Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
Heart and Vascular Center, Semmelweis University, Budapest, Hungary.
Int J Cardiol. 2019 Feb 15;277:178-185. doi: 10.1016/j.ijcard.2018.10.092. Epub 2018 Nov 1.
Although exercise-induced cardiac hypertrophy has been intensively investigated, its development and regression dynamics have not been comprehensively described. In the current study, we aimed to characterize the effects of regular exercise training and detraining on left ventricular (LV) morphology and function.
Rats were divided into exercised (n = 12) and control (n = 12) groups. Exercised rats swam 200 min/day for 12 weeks. After completion of the training protocol, rats remained sedentary for 8 weeks (detraining period). Echocardiographic follow-up was performed regularly to obtain LV long- and short-axis recordings for speckle-tracking echocardiography analysis. Global longitudinal and circumferential strain and systolic strain rate were measured. LV pressure-volume analysis was performed using additional groups of rats to obtain haemodynamic data.
Echocardiographic examinations showed the development of LV hypertrophy in the exercised group. These differences disappeared during the detraining period. Strain and strain rate values were all increased after the training period, whereas supernormal values rapidly reversed to the control level after training cessation. Load-independent haemodynamic indices, e.g., preload recruitable stroke work, confirmed the exercise-induced systolic improvement and complete regression after detraining.
Our results provide the first comprehensive data to describe the development and regression dynamics of morphological and functional aspects of physiological hypertrophy in detail. Speckle-tracking echocardiography has been proven to be feasible to follow-up changes induced by exercise training and detraining and might provide an early possibility to differentiate between physiological and pathological conditions.
尽管运动引起的心脏肥大已经得到了深入研究，但它的发展和消退动态尚未得到全面描述。在本研究中，我们旨在描述规律运动训练和停训对左心室（LV）形态和功能的影响。
将大鼠分为运动组（n=12）和对照组（n=12）。运动组大鼠每天游泳 200 分钟，持续 12 周。完成训练方案后，大鼠保持安静 8 周（停训期）。定期进行超声心动图随访，获取左心室长轴和短轴记录，进行斑点追踪超声心动图分析。测量整体纵向和周向应变及收缩期应变率。使用额外的大鼠组进行左心室压力-容积分析，以获取血流动力学数据。
超声心动图检查显示运动组出现 LV 肥大。这些差异在停训期消失。应变和应变率值在训练后均增加，而超正常值在训练停止后迅速恢复到对照水平。负荷独立的血流动力学指标，如预负荷可诱发的搏功，证实了运动引起的收缩功能改善，并在停训后完全恢复。
我们的结果首次提供了详细描述生理肥大形态和功能方面发展和消退动态的全面数据。斑点追踪超声心动图已被证明可用于随访运动训练和停训引起的变化，并可能为区分生理和病理条件提供早期可能性。
