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2.
Nuklearmedizin ; 50(1): 9-14, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21165540

RESUMO

AIM: We compared and delineated possible differences of model-based analysis of ECG-gated SPECT using (99m)Tc-sestamibi (Tc-SPECT) with ECG-gated ¹8F-fluorodeoxyglucose-PET (FDG-PET) for determination of end-diastolic (EDV) and end-systolic (ESV) cardiac volumes, left ventricular ejection fraction (LVEF), and myocardial mass (LVMM). PATIENTS, METHODS: 24 patients (21 men; age: 54±12years) with coronary artery disease underwent Tc-SPECT and FDG-PET imaging for evaluation of myocardial perfusion and viability. By using model-based analysis EDV, ESV, LVEF and LVMM were calculated from short axis images of both Tc-SPECT and FDG-PET. RESULTS: Left ventricular volumes by Tc-SPECT and FDG-PET were 176±60 ml and 181±59 ml for EDV, and 97±44 ml and 103±45 ml for ESV respectively, LVEF was 47±8% by Tc-SPECT and 45±9% by FDG-PET. The LVMM was 214±40 g (Tc-SPECT) and 202±43 g (FDG-PET) (all p = NS, paired t-test). A significant correlation was observed between Tc-SPECT and FDG-PET imaging for calculation of EDV (r = 0.93), ESV (r = 0.93), LVEF (r = 0.83) and LVMM (r = 0.72). CONCLUSION: ECG-gated Tc-SPECT and FDG-PET using two tracers with different characteristics (perfusion versus metabolism) showed close agreement concerning measurements of left ventricular volumes, contractile function and myocardial mass by using a model-based analysis.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Fluordesoxiglucose F18 , Volume Sistólico , Tecnécio , Disfunção Ventricular Esquerda/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tecnécio/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Disfunção Ventricular Esquerda/metabolismo
3.
Nuklearmedizin ; 45(4): 171-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16964343

RESUMO

AIM: We investigated the impact of photon attenuation in myocardial perfusion imaging with SPECT and PET in patients with coronary artery disease. In fact, the regional tracer distribution can be quantitatively assessed by polar map analysis if the effects of photon attenuation are accounted for. PET imaging permits accurate measurement of and correction for photon attenuation, whereas results of attenuation correction in SPECT imaging have been inconsistent. PATIENTS, METHODS: We compared photon attenuation in resting perfusion imaging studies with SPECT ((99m)Tc-sestamibi) and PET ((13)N-ammonia) from 21 patients. Transaxial images were reconstructed with and without attenuation correction and reoriented into short axis images. Polar map analysis was utilized to generate regional tracer uptake in six anatomical segments. RESULTS: Average segmental photon attenuation calculated as the ratio of counts in corrected and uncorrected images was 7.2 +/- 1.4 in SPECT and 14.0 +/- 3.1 in PET imaging (p < 0.01). This attenuation factor was significantly related to body mass index for both methods (p < 0.001). While attenuation correction for SPECT imaging did compensate for attenuation effects in the inferior wall (from -15% to +6% vs. PET), relative tracer uptake in the anterior wall in SPECT images was significantly reduced after attenuation correction (from -2% to -18% vs. PET, p < 0.01). CONCLUSION: Differential effects of attenuation correction for myocardial SPECT perfusion imaging need to be considered when algorithms designed to compensate effects of photon attenuation in SPECT imaging are employed in clinical practice.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Tecnécio Tc 99m Sestamibi
4.
Eur J Nucl Med Mol Imaging ; 33(12): 1508-12, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16909224

RESUMO

PURPOSE: Nuclear cardiology is a well-validated, non-invasive imaging modality that is highly cost-effective as a diagnostic and prognostic tool in the evaluation of patients with known or suspected coronary artery disease. However, the number of procedures in Europe is very far from that which would be expected on the basis of epidemiological data, particularly when comparison is made with the USA. As a preliminary step for future action aimed at improving and increasing nuclear cardiology practice in Europe, the European Council of Nuclear Cardiology performed a survey to identify the regulatory issues and the training components pertaining to the practice of nuclear cardiology. METHODS: a questionnaire was sent to 31 national nuclear medicine societies and to 40 national cardiology societies. The main areas covered by the survey were: (1) the license requirements, (2) the theoretical and practical aspects of training and (3) supervision of the stress test during a nuclear cardiology study. RESULTS: The results show that, in a setting of wide heterogeneity of national regulations, education and professional practice, nuclear medicine is a restricted and closely regulated specialty. This situation guarantees the quality and safe use of radionuclides; at the same time, however, it limits integration of nuclear medicine into the clinical arena. CONCLUSION: Cardiologists should become more involved in nuclear cardiology, to further stimulate the use of this powerful diagnostic and prognostic imaging modality.


