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Background Activation of brown adipose tissue (BAT) in rodents increases lipolysis in white adipose tissue (WAT) and improves glucose tolerance. Adult humans can have metabolically active BAT. Implications for diabetes and obesity in humans require a better characterization of BAT in humans. Purpose To study fat depots with localized proton MR spectroscopy relaxometry and to identify differences between WAT and fluorine 18 fluorodeoxyglucose (FDG) PET/CT proven cold-activated BAT in humans. Materials and Methods Participants were consecutively enrolled in this prospective study (ClinicalTrials.gov identifiers: NCT01568671 and NCT01399385) from August 2016 to May 2019. Supraclavicular potential BAT regions were localized with MRI. Proton densities, T1, and T2 were measured with localized MR spectroscopy in potential BAT and in subcutaneous WAT. FDG PET/CT after cold stimulation was used to retrospectively identify active supraclavicular BAT or supraclavicular quiescent adipose tissue (QAT) regions. MR spectroscopy results from BAT and WAT were compared with grouped and paired tests. Results Of 21 healthy participants (mean age, 36 years ± 16 [standard deviation]; 13 men) FDG PET/CT showed active BAT in 24 MR spectroscopy-targeted regions in 16 participants (eight men). Four men had QAT. The T2 for methylene protons was shorter in BAT (mean, 69 msec ± 6, 24 regions) than in WAT (mean, 83 msec ± 3, 18 regions, P < .01) and QAT (mean, 78 msec ± 2, five regions, P < .01). A T2 cut-off value of 76 msec enabled the differentiation of BAT from WAT or QAT with a sensitivity of 85% and a specificity of 95%. Densities of protons adjacent and between double bonds were 33% and 24% lower, respectively, in BAT compared with those in WAT (P = .01 and P = .03, respectively), indicating a lower content of unsaturated and polyunsaturated fatty acids, respectively, in BAT compared with WAT. Conclusion Proton MR spectroscopy showed shorter T2 and lower unsaturated fatty acids in brown adipose tissue (BAT) than that in white adipose tissue in healthy humans. It was feasible to identify BAT with MR spectroscopy without the use of PET/CT or cold stimulation. © RSNA, 2021 See also the editorial by Barker in this issue. Online supplemental material is available for this article.
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Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Branco/diagnóstico por imagem , Ácidos Graxos Insaturados/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Compostos Radiofarmacêuticos , Sensibilidade e EspecificidadeRESUMO
Purpose To assess early subclinical coronary artery disease (CAD) burden and its relation to myocardial function in asymptomatic persons living with HIV (PLWH) who are at low risk for cardiovascular disease (CVD). Materials and Methods In this prospective, HIPAA-compliant study (ClinicalTrials.gov NCT01656564 and NCT01399385) conducted from April 2010 to May 2013, 74 adult PLWH without known CVD and 25 matched healthy controls underwent coronary MRI to measure coronary vessel wall thickness (VWT) and echocardiography to assess left ventricular function. Univariable and multivariable linear regression analyses were used to evaluate statistical associations. Results For PLWH, the mean age was 49 years ± 11 (SD), and the median Framingham risk score was 3.2 (IQR, 0.5-6.6); for matched healthy controls, the mean age was 46 years ± 8 and Framingham risk score was 2.3 (IQR, 0.6-6.1). PLWH demonstrated significantly greater coronary artery VWT than did controls (1.47 mm ± 0.22 vs 1.34 mm ± 0.18; P = .006) and a higher left ventricular mass index (LVMI) (77 ± 16 vs 70 ± 13; P = .04). Compared with controls, PLWH showed altered association between coronary artery VWT and both E/A (ratio of left ventricular-filling peak blood flow velocity in early diastole [E wave] to that in late diastole [A wave]) (P = .03) and LVMI (P = .04). In the PLWH subgroup analysis, coronary artery VWT increase was associated with lower E/A (P < .001) and higher LVMI (P = .03), indicating restricted diastolic function. In addition, didanosine exposure was associated with increased coronary artery VWT and decreased E/A ratio. Conclusion Asymptomatic low-CVD-risk PLWH demonstrated increased coronary artery VWT in association with impaired diastolic function, which may be amenable to follow-up studies of coronary pathogenesis to identify potential effects on the myocardium and risk modification strategies. Keywords: Coronary Vessel Wall Thickness, Diastolic Function, HIV, MRI, Echocardiography, Atherosclerosis Clinical trial registration nos. NCT01656564 and NCT01399385 Supplemental material is available for this article. © RSNA, 2024.
