Early and late Q wave regression in the setting of acute myocardial infarction.

Abnormal Q waves after a myocardial infarction are not always an indicator of myocardial necrosis. In some cases these Q waves may disappear partially or completely in the evolution of the myocardial infarction. Five cases are described in whom complete Q wave regression and reappearance of R waves in the ECG leads corresponding to the affected area were observed. Q wave regression occurred early (hours) as well as late (months) after the myocardial infarction.