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INTRODUCTION: Strontium-82/Rubidium-82 (82Sr/82Rb) generators are used widely for positron emission tomography (PET) imaging of myocardial perfusion. In this study, the 82Rb isotope yield and production efficiency of two FDA-approved 82Sr/82Rb generators were compared. METHODS: N = 515 sequential daily quality assurance (QA) reports from 9 CardioGen-82® and 9 RUBY-FILL® generators were reviewed over a period of 2 years. A series of test elutions was performed at different flow-rates on the RUBY-FILL® system to determine an empirical correction-factor used to convert CardioGen-82® daily QA values of 82Rb activity (dose-calibrator 'maximum' of 50 mL elution at 50 mL·min-1) to RUBY-FILL® equivalent values (integrated 'total' of 35 mL elution at 20 mL·min-1). The generator yield (82Rb) and production efficiency (82Rb yield/82Sr parent activity) were measured and compared after this conversion to a common scale. RESULTS: At the start of clinical use, the system reported 82Rb activity from daily QA was lower for CardioGen-82® vs RUBY-FILL® (2.3 ± 0.2 vs 3.0 ± 0.2 GBq, P < 0.001) despite having similar 82Sr activity. Dose-calibrator 'maximum' (CardioGen-82®) values were found to under-estimate the integrated 'total' (RUBY-FILL®) activity by ~ 24% at 50 mL·min-1. When these data were used to convert the CardioGen-82 values to a common measurement scale (integrated total activity) the CardioGen-82® efficiency remained slightly lower than the RUBY-FILL® system on average (88 ± 4% vs 95 ± 4%, P < 0.001). The efficiency of 82Rb production improved for both systems over the respective periods of clinical use. CONCLUSIONS: 82Rb generator yield was significantly under-estimated using the CardioGen-82® vs RUBY-FILL® daily QA procedure. When generator yield was expressed as the integrated total activity for both systems, the estimated 82Rb production efficiency of the CardioGen-82® system was ~ 7% lower than RUBY-FILL® over the full period of clinical use.
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Cardiopatias/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/instrumentação , Tomografia por Emissão de Pósitrons/instrumentação , Geradores de Radionuclídeos/instrumentação , Radioisótopos de Rubídio , Radioisótopos de Estrôncio , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Estudos RetrospectivosRESUMO
The above position statement originally published containing errors in the author metadata; specifically, the Expert Content Reviewers-Andrew Einstein, Raymond Russell and James R. Corbett-were tagged as full authors of the paper. The article metadata has now been corrected to remove Drs. Einstein, Russell and Corbett from the author line, and the PubMed record has been updated accordingly.
Assuntos
Cardiologia/normas , Doenças Cardiovasculares/diagnóstico por imagem , Circulação Coronária , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/normas , Fluxo Sanguíneo Regional , Amônia , Sistema Cardiovascular , Ensaios Clínicos como Assunto , Doença da Artéria Coronariana/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Humanos , Processamento de Imagem Assistida por Computador , Radioisótopos de Nitrogênio , Prognóstico , Compostos Radiofarmacêuticos , Valores de Referência , Reprodutibilidade dos Testes , Radioisótopos de Rubídio , Sociedades Médicas , Estados UnidosAssuntos
Previsões , Medicina Nuclear/normas , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde/normas , Cintilografia/normas , Sociedades Médicas/organização & administração , Medicina Nuclear/organização & administração , Medicina Nuclear/tendências , Garantia da Qualidade dos Cuidados de Saúde/tendências , Cintilografia/tendências , Estados UnidosRESUMO
OBJECTIVES: We sought to determine whether chronotropic incompetence (CI) adds incremental value in predicting cardiac death (CD) and all-cause mortality and to determine which marker of CI is superior. BACKGROUND: Chronotropic incompetence, defined by either a low percent heart rate (HR) reserve achieved or failure to achieve 85% maximal age-predicted heart rate (MA-PHR), is a predictor of mortality. These variables have not been examined together in a comprehensive myocardial perfusion single-photon emission computed tomographic (SPECT), or MPS, model. METHODS: A total of 10,021 patients who underwent exercise MPS, evaluated by a summed stress score (SSS), were followed up for 719 +/- 252 days. Percent HR reserve = (peak HR - rest HR)/(220 - age - rest HR) x 100, with <80% considered abnormal. RESULTS: A total of 2,956 patients (29.5%) had low %HR reserve; 1,331 (13.3%) achieved <85% MA-PHR; and 1,296 (13.0%) had both. There were 234 deaths (93 CDs). On multivariate analysis, the SSS, %HR reserve, and inability to achieve 85% MA-PHR were predictors of all-cause mortality and CD (all p < 0.01). Myocardial perfusion SPECT was the most powerful predictor of CD (chi-square = 50). When the %HR reserve and ability to achieve 85% MA-PHR were considered, only the former remained a predictor of CD (p = 0.006 vs. p = 0.59). CONCLUSIONS: In a comprehensive MPS model, CI was an important predictor of CD and all-cause mortality. Percent HR reserve was superior to the ability to achieve 85% MA-PHR in predicting CD; MPS was superior to both. Combined with previous studies, the findings suggest that %HR reserve should become the standard for assessing the adequacy of HR response during exercise testing, and that it should be routinely incorporated in risk stratification algorithms.
