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A 46-year-old man was admitted with non-ST elevation myocardial infarction and newly diagnosed acutely decompensated heart failure. Echocardiogram demonstrated left ventricular ejection fraction of 30% with basal inferior and inferolateral akinesis. Coronary angiography showed mild diffuse coronary artery disease and an anomalous right coronary artery arising from the left coronary cusp. Further imaging was consistent with ischemia in the right coronary distribution. Etiology of ischemia was thought to be the anomalous right coronary artery, and surgical unroofing of the right coronary ostium was performed. Here, we report a multimodality imaging approach, including cardiac magnetic resonance, cardiac computed tomographic angiography, and single-photon emission computed tomography, to support the diagnosis and management of a patient with anomalous right coronary artery arising from the left coronary cusp.
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PURPOSE: Dual-energy (DE) x-ray imaging has many clinical applications in radiography, fluoroscopy, and CT. This work characterizes a prototype dual-layer (DL) flat-panel detector (FPD) and investigates its DE imaging capabilities for applications in two-dimensional (2D) radiography/fluoroscopy and quantitative three-dimensional (3D) cone-beam CT. Unlike other DE methods like kV switching, a DL FPD obtains DE images from a single exposure, making it robust against patient and system motion. METHODS: The DL FPD consists of a top layer with a 200 µm-thick CsI scintillator coupled to an amorphous silicon (aSi) FPD of 150 µm pixel size and a bottom layer with a 550 µm thick CsI scintillator coupled to an identical aSi FPD. The two layers are separated by a 1-mm Cu filter to increase spectral separation. Images (43 × 43 cm2 active area) can be readout in 2 × 2 binning mode (300 µm pixels) at up to 15 frames per second. Detector performance was first characterized by measuring the MTF, NPS, and DQE for the top and bottom layers. For 2D applications, a qualitative study was conducted using an anthropomorphic thorax phantom containing a porcine heart with barium-filled coronary arteries (similar to iodine). Additionally, fluoroscopic lung tumor tracking was investigated by superimposing a moving tumor phantom on the thorax phantom. Tracking accuracies of single-energy (SE) and DE fluoroscopy were compared against the ground truth motion of the tumor. For 3D quantitative imaging, a phantom containing water, iodine, and calcium inserts was used to evaluate overall DE material decomposition capabilities. Virtual monoenergetic (VM) images ranging from 40 to 100 keV were generated, and the optimal VM image energy which achieved the highest image uniformity and maximum contrast-to-noise ratio (CNR) was determined. RESULTS: The spatial resolution of the top layer was substantially higher than that of the bottom layer (top layer 50% MTF = 2.2 mm-1 , bottom layer = 1.2 mm-1 ). A substantial increase in NNPS and reduction in DQE were observed for the bottom layer mainly due to photon loss within the top layer and Cu filter. For 2D radiographic and fluoroscopic applications, the DL FPD was capable of generating high-quality material-specific images separating soft tissue from bone and barium. For lung tumor tracking, DE fluoroscopy yielded more accurate results than SE fluoroscopy, with an average reduction in the root mean square error (RMSE) of over 10×. For the DE-CBCT studies, accurate basis material decompositions were obtained. The estimated material densities were 294.68 ± 17.41 and 92.14 ± 15.61 mg/ml for the 300 and 100 mg/ml calcium inserts, respectively, and 8.93 ± 1.45, 4.72 ± 1.44, and 2.11 ± 1.32 mg/ml for the 10, 5, and 2 mg/ml iodine inserts, respectively, with an average error of less than 5%. The optimal VM image energy was found to be 60 keV. CONCLUSIONS: We characterized a prototype DL FPD and demonstrated its ability to perform accurate single-exposure DE radiography/fluoroscopy and DE-CBCT. The merits of the DL detector approach include superior spatial and temporal registration between its constituent images, and less complicated acquisition sequences.
