Donal Erwan, Thebault Christophe, O'Connor Kim, Veillard David, Rosca Monica, Pierard Luc, Lancellotti Patrizio
Service de Cardiologie et de Maladies Vasculaires et CIC-IT 804, LTSI INSERM U 642, Centre Cardio Pneumologique, CHU Pontchaillou 2 rue Henri Le Guilloux, 35033 Rennes Cedex 9, France.
Eur J Echocardiogr. 2011 Mar;12(3):235-41. doi: 10.1093/ejechocard/jeq187. Epub 2011 Jan 17.
In aortic stenosis (AS), left ventricular (LV) adaptation to exercise has poorly been examined. Changes in LV ejection fraction may lack accuracy in identifying the presence of intrinsic myocardial impairment.
We sought to determine the impact of aortic stenosis (AS) on left ventricular (LV) longitudinal function at exercise in a series of asymptomatic patients with AS and preserved LV ejection fraction.
Long-axis function was assessed at rest and at exercise by using 2D speckle tracking of myocardial deformation in 207 AS patients (aortic valve area 0.87 ± 0.19 cm²) and 43 aged-matched control subjects. When compared with control subjects, patients with AS have reduced longitudinal myocardial function at rest (-20.2 ± 2.7 vs. -15.4 ± 4.0%) and at peak exercise (-25.0 ± 3.7 vs. -16.5 ± 4.9%) (P < 0.0001 for both). Exercise changes in global longitudinal strain were correlated with changes in LV ejection in controls but not in patients with AS. Changes in LV global longitudinal strain during test were lower in AS patients with an abnormal response to exercise (-0.5 ± 2.7 vs. -1.5 ± 2.8%, P = 0.001). In multivariate analysis, a lower global longitudinal strain at rest (P = 0.04), a higher increase in mean trans-valvular pressure gradient (P < 0.001) at exercise, and smaller exercise-induced changes in global longitudinal strain (P < 0.001) were associated with an abnormal exercise test.
In AS, subnormal LV function can be reliably identified by 2D strain imaging at rest and during a sub-maximal exercise. That sensitive measure of LV systolic function is depressed in AS and even more in patients having the most severe AS.
在主动脉瓣狭窄（AS）中，左心室（LV）对运动的适应性研究较少。左心室射血分数的变化在识别内在心肌损伤方面可能缺乏准确性。
我们试图确定主动脉瓣狭窄（AS）对一系列无症状AS患者且左心室射血分数保留的运动时左心室（LV）纵向功能的影响。
通过二维斑点追踪心肌变形评估207例AS患者（主动脉瓣面积0.87±0.19cm²）和43例年龄匹配的对照者静息和运动时的长轴功能。与对照者相比，AS患者静息时（-20.2±2.7对-15.4±4.0%）和运动峰值时（-25.0±3.7对-16.5±4.9%）纵向心肌功能降低（两者P<0.0001）。对照者中整体纵向应变的运动变化与左心室射血变化相关，而AS患者中不相关。运动试验中左心室整体纵向应变变化在运动反应异常的AS患者中较低（-0.5±2.7对-1.5±2.8%，P=0.001）。多变量分析中，静息时较低的整体纵向应变（P=0.04）、运动时平均跨瓣膜压力梯度较高的增加（P<0.001）以及运动诱导的整体纵向应变较小的变化（P<0.001）与异常运动试验相关。
在AS中，静息和次最大运动期间二维应变成像可可靠识别左心室功能异常。左心室收缩功能的这种敏感测量在AS中降低，在最严重AS患者中更是如此。
