chocardiography is now recognized as an integral diagnostic tool that enables noninvasive quantification of cardiac chamber size, ventricular mass, and function in the clinical setting. Furthermore, technological advancement in Doppler echocardiography enables quantitative assessment of ventricular diastolic function as well as systolic function. Thus, echocardiography has become an important cardiac imaging technique in a number of clinical trials evaluating the efficacy of drug treatments or new therapeutic strategies.A guideline for quantifying cardiac chamber size and function using echocardiography, and references values for Circulation Journal Vol.72, November 2008 these echocardiographic measurements, were provided by the American Society of Echocardiography in conjunction with the European Association of Echocardiography. 1 Likewise, Doppler echocardiographic criteria for assessing left ventricular (LV) diastolic function were provided by the Canadian Consensus, 2 European 3 and American Medical Association guidelines, 4 and diastolic function parameters were reported to decline gradually with age. 5 However, most of these data are derived from American and European populations and because physical 6,7 and racial 8-10 differences can influence cardiac chamber size and function, it is important to evaluate the echocardiographic parameters in other populations. Reference values based on a large Asian population have not been previously reported, although some investigators have reported these values in a small population. 11 In addition, most studies that have investigated the relationship between age and cardiac chamber size and function have focused on a few parameters and have not assessed all of them in a large population.Accordingly, we designed and conducted a multicenter study, the Japanese Normal Values for Echocardiographic Measurements Project (JAMP) study, to determine the normal values for echocardiographic measurements and evaluate the relationship between these parameters and age in a large, healthy Japanese population. J 2008; 72: 1859 -1866 (Received February 27, 2008 revised manuscript received June 11, 2008; accepted June 26, 2008; released online September 29, 2008)
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Plasma etching technologies such as reactive ion etching (RIE), isotropic etching, and ashing/plasma cleaning are the currently used booster technologies for manufacturing all silicon devices based on the scaling law. The needs-driven conversion from the wet etching process to the plasma/dry etching process is reviewed. The progress made in plasma etching technologies is described from the viewpoint of requirements for the manufacturing of devices. The critical applications of RIE, isotropic etching, and plasma ashing/cleaning to form precisely controlled profiles of high-aspect-ratio contacts (HARC), gate stacks, and shallow trench isolation (STI) in the front end of line (FEOL), and also to form precise via holes and trenches used in reliable Cu/low-k (low-dielectric-constant material) interconnects in the back end of line (BEOL) are described in detail. Some critical issues inherent to RIE processing, such as the RIE-lag effect, the notch phenomenon, and plasma-induced damage including charge-up damage are described. The basic reaction mechanisms of RIE and isotropic etching are discussed. Also, a procedure for designing the etching process, which is strongly dependent on the plasma reactor configuration, is proposed. For the more precise critical dimension (CD) control of the gate pattern for leading-edge devices, the advanced process control (APC) system is shown to be effective.
Several investigators have shown that the incidence of venous obstruction after pacemaker implantation was observed in 31-50% of pacemaker patients. However, these previous reports did not investigate the venous system prior to implantation. The aim of this study was to determine the incidence and risk factors for venous obstruction in patients with transvenous pacing leads. The study included 131 consecutive patients (64 men, 67 women; mean age 71.3 +/- 9.8 years) who were investigated using intravenous digital subtraction angiography (DSA) before and after permanent pacemaker implantation. Follow-up DSA was performed for a mean interval of 44 +/- 6 months after pacemaker lead implantation in 79 of 131 patients. A diameter narrowing > 60% was defined as an obstruction. Prior to implantation of pacing leads, venous obstruction was present in 18 (13.7%) of 131 patients. In 15 of these 18 patients, the obstruction was present at the site of the left innominate vein. Follow-up DSA, after implantation of pacing leads, showed that venous obstruction was observed in 26 (32.9%) of 79 patients. There were no significant differences between obstruction and nonobstruction groups in terms of age, sex, cardiothoracic ratio, left atrial dimension, left ventricular ejection fraction, baseline heart diseases for indication of pacemaker implantation, or number and body size of pacing leads. Neither clinical symptoms nor abnormal physical findings were observed in any patients. In conclusion, the incidence of venous obstruction after pacing lead implantation is less than that of previous reports, which might be related to the incidence of venous obstruction before pacing leads implantation.
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