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Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional , Animales , Fluoroscopía , Humanos , Fantasmas de Imagen , Radiografía , PorcinosRESUMEN
Cone-beam CT (CBCT) is widely used in diagnostic imaging and image-guided procedures, leading to an increasing need for advanced CBCT techniques, such as dual energy (DE) imaging. Previous studies have shown that DE-CBCT can perform quantitative material decomposition, including quantification of contrast agents, electron density, and virtual monoenergetic images. Currently, most CBCT systems perform DE imaging using a kVp switching technique. However, the disadvantages of this method are spatial and temporal misregistration as well as total scan time increase, leading to errors in the material decomposition. DE-CBCT with a dual layer flat panel detector potentially overcomes these limitations by acquiring the dual energy images simultaneously. In this work, we investigate the DE imaging performance of a prototype dual layer detector by evaluating its material decomposition capability and comparing its performance to that of the kVp switching method. Two sets of x-ray spectra were used for kVp switching: 80/120 kVp and 80/120 kVp + 1 mm Cu filtration. Our results show the dual layer detector outperforms kVp switching at 80/120 kVp with matched dose. The performance of kVp switching was better by adding 1 mm copper filtration to the high energy images (80/120 kVp + 1 mm Cu), though the dual layer detector still provided comparable performance for material decomposition tasks. Overall, both the dual layer detector and kVp switching methods provided quantitative material decomposition images in DE-CBCT, with the dual layer detector having additional potential advantages.
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Echocardiography is the foundation for diagnostic cardiac testing, allowing for direct identification and management of various conditions. Point-of-care ultrasound (POCUS) has emerged as an invaluable tool for bedside diagnosis and management. The objective of this review is to address the current use and clinical applicability of POCUS to identify, triage, and manage a wide spectrum of cardiac conditions. POCUS can change diagnosis and management decisions of various cardiovascular conditions in a range of settings. In the outpatient setting, it is used to risk stratify and diagnose a variety of medical conditions. In the emergency department (ED) and critical care settings, it is used to guide triage and critical care interventions. Furthermore, the skills needed to perform POCUS can be taught to noncardiologists in a way that is retained and allows identification of normal and grossly abnormal cardiac findings. Various curricula have been developed that teach residents and advanced learners how to appropriately employ point-of-care ultrasound. In conclusion, POCUS can be a useful adjunct to the physical exam, particularly in critical care applications.
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Enfermedades Cardiovasculares/diagnóstico por imagen , Ecocardiografía/métodos , Sistemas de Atención de Punto , Humanos , Medición de Riesgo , TriajeRESUMEN
The development and psychometric qualities of a measure using teacher judgment to rate performance in reading comprehension for narrative text is described-the Rating Scales for Academic Skills-Reading Comprehension Narrative (RSAS-RCN). Sixty-five teachers from the third, fourth, and fifth grades of 8 elementary schools completed the measure on 177 students. Each teacher rated students who had been identified through school-based universal screening to be below the 25th percentile, between the 25th and 74th percentile, and at or above the 75th percentile on national normative standards. Results indicated the RSAS-RCN has strong to moderate evidence of (a) 1-week test-retest reliability, (b) concurrent validity with the Group Reading Assessment and Diagnostic Evaluation (GRADE) and end of year state assessment in reading, and (c) significant classification accuracy across student ability levels. Principal component analysis and item response theory (Rasch modeling) indicate the RSAS-RCN is comprised of a single general dimension. Overall, this examination of the RSAS-RCN suggests teacher judgment may be a potentially valuable tool in assessing reading comprehension among upper elementary school students. (PsycINFO Database Record
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Comprensión , Evaluación Educacional/métodos , Lectura , Estudiantes/psicología , Niño , Femenino , Humanos , Masculino , Psicometría , Instituciones AcadémicasRESUMEN
The purpose of the study was to compare the use of a Computer Adaptive Test and Curriculum-Based Measurement in the assessment of mathematics. This study also investigated the degree to which slope or rate of change predicted student outcomes on the annual state assessment of mathematics above and beyond scores of single point screening assessments (i.e., the computer adaptive test or the CBM assessment just before the administration of the state assessment). Repeated measurement of mathematics once per month across a 7-month period using a Computer Adaptive Test (STAR-Math) and Curriculum-Based Measurement (CBM, AIMSweb Math Computation, AIMSweb Math Concepts/Applications) was collected for a maximum total of 250 third, fourth, and fifth grade students. Results showed STAR-Math in all 3 grades and AIMSweb Math Concepts/Applications in the third and fifth grades had primarily linear growth patterns in mathematics. AIMSweb Math Computation in all grades and AIMSweb Math Concepts/Applications in Grade 4 had decelerating positive trends. Predictive validity evidence showed the strongest relationships were between STAR-Math and outcomes for third and fourth grade students. The blockwise multiple regression by grade revealed that slopes accounted for only a very small proportion of additional variance above and beyond what was explained by the scores obtained on a single point of assessment just prior to the administration of the state assessment.
