Implantación de un protocolo de angio-TC coronaria basado en el índice de masa corporal: reducción de dosis, calidad de imagen y rendimiento diagnóstico / Implementing a coronary CT angiography protocol based on the body mass index: radiation dose reduction, image quality, and diagnostic performance

Objetivos: Valorar la relación entre el score de calcio coronario y la elección posterior del kilovoltaje según el criterio del radiólogo en un protocolo estándar (PE) de angio-TC coronaria (aTCC) para descartar enfermedad coronaria. Cuantificar la reducción de la radiación ionizante después de vincular el kilovoltaje al índice de masa corporal en un protocolo de baja dosis (PBD) con reconstrucción iterativa de modelado. Valorar la calidad de imagen y el rendimiento diagnóstico del PBD. Material y método: Las características antropométricas, el score de calcio, los niveles de kilovoltaje y los valores de dosis estimada específica para el tamaño (SSDE) y del producto dosis-longitud fueron comparados entre un grupo de 50 pacientes con PBD reclutados prospectivamente y una cohorte histórica adquirida con el PE. Estos parámetros, el número de segmentos coronarios no valorables sin y con tolerancia de fase, la atenuación y la relación señal-ruido en la aorta ascendente en el PBD fueron correlacionados con una calidad de imagen de nivel excelente según una escala semicuantitativa. El rendimiento diagnóstico por paciente fue calculado usando la revaloración clínica a los 24 meses como el método diagnóstico de referencia, incluyendo las pruebas derivadas. Resultados: En el PE existía una relación entre la presencia de calcio coronario y la elección de kilovoltajes altos (p=0,02), que desaparecía en el PBD (p=0,47). Los valores de SSDE y de DLP en el PBD fueron significativamente inferiores y presentaron menor dispersión que en el PE (9,22 mGy [RIQ 7,84-12,1 mGy] y 97 mGy*cm [RIQ 78-134 mGy*cm] contra 26,5 mGy [RIQ 21,3-36,3 mGy] y 253 mGy*cm [RIQ 216-404 mGy*cm]; p <0,001 para las comparaciones de las medianas y de las dispersiones entre ambos grupos)...(AU)

Objectives: To evaluate the relation between the coronary calcium score and the posterior choice of kilovoltage according to radiologists’ criteria in a standard coronary CT angiography protocol to rule out coronary disease. To quantify the reduction in ionizing radiation after linking kilovoltage to patients’ body mass index in a low-dose protocol with iterative model reconstruction. To evaluate the image quality and diagnostic performance of the low-dose protocol. Material and methods: We compared anthropometric characteristics, calcium score, kilovoltage levels, size-specific dose estimates (SSDE), and the dose-length product (DLP) between a group of 50 patients who were prospectively recruited to undergo coronary CT angiography with a low-dose protocol and a historical group of 50 patients who underwent coronary CT angiography with the standard protocol. We correlated these parameters, the number of coronary segments that could not be evaluated with and without temporal padding, the attenuation, and the signal-to-noise ratio in the ascending aorta in the low-dose protocol with excellent imaging quality according to a semiquantitative scale. To calculate the diagnostic performance per patient, we used 24-month clinical follow-up including all tests as the gold standard. Results: In the standard protocol, the presence of coronary calcium correlated with the selection of high kilovoltage (P=0.02); this correlation was not found in the low-dose protocol (P=0.47). Median values of SSDE and DLP were significantly (P<0.001) lower and less dispersed in the low-dose protocol [9.22 mGy (IQR 7.84-12.1 mGy) vs. 26.5 mGy (IQR 21.3-36.3 mGy) in the standard protocol] and [97mGy*cm (IQR 78-134mGy*cm) vs. 253mGy*cm (IQR 216-404mGy*cm) in the standard protocol], respectively...(AU)

Implementing a coronary CT angiography protocol based on the body mass index: Radiation dose reduction, image quality, and diagnostic performance.