Assuntos
Cardiologia/legislação & jurisprudência , Coleta de Dados , Medicina Nuclear/legislação & jurisprudência , Sociedades Médicas , Cardiologia/educação , Europa (Continente) , Teste de Esforço , Licenciamento , Medicina Nuclear/educação , Inquéritos e Questionários
5.
Eur J Clin Invest ; 36(5): 326-32, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16634836

RESUMO

BACKGROUND: Approximately 10-30% of patients with typical chest pain present normal epicardial coronaries. In a proportion of these patients, angina is attributed to microvascular dysfunction. Previous studies investigating whether angina is the result of abnormal resting or stress perfusion are controversial but limited by varying inclusion criteria. Therefore, we investigated whether microvascular dysfunction in these patients is associated with perfusion abnormalities at rest or at stress. PATIENTS AND METHODS: In 58 patients (39 female, 19 male, mean age 58+/-10 years) with angina and normal angiogram as well as 10 control patients with atypical chest pain and normal coronaries (six female, four male, mean age 53+/-11 years) myocardial blood flow (MBF) was measured at rest and under dipyridamole using 13N-ammonia PET. Resting MBF and coronary flow reserve (CFR) as the ratio of hyperaemic to resting MBF were corrected for rate-pressure-product (RPP): normalized resting MBF (MBFn)=MBFx10,000/RPP and CFRn=CFRxRPP/10,000. RESULTS: Sixteen/58 patients had a normal CFRn (=2.5; group I; CFRn: 3.1+/-0.88); the same as the controls (CFRn: 3.3+/-0.74). Forty-two/58 patients presented a reduced CFRn (group II; CFRn: 1.78+/-0.57). Group II had both a higher MBFn (group II: 1.30+/-0.33 vs. Group I: 1.03+/-0.26; P<0.05 and vs. controls: 1.07+/-0.19; P<0.01) and a lower hyperaemic MBF (group II: 2.25+/-0.76 mL g-1 min-1 vs. Group I: 3.07+/-0.78 mL g-1 min-1; P<0.001 and vs. controls: 3.41+/-0.94 mL g-1 min-1; P<0.0001). CONCLUSION: Impaired CFRn in patients with typical angina and normal angiogram is owing to both an increased resting and reduced hyperaemic MBF. Therefore, PET represents a prerequisite for further studies to optimize treatment in individuals with anginal pain and normal coronary angiogram.


Assuntos
Circulação Coronária , Angina Microvascular/fisiopatologia , Adulto , Idoso , Angiografia Coronária , Teste de Esforço , Feminino , Humanos , Hiperemia/fisiopatologia , Processamento de Imagem Assistida por Computador/métodos , Masculino , Angina Microvascular/diagnóstico por imagem , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Resistência Vascular
6.
Drugs R D ; 5(3): 141-51, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15139775

