Primary T wave abnormalities may also be non-specific, occurring in the absence of underlying cardiac disease, electrolyte abnormality or the administration of cardioactive drugs. They may be isolated, occurring only in leads V3 and V4, they may occur with and following the termination of supraventricular tachycardias. and they may be associated with hyperventilation and abrupt changes in position. This ECG is from a 31 year old female without cardiac disease. It is an example of a non-specific T wave abnormality localized to leads V2-V4. Although the cause of these isolated T wave abnormalities is unclear, it is important to recognize that changes in the sequence of repolarization resulting in such T wave changes may occur in the absence of cardiac pathology. The inappropriate diagnosis of cardiac disease solely on the basis of isolated T wave abnormalities may lead to changes in employment status, insurability and/or self image and should be avoided.