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Doenças Cardiovasculares , Infecções por HIV , Adulto , Humanos , Pessoa de Meia-Idade , Diástole , Coração , Infecções por HIV/complicações , Estudos ProspectivosRESUMO
Aneurysms presented with mass effect are traditionally treated by surgical clipping to decompress their mass effect. The aim of this work is to discuss the efficiency of endovascular techniques in treating 47 patients with variable sizes of intracranial aneurysms presented with mass effect and/or cranial nerve palsy. There were 47 patients with 47 unruptured aneurysms. Group I includes 28 giant aneurysms; all are treated by parent vessel occlusion with or without intra-aneurysmal occlusion depending on anatomical locations. Group II includes 19 small and large aneurysms; all are treated by selective endosaccular occlusion with coils. Clinical presentations were ocular cranial nerve dysfunction (82.9%), optic nerve or chiasmatic dysfunction (21.2%), brain stem compression (8.5%), embolic (6%), epistaksis (4%), proptosis (2%), and bleeding per ear (2%). Out of 47 patients, symptoms were resolved in 31 cases (66%), improved in 10 cases (21%), and unchanged in six cases (13%). Out of 28 giant aneurysms, symptoms were resolved in 19 (68%), improved in four (14%), and unchanged in five (18%). Only four (14%) patients out of the 19 giant aneurysms with complete symptoms resolution showed significant mass reduction in MRI. Out of 19 non-giant aneurysm cases treated by selective endovascular occlusion with coils, symptoms were resolved in 12 cases (63%), improved in six (32%), and unchanged in one (5%). No complications from the treatment were observed. The longer the duration of symptoms before endovascular treatment is, the longer the duration till improvement or resolution postoperative in both groups. Recovery of aneurysm-induced mass effect occurs in most patients both after parent vessel occlusion and after selective coiling, and is comparable to results after surgical clipping. The improvement starts independent of aneurysmal shrinkage in postoperative MRI follow-ups. The arrest of pulsations and partial shrinkage within the aneurysms after endovascular treatment may be the logical reason behind neurological recovery.
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Doenças dos Nervos Cranianos/etiologia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , Oftalmoplegia/etiologia , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Paralisia/etiologia , Recuperação de Função Fisiológica , Resultado do TratamentoRESUMO
Coronary artery disease (CAD) risk and plaque scores are often subjective and biased, particularly in mid-age asymptomatic women, whose CAD risk assessment has been historically underestimated. In this study, a new automatic ascending aorta time-to-peak-distention (TPD) analysis was developed for fast screening and as an independent surrogate for subclinical atherosclerosis in asymptomatic women. CCTA was obtained in 50 asymptomatic adults. Plaque burden segment involvement score (SIS) and automatic TPD were obtained from all subjects. Logistic regression analyses were performed to investigate the association between CAD risk scores and TPD with severe coronary plaque burden (SIS>5). TPD, individually, was found to be a significant predictor of SIS>5. Additionally, sex was a significant effect modifier of TPD, with a stronger statistically significant association with women. Four-dimensional aortic time-to-peak distention could supplement conventional CCTA analysis and offer a quick objective screening tool for plaque burden severity and CAD risk stratification, especially in women.