RESUMO

OBJECTIVE AND DESIGN: ITF-1697 is a chemically modified LYS-Pro tetrapeptide that corresponds to sequence 113-116 of C-reactive protein. Previous studies have demonstrated significant anti-ischaemic and antithrombotic activity of this tetrapeptide. The aim of this prospective, randomised, double-blind study in patients with acute myocardial infarction undergoing coronary revascularisation was to investigate the safety and efficacy of prolonged intravenous (i.v.) infusion of ITF-1697 at different doses on reduction of infarct size, as assessed by radionuclide imaging. PATIENTS AND METHODS: Injection of technetium-99m (Tc99m) was followed by injection of ITF-1697 or placebo bolus and 24-hour infusion in patients with acute myocardial infarction. Percutaneous transluminal coronary angioplasty (PTCA) was performed and succeeded by radionuclide imaging. A second Tc99m injection and radionuclide imaging was performed 7 days after the PTCA or at hospital discharge. The primary efficacy variable was set as the ratio between the myocardial salvage (size of the initial perfusion defect minus the final size of the infarct) and the initial area at risk (myocardial salvage index). Twenty-three patients were included in the study protocol, of whom nine were randomised to the ITF-1967 dose 1 group (loading dose 55 microg/kg i.v., infusion 0.5 microg/kg/min for 24 hours), a further nine to the ITF-1697 dose 2 group (loading dose 110 microg/kg i.v., infusion 1.0 microg/kg/min for 24 hours), and the remaining five to the placebo group. RESULTS: The defined safety variables (adverse events, laboratory parameters, vital signs and clinical outcome) exhibited no relationship to the application of ITF-1697. Comparison of myocardial salvage index revealed no statistical difference within the three groups (p = 0.65). Hypothesis testing on the myocardial salvage as well as the empirical and bias-correct confidence intervals (CIs) revealed significant differences between the ITF-1697 dose 2 group and the placebo group (95% CI 2.75, 18.07). CONCLUSION: The application of the tetrapeptide ITF-1697 during acute myocardial infarction to reduce infarct size was found to be feasible and safe in this pilot trial.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Oligopeptídeos/efeitos adversos , Oligopeptídeos/uso terapêutico , Adulto , Angioplastia Coronária com Balão/métodos , Pressão Sanguínea , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Oligopeptídeos/administração & dosagem , Projetos Piloto , Estudos Prospectivos , Cintilografia
7.
Circulation ; 104(9): 1005-11, 2001 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-11524393

RESUMO

BACKGROUND: The aim of this prospective study was to investigate the concordance between quantitative resting (201)Tl uptake as an established myocardial viability index and the electrical activity of the heart, determined by NOGA nonfluoroscopic electroanatomic mapping. METHODS AND RESULTS: The myocardial resting and late resting thallium uptakes of 384 myocardial segments from 32 patients (27 males aged 65+/-8 years) with previous myocardial infarction and chronic stable angina were compared with unipolar voltage potentials and local shortening of the left ventricle as assessed by electroanatomic mapping. The quantitative thallium uptake data were analyzed by polar map analysis by division into 12 comparable myocardial segments, as represented in electroanatomic mapping images. Unipolar voltage potentials exhibited a significant logarithmic correlation with both resting and late resting thallium uptake (attenuation corrected: r=0.660 and r=0.744; non-attenuation corrected: r=0.623 and r=0.721). Receiver operator characteristic analyses revealed unipolar voltage cutoff points of 12.0 mV (predictive accuracy 0.853, P< 0.001; sensitivity/specificity 81%) for normal myocardium and 6.4 mV (predictive accuracy 0.901, P< 0.001; sensitivity/specificity 82%) for nonviable myocardium assessed by attenuation-corrected (201)Tl late resting images and of 12.7 mV (predictive accuracy 0.822, P<0.001; sensitivity/specificity 75%) and 6.5 mV (predictive accuracy 0.808, P<0.001; sensitivity/specificity 73%) for non-attenuation-corrected late resting (201)Tl images. CONCLUSIONS: These results indicate that the unipolar voltage potentials obtained by electroanatomic mapping correlate well with standard quantitative late resting (201)Tl imaging for the evaluation of myocardial viability; thus, NOGA endocardial mapping provides useful "online" data at the time of catheterization, especially when information from other methods for viability assessment is unavailable.


Assuntos
Cateterismo Cardíaco , Técnicas Eletrofisiológicas Cardíacas/métodos , Coração/diagnóstico por imagem , Adulto , Endocárdio/diagnóstico por imagem , Endocárdio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Radioisótopos de Tálio
8.
Coron Artery Dis ; 12(3): 167-72, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11352072

RESUMO

BACKGROUND: Recurrent ischemic events occur during the hospital stay of 7-32% of patients after successful thrombolytic treatment of acute myocardial infarction (AMI). OBJECTIVE: To define the association between postinfarction angina pectoris and the clinical, angiographic, and intravascular ultrasound (IVUS) parameters of the infarct-related artery for consecutive prospectively included patients. METHODS: Clinical, qualitative, and quantitative angiographic and IVUS data for 64 patients (56 men, aged 53+/-12 years) with thrombolysis of AMI were analyzed. All patients underwent coronary angiography and pre-interventional IVUS measurement electively within 1 month of AMI or at the time of the occurrence of postinfarction angina pectoris. Classification as adaptive or constrictive remodeling was according to whether the cross-sectional area of a vessel was larger or smaller than that of the proximal or distal reference segment. RESULTS: Nineteen of the 64 patients (29.7%) suffered from recurrence of ischemic events (group 1), whereas 45 patients (60.3%, group 2) remained free from symptoms. In univariate analyses, multivessel disease (42 versus 24%, P= 0.0236) and adaptive remodeling (63 versus 24%, P= 0.0032) were found to occur more commonly among patients in group 1. The patients in group 1 exhibited larger total vessel cross-sectional areas than did the patients in group 2 (17.5+/-4.2 versus 14.9+/-6.1 mm2, P = 0.0556). In multivariate regression analysis, adaptive remodeling proved to be a significant predictor (P = 0.0145) of the recurrence of ischemic events after thrombolysis of AMI. CONCLUSIONS: Adaptive remodeling of the infarct-related artery is associated with early postinfarction angina pectoris after thrombolysis of AMI.


