Early detection of cardiac-function impairment by echo-Doppler indices can assist in preventing further cardiac damage by modifying disease progression and treatment. We analyzed our thalassemia major patients database with 10 years cardiac follow-up. Included patients were under constant therapy and should have an initial echo-Doppler study with normal Shortening Fraction (SF > 30%) and reexamination within the last year. We identified patients who developed impaired left ventricular (LV) function in the last Echo and we attempted to find which measured indices could predict LV function impairment. Three hundred fifteen of the 632 database patients were enrolled. Twelve of them developed LV systolic dysfunction. There were no statistically significant differences in mean age, ferritin, and pretransfusion hemoglobin levels of the two groups. LV-systolic-dysfunction group was presenting statistically significantly higher LF end-systolic diameter (LVESD) index, lower SF, higher early transmitral peak flow velocities/late transmitral peak flow velocities (A) ratios, lower A value. All other echocardiographic parameters did not differ significantly. By receiver-operating characteristic analysis, we determined systolic and diastolic indices specificity and sensitivity for LV impairment: LVESD 97% specificity, 11% sensitivity (cutoff value 2.44 cm/m(2) ), SF 92.1 and 33.3% (cutoff value 33%). Regarding diastolic indices, A index was the best criterion (97.7% specificity, 25% sensitivity, cutoff value <or=0.36). Low values of the diastolic index A wave and increased values of the LVESD index were the earliest pathological findings in patients that finally developed LV systolic dysfunction. These parameters could be used as heart-dysfunction predictors with relatively good sensitivity and specificity.