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BACKGROUND: Assessment of regional myocardial function at native pixel-level resolution can play a crucial role in recognizing the early signs of the decline in regional myocardial function. Extensive data processing in existing techniques limits the effective resolution and accuracy of the generated strain maps. The purpose of this study is to compute myocardial principal strain maps εp1 and εp2 from tagged MRI (tMRI) at the native image resolution using deep-learning local patch convolutional neural network (CNN) models (DeepStrain). METHODS: For network training, validation, and testing, realistic tMRI datasets were generated and consisted of 53,606 cine images simulating the heart, the liver, blood pool, and backgrounds, including ranges of shapes, positions, motion patterns, noise, and strain. In addition, 102 in-vivo image datasets from three healthy subjects, and three Pulmonary Arterial Hypertension patients, were acquired and used to assess the network's in-vivo performance. Four convolutional neural networks were trained for mapping input tagging patterns to corresponding ground-truth principal strains using different cost functions. Strain maps using harmonic phase analysis (HARP) were obtained with various spectral filtering settings for comparison. CNN and HARP strain maps were compared at the pixel level versus the ground-truth and versus the least-loss in-vivo maps using Pearson correlation coefficients (R) and the median error and Inter-Quartile Range (IQR) histograms. RESULTS: CNN-based local patch DeepStrain maps at a phantom resolution of 1.1mm × 1.1 mm and in-vivo resolution of 2.1mm × 1.6 mm were artifact-free with multiple fold improvement with εp1 ground-truth median error of 0.009(0.007) vs. 0.32(0.385) using HARP and εp2 ground-truth error of 0.016(0.021) vs. 0.181(0.08) using HARP. CNN-based strain maps showed substantially higher agreement with the ground-truth maps with correlation coefficients R > 0.91 for εp1 and εp2 compared to R < 0.21 and R < 0.82 for HARP-generated maps, respectively. CONCLUSION: CNN-generated Eulerian strain mapping permits artifact-free visualization of myocardial function at the native image resolution.
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Imageamento por Ressonância Magnética , Redes Neurais de Computação , Coração/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Imagens de FantasmasRESUMO
Regional soft tissue mechanical strain offers crucial insights into tissue's mechanical function and vital indicators for different related disorders. Tagging magnetic resonance imaging (tMRI) has been the standard method for assessing the mechanical characteristics of organs such as the heart, the liver, and the brain. However, constructing accurate artifact-free pixelwise strain maps at the native resolution of the tagged images has for decades been a challenging unsolved task. In this work, we developed an end-to-end deep-learning framework for pixel-to-pixel mapping of the two-dimensional Eulerian principal strains [Formula: see text] and [Formula: see text] directly from 1-1 spatial modulation of magnetization (SPAMM) tMRI at native image resolution using convolutional neural network (CNN). Four different deep learning conditional generative adversarial network (cGAN) approaches were examined. Validations were performed using Monte Carlo computational model simulations, and in-vivo datasets, and compared to the harmonic phase (HARP) method, a conventional and validated method for tMRI analysis, with six different filter settings. Principal strain maps of Monte Carlo tMRI simulations with various anatomical, functional, and imaging parameters demonstrate artifact-free solid agreements with the corresponding ground-truth maps. Correlations with the ground-truth strain maps were R = 0.90 and 0.92 for the best-proposed cGAN approach compared to R = 0.12 and 0.73 for the best HARP method for [Formula: see text] and [Formula: see text], respectively. The proposed cGAN approach's error was substantially lower than the error in the best HARP method at all strain ranges. In-vivo results are presented for both healthy subjects and patients with cardiac conditions (Pulmonary Hypertension). Strain maps, obtained directly from their corresponding tagged MR images, depict for the first time anatomical, functional, and temporal details at pixelwise native high resolution with unprecedented clarity. This work demonstrates the feasibility of using the deep learning cGAN for direct myocardial and liver Eulerian strain mapping from tMRI at native image resolution with minimal artifacts.
