PANCE Cardiology Practice Test

ECG changes map to the heart’s territory watched by specific leads. The anterior wall is viewed mainly by the anterior chest leads V1 through V4. In an anterior wall transmural infarct you commonly see both Q waves and ST elevations in those leads, reflecting necrosis (Q waves) and acute injury (ST elevations) of the anterior myocardium. The other territories show their changes in different leads: inferior in II, III, aVF; lateral in I, aVL, V5–V6; posterior changes are seen as ST depression in the anterior leads (or tall R waves) due to reciprocal effects. So the presence of Q waves and ST elevations in the anterior leads points to an anterior wall infarction.