The purpose of this study was to compare indicators of oxidative capacity obtained from 31P-magnetic resonance spectroscopy (31P-MRS) and near-infrared spectroscopy (NIRS) following a 21-day upper-limb cast immobilization. Eight healthy men (19.5±0.9 years, mean±SD) participated in this study. For all subjects, the non-dominant arm was immobilized for 3 weeks with a cast (IMM) and the dominant arm was measured as control (CON). We measured the following parameters for participants pre- and post-immobilization: forearm cross-sectional area (CSA) and maximal voluntary contraction (MVC) of the grip. The oxidative capacity was evaluated by the time constant for the recovery of muscle oxygen consumption (TcVo2mus) determined by NIRS and the time constant of PCr (TcPCr) by 31P-MRS. There was no significant change in forearm CSA. MVC, TcVo2mus, and TcPCr were significantly decreased 26.5%, 25.9% and 32.2%, respectively, post-immobilization. A positive correlation was found between pre- and post-immobilization in TcVo2mus and TcPCr. The TcVo2mus and TcPCr were decreased during the 3-week immobilization, and there was a positive correlation between TcVo2mus and TcPCr both pre- and post-immobilization. The result of this study indicates that NIRS determined oxidative capacity is useful in a clinical setup where muscle and vascular functions are compromised.

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Surgical aortic valve replacement is a gold standard therapy for severe aortic stenosis (AS). However, in the clinical setting, at least 30% of symptomatic patients with severe AS do not undergo surgery for replacement of the aortic valve, due to advanced age, severe left ventricular dysfunction, or the presence of multiple comorbidities. Transcatheter aortic valve implantation (TAVI) is a new procedure, developed as an alternative less invasive therapy of severe AS in patients who are not considered to be suitable candidates for surgery. Currently 2 valve systems, the Edwards SAPIEN system and the CoreValve system, are clinically available. The operators have to be extremely cautious during positioning and implantation of the valve because of aortic stenting under heart beating for calcified aortic valve. Recent results of clinical trials are reported and this article reviews clinical outline of TAVI.

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Shaggy aorta is an aorta in which there are extensive atheromatous ulcerations. We herein report a case treated by a stent graft. A 62-year-old woman with left 5th toe dry necrosis was diagnosed with shaggy aorta with Arteriosclerosis obliterans. After medical therapy, we performed surgical therapy. Due to the presence of insufficiently managed diabetes and severe obesity, we performed a stent graft with distal bypass. She was discharged after walking without any new embolisms. Stent grafts are sometimes not adapted to the shaggy aorta due to the embolism; however, is the grafts are believed to have low invasiveness and thus considered to be effective if carried out.

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