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Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Fígado/diagnóstico por imagem , Método de Monte Carlo , Estresse MecânicoRESUMO
CONTEXT: Radiological characterization of adrenal size in primary bilateral macronodular adrenocortical hyperplasia (PBMAH) has not been previously investigated. OBJECTIVE: We hypothesized that volumetric modeling of adrenal gland size may correlate with biochemical disease severity in patients with PBMAH. Secondary analysis of patients with concurrent primary aldosteronism (PA) was performed. DESIGN: A retrospective cross-sectional analysis of 44 patients with PBMAH was conducted from 2000 to 2019. SETTING: Tertiary care clinical research center. PATIENTS: Patients were diagnosed with PBMAH based upon clinical, genetic, radiographic and biochemical characteristics. INTERVENTION: Clinical, biochemical, and genetic data were obtained. Computed tomography scans were used to create volumetric models by manually contouring both adrenal glands in each slice using Vitrea Core Fx v6.3 software (Vital Images, Minnetonka, Minnesota). MAIN OUTCOME AND MEASURES: 17-hydroxycorticosteroids (17-OHS), ARMC5 genetics, and aldosterone-to-renin ratio (ARR) were retrospectively obtained. Pearson test was used for correlation analysis of biochemical data with adrenal volume. RESULTS: A cohort of 44 patients with PBMAH was evaluated, with a mean age (±SD) of 53â ±â 11.53. Eight patients met the diagnostic criteria for PA, of whom 6 (75%) were Black. In the Black cohort, total adrenal volumes positively correlated with midnight cortisol (Râ =â 0.76, Pâ =â 0.028), urinary free cortisol (Râ =â 0.70, Pâ =â 0.035), and 17-OHS (Râ =â 0.87, Pâ =â 0.0045), with a more pronounced correlation with left adrenal volume alone. 17-OHS concentration positively correlated with total, left, and right adrenal volume in patients harboring pathogenic variants in ARMC5 (Râ =â 0.72, Pâ =â 0.018; Râ =â 0.65, Pâ =â 0.042; and Râ =â 0.73, Pâ =â 0.016, respectively). CONCLUSIONS: Volumetric modeling of adrenal gland size may associate with biochemical severity in patients with PBMAH, with particular utility in Black patients.
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This study aimed to evaluate liver involvement in patients with Carney complex (CNC) based on a large cohort and to analyze any germline PRKAR1A genotype-phenotype association of liver disease. The study included 83 patients with CNC, followed between 1995 and 2018 at a tertiary research center. We reviewed liver images, recorded types and number of lesions and analyzed per genotype: all patients were sequenced for the PRKAR1A gene. A total of 29/83 patients (24.0%) had liver radiological findings. Patients with liver lesion had a significantly higher rate of pathogenic variants detected in the PRKAR1A gene (72.4 vs 38.9%, P = 0.005, respectively). Patients with a pathogenic variant detected on germline PRKAR1A analysis had a higher risk for having a liver lesion compared with patients with wild-type (WT) PRKAR1A alleles (21/42 (50.0%) vs 8/41 (19.5%), respectively, P = 0.004). Among patients with liver lesions, those with a nonsense PRKAR1A pathogenic-variant had more liver lesions (7/7) than among those with other pathogenic-variant types (8/22, P = 0.001). In multivariable analysis, detection of liver lesion(s) was associated with an odds ratio of 5.2 for cardiac myxomas (95% CI 1.55-17.49, P = 0.008). In conclusion, patients with CNC, particularly with a PRKAR1A pathogenic variant, have a higher rate of liver lesions. Additionally, liver lesions are associated with a high risk for cardiac myxomas in this population.