OBJECTIVES: To evaluate the relation between the coronary calcium score and the posterior choice of kilovoltage according to radiologists' criteria in a standard coronary CT angiography protocol to rule out coronary disease. To quantify the reduction in ionizing radiation after linking kilovoltage to patients' body mass index in a low-dose protocol with iterative model reconstruction. To evaluate the image quality and diagnostic performance of the low-dose protocol. MATERIAL AND METHODS: We compared anthropometric characteristics, calcium score, kilovoltage levels, size-specific dose estimates (SSDE), and the dose-length product (DLP) between a group of 50 patients who were prospectively recruited to undergo coronary CT angiography with a low-dose protocol and a historical group of 50 patients who underwent coronary CT angiography with the standard protocol. We correlated these parameters, the number of coronary segments that could not be evaluated with and without temporal padding, the attenuation, and the signal-to-noise ratio in the ascending aorta in the low-dose protocol with excellent imaging quality according to a semiquantitative scale. To calculate the diagnostic performance per patient, we used 24-month clinical follow-up including all tests as the gold standard. RESULTS: In the standard protocol, the presence of coronary calcium correlated with the selection of high kilovoltage (p = 0.02); this correlation was not found in the low-dose protocol (p = 0.47). Median values of SSDE and DLP were significantly (p < 0.001) lower and less dispersed in the low-dose protocol [9.22 mGy (IQR 7.84-12.1 mGy) vs. 26.5 mGy (IQR 21.3-36.3 mGy) in the standard protocol] and [97 mGy cm (IQR 78-134 mGy cm) vs. 253 mGy cm (IQR 216-404 mGy cm) in the standard protocol], respectively. The overall quality of the images obtained with the low-dose protocol was considered good or excellent in 96% of the studies. The parameters associated with image quality in a multivariable model (C statistic = 0.792) were heart rate (estimated coefficient, -0,12 [95% confidence interval: -0.2, -0.04]; p < 0.01) and the SSDE (estimated coefficient, -0,26 [95% confidence interval: -0.51, -0.01]; p < 0.05). The CAD-RADS modifier for a not fully evaluable or diagnostic study was used on two occasions (4%); the final measures for the diagnosis of coronary disease were sensitivity 100%, specificity 94%, and efficacy 94%. CONCLUSIONS: In the standard protocol, the radiologist selects higher kilovoltage for CT angiography studies for patients whose previous calcium score indicates the presence of coronary calcium. In the low-dose protocol, linking kilovoltage with body mass index enables the dose of radiation to be reduced by 65% while obtaining excellent or good image quality in 96% of studies and excellent diagnostic performance.

Integración de los parámetros de remodelado, sincronía y velocidad máxima de vaciado para evaluar la función sistólica del ventrículo izquierdo / Integration of ventricular remodeling, synchrony and filling rate parameters to improve the assessment of left ventricular systolic function

Objetivos El objetivo es estudiar la relación entre los parámetros estructurales, de remodelado, de sincronía y de función sistólica del ventrículo izquierdo (VI) mediante gSPECT. Obtener los valores de corte del VI para el índice de la forma telediastólica (iFTD), el índice de la forma telesistólica (iFTS), el índice de excentricidad (iEX) y la velocidad máxima de vaciado (VMV). Desarrollar un nuevo índice para evaluar diferentes patrones de función sistólica del VI. Material y métodos Analizamos prospectivamente 238 pacientes (edad: 63,4±13 años) estudiados mediante gSPECT de esfuerzo-reposo (grupo-control, n=148; pacientes con infarto de miocardio [IM] previo, n=90). Estudio aprobado por el Comité de Ética del Hospital (PR[AG]168.2010). Resultados En el grupo-control, el índice del volumen telediastólico (iVTD) y el iEX influyeron en el iFTD (r2: 0,52, p<0,001). El iVTD, la VMV, ser varones y el iEX (r2: 0,44; p<0,001) influyeron en el iFTS. El iFTD, iFTS, la fracción de eyección VI (FEVI) y el volumen de eyección sistólica (r2: 0,62; p<0,001) influyeron en el iEX. La FEVI, la frecuencia cardíaca, el ancho de banda (AB) y la desviación estándar influyeron (r2: 0,76; p<0,001) en la VMV. Los valores de corte para iFTD, iFTS, iEX y VMV fueron 0,59, 0,42, 0,87 y −3,3 respectivamente. La VMV, el iFTS y el AB fueron los parámetros mejor relacionados con los pacientes con IM previo (AUC: 0,89), y sumados a la FEVI permitieron obtener distintos patrones de función sistólica (índice PERRS). Conclusiones Los parámetros de remodelado, sincronía y función sistólica del VI deben interpretarse simultáneamente, ya que esto permite obtener distintos patrones de función sistólica del VI (AU)