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Curriculum , Evaluación Educacional/métodos , Matemática , Estudiantes , Niño , Femenino , Humanos , Masculino , Proyectos de InvestigaciónRESUMEN
BACKGROUND: Multi-detector computed tomography angiography (MDCTA) is a promising method for risk assessment of patients with acute chest pain. However, its diagnostic performance in higher-risk patients has not been investigated in a large international multicenter trial. Therefore, in the present study we sought to estimate the diagnostic accuracy of MDCTA to detect significant coronary stenosis in patients with acute coronary syndrome (ACS). METHODS: Patients included in the CORE64 study were categorized as suspected-ACS or non-ACS based on clinical data. A 64-row coronary MDCTA was performed before invasive coronary angiography (ICA) and both exams were evaluated by blinded, independent core laboratories. RESULTS: From 371 patients included, 94 were categorized as suspected ACS and 277 as non-ACS. Patient-based analysis showed an area under the receiver-operating-characteristic curve (AUC) for detecting ≥ 50% coronary stenosis of 0.95 (95% CI: 0.88-0.98) in ACS and 0.92 (95% CI: 0.88-0.95) in non-ACS group (P=0.29). The sensitivity, specificity, positive and negative predictive values of MDCTA were 0.90(0.80-0.96), 0.88(0.70-0.98), 0.95(0.87-0.99) and 0.77(0.58-0.90) in suspected ACS patients and 0.87(0.81-0.92), 0.86(0.79-0.92), 0.91(0.85-0.95) and 0.82(0.74-0.89) in non-ACS patients (P NS for all comparisons). The mean calcium scores (CS) were 282 ± 449 in suspected ACS and 435 ± 668 in non-ACS group. The accuracy of CS to detect significant coronary stenosis was only moderate and the absence or minimal coronary artery calcification could not exclude the presence of significant coronary stenosis, particularly in ACS patients. CONCLUSIONS: The diagnostic accuracy of MDCTA to detect significant coronary stenosis is high and comparable for both ACS and non-ACS patients.
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Síndrome Coronario Agudo/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Internacionalidad , Tomografía Computarizada Multidetector/normas , Síndrome Coronario Agudo/epidemiología , Anciano , Enfermedad de la Arteria Coronaria/epidemiología , Estenosis Coronaria/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
This study compared the validity of progress monitoring slope of nonsense word fluency (NWF) and word identification fluency (WIF) with early first-grade readers. Students (N = 80) considered to be at risk for reading difficulty were monitored with NWF and WIF on a 1-2 week basis across 11 weeks. Reading skills at the end of first grade were assessed using measures of passage reading fluency, real and pseudoword reading efficiency, and basic comprehension. Latent growth models indicated that although slope on both measures significantly predicted year-end reading skills, models including WIF accounted for more variance in spring reading skills than NWF, and WIF slope was more strongly associated with reading outcomes than NWF slope. Analyses of student growth plots suggested that WIF slope was more positively associated with later reading skills and discriminated more clearly between students according to successful or unsuccessful year-end reading outcomes. Although both measures may be used to monitor reading growth of at-risk students in early first grade, WIF may provide a clearer index of reading growth. Implications for data-based decision-making are discussed.