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Circulação Coronária , Morte Súbita Cardíaca , Teste de Esforço , Frequência Cardíaca , Tomografia Computadorizada de Emissão de Fóton Único , Fatores Etários , Doenças Cardiovasculares/mortalidade , Intervalo Livre de Doença , Humanos , Mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Taxa de SobrevidaAssuntos
Circulação Coronária , Medicina Nuclear , Tomografia por Emissão de Pósitrons/métodos , Sociedades Médicas , Adulto , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Japão , Pessoa de Meia-Idade , Estresse FisiológicoRESUMO
BACKGROUND: The clinical usefulness of a rapid rest low-dose/stress high-dose (dose ratio =1:5) (99m)Tc-sestamibi myocardial perfusion single-photon emission computed tomography (SPECT) protocol for the detection of coronary artery disease was evaluated. METHODS AND RESULTS: In 89 patients, rest images were obtained immediately after the injection of (99m)Tc-sestamibi (256.1+/-28.4 MBq) followed by drinking water (400 ml). Exercise or vasodilator stress test was performed immediately after the completion of rest imaging with the injection of (99m)Tc-sestamibi (1312.3 +/-167.6 MBq). Prior to the post-stress imaging, patients were asked again to drink water (400 ml) in order to eliminate subdiaphragmatic tracer activity. The myocardial count ratio (stress/rest) of (99m)Tc-sestamibi was calculated. Image quality was scored using a 4-point scale system (4= excellent, 3= good, 2= poor, 1= unacceptable). Coronary angiography was performed in 56 patients within 1 month of the SPECT scan. All patients successfully performed the protocol and total examination time was 108+/-7 min. The myocardial count ratio of (99m)Tc-sestamibi was always greater than 6. The image quality was satisfactory both at rest (3.4+/-0.9) and after stress (3.9+/-0.2). The sensitivity and specificity to detect coronary artery stenosis >50% was 84% and 97%, respectively. CONCLUSIONS: This rapid one-day (99m)Tc-sestamibi protocol provides adequate image quality and diagnostic accuracy for detecting coronary artery disease.
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Doença da Artéria Coronariana/diagnóstico por imagem , Coração/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi/administração & dosagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Circulação Coronária , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
Myocardial perfusion single photon emission computed tomography (SPECT) is a widely utilized noninvasive imaging modality for the diagnosis, prognosis, and risk stratification of coronary artery disease. It is clearly superior to the traditional planar technique in terms of imaging contrast and consequent diagnostic and prognostic yield. The strength of SPECT images is largely derived from the three-dimensional, volumetric nature of its image. Thus, this modality permits three-dimensional assessment and quantitation of the perfused myocardium and functional assessment through electrocardiographic gating of the perfusion images.
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Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Cardiologia/tendências , Doença da Artéria Coronariana/diagnóstico , Teste de Esforço/métodos , Humanos , Imageamento Tridimensional , Medicina Nuclear/tendências , Prognóstico , Fatores de Risco , Tecnécio , Tomografia Computadorizada de Emissão de Fóton Único/métodosRESUMO
BACKGROUND: Little is known about the prognostic value of myocardial perfusion single photon emission computed tomography (SPECT) in patients with remote prior myocardial infarction (MI). METHODS AND RESULTS: We identified 1413 consecutive patients with remote prior MI who underwent rest-stress myocardial perfusion SPECT. Semiquantitative visual analysis of 20 SPECT segments was used to define the summed stress, rest, and difference scores. The number of non-reversible segments was used as an index of infarct size. During follow-up (>or=1 year), 118 hard events occurred: 64 cardiac deaths (CDs) and 54 recurrent MIs. Annual CD and hard event rates increased significantly as a function of SPECT abnormality. For summed stress scores less than 4, 4 to 8, 9 to 13, and more than 13, the annual CD rates were 0.4%, 0.9%, 1.7%, and 3.5%, respectively (P =.002). Patients with small MI (<4 non-reversible segments) and no or mild ischemia (summed difference score