Introduction and objectives The aim of this study is to assess the relationship between structural, remodeling, synchrony, and systolic left ventricular (LV) function parameters using gated-SPECT myocardial-perfusion-images (gSPECT-MPI). In addition, obtaining the cut-off values for end-diastolic LV-shape-index (EDLVsi), end-systolic LV-shape-index (ESLVsi), ECC (eccentricity-index) and PER, and developing a new index to evaluate different patterns of the LV systolic function. Methods The study was approved by the Hospital's Ethical-Committee (PR[AG]168.2010), and all patients gave their informed consent. We analyzed prospectively 238 patients (age 63.4±13 years) who underwent stress-rest gSPECT-MPI (control-group, n=148; patients with previous myocardial infarction [MI], n=90). Results In the control group, with regard to remodeling parameters: the end-diastolic-volume-index (EDV) and the ECC were the parameters that influenced the EDLVsi (r2: 0.52, P<.001). EDV, PER, men, and the ECC were the parameters (r2: 0.44; P<.001) which influenced the ESLVsi. EDLVsi, ESLVsi, LVEF and the stroke-volume were the parameters (r2: 0.62; P<.001) which influenced the ECC. With regards to PER: LVEF, heart-rate, bandwidth, and the standard-deviation were the influencing parameters (r2: 0.76; P<.001). The cut-off values for EDLVsi, ESLVsi, ECC, and PER were 0.59, 0.42, 0.87, and 3.3, respectively. The PER, the ESLVsi and the bandwidth were the parameters related to patients with previous MI (AUC: 0.89); and they allow the assessment of different patterns of systolic function (PERRS-index: Peak-Emptying-Rate, left ventricular-Remodeling and Synchrony). Conclusions The remodeling, synchrony and the systolic function parameters of the LV should be interpreted together (PERRS-index). In this way, we obtain different patterns of LV systolic function (AU)

Integration of ventricular remodeling, synchrony and filling rate parameters to improve the assessment of left ventricular systolic function.

INTRODUCTION AND OBJECTIVES: The aim of this study is to assess the relationship between structural, remodeling, synchrony, and systolic left ventricular (LV) function parameters using gated-SPECT myocardial-perfusion-images (gSPECT-MPI). In addition, obtaining the cut-off values for end-diastolic LV-shape-index (EDLVsi), end-systolic LV-shape-index (ESLVsi), ECC (eccentricity-index) and PER, and developing a new index to evaluate different patterns of the LV systolic function. METHODS: The study was approved by the Hospital's Ethical-Committee (PR[AG]168.2010), and all patients gave their informed consent. We analyzed prospectively 238 patients (age 63.4 ±â€¯13 years) who underwent stress-rest gSPECT-MPI (control-group, n = 148; patients with previous myocardial infarction [MI], n = 90). RESULTS: In the control group, with regard to remodeling parameters: the end-diastolic-volume-index (EDV) and the ECC were the parameters that influenced the EDLVsi (r2: 0.52, p < 0.001). EDV, PER, men, and the ECC were the parameters (r2: 0.44; p < 0.001) which influenced the ESLVsi. EDLVsi, ESLVsi, LVEF and the stroke-volume were the parameters (r2: 0.62; p < 0.001) which influenced the ECC. With regards to PER: LVEF, heart-rate, bandwidth, and the standard-deviation were the influencing parameters (r2: 0.76; p < 0.001). The cut-off values for EDLVsi, ESLVsi, ECC, and PER were 0.59, 0.42, 0.87, and 3.3, respectively. The PER, the ESLVsi and the bandwidth were the parameters related to patients with previous MI (AUC: 0.89); and they allow the assessment of different patterns of systolic function (PERRS-index: peak-emptying-rate, left ventricular-remodeling and synchrony). CONCLUSIONS: The remodeling, synchrony and the systolic function parameters of the LV should be interpreted together (PERRS-index). In this way, we obtain different patterns of LV systolic function.

