929-63 Dobutamine Stress Cine Magnetic Resonance Imaging versus PET for Detection of Myocardial Viability

To identify viable myocardium before coronary revascularization, we prospectively submitted eleven patients (60±7 yrs; 11 M) with previous Q-wave myocardial infarction to 18FDG-Positon Emission Tomography and low-dose (5 to 10 μg/kg/min) dobutamine cine-MRI. 18FDG uptake > 60% was considered indicative of viable tissue. Ouantitation of systolic wall thickening/thinning (SW) was performed by use of a computer software allowing automatic detection of epicardial and endocardial outlines, at rest and under 5, 7.5 and 10 μg/kg/min of dobutamine. Heart slices of both 18FDG-PET scans and dobutamine cine-MRI were divided in 8 segments, matched and analyzed byobservers blinded to clinical data. Sixty-five segments were considered viable by 18FDG-PET; in this subgroup, rest SW thickening averaged 47±5% and improved by 43±8% under low-dose dobutamine. In the remaining 23 segments considered non viable by PET. rest SW thickening averaged 14±7%*(*p<0.05 vs viable segment group) and further worsened by –13±8%*during low-dose dobutamine stress (*p<0.05 versus viable segment group). Positive predictive value of low-dose dobutamine stress cine-MRI for assessment of myocardial viability was 84%. These data suggest that quantitative assessment of regional wall motion by dobutamine cine-MRI may help discriminate viable from non viable myocardium as defined by 18FDG-Positon Emission Tomography

Effect of contrast material injection protocol on first-pass myocardial perfusion assessed by dual-energy dual-layer computed tomography

Background: Dual-energy dual-layer computed tomography (CT) scanners can provide useful tools, such as iodine maps and virtual monochromatic images (VMI), for the evaluation of myocardial perfusion defects. Data about the influence of acquisition protocols and normal values are still lacking. Methods: Clinically indicated coronary CT-angiographies performed between January-October 2018 in a single university hospital with dual-energy dual-layer CT (DE-DLCT) and different injection protocols were retrospectively evaluated. The two protocols were: 35 mL in patients <80 kg and 0.5 mL/kg in patients >80 kg at 2.5 mL/sec (group A) or double contrast dose at 5 mL/sec (group B). Patients with coronary stenosis >50% were excluded. Regions of interest were manually drawn on 16 myocardial segments and iodine concentration was measured in mg/mL. Signal-to-noise, contrast-to-noise ratios (CNR) and image noise were measured on conventional images and VMI. Results: A total of 30 patients were included for each protocol. With iodine concentrations of 1.38 +/- 0.41 mg/mL for protocol A and 2.07 +/- 0.73 mg/mL for protocol B, the two groups were significantly different (P<0.001). No significant iodine concentration differences were found between the 16 segments (P=0.47 and P=0.09 for group A and B respectively), between basal, mid and apical segments for group A and B (P=0.28 and P=0.12 for group A and B respectively) and between wall regions for group A (P=0.06 on normalised data). In group B, iodine concentration was significantly different between three wall regions [highest values for the lateral wall, median =2.03 (1.06) mg/mL]. Post-hoc analysis showed highest contrast-to-noise and signal-to-noise in VMI at 40 eV (P<0.05). Conclusions: Iodine concentration in left ventricular myocardium of patients without significant coronary artery stenosis varied depending on the injection protocol and appeared more heterogeneous in different wall regions at faster injection rate and greater iodine load. Signal-to-noise and contrast-to-noise gradually improved when decreasing VMI energy, although at the expenses of higher noise, demonstrating the potential of DE-DLCT to enhance objective image quality

Preventing acute decrease in renal function induced by coronary angiography (PRECORD): a prospective randomized trial

SummaryBackgroundInfusion of saline attenuates the decrease in renal function induced by radiographic contrast agents among patients with chronic renal insufficiency.AimThe Preventing Renal alteration in Coronary Disease (PRECORD) trial was a randomized trial to assess the effect on renal function of saline infusion during and after coronary angiography in 201 patients without severe chronic renal insufficiency (serum creatinine<140μmol/L).MethodsAll patients received standard oral hydration: 2000mL of tap water within the 24hours after coronary angiography. Patients were randomized before the procedure to intravenous hydration (1000mL of 0.9% saline infusion) or no additional hydration. The infusion was started in the catheterization laboratory and continued for 24hours. The primary endpoint was the change in calculated creatinine clearance between baseline and 24hours after coronary angiography. The same ionic low osmolar radiographic contrast agent (ioxaglate) was used in all patients.ResultsBoth groups had similar baseline characteristics, including age, serum creatinine, volume of contrast and proportion of patients undergoing ad hoc coronary angioplasty. The overall decrease in serum creatinine clearance 24hours after the procedure was –3.44 (0.68)mL/min. The change in serum creatinine clearance 24hours after the procedure was –2.81 (1.07)mL/min in the infusion group vs –4.09 (0.91)mL/min in the control group (p=0.38).ConclusionRenal function is altered only slightly 24hours after coronary angiography with standard oral hydration alone and is not affected by saline infusion started at the beginning of coronary angiography, even in patients with mild-to-moderate renal dysfunction

Determination of the myocardial area at risk after reperfused acute myocardial infarction with different imaging techniques: cardiac magnetic resonance imaging, multidetector computed tomography and histopathological validation

International audiencen.

