Praecordial mapping of Q waves and RS ratio changes in acute myocardial infarction.

The theory related to the loss of R waves and appearance of Q waves in acute myocardial infarction is discussed. A method of praecordial mapping of RS ratio changes and the appearance of Q waves that occur in acute myocardial infarction is described. The serial changes in these electrocardiographic signs in 17 patients during acute infarction are recorded. The potential value of these serial measurements in delineating the extent of myocardial injury in patients with acute infarction, and evaluating the effects of any treatment aimed at limiting infarct size is discussed.