Extensive anterior wall myocardial infarction has a large infarct area, which refers to myocardial infarction from the septum to the anterior lateral wall. The electrocardiographic manifestations of extensive anterior wall myocardial infarction are as follows: i. Pathological Q waves can appear in the marker I, AVL, and V1-V6 leads with a depth of Q waves greater than 1/4R and a time frame greater than 0.04s, accompanied by an evolutionary process of ST segment and T waves. Second, ST-segment downshifts appear in the corresponding leads II, III, and AVF leads, which gradually return to the isochronous line with the duration of myocardial infarction. Third, some patients can have poor R-wave progression in chest leads V1-V6, which is shown as RV2>RV3>RV4>RV5>RV6. Fourth, individual patients have QS-type QRS wave groups in chest leads V1-V6.