OBJECTIVE To evaluate whether changes in myocardial performance index (MPI or Tei index) were related to changes in other Doppler echocardiographic parameters after acute myocardial infarction, or had any independent prognostic impact in a 2-year observational study. RESULTS Seventy-one patients with acute myocardial infarction without heart failure were examined at baseline, 3 months, and 2 years. MPI was significantly related to end-diastolic and end-systolic volume indexes, ejection fraction, maximal velocity, and time velocity integral of early mitral filling wave at 3 months and 2 years. MPI did not contribute significantly to the prediction of any changes in the measures of diastolic or systolic function at 3 months or 2 years. Baseline MPI was significantly higher in patients who later developed heart failure(0.55 +/- 0.16)than in other patients(0.43 +/- 0.13, P = 0.006), but had no independent predictive power for the development of heart failure or death relative to end-systolic volume index and deceleration time of early mitral filling wave. CONCLUSIONS MPI did not accurately reflect changes in Doppler and two-dimensional echocardiographic measures of diastolic or systolic function during a 2-year follow-up after acute myocardial infarction, and did not have any independent prognostic impact.