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Comprensión/fisiología , Evaluación Educacional/estadística & datos numéricos , Lectura , Niño , Evaluación Educacional/normas , Femenino , Humanos , Masculino , Modelos Psicológicos , Estudiantes/estadística & datos numéricosRESUMEN
Atrial septal defect (ASD) is a common congenital abnormality that occurs in the form of ostium secundum, ostium primum, sinus venosus, and rarely, coronary sinus defects. Pathophysiologic consequences of ASDs typically begin in adulthood, and include arrhythmia, paradoxical embolism, cerebral abscess, pulmonary hypertension, and right ventricular failure. Two-dimensional (2D) transthoracic echocardiography with Doppler is a central aspect of the evaluation. This noninvasive imaging modality often establishes the diagnosis and provides critical information guiding intervention. A comprehensive echocardiogram includes evaluation of anatomical ASD characteristics, flow direction, associated abnormalities (eg, anomalous pulmonary veins), right ventricular anatomy and function, pulmonary pressures, and the pulmonary/systemic flow ratio. The primary indication for ASD closure is right heart volume overload, whether symptoms are present or not. ASD closure may also be reasonable in other contexts, such as paradoxical embolism. ASD type and local clinical expertise guide choice of a percutaneous versus surgical approach to ASD closure.
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To investigate the patterns and diagnostic implications of coronary arterial lesion calcification by CT angiography (CTA) using a novel, cross-sectional grading method, we studied 371 patients enrolled in the CorE-64 study who underwent CTA and invasive angiography for detecting coronary artery stenoses by quantitative coronary angiography (QCA). The number of quadrants involving calcium on a cross-sectional view for ≥ 30 and ≥ 50 % lesions in 4,511 arterial segments was assessed by CTA according to: noncalcified, mild (one-quadrant), moderate (two-quadrant), severe (three-quadrant) and very severe (four-quadrant calcium). Area under the receiver operating characteristic curve (AUC) were used to evaluate CTA diagnostic accuracy and agreement versus. QCA for plaque types. Only 4 % of ≥ 50 % stenoses by QCA were very severely calcified while 43 % were noncalcified. AUC for CTA to detect ≥ 50 % stenoses by QCA for non-calcified, mildly, moderately, severely, and very severely calcified plaques were 0.90, 0.88, 0.83, 0.76 and 0.89, respectively (P < 0.05). In 198 lesions with severe calcification, the presence or absence of a visible residual lumen by CTA was associated with ≥ 50 % stenosis by QCA in 20.3 and 76.9 %, respectively. Kappa was 0.93 for interobserver variability in evaluating plaque calcification. We conclude that calcification of individual coronary artery lesions can be reliably graded using CTA. Most ≥ 50 % coronary artery stenoses are not or only mildly calcified. If no residual lumen is seen on CTA, calcified lesions are predictive of ≥ 50 % stenoses and vice versa. CTA diagnostic accuracy for detecting ≥ 50 % stenoses is reduced in lesions with more than mild calcification due to lower specificity.
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Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Tomografía Computarizada Multidetector , Calcificación Vascular/diagnóstico por imagen , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Índice de Severidad de la EnfermedadRESUMEN
The APA Division 16 Working Group on Translating Science to Practice contends that implementation science is essential to the process of translating evidence-based interventions (EBIs) into the unique context of the schools, and that increasing attention to implementation will lead to the improvement of school psychological services and school learning environments. Key elements of implementation and implementation science are described. Four critical issues for implementation science in school psychology are presented: barriers to implementation, improving intervention fidelity and identifying core intervention components, implementation with diverse client populations, and implementation in diverse settings. What is known and what researchers need to investigate for each set of issues is addressed. A discussion of implementation science methods and measures is included. Finally, implications for research, training and practice are presented.
