Whether distal protection devices (DPDs) during percutaneous coronary intervention (PCI) can improve myocardial function in patients with acute myocardial infarction (AMI) is still under debate. Using tissue Doppler imaging (TDI), we evaluate the global and regional left ventricular systolic and diastolic functions in patients with anterior AMI using DPDs compared with conventional PCI. Ninety-six patients with anterior AMI were randomly assigned to either PCI with DPDs (DPD, n = 46) or traditional PCI (control, n = 50) groups. At the 3- and 6-month follow-ups, the DPD group had a higher left ventricular ejection fraction than the control group (51.6 +/- 3.6 vs. 49.3 +/- 5.3% and 53.0 +/- 3.7 vs. 50.8 +/- 5.2%, respectively; both P < 0.05). Moreover, peak systolic (S (a)) and early diastolic (E (a)) mitral annular velocities obtained by TDI were significantly higher in the DPD group than in the control group (S (a): 7.57 +/- 0.53 vs. 7.12 +/- 0.62 cm/s and 7.71 +/- 0.63 vs. 7.32 +/- 0.59 cm/s; E (a): 7.23 +/- 0.78 vs. 6.89 +/- 0.86 cm/s and 7.49 +/- 0.69 vs. 7.04 +/- 0.85 cm/s, respectively; all P < 0.05). However, systolic and diastolic regional myocardial velocities significantly improved in the DPD group from the 1-month follow-up compared with those in the control group (all P < 0.05). Patients who received treatment with DPDs experienced enhanced improvement of cardiac function. Thus, anterior AMI patients can benefit from DPDs during PCI.