Uated in adjacent cross-sectional multi-planar reconstructed images of the coronaries. Care was taken to correctly discriminate between iodinated blood (300?00 HU) and calcified plaque, and Gaussian algorithms were used to distinguish between components of low to intermediate attenuation (0 to 150 HU) and calcified plaque components with higher attenuation values. By this model, components with different signal intensity within the plaque are separated, using a mixture Gaussian model, into a linear combination which includes 1? Gaussians curves. For each coronary lesion the following parameters were assessed: 1) Non-calcified plaque volume for each individual lesion and per patient, by summing up the individual volumes of lowattenuation or mixed plaques in all coronaries, Plaque composition by percentage of calcified content. According to the calcium content, plaques were classified into (i) low-attenuation (calcium content,20 ), (ii) mixed (calcium content between 20 ?0 ) and (iii) calcified (calcium content.80 ). Low-attenuation and mixed plaques (with non-calcified content 20 ) are expected to contain substantial amount of lipid cores or fibrotic tissues[7] apart from calcified tissue, and will be addressed to as `noncalcified’ plaques throughout our manuscript. Vascular remodeling, which was defined as a change in the vessel diameter at the plaque site in comparison to the reference segment proximal to the lesion (reference diameter). Quantification of the vessel diameters in longitudinal reconstructions, was used to assess the remodeling index (lesion diameter/reference diameter), which was considered positive when the diameter at the plaque site was 10 larger than that measured in the reference segment[7,11].2)256-slice CT BTZ-043 price Scanning TechniqueCT scans were performed using a 256-slice Brilliance iCT scanner (Philips Healthcare) that features a gantry rotation time of 270 ms, resulting in a temporal resolution of 36?35 ms, depending on the heart rate of the patient and the reconstruction mode, and an isotropic sub-millimeter spatial resolution. 3) (i) Coronary calcium scoring. For the assessment of coronary calcification prospective ECG-gated non-contrast scans were performed at 75 of the get Terlipressin cardiac cycle, and using 120 kV tube voltage and 364 mA tube current, and resultant images with a 3 mm slice thickness were used for the calculation of the Agatston score. CT Angiography (CTA) and estimation of the radiation dosage. For CTA a bolus of 80 ml of contrast agent (Ultravist 370, Bayer Healthcare) was injected intravenously (6 ml/s). As soon as the signal in the descending aorta reached a predefined threshold of 100 HU, the scan started automatically and the entire volume of the heart was acquired during one breath-hold in(ii)Measurement of High Sensitive Troponin T (hsTnT), High Sensitive CRP (hsCRP) and HMBGBlood samples were collected from all patients within 2 hours before the CTA scans, centrifuged and serum aliquots were storedHMGB1 and Atherosclerotic Plaque Compositionat 280uC until analysis. For hs-TnT quantification an ELECSYS 2010 automated analyzer was used (Roche Diagnostics, Mannheim, Germany). The diagnostic range of this assay is 3 to 10000 pg/ml with an inter-assay coefficient of variation of 8 at 10 pg/ ml, and 2.5 at 100 pg/ml. The intra-assay coefficient of variation is 5 at 10 pg/ml and 1 at 100 pg/ml. Hereby, based on a healthy reference population, an upper reference limit of 14 pg/ml (99th percentile for TnT).Uated in adjacent cross-sectional multi-planar reconstructed images of the coronaries. Care was taken to correctly discriminate between iodinated blood (300?00 HU) and calcified plaque, and Gaussian algorithms were used to distinguish between components of low to intermediate attenuation (0 to 150 HU) and calcified plaque components with higher attenuation values. By this model, components with different signal intensity within the plaque are separated, using a mixture Gaussian model, into a linear combination which includes 1? Gaussians curves. For each coronary lesion the following parameters were assessed: 1) Non-calcified plaque volume for each individual lesion and per patient, by summing up the individual volumes of lowattenuation or mixed plaques in all coronaries, Plaque composition by percentage of calcified content. According to the calcium content, plaques were classified into (i) low-attenuation (calcium content,20 ), (ii) mixed (calcium content between 20 ?0 ) and (iii) calcified (calcium content.80 ). Low-attenuation and mixed plaques (with non-calcified content 20 ) are expected to contain substantial amount of lipid cores or fibrotic tissues[7] apart from calcified tissue, and will be addressed to as `noncalcified’ plaques throughout our manuscript. Vascular remodeling, which was defined as a change in the vessel diameter at the plaque site in comparison to the reference segment proximal to the lesion (reference diameter). Quantification of the vessel diameters in longitudinal reconstructions, was used to assess the remodeling index (lesion diameter/reference diameter), which was considered positive when the diameter at the plaque site was 10 larger than that measured in the reference segment[7,11].2)256-slice CT Scanning TechniqueCT scans were performed using a 256-slice Brilliance iCT scanner (Philips Healthcare) that features a gantry rotation time of 270 ms, resulting in a temporal resolution of 36?35 ms, depending on the heart rate of the patient and the reconstruction mode, and an isotropic sub-millimeter spatial resolution. 3) (i) Coronary calcium scoring. For the assessment of coronary calcification prospective ECG-gated non-contrast scans were performed at 75 of the cardiac cycle, and using 120 kV tube voltage and 364 mA tube current, and resultant images with a 3 mm slice thickness were used for the calculation of the Agatston score. CT Angiography (CTA) and estimation of the radiation dosage. For CTA a bolus of 80 ml of contrast agent (Ultravist 370, Bayer Healthcare) was injected intravenously (6 ml/s). As soon as the signal in the descending aorta reached a predefined threshold of 100 HU, the scan started automatically and the entire volume of the heart was acquired during one breath-hold in(ii)Measurement of High Sensitive Troponin T (hsTnT), High Sensitive CRP (hsCRP) and HMBGBlood samples were collected from all patients within 2 hours before the CTA scans, centrifuged and serum aliquots were storedHMGB1 and Atherosclerotic Plaque Compositionat 280uC until analysis. For hs-TnT quantification an ELECSYS 2010 automated analyzer was used (Roche Diagnostics, Mannheim, Germany). The diagnostic range of this assay is 3 to 10000 pg/ml with an inter-assay coefficient of variation of 8 at 10 pg/ ml, and 2.5 at 100 pg/ml. The intra-assay coefficient of variation is 5 at 10 pg/ml and 1 at 100 pg/ml. Hereby, based on a healthy reference population, an upper reference limit of 14 pg/ml (99th percentile for TnT).
Posted inUncategorized