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Difusión de Innovaciones , Innovación Organizacional , Instituciones Académicas/organización & administración , Estudiantes/psicología , Práctica Clínica Basada en la Evidencia , Humanos , Modelos Teóricos , Investigación Biomédica TraslacionalAsunto(s)
Curriculum , Evaluación Educacional/métodos , Lectura , Instituciones Académicas , Estudiantes , HumanosRESUMEN
PURPOSE: Detector lag, or residual signal, in a-Si flat-panel (FP) detectors can cause significant shading artifacts in cone-beam computed tomography reconstructions. To date, most correction models have assumed a linear, time-invariant (LTI) model and correct lag by deconvolution with an impulse response function (IRF). However, the lag correction is sensitive to both the exposure intensity and the technique used for determining the IRF. Even when the LTI correction that produces the minimum error is found, residual artifact remains. A new non-LTI method was developed to take into account the IRF measurement technique and exposure dependencies. METHODS: First, a multiexponential (N = 4) LTI model was implemented for lag correction. Next, a non-LTI lag correction, known as the nonlinear consistent stored charge (NLCSC) method, was developed based on the LTI multiexponential method. It differs from other nonlinear lag correction algorithms in that it maintains a consistent estimate of the amount of charge stored in the FP and it does not require intimate knowledge of the semiconductor parameters specific to the FP. For the NLCSC method, all coefficients of the IRF are functions of exposure intensity. Another nonlinear lag correction method that only used an intensity weighting of the IRF was also compared. The correction algorithms were applied to step-response projection data and CT acquisitions of a large pelvic phantom and an acrylic head phantom. The authors collected rising and falling edge step-response data on a Varian 4030CB a-Si FP detector operating in dynamic gain mode at 15 fps at nine incident exposures (2.0%-92% of the detector saturation exposure). For projection data, 1st and 50th frame lag were measured before and after correction. For the CT reconstructions, five pairs of ROIs were defined and the maximum and mean signal differences within a pair were calculated for the different exposures and step-response edge techniques. RESULTS: The LTI corrections left residual 1st and 50th frame lag up to 1.4% and 0.48%, while the NLCSC lag correction reduced 1st and 50th frame residual lags to less than 0.29% and 0.0052%. For CT reconstructions, the NLCSC lag correction gave an average error of 11 HU for the pelvic phantom and 3 HU for the head phantom, compared to 14-19 HU and 2-11 HU for the LTI corrections and 15 HU and 9 HU for the intensity weighted non-LTI algorithm. The maximum ROI error was always smallest for the NLCSC correction. The NLCSC correction was also superior to the intensity weighting algorithm. CONCLUSIONS: The NLCSC lag algorithm corrected for the exposure dependence of lag, provided superior image improvement for the pelvic phantom reconstruction, and gave similar results to the best case LTI results for the head phantom. The blurred ring artifact that is left over in the LTI corrections was better removed by the NLCSC correction in all cases.
