Pieles Guido E, Gowing Lucy, Forsey Jonathan, Ramanujam Paramanantham, Miller Felicity, Stuart A Graham, Williams Craig A
Bristol Congenital Heart Centre, The Bristol Heart Institute, University Hospitals, Bristol NHS Foundation Trust, and National Institute for Health Research Cardiovascular Biomedical, Research Unit, Bristol Heart Institute, Bristol, United Kingdom
Children's Health and Exercise Research Centre, University of Exeter, Exeter, United Kingdom;
Am J Physiol Heart Circ Physiol. 2015 Dec 15;309(12):H2067-76. doi: 10.1152/ajpheart.00627.2015. Epub 2015 Oct 16.
Background left ventricular (LV) and right ventricular (RV) myocardial reserve during exercise in adolescents has not been directly characterized. The aim of this study was to quantify myocardial performance response to exercise by using two-dimensional (2-D) speckle tracking echocardiography and describe the relationship between myocardial reserve, respiratory, and metabolic exercise parameters. A total of 23 healthy boys and girls (mean age 13.2 ± 2.7 yr; stature 159.1 ± 16.4 cm; body mass 49.5 ± 16.6 kg; BSA 1.47 ± 0.33 m(2)) completed an incremental cardiopulmonary exercise test (25 W · 3 min increments) with simultaneous acquisition of 2-D transthoracic echocardiography at rest, each exercise stage up to 100 W, and in recovery at 2 min and 10 min. Two-dimensional LV (LV Sl) and RV (RV Sl) longitudinal strain and LV circumferential strain (LV Sc) were analyzed to define the relationship between myocardial performance reserve and metabolic exercise parameters. Participants achieved a peak oxygen uptake (V̇o 2peak) of 40.6 ± 8.9 ml · kg(-1) · min(-1) and a work rate of 154 ± 42 W. LV Sl and LV Sc and RV Sl increased significantly across work rates (P < 0.05). LV Sl during exercise was significantly correlated to resting strain, V̇o 2peak, oxygen pulse, and work rate (0.530 ≤ r ≤ 0.784, P < 0.05). This study identifies a positive and moderate relationship between LV and RV myocardial performance and metabolic parameters during exercise by using a novel methodology. Relationships detected present novel data directly describing myocardial adaptation at different stages of exercise and recovery that in the future can help directly assess cardiac reserve in patients with cardiac pathology.
青少年运动期间左心室(LV)和右心室(RV)心肌储备尚未得到直接描述。本研究的目的是通过二维(2-D)斑点追踪超声心动图量化运动时心肌性能反应,并描述心肌储备、呼吸和代谢运动参数之间的关系。总共23名健康男孩和女孩(平均年龄13.2±2.7岁;身高159.1±16.4厘米;体重49.5±16.6千克;体表面积1.47±0.33平方米)完成了递增心肺运动试验(以25瓦·3分钟递增),同时在静息状态、每个运动阶段直至100瓦以及恢复2分钟和10分钟时采集二维经胸超声心动图。分析二维左心室(LV Sl)和右心室(RV Sl)纵向应变以及左心室圆周应变(LV Sc),以确定心肌性能储备与代谢运动参数之间的关系。参与者的峰值摄氧量(V̇o 2peak)为40.6±8.9毫升·千克⁻¹·分钟⁻¹,工作率为154±42瓦。LV Sl、LV Sc和RV Sl在不同工作率下显著增加(P<0.05)。运动期间的LV Sl与静息应变、V̇o 2peak、氧脉搏和工作率显著相关(0.530≤r≤0.784,P<0.05)。本研究通过一种新方法确定了运动期间左心室和右心室心肌性能与代谢参数之间存在正向且中等程度的关系。检测到的关系提供了直接描述运动和恢复不同阶段心肌适应性的新数据,未来有助于直接评估心脏病理患者的心脏储备。