Descripción de un método de cuantificación diferente para la carga de amiloide (DPDload) y validación de SPECT/TC en amiloidosis cardíaca / Description of a different quantification method for amyloid burden (burdenDPD) and validation of SPECT/CT in cardiac amyloidosis

Introducción Los radiotrazadores con afinidad ósea como el [99mTc]Tc-DPD han demostrado una alta sensibilidad y especificidad en el diagnóstico no invasivo de la amiloidosis cardíaca (AC) por transtirretina (ATTR-AC). Este estudio tiene como objetivo validar el uso de la SPECT/TC y evaluar la utilidad de la cuantificación de la captación (cargaDPD) en el tejido miocárdico como información potencial sobre la carga amiloide. Métodos Se trata de un análisis retrospectivo de 46 pacientes con sospecha de AC, en el que 23 casos con ATTR-AC fueron sometidos a dos métodos de cuantificación para estimar la carga amiloide (cargaDPD) a través de imágenes planares y de una SPECT/TC. Resultados La SPECT/TC aportó un valor añadido significativo en el diagnóstico del paciente con AC (p<0,05). La estimación de la carga amiloide comprobó que la pared del VI más afectada es el tabique interventricular en la mayoría de los casos, y la existencia de una relación significativa entre la captación de Perugini y la carga de DPD. Conclusiones Validamos la necesidad de la SPECT/TC como complemento de la imagen planar en el diagnóstico de la AC-TTR. Por su parte, el cálculo de la carga amiloide continúa siendo un área de investigación compleja y requiere de más estudios, con un mayor número de pacientes, que permitan validar un método estandarizado de cuantificación de la carga de amiloide, tanto para el diagnóstico como para el seguimiento del tratamiento (AU)

Background Bone tracers such as [99mTc]Tc-DPD have shown high sensitivity and specificity in the non-invasive diagnosis of transthyretin cardiac amyloidosis (ATTR-AC). This study aims to validate SPECT/CT and assess the usefulness of uptake quantification (burdenDPD) in the myocardial tissue as potential information on the amyloid burden. Methods In a retrospective analysis of 46 patients with suspected CA, 23 cases with ATTR-AC had two quantification methods conducted to estimate amyloid burden (burdenDPD) through planar scintigraphic scans and a SPECT/CT. Results SPECT/CT significantly provided an added value in the patient's diagnosis with CA (P<.05). The estimation of the amyloid burden substantiated that the most affected wall of the LV is the interventricular septum in most cases and the existence of a significant relationship between the Perugini score uptake and the burdenDPD. Conclusions We validate the need for SPECT/CT to complement planar imaging in diagnosing ATTR-AC. For its part, quantifying the amyloid load continues to be a complex area of research. It requires further studies with a larger number of patients to validate a standardized method of amyloid load quantification, both for diagnosis and treatment monitoring (AU)

Coste-efectividad de la SPECT de perfusión miocárdica y de la prueba de esfuerzo en relación con la revascularización coronaria, eventos cardíacos y mortalidad total. Registro de 8.496 pacientes / Cost-effectiveness of myocardial perfusion SPECT and stress test according to coronary revascularization therapy, cardiac events and total mortality: Register of 8,496 patients

