Integrated backscatter for the in vivo quantification of supraphysiological vitamin D(3)-induced cardiovascular calcifications in rats.

in Cardiovascular Toxicology (2011), 11(3), 244-52

Cardiovascular calcifications are frequently found in the aging population and are independent predictors of future cardiovascular events. Integrated backscatter (IB) of ultrasound reflectivity can easily ... [more ▼]

Cardiovascular calcifications are frequently found in the aging population and are independent predictors of future cardiovascular events. Integrated backscatter (IB) of ultrasound reflectivity can easily quantify calcifications. For this purpose, 30 male Wistar rats received 25,000 IU/kg/day of vitamin D(3) (group 1, n = 8), 18,800 IU/kg/day (group 2, n = 8), or injections with the vehicle only (group 3, n = 14), for 10 weeks. Echocardiographic calibrated IB (cIB) was measured and calculated at baseline and after 10 weeks, followed by ex vivo micro-CT and histopathology of the aortic valve, ascending aorta, and myocardium. After 10 weeks, the mean cIB value of the aortic valve was significantly higher for vitamin D(3)-dosed animals compared to controls. The mean cIB value of the ascending aorta and the myocardium was also significantly higher in group 1 compared to group 3. In vivo IB results were confirmed by ex vivo micro-CT and histopathology. In conclusion, IB is a non-ionizing, feasible, and reproducible tool to quantify cardiovascular calcifications in an in vivo rat model. The integration of IB in the standard echocardiographic examination for the quantification of cardiovascular calcifications could be useful for serial evaluation of treatment efficacy and for prognosis assessment. [less ▲]

Analysis of regional wall motion during contrast-enhanced dobutamine stress echocardiography: effect of contrast imaging settings.

in European Journal of Echocardiography (2009), 10(8), 956-60

Aims: Myocardial contrast perfusion echocardiography (MCE) allows simultaneous assessment of perfusion and function. However, low frame rate during MCE may reduce the viewer's ability to discern ... [more ▼]

Aims: Myocardial contrast perfusion echocardiography (MCE) allows simultaneous assessment of perfusion and function. However, low frame rate during MCE may reduce the viewer's ability to discern contractile dysfunction. This study sought to compare MCE and left ventricular opacification (LVO) settings with regard to wall motion abnormalities (WMA) at rest and during dobutamine stress echocardiography (DSE). Methods and results: In 50 patients scheduled for coronary angiography and with poor baseline image quality, MCE and LVO were performed during DSE. Regional wall motion was assessed and inter-observer agreement was determined for each imaging modality. The endocardial border score index was similar for both modalities. The wall motion score index (WMSCI) at peak stress using MCE was well correlated with WMSCI obtained with LVO (r2 = 0.9, P < 0.001). However, WMSCI at peak stress was underestimated by MCE (1.66 ± 0.58 with DSE-LVO vs. 1.535 ± 0.50 with DSE-MCE; P < 0.001). Inter-observer agreement on the presence of WMA was 0.65 for MCE and 0.67 for LVO at peak stress. Conclusion: Myocardial contrast perfusion echocardiography provides equal endocardial border delineation compared with LVO modality. Although the inter-observer agreement is slightly higher with LVO compared with MCE, it is not significantly different with MCE at peak stress. Despite the similar improvement in endocardial border delineation, LVO settings allow the detection of more WMA than MCE at peak stress, leading to a significantly higher accuracy for the detection of ischaemia in patients suspected of coronary artery disease when only wall motion is taken into account. [less ▲]

Valorisation of Microsimulation Model for Social Security Mimosis

Report (2008)

This report is part of the output of the project AG/01/116. The main objectives of project AG/01/116 were to further refine and validate the microsimulation model for social security, MIMOSIS, both by ... [more ▼]

This report is part of the output of the project AG/01/116. The main objectives of project AG/01/116 were to further refine and validate the microsimulation model for social security, MIMOSIS, both by extending the data coverage and refining the modules as through a comparative study of how MIMOSIS is positioned in an international perspective and also by use of MIMOSIS for evaluation of (hypothetical) policy reforms. [less ▲]