[Electrocardiographic Q wave is of no significance after myocardial infarction]

A Q wave has high specificity in identifying acute myocardial infarction and is associated with infarcts of a larger size. A considerable number of studies have addressed the prognostic value of the presence of a Q wave in the electrocardiogram before and after the introduction of thrombolytic therapy. Overall, these studies have demonstrated that a Q wave has slight, or even no, prognostic impact, especially in studies performed since the introduction of thrombolytic therapy. Some therapeutic choices have been suggested according to the presence or absence of Q waves. These suggestions depend basically on subgroup analysis with different results and hence have not documented that a Q wave has any value in therapeutic choices. A pathological Q wave has no significant prognostic value after a myocardial infarction and there is very doubtful documentation that a Q wave has any value for therapeutic choice.