OBJETIVO: Análisis de la relación coste-efectividad (RCE) del electrocardiograma de esfuerzo y de la SPECT de perfusión miocárdica esfuerzo-reposo en relación con la revascularización coronaria (RC), eventos cardíacos (EC) y mortalidad total (MT). MATERIAL Y MÉTODOS: Se estudiaron 8.496 pacientes con SPECT y seguimiento medio de 5,3±3,5años. Evaluamos la RCE para la RC quirúrgica (RCQ) y percutánea (RCP) (45,6%/54,4%) de acuerdo con los resultados de la isquemia electrocardiográfica y gammagráfica. La efectividad se evaluó como MT, EC, LYSO (life-year-saved-observed) y EC-LYSO. Los análisis de costes se realizaron desde la perspectiva del pagador de atención médica. El análisis de sensibilidad fue considerando las relaciones RCQ/RCP actuales (12%/88%). RESULTADOS: Al combinar los resultados del electrocardiograma de esfuerzo y de la gammagrafía, los valores de coste-efectividad para la RCQ variaron entre 112.589€ (isquemia electrocardiográfica y gammagráfica) y 2.814.715€ (sin isquemia)/evento evitado, y entre 38.664 y 2.221.559€/LYSO; y para la RCP entre 18.824€ (isquemia electrocardiográfica y gammagráfica) y 46.377€ (sin isquemia)/evento evitado, y entre 6.464 y 36.604€/LYSO. Para el EC: los valores de coste-efectividad de la RCQ y RCP en presencia de isquemia electrocardiográfica y gammagráfica fueron de 269.904€/EC evitado y de 24.428€/EC evitado, respectivamente; y los €/LYSO de la RCQ y RCP fueron de 152.488 y 13.801, respectivamente. Se mantuvo la misma RCE para la proporción actual de pacientes revascularizados (12%/88%). CONCLUSIONES: El análisis combinado de las imágenes de la SPECT y del electrocardiograma de esfuerzo permite la diferenciación entre grupos de pacientes en donde la RCP y la RCQ son más rentables. La mayor RCE en relación con la RC, EC y MT se da en los pacientes con isquemia electrocardiográfica y gammagráfica. La RCP es más coste-efectiva que la RCQ

OBJECTIVE: The aim was to analyze the cost-effectiveness ratio (CER) of stress electrocardiogram (ES) and stress myocardial perfusion imaging (SPECT-MPI) according to coronary revascularization (CR) therapy, cardiac events (CE) and total mortality (TM). MATERIAL AND METHODS: A total of 8,496 consecutive patients who underwent SPECT-MPI were followed-up (mean 5.3±3.5years). Cost-effectiveness for coronary bypass (CABG) or percutaneous CR (PCR) (45.6%/54.4%) according to combined electrocardiographic ischemia and scintigraphic ischemia were evaluated. Effectiveness was evaluated as TM, CE, life-year saved observed (LYSO) and CE-LYSO; costs analyses were conducted from the perspective of the health care payer. A sensitivity analysis was performed considering current CABG/PCR ratios (12%/88%). RESULTS: When electrocardiogram and SPECT approaches are combined, the cost-effectiveness values for CABG ranged between 112,589€ (electrocardiographic and scintigraphic ischemia) and 2,814,715€ (without ischemia)/event avoided, 38,664 and 2,221,559€/LYSO; for PCR ranged between 18,824€ (electrocardiographic and scintigraphic ischemia) and 46,377€ (without ischemia)/event avoided, 6,464 and 36,604€/LYSO. To CE: the cost-effectiveness values of the CABG and CPR in presence of electrocardiographic and scintigraphic ischemia were 269,904€/CE-avoided and 24,428€/CE-avoided, respectively; and the €/LYSO of the CABG and PCR were 152,488 and 13,801, respectively. The RCE was maintained for the current proportion of revascularized patients (12%/88%). CONCLUSIONS: Combined ES and SPECT-MPI results, allows differentiation between patient groups, where the PCR and CABG are more cost-effective in different economic frameworks. The major CER in relation to CR, CE and TM occurs in patients with electrocardiographic and scintigraphic ischemia. PCR is more cost-effective than CABG

