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Purpose:To determine the relationship between coronary plaque detected with coronary computed tomographic (CT) angiography and clinical parameters and cardiovascular risk factors in asymptomatic patients with diabetes. Materials and Methods:All patients signed institutional review board-approved informed consent forms before enrollment. Two hundred twenty-four asymptomatic diabetic patients (121 men; mean patient age, 61.8 years; mean duration of diabetes, 10.4 years) underwent coronary CT angiography. Total coronary artery wall volume in all three vessels was measured by using semiautomated software. The coronary plaque volume index (PVI) was determined by dividing the wall volume by the coronary length. The relationship between the PVI and cardiovascular risk factors was determined with multivariable analysis. Results:The mean PVI (6standard deviation) was 11.2 mm 2 6 2.7. The mean coronary artery calcium (CAC) score (determined with the Agatston method) was 382; 67% of total plaque was noncalcified. The PVI was related to age (standardized b = 0.32, P , .001), male sex (standardized b = 0.36, P , .001), body mass index (BMI) (standardized b = 0.26, P , .001), and duration of diabetes (standardized b = 0.14, P = .03). A greater percentage of soft plaque was present in younger individuals with a shorter disease duration (P = .02). The soft plaque percentage was directly related to BMI (P = .002). Patients with discrepancies between CAC score and PVI rank quartiles had a higher percentage of soft and fibrous plaque (18.7% 6 3.3 vs 17.4% 6 3.5 [P = .008] and 52.2% 6 7.2 vs 47.2% 6 8.8 [P , .0001], respectively). Conclusion:In asymptomatic diabetic patients, BMI was the primary modifiable risk factor that was associated with total and soft coronary plaque as assessed with coronary CT angiography.q RSNA, 2014 Clinical trial registration no. NCT00488033

Coronary computed tomographic angiography (CCTA) is emerging as a key non-invasive method for assessing cardiovascular risk by measurement of coronary stenosis and coronary artery calcium (CAC). New advancements in CCTA technology have led to the ability to directly identify and quantify the so-called “vulnerable” plaques that have features of positive remodeling and low density components. In addition, CCTA presents a new opportunity for noninvasive measurement of total coronary plaque burden that has not previously been available. The use of CCTA needs also to be balanced by its risks and, in particular, the associated radiation exposure. We review current uses of CCTA, CCTA’s ability to measure plaque quantity and characteristics, and new developments in risk stratification and CCTA technology. CCTA represents a quickly developing field that will play a growing role in the non-invasive management of cardiovascular disease.

Objective Gadolinium enhanced coronary magnetic resonance angiography (MRA) at 3 Tesla appears to be superior to non-contrast methods. Gadofosveset is an intravascular contrast agent that may be well suited to this application. The purpose of this study was to perform an intra-individual comparison of gadofosveset and gadobenate for coronary MRA at 3 Tesla. Materials and Methods In this prospective randomized study, 22 study subjects [8 (36%) male; 27.9 ± 6 years; BMI = 22.8 ± 2 Kg/m2] underwent two studies using a contrast-enhanced inversion recovery three-dimensional fast low angle shot MRA at 3 Tesla. The order of contrast agent administration was varied randomly, separated by an average of 30 ± 5 days, using either gadobenate dimeglumine (Gd-BOPTA; Bracco, 0.1 mmol/Kg) or gadofosveset trisodium (MS-325; Lantheus Med, 0.03 mmol/Kg). Acquisition time, signal-to-noise ratio (SNR) of coronary vessels and contrast-to-noise ratio (CNR) were evaluated. Results Of 308 coronary arteries and veins segment analyzed, overall SNR of coronary arteries and veins segments were not different for the two contrast agents (132 ± 79 for gadofosveset vs 135 ± 78 for gadobenate, p=0.69). Coronary artery CNR was greater for gadofosveset in comparison to gadobenate (73.5 ± 46.9vs. 59.3 ± 75.7 respectively, p=0.03). Gadofosveset-enhanced MRA images displayed better image quality than gadobenate-enhanced MRA images (2.77 ± 0.61 for gadofosveset vs. 2.11 ± 0.51, P<.001). Inter- and intra-reader variability was excellent (ICC > 0.90) for both contrast agents. Conclusion Gadofosveset trisodium appears to show slightly better performance for coronary MRA at 3T compared to gadobenate.

