Background: In patients with severe left ventricular (LV) dysfunction due to acute myocardial infarction (AMI), revascularization improves systolic function. Torsional dysfunction is also present in such patients; however, whether revascularization improves LV torsion also is largely unknown. Methods: Forty-one patients who survived >30 days after AMI [ejection fraction (EF) 31 짹 6%, wall motion score index (WMSI) 1.73 짹 0.21] were examined at baseline and 6 months after percutaneous coronary intervention. LV torsion was assessed by speckle tracking imaging. Diastolic function was also assessed by transmitral pulsed-wave Doppler and tissue Doppler imaging at the medial mitral annulus. Results: At baseline, 69% of patients showed non-restrictive filling pattern, and 31% restrictive filling pattern. After revascularization, along with improvement in systolic function (EF 47 짹 10%, WMSI 1.51 짹 0.47, p < 0.01 for both), diastolic filling improved in most patients, with six patients (16%) still exhibiting restrictive filling pattern (p<0.05); furthermore E/E��� decreased, from 21.2 짹 12.5 to 15.9 짹 6.8 (p<0.05). LV global longitudinal strain (from -11.2 짹 3.7 to -12.2 짹 5.7) and torsion (from 1.7 짹 0.5 degree/cm to 1.9 짹 0.7 degree/cm) also improved after revascularization. Conclusion: Impairment of LV function observed in patients with AMI is associated with a decrease of LV torsion. In patients with severe LV dysfunction due to AMI, LV torsion may largely improve after revascularization. LV torsion is strongly related to LV systolic and diastolic functions.