Assuntos
Angina Pectoris/fisiopatologia , Vasos Coronários/lesões , Vasos Coronários/fisiopatologia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Terapia Trombolítica , Adulto , Idoso , Angina Pectoris/diagnóstico por imagem , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Estudos Prospectivos , Recidiva , Ultrassonografia
9.
J Nucl Med ; 42(2): 189-93, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11216515

RESUMO

UNLABELLED: This study evaluated the diagnostic accuracy of case-based reasoning (CBR) to automatically detect significant coronary artery disease from dipyridamole 201Tl myocardial SPECT perfusion scintigrams. METHODS: The study population included 240 patients (182 men, 58 women; mean age +/- SD, 61 +/- 12 y) on whom coronary angiography and perfusion scintigraphy were performed within 6 +/- 11 d of each other. The patients were divided into two groups according to the presence or absence of significant coronary disease in any major coronary vessel. Regional myocardial tracer uptake was observed in 84 segments by polar map analysis. For each scintigraphic image, a CBR algorithm based on a similarity metric was used to identify similar scintigraphic images within the case library. The angiographic results of these similar cases were used to obtain the CBR reading, which was compared with the true angiographic results. Myocardial scintigrams were also analyzed by a first-generation Cedars-Sinai (CS) method, including a comparison with a reference database, and by the visual analysis of an expert reader. RESULTS: By receiver-operating-characteristic analysis, the diagnostic accuracy of CBR was not different from the interpretation by the CS algorithm and from visual interpretation (P = not significant [NS]). For detection of significant coronary disease, the respective sensitivities at 50% and 80% specificity were 90% and 67% for CBR, 88% and 65% for CS polar map analysis, and 91% and 74% for visual interpretation. For the detection of coronary disease in the vascular territories assigned to the left anterior descending and the right coronary arteries, CBR and CS polar map analysis showed similar diagnostic accuracy (P = NS). However, for detection of disease in the circumflex artery, CS polar map analysis was slightly better than CBR (P = 0.03). CONCLUSION: Automated interpretation of dipyridamole 201Tl myocardial SPECT perfusion images by CBR has diagnostic accuracy similar to that of visual interpretation or CS analysis. Thus, use of a case library that includes a variety of normal and abnormal perfusion images does not appear to have greater diagnostic power than use of reference limits.


Assuntos
Circulação Coronária , Doença das Coronárias/diagnóstico por imagem , Dipiridamol , Sistemas Inteligentes , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
10.
J Agric Food Chem ; 48(11): 5184-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11087456

RESUMO

An analytical method for the determination of glufosinate ammonium and its principal metabolites, AE F064619 and AE F061517, in water of two different hardnesses (5 and 30 DH, French hardness) has been developed and validated. Samples were spiked at different levels (0. 05 and 0.5 microgram/L) and were purified by column chromatography on ion-exchange resins. After derivatization with glacial acetic acid and trimethylarthoacetate mixture, the derivatives were quantified by using capillary gas chromatography with an ion-trap tandem mass spectrometric detector. Analytical conditions for MS/MS detection were optimized, and the quantification was carried out on the areas of the most representative ions. The limit of quantification was validated at 0.05 microgram/L for each compound. The mean recovery value and the relative standard deviation (n = 20) were 92.0% and 17. 8% for glufosinate ammonium, 90.2% and 15.8% for AE F064619, and 89. 7% and 12.7% for AE F061517.


