Kinetics of Left Ventricular Strains and Torsion During Incremental Exercise in Healthy Subjects The Key Role of Torsional Mechanics for Systolic-Diastolic Coupling
Kinetics of Left Ventricular Strains and Torsion During Incremental Exercise in Healthy Subjects The Key Role of Torsional Mechanics for Systolic-Diastolic Coupling
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DOI：
10.1161/circimaging.110.943522
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发表时间：
2010-09-01
影响因子：
7.5
通讯作者：
Nottin, Stephane
中科院分区：
文献类型：
--
作者：
Doucende, Gregory;Schuster, Iris;Nottin, Stephane
背景动态的收缩和舒张期应变和扭转力学的左心室（LV）和他们的关系舒张期充盈从来没有被评估在各种exercise intensity.Methods和Results-Speckle跟踪超声心动图进行了20名健康的久坐不动的受试者在休息和在一个渐进的次最大运动试验在20%，30%和40%的最大有氧功率。左室扭转随运动强度的增加而逐渐增加（10.5 ± 3.2至15.8 ± 4.5度; P < 0.001），而纵向应变在第一次负荷后保持不变，强调了扭转储备在运动期间收缩-舒张耦联中的关键作用。舒张期解旋增加（-88.7 +/- 34.2至-182.9 +/- 53.5度）。sort（1）; P < 0.01）与收缩期扭转增强相关（R = 0.61; P < 0.001），其增加幅度明显高于舒张期纵向和周向应变率（分别为119 +/- 64%对65 +/- 44%和57 +/-24%），强调了其对舒张期充盈的贡献。在努力过程中，峰值解旋的时间和舒张期机械事件的时间顺序没有变化。解旋主要由心尖旋转驱动，并确定二尖瓣开放和等容舒张时间（R分别为0.47和0.61; P < 0.001），而基底旋转、纵向和周向舒张期应变率是舒张早期充盈增加的主要决定因素（R = 0.64，0.79和0.81，分别; P < 0.001）.结论-斑点追踪超声心动图的使用为健康受试者在递增运动过程中的生理适应性LV力学提供了新的见解，强调了扭转力学的关键作用。这可能有助于更好地了解各种病理条件下舒张功能障碍和运动不耐受的机制。(Circ血管造影。2010;3：586-594.）
Background-The dynamics of systolic and diastolic strains and torsional mechanics of the left ventricle (LV) and their relation to diastolic filling never have been evaluated at various exercise intensities.Methods and Results-Speckle tracking echocardiography was performed in 20 healthy sedentary subjects at rest and during a progressive submaximal exercise test at 20%, 30%, and 40% of maximal aerobic power. LV twist increased progressively with exercise intensity (10.5 +/- 3.2 to 15.8 +/- 4.5 degrees; P < 0.001), whereas longitudinal strain remained unchanged after the first workload, underlining the key role of torsional reserve in systolic-diastolic coupling during exercise. The increase in diastolic untwisting (-88.7 +/- 34.2 to -182.9 +/- 53.5 deg . s(-1); P < 0.01) was correlated to enhanced systolic twist (R = 0.61; P < 0.001), and its magnitude of increase was significantly higher compared to diastolic longitudinal and circumferential strain rates (119 +/- 64% versus 65 +/- 44% and 57 +/- 24%, respectively), emphasizing its contribution to diastolic filling. The timing of peak untwisting and the chronology of diastolic mechanical events were unchanged during effort. Untwisting was driven mainly by apical rotation and determined mitral opening and isovolumic relaxation time (R = 0.47 and 0.61, respectively; P < 0.001), whereas basal rotation and longitudinal and circumferential diastolic strain rates were major determinants of increased early diastolic filling (R = 0.64, 0.79, and 0.81, respectively; P < 0.001).Conclusions-The use of speckle tracking echocardiography gives new insights into physiological adaptive LV mechanics during incremental exercise in healthy subjects, underlining the key role of torsional mechanics. It might be useful to better understand the mechanisms of diastolic dysfunction and exercise intolerance in various pathological conditions. (Circ Cardiovasc Imaging. 2010;3:586-594.)