George Keith, Shave Rob, Oxborough David, Cable Tim, Dawson Ellen, Artis Nigel, Gaze David, Hew-Butler Tamara, Sharwood Karen, Noakes Tim
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, 15-21 Webster Street, Liverpool L3 2ET, UK.
Eur J Echocardiogr. 2009 Mar;10(2):238-43. doi: 10.1093/ejechocard/jen207. Epub 2008 Jul 29.
Assessment of the left ventricular responses to prolonged exercise has been limited by technology available to assess cardiac tissue movement. Recently developed strain and strain rate imaging provide the unique opportunity to assess tissue deformation in all planes of motion.
Nineteen runners (mean+/-SD age; 41+/-9 years) were assessed prior to and within 60 min (34+/-10 min) of race finish (Comrades Marathon, 89 km). Standard echocardiography assessed ejection fraction and the ratio of early to atrial (E/A) peak transmitral blood flow velocities. Myocardial speckle tracking determined segmental strain as well as systolic and diastolic strain rates in radial, circumferential, and longitudinal planes. Cardiac troponin T (cTnT) assessed cardiomyocyte insult. Ejection fraction (71+/-5 to 64+/-6%) and E/A (1.47+/-0.35 to 1.25+/-0.30) were reduced (P<0.05). Peak strain and peak systolic and diastolic strain rates were altered post-race in circumferential (e.g. peak strain reduced from 21.3+/-2.4 to 17.3+/-3.2%, P<0.05) and radial planes. Some individual heterogeneity was observed between segments and planes of motion. A post-race elevation in cTnT (range 0.013-0.272 microg/L) in 5/12 runners did not differentiate changes in LV function.
Completion of the Comrades Marathon resulted in a depression in ejection fraction, E/A, as well as radial and circumferential strain and strain rates. Group data, however, masked some heterogeneity in cardiac function.
对长时间运动时左心室反应的评估一直受到评估心脏组织运动的现有技术的限制。最近开发的应变和应变率成像提供了在所有运动平面评估组织变形的独特机会。
19名跑步者（平均年龄±标准差；41±9岁）在比赛结束前（战友马拉松赛，89公里）以及比赛结束后60分钟内（34±10分钟）接受评估。标准超声心动图评估射血分数以及二尖瓣血流早期与心房（E/A）峰值流速比值。心肌斑点追踪确定径向、圆周和纵向平面的节段应变以及收缩期和舒张期应变率。心肌肌钙蛋白T（cTnT）评估心肌细胞损伤情况。射血分数（71±5%降至64±6%）和E/A（1.47±0.35降至1.25±0.30）降低（P<0.05）。比赛后圆周平面（如峰值应变从21.3±2.4%降至17.3±3.2%，P<0.05）和径向平面的峰值应变以及峰值收缩期和舒张期应变率发生改变。在运动节段和平面之间观察到一些个体异质性。5/12名跑步者赛后cTnT升高（范围0.013 - 0.272微克/升）并未区分左心室功能的变化。
完成战友马拉松赛导致射血分数、E/A以及径向和圆周应变及应变率降低。然而，群体数据掩盖了心脏功能的一些异质性。
