长期体育锻炼增加心肌葡萄糖代谢利用率

The ^18F-FDG myocardial metabolic imaging in twenty seven pilots with regular aerobic training

目的研究长期进行大运动量体育锻炼的飞行员^18F-脱氧葡萄糖（^18F-FDG）心肌灌注显像的特点。方法27例无心血管病、糖尿病病史的长期进行大运动量锻炼的男性飞行员作为受检者，分为受检当日早餐禁食（17例）和早矮予以谷物餐（10例）两组。每名受检者都在静息和蹬车运动达到次极量心率要求下进行2次^99Tc^m-甲氧基已乙腈（^99Tc^m-MIBI）和^18F-FDG双核素心肌显像（共54例次），2次检查分别安排在相邻的2d。然后对每名受检者进行运动与静息状态下心肌灌注显像进行视觉对比，判断是否存在心肌缺血。再采用17节段模型视觉半定量法对其心肌代谢显像结果进行分析。结果全部受检者蹬车运动都达到次极量心率（195-年龄），全部受检者的运动与静息^99Tc^m-MIBI心肌灌注显像对比后皆未发现心肌缺血。视觉定性分析，早餐禁食组共有4例次^18F-FDGPET显像失败，不禁食组有1例次^18F-FDGPET显像失败，差异无统计学意义。经17节段视觉半定量分析，在所有节段早餐禁食与否对运动和静息状态^18F-FDG心肌代谢显像评分的影响差异均无统计学意义；在早餐禁食组，运动与静态的^18F-FDG心肌代谢显像评分在6个节段差异有统计学意义；在不禁食组，3个节段的^18F-FDG心肌代谢显像运动高于静息状态，差异具有统计学意义，其他节段无统计学差异。结论长期大运动量锻炼的受检者即使不接受保证心肌代谢处于糖负荷的措施也能获得完整清晰的^18F-FDG心肌代谢显像。长期锻炼可能提高心肌对于葡萄糖代谢的利用率，并进而提高心肌代i射的氧利用率。长期锻炼可直接提高心肌对于缺血缺氧的耐受能力。

Objective To evaluate the characteristics of myocardial is F-FDG imaging in pilots with regular aerobic exercise training. Methods Twenty seven healthy male pilots with regular aerobic exercise training were included in this study. The subjects were divided into fasting （ n = 17 ） or non-fasting group （n = 10）. Fluorine-18-labeled deoxyglucose and Tc-99m-sestamibi dual-nuclide myocardial imaging were obtained at rest and at target heart rate during bicycle ergometer test. The exercise and rest myocardial perfusion imaging were analyzed for myocardial ischemia presence. The myocardial metabolism imaging was analyzed with the visual semi-quantitative analyses model of seventeen segments. Results The secondary- extreme heart rate （195-age） was achieved in all subjects. There was no myocardial ischemia in all perfusion imaging. In the visual qualitative analyses, four myocardial metabolism imaging failed in the fasting group while one failed in the non-fasting group （ P 〉 0. 05 ）. In the visual semi-quantitative analyses, myocardial metabolism imaging scores at rest or exercise in all segments were similar between two groups （P〉0.05）. In the fasting group, the myocardial metabolism imaging scores during exercise were significantly higher than those at rest in 6 segments （ P 〈 0.05）. In the non-fasting group, the scores of 3 exercise myocardial metabolism imaging were significantly higher than those at rest （ P 〈 0.05 ）. Conclusion Satisfactory high-quality myocardial metabolism imaging could be obtained at fasting and exercise situations in subjects with regular aerobic exercise.