Left ventricular (LV) torsional deformation plays an important role with respect to LV ejection and filling. However, no data are available on the impact of overload relief on LV torsional deformation after transcatheter ASD closure. This study sought to evaluate LV twist and untwisting before and early after device closure of ASD using the speckle tracking imaging (STI). We acquired basal and apical LV short-axis ultrasound images in 30 asymptomatic patients (29 +/- 9 years, 9 males) scheduled for percutaneous closure of an ASD before and 1-day after transcatheter ASD closure. All data were offline analyzed with Echopac 7.0 software. After transcatheter ASD closure, there was no significant difference in peak apical rotation and time to the peak (P > 0.05 for both). However, a significantly improved basal rotation was recorded, including significantly increased peak clockwise rotation (-7.1 +/- 3.2 degrees vs. -5.4 +/- 2.9 degrees , P = 0.014), decreased initial counterclockwise rotation (2.0 +/- 1.8 degrees vs. 5.1 +/- 3.2 degrees , P < 0.001) and shortened time to peak clockwise rotation (105.5 +/- 16.5% vs. 118.0 +/- 18.5% of systolic period, P = 0.001). LV twist was significantly improved in patients with ASD after the device closure (16.1 +/- 6.7 degrees vs. 12.2 +/- 6.3 degrees , P = 0.001), whereas there was no significant difference in peak untwisting rate, time to the peak and untwisting during IVRT (P > 0.05 for all). In conclusion, LV systolic twist could be significantly improved but diastolic untwisting remained unchanged after transcatheter ASD closure. This improvement was mainly attributed to the improved LV basal rotation rather than the unchanged apical rotation.