Cost-effectiveness of myocardial perfusion SPECT and stress test according to coronary revascularization therapy, cardiac events and total mortality: Register of 8,496 patients. / Coste-efectividad de la SPECT de perfusión miocárdica y de la prueba de esfuerzo en relación con la revascularización coronaria, eventos cardíacos y mortalidad total. Registro de 8.496 pacientes.

OBJECTIVE: The aim was to analyze the cost-effectiveness ratio (CER) of stress electrocardiogram (ES) and stress myocardial perfusion imaging (SPECT-MPI) according to coronary revascularization (CR) therapy, cardiac events (CE) and total mortality (TM). MATERIAL AND METHODS: A total of 8,496 consecutive patients who underwent SPECT-MPI were followed-up (mean 5.3±3.5years). Cost-effectiveness for coronary bypass (CABG) or percutaneous CR (PCR) (45.6%/54.4%) according to combined electrocardiographic ischemia and scintigraphic ischemia were evaluated. Effectiveness was evaluated as TM, CE, life-year saved observed (LYSO) and CE-LYSO; costs analyses were conducted from the perspective of the health care payer. A sensitivity analysis was performed considering current CABG/PCR ratios (12%/88%). RESULTS: When electrocardiogram and SPECT approaches are combined, the cost-effectiveness values for CABG ranged between 112,589€ (electrocardiographic and scintigraphic ischemia) and 2,814,715€ (without ischemia)/event avoided, 38,664 and 2,221,559€/LYSO; for PCR ranged between 18,824€ (electrocardiographic and scintigraphic ischemia) and 46,377€ (without ischemia)/event avoided, 6,464 and 36,604€/LYSO. To CE: the cost-effectiveness values of the CABG and CPR in presence of electrocardiographic and scintigraphic ischemia were 269,904€/CE-avoided and 24,428€/CE-avoided, respectively; and the €/LYSO of the CABG and PCR were 152,488 and 13,801, respectively. The RCE was maintained for the current proportion of revascularized patients (12%/88%). CONCLUSIONS: Combined ES and SPECT-MPI results, allows differentiation between patient groups, where the PCR and CABG are more cost-effective in different economic frameworks. The major CER in relation to CR, CE and TM occurs in patients with electrocardiographic and scintigraphic ischemia. PCR is more cost-effective than CABG.

Metodología de la PET/TC con 18F-FDG cardíaca para el diagnóstico de la endocarditis protésica y de dispositivos intracardíacos / Cardiac 18F-FDG PET/CT procedure for the diagnosis of prosthetic endocarditis and intracardiac devices

La endocarditis infecciosa (EI) es una patología grave y con mal pronóstico cuya mortalidad no se ha modificado significativamente a pesar de los avances en su diagnóstico y tratamiento en los últimos 30años. La capacidad diagnóstica de los criterios de Duke modificados en la endocarditis protésica y/o de dispositivos no supera el 50%, por lo que se hacen necesarias nuevas herramientas para el diagnóstico de esta entidad en dicho contexto. La 18F-FDG PET/aTC combina una técnica con gran sensibilidad para detectar actividad inflamatoria-infecciosa y una técnica con gran resolución anatómica para valorar las lesiones estructurales asociadas a la endocarditis. Con una sensibilidad diagnóstica entre el 91 y el 97%, esta técnica híbrida se ha convertido en una herramienta de diagnóstico útil en la sospecha de EI de pacientes con válvulas protésicas o dispositivos, convirtiéndose en un criterio mayor en el algoritmo diagnóstico de las guías actuales. Esta excelente capacidad diagnóstica depende de forma directa de la calidad de la exploración obtenida y del conocimiento a la hora de interpretar las imágenes. El objetivo de esta revisión es describir y estandarizar la metodología de la 18F-FDG-PET/aTC cardíaca en el diagnóstico de endocarditis protésica y de dispositivos intracardíacos, haciendo especial énfasis en las particularidades de la preparación del paciente, de la adquisición de los estudios PET y TC, y del posterior posprocesado e interpretación de las imágenes