En situation de catabolisme musculaire, les protéines de lactosérum permettent bien de restaurer un anabolisme musculaire post prandial mais d’une durée très transitoire probablement insuffisante pour limiter la fonte musculaire

En situation de catabolisme musculaire, les protéines de lactosérum permettent bien de restaurer un anabolisme musculaire post prandial mais d’une durée très transitoire probablement insuffisante pour limiter la fonte musculair

Whey proteins promote post prandial positive nitrogen balance in a muscle wasting situation but probably for a too short period of time to translate into muscle sparing

Background and aims: Muscle wasting occurred by an imbalance of muscle protein metabolism. Most of catabolic states are characterized by both an insulin and amino acid resistance which result into a food intake inefficiency to promote positive nitrogen balance during the post prandial period. So far, fast digested proteins (i.e whey) have been shown to be more efficient than casein to promote a stimulation of muscle protein synthesis (PS) in such situations; however, muscle mass is rarely improved. Our hypothesis is that this stimulation occurs only for a short period of time in the fed state, which remains insufficient to induce a significant increase in muscle mass. To address this point, a PS and proteolysis (PRO) kinetic study at the muscle level is required.Methods: Adult mini pigs were catheterized into both the femoral artery and vein and infused with 13C Phe to assess continuously) muscle PS and PRO in the hindlimb by the substrate and tracer arterio-venous difference method (every 30min before (PA) and after food intake). The catabolic state was induced by glucocorticoid treatment (8d); both casein and whey effects on PS and PRO were tested over time for 6.5 h.Results: After glucocorticoids, animals were in negative nitrogen balance at PA and casein intake had no effect on both PS and PRO and animals remained in negative nitrogen balance during the whole postprandial period. With whey, treated animals are able to generate a positive nitrogen balance for 120min after food intake (PS:+40% and PRO:-20%) which decreased thereafter along the postprandial period. Glucocorticoids were associated with insulin resistance (postprandial period: increased insulin/glycaemia). When fed whey, animals still presented hyperinsulinemia but normalized postprandial glycaemia.Conclusions. Whey are more efficient to generate positive muscle nitrogen balance in catabolic states but it remained only for a short period of time which may limit their efficiency on muscle wasting. Nutritional strategies have to be studied to optimize the duration of whey efficiency in the catabolic states. By contrast, whey are interesting to control post prandial hyperglycaemia in muscle protein wasting situations

Effect of Cyclosporine on Left Ventricular Remodeling After Reperfused Myocardial Infarction

ObjectivesThis study examined the effect of a single dose of cyclosporine administered at the time of reperfusion on left ventricular (LV) remodeling and function by cardiac magnetic resonance 5 days and 6 months after myocardial infarction.BackgroundIn a human study, administration of cyclosporine at the time of acute reperfusion was associated with a smaller infarct size.MethodsTwenty-eight patients of the original cyclosporine study had an acute (at 5 days) and a follow-up (at 6 months) cardiac magnetic resonance study to determine LV volumes, mass, ejection fraction, myocardial wall thickness in infarcted and remote noninfarcted myocardium, and infarct size.ResultsThere was a persistent reduction in infarct size at 6 months in the cyclosporine group compared with the control group of patients (29 ± 15 g vs. 38 ± 14 g; p = 0.04). There was a significant reduction of LV end-systolic volume (and a trend for LV end-diastolic volume; p = 0.07) in the cyclosporine group compared with the control group, both at 5 days and 6 months after infarction. There was no significant difference between the 2 groups in either global LV mass or regional wall thickness of the remote noninfarcted myocardium at 5 days or 6 months. Attenuation of LV dilation and improvement of LV ejection fraction by cyclosporine at 6 months were correlated with infarct size reduction.ConclusionsCyclosporine used at the moment of acute myocardial infarction reperfusion persistently reduces infarct size and does not have a detrimental effect on LV remodeling. These results are preliminary and must be supported by further studies. (Ciclosporin A and Acute Myocardial Infarction; NCT00403728

Comparative assessment of image quality for coronary CT angiography with iobitridol and two contrast agents with higher iodine concentrations: iopromide and iomeprol. A multicentre randomized double-blind trial.

To demonstrate non-inferiority of iobitridol 350 for coronary CT angiography (CTA) compared to higher iodine content contrast media regarding rate of patients evaluable for the presence of coronary artery stenoses. In this multicentre trial, 452 patients were randomized to receive iobitridol 350, iopromide 370 or iomeprol 400 and underwent coronary CTA using CT systems with 64-detector rows or more. Two core lab readers assessed 18 coronary segments per patient regarding image quality (score 0 = non diagnostic to 4 = excellent quality), vascular attenuation, signal and contrast to noise ratio (SNR, CNR). Patients were considered evaluable if no segment had a score of 0. Per-patient, the rate of fully evaluable CT scans was 92.1, 95.4 and 94.6 % for iobitridol, iopromide and iomeprol, respectively. Non-inferiority of iobitridol over the best comparator was demonstrated with a 95 % CI of the difference of [-8.8 to 2.1], with a pre-specified non-inferiority margin of -10 %. Although average attenuation increased with higher iodine concentrations, average SNR and CNR did not differ between groups. With current CT technology, iobitridol 350 mg iodine/ml is not inferior to contrast media with higher iodine concentrations in terms of image quality for coronary stenosis assessment. • Iodine concentration is an important parameter for image quality in coronary CTA. • Contrast enhancement must be balanced against the amount of iodine injected. • Iobitridol 350 is non-inferior compared to CM with higher iodine concentrations. • Higher attenuation with higher iodine concentrations, but no SNR or CNR differences

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema