantitative analysis of sestamibi tomographic images at rest have similar overall accuracy in predicting the recovery of LV function after coronary revascularization procedures.


Assuntos
Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem , Doença Crônica , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Variações Dependentes do Observador , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda
19.
Radiol Med ; 99(4): 258-63, 2000 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-10884826

RESUMO

PURPOSE: To investigate the role of technetium-99m (99mTc) tetrofosmin single-photon emission Computed Tomography (SPECT) associated with nitrate administration in the detection of hypoperfused but still viable myocardium in patients with chronic coronary artery disease and left ventricular (LV) dysfunction. MATERIAL AND METHODS: Twenty-two patients (mean age 54 +/- 11 years) with coronary artery disease, previous myocardial infarction and LV dysfunction (LV ejection fraction 38 +/- 13%) were examined. On different days all patients underwent 99mTc tetrofosmin (740 MBq) SPECT under control conditions at rest and after sublingual nitroglycerin administration (10 mg). Regional tetrofosmin activity was quantitatively measured in 22 myocardial segments per patient. In each segment, tracer uptake was expressed as a percentage of the region with the peak activity. RESULTS: Under control conditions, 267 myocardial segments (55%) showed normal tetrofosmin uptake (> 70% of peak activity), 107 segments (22%) showed a moderate reduction (51-70%) and 110 segments (23%) a severe reduction (< or = 50%) in tracer uptake. Among the 110 segments with a severe reduction in tetrofosmin uptake, 20 (18%) showed increased tracer uptake > or = 10% of after nitrate administration (from 44 +/- 5% to 58 +/- 3%, p < 0.0001). The remaining 90 (82%) segments with a severe reduction in tetrofosmin uptake did not show any change after nitroglycerin administration (from 38 +/- 9% to 39 +/- 8%, p = ns). CONCLUSIONS: In patients with chronic coronary artery disease and LV dysfunction, tetrofosmin cardiac SPECT associated with sublingual nitrate administration allows the detection of severely hypoperfused but still viable myocardium.


Assuntos
Coração/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico por imagem , Nitroglicerina , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Vasodilatadores , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Doença Crônica , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Disfunção Ventricular Esquerda/fisiopatologia
20.
J Nucl Cardiol ; 7(3): 235-41, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10888394

RESUMO

BACKGROUND: This study was designed to compare the results of rest-redistribution thallium-201 imaging with those of rest technetium 99m furifosmin single photon emission computed tomography in the same patients with chronic ischemic left ventricular (LV) dysfunction. METHODS: Twenty-one patients (mean age 62 +/- 9 years) with chronic myocardial infarction and LV dysfunction (mean LV ejection fraction 34% +/- 8%) underwent rest-redistribution thallium imaging and resting furifosmin single photon emission computed tomography on the same day. In each patient, regional thallium and furifosmin activity was quantitatively measured in 13 myocardial segments. Regional LV function was assessed in corresponding segments by echocardiography. RESULTS: At thallium imaging, 91 (33%) segments had normal uptake, 16 (6%) showed reversible defects, and the remaining 166 (61%) irreversible defects. Of these 166 irreversible defects, 74 (45%) had moderate (> or =58% of peak activity) and 92 (55%) severe (<58% of peak activity) reduction of thallium uptake. Regional furifosmin uptake was significantly related to both rest (r = 0.87, P < .0001) and redistribution (r = 0.90, P < .0001) thallium activity. Agreement in the evaluation of regional perfusion status between thallium and furifosmin imaging was observed in 70% of the 84 hypokinetic segments (kappa = 0.54) and in 76% of the 78 akinetic or dyskinetic segments (kappa = 0.60). Concordance in the detection of myocardial viability between thallium and furifosmin imaging was observed in 69 (82%) of hypokinetic regions (kappa = 0.60) and in 65 (83%) of akinetic or dyskinetic regions (kappa = 0.67). CONCLUSIONS: These results suggest that in patients with chronic coronary artery disease and LV dysfunction, quantitative rest-redistribution thallium scintigraphy and furifosmin tomography at rest provide similar results in the evaluation of perfusion status and in the detection of myocardial viability.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Tecnécio , Radioisótopos de Tálio , Função Ventricular Esquerda , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
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