Bjällmark Anna, Larsson Matilda, Shahgaldi Kambiz, Lind Britta, Winter Reidar, Brodin Lars-Ake
School of Technology and Health, Royal Institute of Technology (KTH) Huddinge, Stockholm, Sweden.
Clin Physiol Funct Imaging. 2009 May;29(3):216-23. doi: 10.1111/j.1475-097X.2009.00860.x. Epub 2009 Mar 2.
Tissue Velocity Imaging (TVI) is a method for quantitative analysis of longitudinal myocardial velocities, which can be used during exercise and pharmacological stress echocardiography. It is of interest to evaluate cardiac response to different types of stress tests and the differences between upright and supine bicycle exercise tests have not been fully investigated. Therefore, the aim of this study was to compare cardiac response during supine and upright exercise stress tests.
Twenty young healthy individuals underwent supine and upright stress test. The initial workload was set to 30 W and was increased every minute by a further 30 W until physical exhaustion. Tissue Doppler data from the left ventricle were acquired at the end of every workload level using a GE Vivid7 Dimension system (>200 frames s(-1)). In the off-line processing, isovolumic contraction velocity (IVCV), peak systolic velocity (PSV), isovolumic relaxation velocity (IVRV), peak early diastolic velocity (E') and peak late diastolic velocity (A') were identified at every workload level.
No significant difference between the tests was found in PSV. On the contrary, E' was shown to be significantly higher (P<0.001) during supine exercise than during upright exercise and IVRV was significantly lower (P<0.001) during supine exercise compared to upright exercise.
Upright and supine exercise stress echocardiography give a comparable increase in measured systolic velocities and significant differences in early diastolic velocities.
组织速度成像（TVI）是一种用于定量分析心肌纵向速度的方法，可用于运动和药物负荷超声心动图检查。评估心脏对不同类型负荷试验的反应很有意义，而直立位与仰卧位自行车运动试验之间的差异尚未得到充分研究。因此，本研究的目的是比较仰卧位和直立位运动负荷试验期间的心脏反应。
20名年轻健康个体接受了仰卧位和直立位负荷试验。初始工作量设定为30W，每分钟增加30W，直至体力耗尽。使用GE Vivid7 Dimension系统（>200帧/秒）在每个工作量水平结束时采集左心室的组织多普勒数据。在离线处理中，确定每个工作量水平下的等容收缩速度（IVCV）、峰值收缩速度（PSV）、等容舒张速度（IVRV）、舒张早期峰值速度（E'）和舒张晚期峰值速度（A'）。
PSV在两种试验之间未发现显著差异。相反，仰卧位运动时的E'显著高于直立位运动（P<0.001），仰卧位运动时的IVRV显著低于直立位运动（P<0.001）。
直立位和仰卧位运动负荷超声心动图检查测得的收缩期速度增加相当，舒张早期速度存在显著差异。