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Complexo de Carney/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Neoplasias Cardíacas/genética , Mixoma/genética , Adulto , Feminino , Genótipo , Células Germinativas , Neoplasias Cardíacas/patologia , Humanos , Fígado/patologia , Masculino , Mixoma/patologia , Fenótipo , Estudos RetrospectivosRESUMO
CONTEXT: Pheochromocytomas/paragangliomas (PPGLs) are neuroendocrine tumors that can secrete norepinephrine (NE). Brown adipose tissue (BAT) activation is mediated through the action of NE on ß-adrenoceptors (ß-ARs). In some malignancies, BAT activation is associated with higher cancer activity. OBJECTIVE: To study the relationship between BAT activation and PPGL clinical outcomes. DESIGN: A retrospective case-control study that included 342 patients with PPGLs who underwent 18F-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (18F-FDG PET/CT) imaging at the National Institutes of Health (NIH). We excluded all patients with parasympathetic tumors and those who underwent 18F-FDG PET/CT after PPGL resection. Scans of 205 patients were reviewed by 2 blinded nuclear medicine physicians; 16 patients had BAT activation on 18F-FDG PET/CT [7.80%; age 27.50 (15.00-45.50) years; 10 female/6 male; body mass index [BMI] 24.90 [19.60-25.35] kg/m2). From the remaining 189 patients, we selected 36 matched controls (age 34.4 [25.4-45.5] years; 21 female/15 male; BMI 25.0 [22.0-26.0] kg/m2). PRIMARY OUTCOME MEASURE: Overall survival. RESULTS: The presence of active BAT on 18F-FDG PET/CT was associated with decreased overall survival when compared with the control group (HRz 5.80; 95% CI, 1.05-32.05; P = 0.02). This association remained significant after adjusting for the SDHB mutation. Median plasma NE in the BAT group was higher than the control group [4.65 vs 0.55 times above the upper limit of normal; P < 0.01]. There was a significant association between higher plasma NE levels and mortality in PPGLs in both groups. CONCLUSIONS: Our findings suggest that the detection of BAT activity in PPGL patients is associated with higher mortality. We suggest that BAT activation could either be reflecting or contributing to a state of increased host stress that may predict poor outcome in metastatic PPGL.
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Tecido Adiposo Marrom/patologia , Neoplasias das Glândulas Suprarrenais/mortalidade , Paraganglioma/mortalidade , Feocromocitoma/mortalidade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/metabolismo , Tecido Adiposo Marrom/diagnóstico por imagem , Adolescente , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Paraganglioma/diagnóstico por imagem , Paraganglioma/patologia , Feocromocitoma/diagnóstico por imagem , Feocromocitoma/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto JovemRESUMO
Measuring coronary artery distensibility can determine the arterial remodeling type, arterial wall inflammation, and atherosclerotic plaques in early stage even before any observed narrowing in the lumen. This is crucial to promote an appropriate, preventive, and effective treatment. This study introduces a framework for calculating the 3D distensibility of the left coronary artery (LCA) from time-resolved coronary computerized tomography angiography (CCTA) images. Vesselness, region growing, and level sets are utilized for segmenting the LCA lumen in the systole and diastole CCTA time frames. The segmented arteries are then analyzed and registered using computational geometry to calculate the changes in the lumen cross-section areas between both time frames. In-vivo validation of the framework performance was accomplished against that of two radiologists and their consensus. Results demonstrate that the framework was accurate and reliable tool for measuring the coronary arteries distensibility.
