RESUMEN
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.
Asunto(s)
Cardiopatías/diagnóstico por imagen , Imagen de Perfusión Miocárdica/instrumentación , Tomografía de Emisión de Positrones/instrumentación , Generadores de Radionúclidos/instrumentación , Radioisótopos de Rubidio , Radioisótopos de Estroncio , Humanos , Garantía de la Calidad de Atención de Salud , Estudios RetrospectivosRESUMEN
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.
Asunto(s)
Circulación Coronaria , Medicina Nuclear , Tomografía de Emisión de Positrones/métodos , Sociedades Médicas , Adulto , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Humanos , Procesamiento de Imagen Asistido por Computador , Japón , Persona de Mediana Edad , Estrés FisiológicoAsunto(s)
Cardiología/normas , Enfermedades Cardiovasculares/diagnóstico por imagen , Circulación Coronaria , Imagen de Perfusión Miocárdica/métodos , Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones/normas , Flujo Sanguíneo Regional , Amoníaco , Sistema Cardiovascular , Ensayos Clínicos como Asunto , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Humanos , Procesamiento de Imagen Asistido por Computador , Radioisótopos de Nitrógeno , Pronóstico , Radiofármacos , Valores de Referencia , Reproducibilidad de los Resultados , Radioisótopos de Rubidio , Sociedades Médicas , Estados UnidosAsunto(s)
Predicción , Medicina Nuclear/normas , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/normas , Cintigrafía/normas , Sociedades Médicas/organización & administración , Medicina Nuclear/organización & administración , Medicina Nuclear/tendencias , Garantía de la Calidad de Atención de Salud/tendencias , Cintigrafía/tendencias , Estados UnidosRESUMEN
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.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Corazón/diagnóstico por imagen , Tecnecio Tc 99m Sestamibi/administración & dosificación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Anciano de 80 o más Años , Circulación Coronaria , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
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.
Asunto(s)
Circulación Coronaria , Muerte Súbita Cardíaca , Prueba de Esfuerzo , Frecuencia Cardíaca , Tomografía Computarizada de Emisión de Fotón Único , Factores de Edad , Enfermedades Cardiovasculares/mortalidad , Supervivencia sin Enfermedad , Humanos , Mortalidad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
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.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Cardiología/tendencias , Enfermedad de la Arteria Coronaria/diagnóstico , Prueba de Esfuerzo/métodos , Humanos , Imagenología Tridimensional , Medicina Nuclear/tendencias , Pronóstico , Factores de Riesgo , Tecnecio , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
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