What does Anteroseptal T Wave changes mean? I have a history of Atrial Septal Defect and Sinus Tachycardia.

ECG abnomality. There may be EKG changes in ASD depending on its type, severity, right ventricular size, pulmonary hypertension etc. T wave changes in leads V1-V3 are anteroseptal changes (meaning changes occurring in front part of the wall dividing right and left chambers of heart). I would discuss with congenital heart specialist, may be you need repeat echo to reassess RV size and estimated pulmonary pressure.