Assuntos
Acetatos/análise , Aminobutiratos/análise , Resíduos de Drogas/análise , Herbicidas/análise , Organofosfonatos/análise , Propionatos/análise , Água/análise , França , Cromatografia Gasosa-Espectrometria de Massas/métodos , Indicadores e Reagentes , Sensibilidade e Especificidade
11.
J Anal Toxicol ; 24(5): 365-71, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10926361

RESUMO

A rapid and single multimethod was developed to determine substances of different pesticide classes in whole blood in the event of acute human intoxications, as required by EU Commission Directive 96/46. The method was validated by an in-house and an independent laboratory validation. Whole blood is hemolyzed and then deproteinized. After extraction of the supernatant, blood levels are determined by gas chromatography-mass spectrometry. The method, which can be performed within 120 min, covers 15 active substances (8 organophosphate pesticides, 2 carbamates, 3 pyrethroids, 1 azole, and 1 organochlorine pesticide) classified as toxic or very toxic. These compounds can be identified down to concentrations between 100 and 1000 ng/mL by comparison of their mass spectra to those in a commercial pesticide mass spectra library. Using the standard addition method, they can be quantitated down to concentrations between 30 and 200 ng/mL. These limits of quantitation are considered to be sufficient in comparison to respective LD50 values.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/sangue , Medicina Legal/métodos , Humanos , Dose Letal Mediana , Praguicidas/intoxicação , Sensibilidade e Especificidade
12.
Am J Cardiol ; 84(6): 644-9, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10498132

RESUMO

A prospective, randomized, multicenter trial was conducted to evaluate whether high-pressure postdilation of the Wiktor stent provides short- and long-term benefits compared with the conventional low-pressure implantation technique. From June 1995 through May 1996, 181 patients were randomly assigned to either low-pressure (6 to 12 atm, group A, n = 94) Wiktor stent placement or to high-pressure postdilation (> or = 13 atm, group B, n = 87) after stent deployment. All patients were followed up clinically for 7 +/- 3 months, with an angiographic follow-up in 154 patients (85%). After stent implantation, neither minimal lumen diameter (MLD) nor percent diameter stenosis (%DS) differed significantly between the 2 groups (MLD, 2.8 +/- 0.5 vs 2.9 +/- 0.5 mm; %DS, 17 +/- 8% vs 16 +/- 9% for groups A and B, respectively). However, a trend toward a larger mean lumen diameter within the stent was observed in group B (3.3 +/- 0.6 vs 3.5 +/- 0.5 mm for groups A and B, respectively; difference between means 0.14 mm, 95% confidence interval -0.01 to 0.29, p = 0.08). Angiographic follow-up revealed similar MLD and %DS in both treatment groups (MLD, 2.1 +/- 0.7 vs 2.2 +/- 0.8 mm; %DS, 31 +/- 17% vs 30 +/- 24% for groups A and B, respectively, p = NS). Acute stent thrombosis occurred in 2 patients (1%) (1 patient in each group), and subacute thrombosis in 1 patient (0.6%) in group A. There was 1 death in group A, and target lesion restenosis (> or = 50% DS) was observed in 15% of patients with no differences between the groups. In conclusion, this study demonstrated favorable short- and long-term results of Wiktor stent implantation. Despite a trend toward additional initial lumen gain by high-pressure postdilation, this did not translate into a measurable improvement in long-term outcome.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença das Coronárias/terapia , Stents , Idoso , Doença das Coronárias/diagnóstico por imagem , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Estudos Prospectivos , Radiografia , Resultado do Tratamento
13.
Thromb Haemost ; 81(4): 522-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10235432

