RESUMO
BACKGROUND AND OBJECTIVES: The speckle tracking method using 2-dimensional (2D) echocardiography is not affected by the tethering of neighboring segments and angulation. Global circumferential strain (GCS) of the left ventricle (LV) has been suggested as a systolic index and correlated with LV contractility. The purpose of this study was to investigate whether acute changes in preload affect global circumferential strain and to evaluate the usefulness of GCS by the speckle tracking method. SUBJECTS AND METHODS: 2D echocardiography was performed in 69 patients with end-stage renal disease before and after hemodialysis to measure the LV end-diastolic volume and LV ejection fraction. 2D images were acquired from the short-axis view of the mid-LV for the evaluation of GCS. RESULTS: Mean LV end-diastolic volume significantly decreased from 91.2+/-33.3 mL to 72.3+/-32.0 mL (p+/-0.05), and LV ejection fraction decreased from 63.6+/-13.1% to 60.0+/-11.2% (p=0.006) after hemodialysis. However, mean GCS showed no significant change after hemodialysis (17.2+/-5.3% vs. 16.6+/-4.7%, p=0.13). GCS was found to be well correlated with LV ejection fraction (r=0.54, p<0.05) and peak systolic mitral annular velocity (r=0.46, p=0.000), but not with LV preload (r=0.06, p=0.622). CONCLUSION: GCS using the speckle tracking method is a useful index for the evaluation of LV systolic function because it is not affected by acute preload change and is correlated with LV ejection fraction and peak systolic mitral annular velocity.