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Angiografia por Tomografia Computadorizada , Doença da Artéria Coronariana , Angiografia Coronária , Vasos Coronários , Humanos , Tomografia Computadorizada por Raios XRESUMO
Coronary plaque burden measured by coronary computerized tomography angiography (CCTA), independent of stenosis, is a significant independent predictor of coronary heart disease (CHD) events and mortality. Hence, it is essential to develop comprehensive CCTA plaque quantification beyond existing subjective plaque volume or stenosis scoring methods. The purpose of this study is to develop a framework for automated 3D segmentation of CCTA vessel wall and quantification of atherosclerotic plaque, independent of the amount of stenosis, along with overcoming challenges caused by poor contrast, motion artifacts, severe stenosis, and degradation of image quality. Vesselness, region growing, and two sequential level sets are employed for segmenting the inner and outer wall to prevent artifact-defective segmentation. Lumen and vessel boundaries are joined to create the coronary wall. Curved multiplanar reformation is used to straighten the segmented lumen and wall using lumen centerline. In-vivo evaluation included CCTA stenotic and non-stenotic plaques from 41 asymptomatic subjects with 122 plaques of different characteristics against the individual and consensus of expert readers. Results demonstrate that the framework segmentation performed robustly by providing a reliable working platform for accelerated, objective, and reproducible atherosclerotic plaque characterization beyond subjective assessment of stenosis; can be potentially applicable for monitoring response to therapy.
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Automação/métodos , Angiografia por Tomografia Computadorizada/métodos , Imageamento Tridimensional/métodos , Placa Aterosclerótica/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
PURPOSE: To demonstrate the association between coronary vessel wall thickness (VWT) measured at MRI and coronary artery disease (CAD) risk in asymptomatic groups at low and intermediate risk on the basis of Framingham score. MATERIALS AND METHODS: A total of 131 asymptomatic adults were prospectively enrolled. All participants underwent CT angiography for scoring CAD, and coronary VWT was measured at 3.0-T MRI. Nonlinear single and multivariable regression analyses with consideration for interaction with sex were performed to investigate the association of traditional atherosclerotic risk factors and VWT with CT angiography-based CAD scores. RESULTS: The analysis included 62 women and 62 men with low or intermediate Framingham score of less than 20%. Age (mean age, 45.0 years ± 14.5 [standard deviation]) and body mass index were not different between the groups. Age, sex, and VWT were individually significantly associated with all CT angiography-based CAD scores (P < .05). Additionally, sex was a significant effect modifier of the associations with all CAD scores. In men, age was the only statistically significant independent risk factor of CAD; in women, VWT was the only statistically significant independent surrogate associated with increased CAD scores (P < .05). CONCLUSION: In asymptomatic women, VWT MRI was the primary independent surrogate of CAD, whereas age was the strongest risk factor in men. This study suggests that VWT may be used as a CAD surrogate in women at low or intermediate risk of CAD. Further longitudinal studies are required to determine the potential implication and use of this MRI technique for the preventative management of CAD in women.© RSNA, 2019.
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BACKGROUND: Current guidelines for the primary prevention of atherosclerotic cardiovascular disease are based on the estimation of a predicted 10-year cardiovascular disease risk and the average relative risk reduction estimates from statin trials. In the clinical setting, however, decision-making is better informed by the expected benefit for the individual patient, which is typically lacking. Consequently, a personalized statin benefit approach based on absolute risk reduction over 10 years (ARR10 benefit threshold ≥2.3%) has been proposed as a novel approach. However, how this benefit threshold relates with coronary plaque burden in asymptomatic individuals with low/intermediate cardiovascular disease risk is unknown. AIMS: In this study, we compared the predicted ARR10 obtained in each individual with plaque burden detected by coronary computed tomography angiography. METHODS AND RESULTS: Plaque burden (segment volume score, segment stenosis score, and segment involvement score) was assessed in prospectively recruited asymptomatic subjects (n = 70; 52% male; median age 56 years [interquartile range 51-64 years]) with low/intermediate Framingham risk score (< 20%). The expected ARR10 with statin in the entire cohort was 2.7% (1.5-4.6%) with a corresponding number needed to treat over 10 years of 36 (22-63). In subjects with an ARR10 benefit threshold ≥2.3% (vs. < 2.3%), plaque burden was significantly higher (p = 0.02). CONCLUSION: These findings suggest that individuals with higher coronary plaque burden are more likely to get greater benefit from statin therapy even among asymptomatic individuals with low cardiovascular risk.