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Introduction : An optimal fluoroscopic working view projection (OP) with all three aortic sinuses aligned is crucial during trans‐catheter aortic valve implantation (TAVI). The aim of this study was to identify simple reference projection angles, which would act as a starting point for the operator to help determine OP for patients undergoing TAVI. Methods : During the period under consideration, 50 patients underwent TAVI. Procedural data and outcomes were collected prospectively on a dedicated database. Optimal angiographic deployment angles were achieved for all patients by starting in an anteroposterior caudal 15 degrees projection and then adjusting according to the initial image, with multiple small volume contrast injections undertaken to determine when all three aortic cusps were aligned (OP). Results : OP angles for the 50 cases were plotted on a graph. After normality testing confirmed that all angles were normally distributed, regression analysis enabled a regression line to be calculated. The equation for the regression line was defined as cranial/caudal intercept ?16.4 ± 1.5 (SE of the coefficient), P < 0.0001, slope of regression line LAO/RAO + 0.53 ± 0.1 (SE of the coefficient SE), P < 0.0001). Conclusions : As the regression line and its equation represents an acceptable estimate of the true relationship between Cranial/Caudal and LAO/RAO, to determine OP while remaining close to the regression line we suggest starting in LAO = 8.9, Caudal = ?11.4 (which represent the mean values of these two variables), and then increasing the caudal angle by approximately 0.5 degrees for every increase of 1 degree of the LAO angle or decreasing the caudal angle by 0.53 degrees for every decrease of 1 degree in LAO until all three aortic sinuses are in line which represents OP. © 2012 Wiley Periodicals, Inc.  相似文献   
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Neurotransmitters other than dopamine are recognized as having modulatory roles within the basal ganglia and can influence the basal ganglia dopaminergic system to alter activity of the direct and indirect pathways. Many nondopaminergic neurotransmitter systems have been implicated in the mechanisms contributing to the motor features of Parkinson's disease (PD). Thus, it is now well established that neurotransmitter systems, including glutamatergic, GABAergic, cholinergic, noradrenergic, serotonergic, opioidergic, histaminergic, and adenosinergic systems, are affected in the pathogenesis of PD. Nondopaminergic neurotransmitter systems are thus targets for the development of novel therapies for motor symptoms and motor complications in PD. Over the last 5 years, more than 20 randomized, control trials (RCTs) in PD investigating drugs that target several of these nondopaminergic neurotransmitter systems for the treatment of motor features have been completed. There are at least 15 additional RCTs that are ongoing or planned. Here, we review these RCTs to highlight the potential nondopaminergic pharmacological therapies for treatment of motor features of PD. Nondopaminergic drugs are not expected to replace dopaminergic strategies, but further development of these drugs will likely yield novel approaches with positive clinical implications. © 2012 Movement Disorder Society  相似文献   
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