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Background: Traditional preclinical echocardiography (ECHO) modalities, including 1-dimensional motion-mode (M-Mode) and 2-dimensional long axis (2D-US), rely on geometric and temporal assumptions about the heart for volumetric measurements. Surgical animal models, such as the mouse coronary artery ligation (CAL) model of myocardial infarction, result in morphologic changes that do not fit these geometric assumptions. New ECHO technology, including 4-dimensional ultrasound (4D-US), improves on these traditional models. This paper aims to compare commercially available 4D-US to M-mode and 2D-US in a mouse model of CAL.Methods: 37 mice underwent CAL surgery, of which 32 survived to a 4 week post-operative time point. ECHO was completed at baseline, 1 week, and 4 weeks after CAL. M-mode, 2D-US, and 4D-US were taken at each time point and evaluated by two separate echocardiographers. At 4 weeks a subset of mice underwent cardiac magnetic resonance (CMR) imaging to serve as a reference standard. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were compared between imaging modalities. Hearts were also collected for histologic evaluation of scar size and compared to wall motion severity index (WMSI).Results: 4D-US provides closer agreement of ESV (Bias: -2.55%) and EF (US Bias: 11.23%) 4 weeks after CAL when compared to CMR, outperforming 2D-US and M-mode estimations. 4D-US is also more reliable than other modalities when estimating EDV (r=0.88), ESV (r=0.86) and EF (r=0.74) at 1 week when compared to 4 week imaging. 4D-US also allows for rapid assessment of WMSI, which correlates strongly with infarct size by histology (r=0.77).Conclusion: 4D-US outperforms M-Mode and 2D-US for volumetric analysis 4 weeks after CAL. 4D-US also provides more reliable measurements at 1 week after CAL and has less inter-user variability that other modalities. 4D-US allows for rapid calculation of WMSI, which correlates well with histologic scar size.

Background: Traditional preclinical echocardiography (ECHO) modalities, including 1-dimensional motion-mode (M-Mode) and 2-dimensional long axis (2D-US), rely on geometric and temporal assumptions about the heart for volumetric measurements. Surgical animal models, such as the mouse coronary artery ligation (CAL) model of myocardial infarction, result in morphologic changes that do not fit these geometric assumptions. New ECHO technology, including 4-dimensional ultrasound (4D-US), improves on these traditional models. This paper aims to compare commercially available 4D-US to M-mode and 2D-US in a mouse model of CAL. Methods: 37 mice underwent CAL surgery, of which 32 survived to a 4 week post-operative time point. ECHO was completed at baseline, 1 week, and 4 weeks after CAL. M-mode, 2D-US, and 4D-US were taken at each time point and evaluated by two separate echocardiographers. At 4 weeks, a subset (n = 12) of mice underwent cardiac magnetic resonance (CMR) imaging to serve as a reference standard. End systolic volume (ESV), end diastolic volume (EDV), and ejection fraction (EF) were compared among imaging modalities. Hearts were also collected for histologic evaluation of scar size (n = 16) and compared to ECHO-derived wall motion severity index (WMSI) and global longitudinal strain as well as gadolinium-enhanced CMR to compare scar assessment modalities. Results: 4D-US provides close agreement of ESV (Bias:-2.55%, LOA: − 61.55 to 66.66) and EF (US Bias: 11.23%, LOA − 43.10 to 102.8) 4 weeks after CAL when compared to CMR, outperforming 2D-US and M-mode estimations. 4D-US has lower inter-user variability as measured by intraclass correlation (ICC) in the evaluation of EDV (0.91) and ESV (0.93) when compared to other modalities. 4D-US also allows for rapid assessment of WMSI, which correlates strongly with infarct size by histology (r = 0.77). Conclusion: 4D-US outperforms M-Mode and 2D-US for volumetric analysis 4 weeks after CAL and has higher interuser reliability. 4D-US allows for rapid calculation of WMSI, which correlates well with histologic scar size.

Abstract:Introduction: Metabolic syndrome is a powerful predictor of cardiovascular events independent of overt diabetes. Dietary restriction and weight loss modify metabolic syndrome components. This study addresses whether combination pharmacologic therapy focused on dyslipidemia provides additional benefit. Methods: This study examines the effect of 1 year of gemfibrozil, niacin and cholestyramine therapy on a baseline of aggressive dietary and lifestyle intervention in 143 clinically stable, nondiabetic patients with coronary disease, randomized into a double-blind, placebo-controlled trial. Results: Cohort characteristics included age 63 Ϯ 7 years, 92% men, 43% with previous myocardial infarction, systolic blood pressure 139 Ϯ 17 mm Hg, triglycerides 168 Ϯ 81 mg/dL and high-density lipoprotein cholesterol 34 Ϯ 6 mg/dL. The mean number of metabolic syndrome components decreased from 2.2 Ϯ 0.9 to 1.5 Ϯ 1.1, P Ͻ 0.001, and metabolic syndrome prevalence decreased from 38% to 18% (P Ͻ 0.001) for the entire cohort. In the lifestyle intervention and placebo group, the mean number of metabolic syndrome components decreased from 2.2 Ϯ 0.9 to 1.9 Ϯ 1.1 (P ϭ 0.01), and prevalence of metabolic syndrome decreased from 44% to 30% (P ϭ 0.15). A far more marked change was observed with lifestyle intervention and pharmacologic therapy: abnormal metabolic components decreased from 2.2 Ϯ 0.9 to 1.0 Ϯ 1.0 (P Ͻ 0.001), and prevalence of metabolic syndrome decreased from 32% to 6% (P Ͻ 0.001). Conclusions: The combination of gemfibrozil, niacin and cholestyramine has profound, beneficial effects on the components of metabolic syndrome. These benefits are additive to those seen with aggressive diet and lifestyle modification.