Infective endocarditis (IE) is a serious condition with a poor prognosis, its mortality unchanged significantly despite diagnostic and therapeutic advances in the last 30years. The diagnostic ability of the modified Duke criteria in prosthetic endocarditis and/or devices does not exceed 50%, so new tools are necessary for the diagnosis of this entity in this context. The 18F-FDG PET/CTA combines a highly sensitive technique to detect inflammatory-infectious activity with a technique with high anatomical resolution to assess the structural lesions associated with endocarditis. With a diagnostic sensitivity between 91-97%, this hybrid technique has become a useful diagnostic tool for patients with prosthetic valves or devices and suspicion of IE, becoming a major criterion in the diagnostic algorithm of current guidelines. This excellent diagnostic ability depends directly on the quality of the obtained exploration and the knowledge at the time of interpreting the images. The aim of this review is to describe and standardize the methodology of cardiac 18F-FDG PET/CTA in the diagnosis of endocarditis in prosthetic valves and intracardiac devices, with special emphasis on the particularities of the patient's preparation, the PET and CT acquisition procedures, and the subsequent imaging postprocessing and interpretation

Cardiac 18F-FDG PET/CT procedure for the diagnosis of prosthetic endocarditis and intracardiac devices. / Metodología de la PET/TC con 18F-FDG cardíaca para el diagnóstico de la endocarditis protésica y de dispositivos intracardíacos.

Infective endocarditis (IE) is a serious condition with a poor prognosis, its mortality unchanged significantly despite diagnostic and therapeutic advances in the last 30years. The diagnostic ability of the modified Duke criteria in prosthetic endocarditis and/or devices does not exceed 50%, so new tools are necessary for the diagnosis of this entity in this context. The 18F-FDG PET/CTA combines a highly sensitive technique to detect inflammatory-infectious activity with a technique with high anatomical resolution to assess the structural lesions associated with endocarditis. With a diagnostic sensitivity between 91-97%, this hybrid technique has become a useful diagnostic tool for patients with prosthetic valves or devices and suspicion of IE, becoming a major criterion in the diagnostic algorithm of current guidelines. This excellent diagnostic ability depends directly on the quality of the obtained exploration and the knowledge at the time of interpreting the images. The aim of this review is to describe and standardize the methodology of cardiac 18F-FDG PET/CTA in the diagnosis of endocarditis in prosthetic valves and intracardiac devices, with special emphasis on the particularities of the patient's preparation, the PET and CT acquisition procedures, and the subsequent imaging postprocessing and interpretation.

18F-FDG-PET/CT Angiography for the Diagnosis of Infective Endocarditis.

PURPOSE OF REVIEW: This article reviews the current imaging role of 18F-fluordeoxyglucose positron emission computed tomography (18F-FDG-PET/CT) combined with cardiac CT angiography (CTA) in infective endocarditis and discusses the strengths and limitations of this technique. RECENT FINDINGS: The diagnosis of infective endocarditis affecting prosthetic valves and intracardiac devices is challenging because echocardiography and, therefore, the modified Duke criteria have well-recognized limitations in this clinical scenario. The high sensitivity of 18F-FDG-PET/CT for the detection of infection associated with the accurate definition of structural damage by gated cardiac CTA in a combined technique (PET/CTA) has provided a significant increase in diagnostic sensitivity for the detection of IE. PET/CTA has proven to be a useful diagnostic tool in patients with suspected infective endocarditis. The additional information provided by this technique improves diagnostic performance in prosthetic valve endocarditis when it is used in combination with the Duke criteria. The findings obtained in PET/CTA studies have been included as a major criterion in the recently updated diagnostic algorithm in infective endocarditis guidelines.