RESUMO

BACKGROUND: The main long-term complication of percutaneous transluminal coronary angioplasty (PTCA) is restenosis that occurs in 30-50 percent of all primary successful cases. The purpose of this study was to evaluate the predictive value of changes in plasminogen activator inhibitor-1 (PAI-1) activity and of thallium dipyridamole perfusion imaging performed 3 months after successful angioplasty. All patients were asymptomatic at evaluation. The results of these two noninvasive tests were compared with the angiographic outcome after 6 months. METHOD AND PATIENTS: Twenty-five patients were included in this prospective study. All patients had single vessel disease, successful angioplasty and were free of clinical symptoms 3 months after angioplasty that would suggest late restenosis. In 12/25 patients (48%) angiographic restenosis (percent diameter stenosis >50%) was determined by follow-up angiography 6 months after angioplasty. PAI-1 plasma activity was determined by a functional titration assay and increase or decrease of PAI-1 plasma activity was evaluated between values obtained before and 3 months after angioplasty. In 7/25 (28%) patients PAI-1 plasma activity increased to more than 90% of pre-angioplasty values. This increase correlated with angiographic restenosis evaluated 6 months after angioplasty (sensitivity 42%, specificity 85%, positive predictive value 71%, and negative predictive value 61%). T1-201-perfusion imaging was performed 3 months after angioplasty. This test was indicative for subsequent restenosis in 5/25 patients (sensitivity 33%, specificity 100%, positive predictive value 62%, and negative predictive value 100%). In 10/25 (40%) patients at least one of the two non-invasive tests performed 3 months after angioplasty predicted angiographic restenosis at 6 months: the combined use of PAI-1 and T1-201-perfusion imaging resulted in increased sensitivity (67%) and high specificity (85%). CONCLUSION: The results of this study indicate that an increase of PAI-1 plasma activity may improve the predictive value for restenosis of T1-201-scintigraphy performed 3 months after angioplasty even in asymptomatic patients.


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Coração/diagnóstico por imagem , Inibidor 1 de Ativador de Plasminogênio/sangue , Radioisótopos de Tálio , Doença das Coronárias/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cintilografia , Recidiva , Fatores de Risco
14.
J Am Coll Cardiol ; 32(6): 1701-8, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9822099

RESUMO

OBJECTIVES: We examined the relationship among viability assessment by dobutamine echocardiography (DE), positron emission tomography (PET) and thallium-201 single-photon emission computed tomography (TI-SPECT) to the degree of fibrosis. BACKGROUND: DE, PET and TI-SPECT have been shown to be sensitive in identifying viability of asynergic myocardium. However, PET and TI-SPECT indicated viability in a significant percentage of segments without dobutamine response or functional improvement after revascularization. METHODS: Twelve patients with coronary artery disease and severely reduced left ventricular function (EF 14.5+/-5.2%) were studied with DE prior to cardiac transplantation: 5 had additional PET and 7 had TI-SPECT studies. Results of the three techniques were compared to histologic findings of the explanted hearts. RESULTS: Segments with >75% viable myocytes by histology were determined to be viable in 78%, 89% and 87% by DE, PET and TI-SPECT; those with 50-75% viable myocytes in 71%, 50% and 87%, respectively. Segments with 25-50% viable myocytes showed response to dobutamine in only 15%, but were viable in 60% by PET and 82% by TI-SPECT. Segments with <25% viable myocytes responded to dobutamine in 19%; however, PET and TI-SPECT demonstrated viability in 33% and 38%, respectively. Discrepant segments without dobutamine response but viability by PET and SPECT had significantly more viable myocytes by pathology than did those classified in agreement to be nonviable but had significantly less viable myocytes than those classified in agreement to be viable (p < .001). CONCLUSIONS: These findings suggest that contractile reserve as evidenced by a positive dobutamine response requires at least 50% viable myocytes in a given segment whereas scintigraphic methods also identify segments with less viable myocytes. Thus, the methods may provide complementary information: Nuclear techniques appear to be highly sensitive for the detection of myocardial viability, and negative tests make it highly unlikely that a significant number of viable myocytes are present in a given segment. Conversely, dobutamine echo may be particularly useful for predicting recovery of systolic function after revascularization.


Assuntos
Doença das Coronárias/diagnóstico , Ecocardiografia , Sobrevivência de Tecidos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Idoso , Cardiotônicos , Doença das Coronárias/patologia , Doença das Coronárias/cirurgia , Dobutamina , Coração/diagnóstico por imagem , Transplante de Coração , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Radiografia , Radioisótopos de Tálio , Sobrevivência de Tecidos/fisiologia
15.
Clin Cardiol ; 21(4): 247-52, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9562934