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Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Dinámicas no Lineales , Silicio , CalibraciónRESUMEN
BACKGROUND: Increased blood pressure (BP) in type 2 diabetes (T2DM) markedly increases cardiovascular disease morbidity and mortality risk compared to having increased BP alone. OBJECTIVE: To investigate whether exercise reduces suboptimal levels of untreated suboptimal BP or treated hypertension. DESIGN: Prospective, randomized controlled trial for 6 months. SETTING: Single center in Baltimore, MD, USA. PATIENTS: 140 participants with T2DM not requiring insulin and untreated SBP of 120-159 or DBP of 85-99 mmHg, or, if being treated for hypertension, any SBP <159 mmHg or DBP<99 mmHg; 114 completed the study. INTERVENTION: Supervised exercise, 3 times per week for 6 months compared with general advice about physical activity. MEASUREMENTS: Resting SBP and DBP (primary outcome); diabetes status, arterial stiffness assessed as carotid-femoral pulse-wave velocity (PWV), body composition and fitness (secondary outcomes). RESULTS: Overall baseline BP was 126.8 ± 13.5 / 71.7 ± 9.0 mmHg, with no group differences. At 6 months, BP was unchanged from baseline in either group, BP 125.8 ± 13.2 / 70.7 ± 8.8 mmHg in controls; and 126.0 ± 14.2 / 70.3 ± 9.0 mmHg in exercisers, despite attaining a training effects as evidenced by increased aerobic and strength fitness and lean mass and reduced fat mass (all p<0.05), Overall baseline PWV was 959.9 ± 333.1 cm/s, with no group difference. At 6-months, PWV did not change and was not different between group; exercisers, 923.7 ± 319.8 cm/s, 905.5 ± 344.7, controls. LIMITATIONS: A completion rate of 81 %. CONCLUSIONS: Though exercisers improve fitness and body composition, there were no reductions in BP. The lack of change in arterial stiffness suggests a resistance to exercise-induced BP reduction in persons with T2DM.
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Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Ejercicio Físico/fisiología , Hipertensión/terapia , Adulto , Anciano , Femenino , Humanos , Hipertensión/etiología , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
It is possible to teach residents to listen psychodynamically within pressured clinical systems that are organized around brief management interventions without changing the structure of the training program to create "selected psychotherapy cases." Two case vignettes illustrate the amount of psychodynamic data that can be elicited from a time-limited clinical assessment. Focusing on the psychodynamics of social systems and the subtle ways in which patients and clinicians become involved with each other during assessment meetings can allow trainees to grasp unconscious functioning, projective identification, transference/countertransference, and interpretation. This perspective opens a way of thinking that illuminates the patient's struggles, reduces the need for management by helping the patient take charge of his or her treatment, and opens possibilities for both patient and trainee to improve their capacity to listen, both to themselves and to the human systems that surround them.
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Internado y Residencia , Relaciones Médico-Paciente , Psiquiatría/educación , Psicoterapia/educación , HumanosRESUMEN
OBJECTIVES: The purpose of this study was to assess the impact of patient population characteristics on accuracy by computed tomography angiography (CTA) to detect obstructive coronary artery disease (CAD). BACKGROUND: The ability of CTA to exclude obstructive CAD in patients of different pre-test probabilities and in presence of coronary calcification remains uncertain. METHODS: For the CORE-64 (Coronary Artery Evaluation Using 64-Row Multidetector Computed Tomography Angiography) study, 371 patients underwent CTA and cardiac catheterization for the detection of obstructive CAD, defined as ≥50% luminal stenosis by quantitative coronary angiography (QCA). This analysis includes 80 initially excluded patients with a calcium score ≥600. Area under the receiver-operating characteristic curve (AUC) was used to evaluate CTA diagnostic accuracy compared to QCA in patients according to calcium score and pre-test probability of CAD. RESULTS: Analysis of patient-based quantitative CTA accuracy revealed an AUC of 0.93 (95% confidence interval [CI]: 0.90 to 0.95). The AUC remained 0.93 (95% CI: 0.90 to 0.96) after excluding patients with known CAD but decreased to 0.81 (95% CI: 0.71 to 0.89) in patients with calcium score ≥600 (p = 0.077). While AUCs were similar (0.93, 0.92, and 0.93, respectively) for patients with intermediate, high pre-test probability for CAD, and known CAD, negative predictive values were different: 0.90, 0.83, and 0.50, respectively. Negative predictive values decreased from 0.93 to 0.75 for patients with calcium score <100 or ≥100, respectively (p = 0.053). CONCLUSIONS: Both pre-test probability for CAD and coronary calcium scoring should be considered before using CTA for excluding obstructive CAD. For that purpose, CTA is less effective in patients with calcium score ≥600 and in patients with a high pre-test probability for obstructive CAD.