Utilidad de la 18F-FDG PET/cardio-TC en el diagnóstico de endocarditis protésica aórtica tardía con absceso periprotésico / Diagnostic value of 18F-FDG PET/cardiac CT in late prosthetic aortic endocarditis with periprosthetic abscess

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El patrón de discordancia motilidad-perfusión en la gated-SPECT de reposo sugiere necrosis no transmural en la resonancia magnética cardiaca / Motion-perfusion mismatch-pattern on rest-gated SPECT suggests non-transmural necrosis on cardiac magnetic resonance

No disponible

Obtención de una fórmula que mejora la estimación del consumo máximo de oxígeno en las pruebas de esfuerzo con bicicleta ergométrica / Obtaining a formula that improves maximum oxygen consumption estimation in cycle ergometer exercise tests

Objetivos: Valorar si la estimación del consumo máximo de oxígeno (CMO2) en MET (unidad metabólica) mediante las tablas propuestas en las guías de la Sociedad Española de Cardiología (SEC) es un método suficientemente fiable cuando se aplica a las pruebas de esfuerzo con bicicleta ergométrica. Material y métodos: Se obtuvo el CMO2 en MET por consumo de gases en bicicleta ergométrica en 97 sujetos sanos (grupo i) y se comparó con la estimación de los MET obtenida mediante tabla en la que solo intervienen los vatios y el peso del paciente. Mediante la introducción de variables clínicas y ergométricas se obtuvo una fórmula con mejor ajuste para el cálculo de los MET validándose en 289 pacientes (grupo ii) con gated-SPECT de perfusión miocárdica normal. Resultados: En los individuos del grupo i se observó una buena correlación entre los MET estimados con la tabla y los MET obtenidos mediante consumo de gases (CCI: 0,93). Sin embargo, la fórmula con mejor ajuste para la estimación de los MET en los pacientes del grupo ii incluyó los vatios, el índice de masa corporal (IMC), la edad y el sexo (MET = 11,820 − 0,054 × edad − 0,189 × IMC + 1,031 × sexo + 0,020 × vatios) (mujer: 0, hombre: 1). Esta fórmula permitió la reclasificación de un 46,9% de los individuos del grupo ii en la categoría < 5 MET con respecto a la estimación por tabla. Conclusiones: La estimación de los MET mediante la tabla convencional es fiable, aunque el ajuste óptimo, cuando se aplica a sujetos con gated-SPECT de perfusión miocárdica de esfuerzo normal, se obtiene al considerar, además de los vatios, el IMC, la edad y el sexo (AU)

Objectives: To evaluate if the estimation of the maximal oxygen consumption (MO2C) in METs (metabolic equivalents) by means of the table proposed in the guidelines of the Spanish Society of Cardiology is a sufficiently reliable method when applied to the bicycle exercise test. Material and methods: The MO2C in METs was obtained by gas-exchange analysis on bicycle ergometer tests in 97 healthy subjects (group i). It was compared with the estimate of METs using the table in which only watts and patient's weight were included. A better-adjusted formula was validated in 289 subjects with normal exercise myocardial perfusion gated-SPECT (group ii) using the introduction of clinical and ergometric variables. Results: In group i individuals a good correlation between METs estimated with the table and those obtained through gas-exchange analysis (CCI: 0.93) was observed. However, the best adjusted formula to estimate METs in group ii subjects included watts, body mass index (BMI), age and gender (METS = 11.820 − 0.054 × age − 0.189 × BMI + 1.031 × gender + 0.020 × watts) (women: 0, men: 1). This formula allowed the reclassification of 46.9% of group ii subjects into the category < 5 METs versus the estimation by table. Conclusions: Estimating the METs with the conventional table is reliable. However, the best adjustment in subjects with normal bicycle exercise SPECT was obtained when, in addition to watts and BMI, age and gender were also considered (AU)