Standardisierte Kontrastmittelsonographie (CEUS) in der klinischen Akut- und Notfallmedizin sowie Intensivmedizin (CEUS-Akut)

Die Anaesthesiologie -     

Positive inotropic effects of epigallocatechin-3-gallate (EGCG) involve activation of Na+/H+ and Na+/Ca2+ exchangers

BACKGROUND: There is evidence that the tea catechin epigallocatechin-3-gallate (EGCG) modulates myocardial contractility. However, the underlying mechanisms remain to be determined. AIMS: To study potential signalling pathways involved in EGCG-induced contractile parameters. METHODS AND RESULTS: EGCG increased fractional shortening in rat cardiac myocytes and enhanced intracellular systolic Ca2+ concentrations. In isolated rat hearts, perfusion with EGCG resulted in significant, dose-dependent increase in peak systolic left ventricular pressure, as well as in contraction and relaxation velocities. Heart rate did not change. Inhibition of the beta1-receptor with metoprolol had no influence on the contractile effects of EGCG. Furthermore, levels of cAMP and phosphorylation of phospholamban did not change with EGCG, indicating that the beta-receptor pathway is not involved. The L-type Ca2+ channel inhibitors, nifedipine and gallopamil, failed to modulate EGCG-induced increase in contractility. However, the myocardial effects and intracellular calcium transients stimulated by EGCG were significantly reduced by the antagonist of the Na+/H+ exchanger (NHE) methyl-N-isobutyl amiloride (MIA), and by blocking of the reverse mode of the Na+/Ca2+ exchanger (NCX) by KB-R7943. CONCLUSION: These results indicate that Ca2+-dependent positive inotropic and lusitropic effects of EGCG are mediated in part via activation of the Na+/H+ exchanger and the reverse mode of the Na+/Ca2+ exchanger in the rat myocardium.     

MR imaging of acute intermittent porphyria mimicking reversible posterior leukoencephalopathy syndrome

Reversible posterior leukoencephalopathy syndrome (PLS) is characterized by headache, altered mental function, visual disturbances and seizures. Neuroimaging studies suggest a white-matter oedema, predominantly in the posterior parietal-temporal-occipital regions of the brain. We present the case of a 30-year-old woman who had suffered her first attack of acute intermittent porphyria (AIP). Following 1 week of abdominal pain she developed several generalized seizures, and hallucinations, and exhibited a progressive deterioration of the consciousness. T2-weighted images, especially fluid-attenuated inversion recovery (FLAIR) sequences showed bilateral lesions in the posterior frontal, parietal and occipital cortex and subcortical white matter. Following treatment with haematin and a high carbohydrate diet the patient's condition improved. Follow-up magnetic resonance imaging (MRI) revealed complete resolution of the lesions. To our knowledge, this is the first report concerning a completely reversible PLS in AIP.     

Intra-individual randomised comparison of gadobutrol 1.0?M versus gadobenate dimeglumine 0.5?M in patients scheduled for preoperative breast MRI

Objective

To demonstrate non-inferiority of gadobutrol versus gadobenate dimeglumine by intra-individually comparing 0.1?mmol/kg body weight doses for contrast-enhanced breast magnetic resonance imaging (MRI) and prospectively evaluating lesion detection and characterisation in a multicentre trial.

Methods

Two identical breast MRI examinations were performed in 72 patients with biopsy-proven breast cancer, separated by 1?C7?days. Gadobutrol 1.0?M or gadobenate 0.5?M were administered in a randomised order. Lesion detection and characterisation were performed by two independent blinded readers. Lesion tracking, which compared on-site readings and histology from surgery or biopsy, was performed by a third reader. Differences in lesion detection and characterisation were compared between the two contrast agents.

Results

Among 103 lesions, 96 were malignant and 7 were benign. No difference in lesion detection was identified between the contrast agents (82.33?% for gadobutrol, 81.60?% for gadobenate). Assessment of sensitivity in lesion characterisation and Breast Imaging Reporting and Data Systems showed no difference between gadobutrol (92.63?%) and gadobenate (90.53?%). Regarding morphology, there was more non-focal enhancement for gadobutrol than for gadobenate (P?=?0.0057).

Conclusion

Non-inferiority of gadobutrol compared with gadobenate was demonstrated for breast lesion detection and sensitivity in lesion characterisation in breast MRI.

Key Points

? Contrast-enhanced magnetic resonance imaging is now widely used for breast problems. ? Lesion detection in breast MRI differs according to the contrast agent. ? Thus we compared gadobutrol 1?M with gadobenate dimeglumine 0.5?M. ? Gadobutrol was non-inferior to gadobenate dimeglumine for detecting and characterising malignant lesions.     

Patient Activity after Total Hip Arthroplasty Declines with Advancing Age

Evaluation of patient activity is essential for clinical decision making before THA. To correlate age progression to patient activity after THA, we determined the number of walking cycles of 105 patients in different age groups by decades. Patients on average performed 6144 walking cycles per day (2.24 million cycles per year). Men were more active than women. The highest activity occurred in patients between 50 and 59 years of age, with a constant decrease in activity with advancing age. However, within age groups, we observed up to sixfold differences in the number of walking cycles per day. In addition to declining activity with advancing age, higher body mass index correlated with lower step counts. The high mean measured number of walking cycles, which were even higher than those reported for subjects without an arthroplasty, suggests patients benefit from THA. Female gender, advanced age, and obesity correlated with lower activity. Owing to the high intragroup variability of our results, preoperative evaluation of patient activity levels, individual patient factors, and patient demands, should be considered in clinical practice. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research. This work was performed at University of Heidelberg.     

Silent brain lesions in patients with isolated idiopathic optic neuritis. A clinical and nuclear magnetic resonance imaging study

Eight of 16 patients with isolated idiopathic optic neuritis were found to have one to several brain lesions by nuclear magnetic resonance scanning. The brain lesions were predominantly located in the periventricular white matter; their appearances, locations, and extents were similar to those seen in recent nuclear magnetic resonance studies of patients with definite multiple sclerosis. All of these brain lesions were clinically silent and were missed by computerized tomography. Idiopathic optic neuritis may be the only manifestation of a multicentric disease process that is disseminated in the central nervous system in the majority of cases.