RESUMO

BACKGROUND AND HYPOTHESIS: Recent studies demonstrate the feasibility of coronary flow reserve measurements by transesophageal echocardiographic (TEE) Doppler recordings of coronary sinus or left anterior descending (LAD) coronary artery flow velocity for detecting stenoses of the LAD artery. This study compares coronary flow reserve measurements by Doppler TEE with thallium-201 (201Tl) single-photon emission computed tomography (SPECT) in patients with proximal single-vessel LAD stenosis. METHODS: Nineteen patients with various degrees of LAD stenosis (mean area stenosis 71 +/- 24%; range 24-96%) were studied. Area stenosis by quantitative coronary angiography was < 75% in 7 patients and > 75% in 12 patients. Transesophageal LAD and coronary sinus Doppler measurements were performed at baseline and after intravenous dipyridamole. Coronary flow reserve was calculated as the ratio of hyperemic to baseline average peak velocities. Predefined coronary flow reserve cut-off values of 1.8 for the coronary sinus method and of 2.0 for the LAD method were used for diagnosis of significant LAD stenosis. Results were compared with qualitative 201Tl dipyridamole SPECT. RESULTS: Overall predictive accuracy for diagnosis of > 75% LAD stenosis was 79% for 201Tl SPECT, 77% for the transesophageal LAD and 79% for the transesophageal coronary sinus technique. Concordant results between 201Tl SPECT and the LAD and coronary sinus Doppler methods were observed in 79% and 71% of patients, respectively. CONCLUSIONS: Thallium-201 SPECT and transesophageal Doppler assessment of coronary flow reserve have similar accuracy for diagnosing significant proximal LAD stenosis. Therefore, both transesophageal Doppler techniques might constitute another widely available, noninvasive method for assessment of left coronary artery disease, if disease location is proximal.


Assuntos
Doença das Coronárias/diagnóstico , Vasos Coronários/fisiologia , Ecocardiografia Transesofagiana , Tomografia Computadorizada de Emissão de Fóton Único , Velocidade do Fluxo Sanguíneo , Angiografia Coronária , Doença das Coronárias/fisiopatologia , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Radioisótopos de Tálio
16.
Eur J Nucl Med ; 23(12): 1613-8, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8929315

RESUMO

Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent RNA were assessed with 2D-echo within 3 months. In addition, 92 of these patients also underwent CVG (correlation of ejection fraction between CVG and RNA: r=0.82; P<0.0001). The RNA mean ejection fractions in the four 2D-echo groups (0=normal, 1=slightly, 2=moderate, or 3=severe reduced left ventricular function) differed markedly (P<0.0001); however, there was overlapping among the groups (2D-echo score/RNA ejection fraction: 0=57.3%+/-12.8%; 1=46.0%+/-12.9%; 2=29.6%+/- 12.2%; and 3=24.6%+/-11. 5%) and the difference between 2D-echo scores 2 and 3 was not significant. 2D-echo showed a good concordance in RNA classes (0=>/=505; 1=35%-49%; 2=21%-34%; and 3=

Assuntos
Ecocardiografia , Imagem do Acúmulo Cardíaco de Comporta , Disfunção Ventricular Esquerda/diagnóstico por imagem , Cateterismo Cardíaco , Eritrócitos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Pertecnetato Tc 99m de Sódio , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
17.
Eur Heart J ; 17(12): 1852-9, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8960428

RESUMO

Clinical and experimental data have shown that after acute myocardial infarction there is a significant release of tumour necrosis factor alpha. Therefore, an attempt was made to correlate changes in serum tumour necrosis factor alpha concentrations with indices of infarct extent in patients with acute myocardial infarction. In 50 patients with acute myocardial infarction, blood samples for evaluation of tumour necrosis factor alpha and alpha-hydroxybutyrate-dehydrogenase were collected every 6 h until 120 h after admission. Infarct extent was estimated by clinical parameters such as the occurrence of heart failure and rhythm disturbances, by enzymatic methods such as cumulative release of alpha-hydroxybutyrate-dehydrogenase and imaging techniques, by late resting single photon emission tomography--201 thallium scintigraphy--using an extent score and by echocardiography using a wall motion index. The maximum change in serum tumour necrosis factor alpha after infarction (delta TNF) was calculated by subtracting tumour necrosis factor alpha concentration on admission from peak tumour necrosis factor alpha concentration. The average peak tumour necrosis factor alpha level was observed 84 h after admission (median: 12 pg.ml-1). Between the 72nd and the 96th h no significant changes in tumour necrosis factor alpha values were observed. Analysis of the data showed that larger delta (TNF) values were found to be associated significantly with signs of heart failure (P = 0.003), the presence of rhythm disturbances (P = 0.001), increased enzymatic infarct extent indicated by cumulative release of alpha-hydroxybutyrate-dehydrogenase (r = 0.74; P < 0.001), large myocardial perfusion defects measured with 201 thallium scintigraphy (r = 0.80; P < 0.001), and a considerable number of left ventricular wall motion abnormalities (r = 0.57; P < 0.001). In conclusion, delta (TNF) is a reliable method of assessing damage severity in the myocardium after acute myocardial infarction. As only two blood samples are necessary within 84 h, the method may be one of the more convenient for the assessment of infarct size in clinical practice.


Assuntos
Infarto do Miocárdio/patologia , Fator de Necrose Tumoral alfa/análise , Adulto , Idoso , Angiografia Coronária , Ecocardiografia , Estudos de Avaliação como Assunto , Feminino , Humanos , Escala de Gravidade do Ferimento , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Prognóstico , Sensibilidade e Especificidade , Fator de Necrose Tumoral alfa/metabolismo
18.
Eur Heart J ; 17(8): 1167-74, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8869857

RESUMO

UNLABELLED: Visual judgment of stenosis severity from cine-film or single-photon emission computed tomographic dipyridamole perfusion images was compared to assessment of stenosis severity as measured with digital quantitative coronary angiography. Thirty patients with angiographically verified single-vessel disease underwent dipyridamole thallium stress testing within 90 days of angiography. RESULTS: A percent diameter stenosis of > or = 50%, a percent area stenosis of > or = 75%, and a stenotic flow reserve of < 3.75 measured by quantitative coronary angiography (CMS, version 1.1, Medis Inc.) corresponded to haemodynamically significant stenosis as evaluated by visual estimates from cine-film or perfusion images. Quantitative coronary angiography percent diameter stenosis (51.2% +/- 12.6%) correlated closely (r = 0.74) but underestimated significantly visual assessment of stenosis severity from cine-film (69.3% +/- 21.2%; P = 0.0001). However, quantitative coronary angiography percent area stenosis (74.7% +/- 11.7%) more closely reflected visual estimates from cine-film (P = 0.19). Quantitative coronary angiography stenotic flow reserve showed the highest positive and negative predictive value regarding visual estimates from cine-film (88%, 86%) or perfusion images (88%, 64%) followed by percent diameter stenosis (86%, 75% 86%, 56%) and percent area stenosis (87%, 80%, 87%, 60%), respectively. CONCLUSION: Evaluation of coronary lesions by quantitative coronary angiography corresponds closely with visual estimates from cine-film and haemodynamic significance as evaluated by dipyridamole perfusion images.


Assuntos
Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Dipiridamol , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vasodilatadores , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Doença das Coronárias/fisiopatologia , Progressão da Doença , Teste de Esforço/métodos , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vasodilatação
19.
Z Kardiol ; 84(2): 81-5, 1995 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-7717021

RESUMO

BACKGROUND AND METHOD: After the introduction of coronary angioplasty in the late 1970s, diagnostic coronary angiography has been performed for reasons other than to evaluate patients for bypass surgery. The aim of this study was to evaluate the change of the patient-profile at the time of the first angiographic evaluation of coronary artery disease. Therefore, 6456 patients in the period from 1975 to 1989 were included. RESULTS: The observation period of 15 years was divided into three parts of 5 years each (group 1 1975-79, N = 1130); group 2 1980-84, N = 2412; and group 3 1984-89, N = 2914). The mean age (53.3 +/- 7.4 vs. 54.4 +/- 8.4 vs. 57.8 +/- 9.3; p < 0,0001) as well as the number of patients of age > 64 years (6.4% vs. 9.6% vs. 25.9%, p < 0.0001) increased significantly over the 15 years. Women were found twice as often in group 3 vs. group 1 (10% vs. 16% vs. 19%; p < 0.0001). In the observation period the left ventricular ejection fraction (51.1 +/- 15.9 vs. 53.8 +/- 14.4 vs. 55.4 +/- 16.2) and one-vessel disease (37.2% vs. 38.2% vs. 42.4%) increased significantly (p < 0.0001), whereas multi-vessel disease decreased (57.7% vs. 56.6% vs. 52.6%). CONCLUSION: Between 1975 and 1989 significantly more women, more patients over 64 years of age, and more patients with lower degree of coronary disease were first evaluated with coronary angiography. The change of patient-profile may have been influenced by increased risk-factors among women and the possibility to offer patients an alternative therapy to bypass surgery.


Assuntos
Angiografia Coronária , Doença das Coronárias/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão , Áustria/epidemiologia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Função Ventricular Esquerda/fisiologia
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